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DESIGN STANDARDS City of Auburn Engineering Division Public Works Department 25 West Main St. Auburn, WA 98001-4998 (253) 931-3010 FAX (253) 931-3053
DESIGN STANDARDS COMPRISED OF GENERAL REQUIREMENTS & DESIGN REQUIREMENTS AUGUST 2004 City of Auburn Engineering Division Public Works Department 25 West Main St. Auburn, WA 98001-4998
(253) 931-3010 FAX (253) 931-3053
City of Auburn Design Standards Table of Contents Chapter 1 – General Information Section: Page: 1.00 Preface 1-01 1.01 Contact Information 1-01 1.02 Reference Material 1-01 1.02.1 City
Reference Material 1-01 1.02.1.1 City of Auburn Construction Standards Manual 1-01 1.02.1.2 Engineering Handouts 1-02 1.02.1.2.1 Design Packets 1-02 1.02.1.2.2 General Handouts 1-02
1.02.1.2.3 Fee Related Handouts 1-02 1.02.1.2.4 Summaries 1-02 1.02.1.2.5 Technical Memos 1-02 1.02.2 Other Reference Material 1-03 1.03 Deviation from Standards 1-03 1.04 Contest of
City Engineer’s Decision 1-03 1.05 Changes to Standards 1-04 11/06/08 Design Standards Page i REF. H:\DEVELOPMENT\Manuals\Design Standards\TOC (11/08)
Chapter 2 – Plan Approval Process Section: Page: 2.00 Preface 2-01 2.01 Types of Plans 2-01 2.01.1 Grading Plans 2-01 2.01.2 Building Site Plans 2-01 2.01.3 Public Facility Extension
(FAC) Plans 2-02 2.01.4 Other Plans 2-02 2.02 Review and Approval Process 2-03 2.02.1 Submittals 2-03 2.02.2 City Review 2-04 2.02.3 Plan Approval 2-04 2.02.4 Project Close Out 2-05
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Chapter 3 – Plan Preparation Requirements Section: Page: 3.00 Preface 3-01 3.01 General Requirements 3-01 3.02 Plan Format 3-01 3.02.1 Grading Plans 3-01 3.02.2 Building Site Plans 3-02
3.02.3 Facility Extension (FAC) Plans 3-02 3.03 General Plan Requirements 3-02 3.03.1 Standard Plan Format 3-02 3.03.2 Drafting Standards 3-04 3.04 Plan Sheet Elements 3-04 3.04.1 Cover
Sheet 3-04 3.04.2 Temporary Erosion and Sediment Control (TESC) Plan Sheet 3-06 3.04.3 Grading Plan Sheet 3-07 3.04.4 Cross-Section Sheet 3-07 3.04.5 Detail Sheet 3-08 3.04.6 Grading
and Storm Drainage Plan Sheet 3-08 3.04.7 Utility Plan Sheet 3-09 3.04.7.1 Water 3-09 3.04.7.2 Sanitary Sewer 3-10 3.04.8 Utility Profile Sheet 3-10 3.04.8.1 Storm Drainage 3-10 3.04.8.2
Water 3-11 3.04.8.3 Sanitary Sewer 3-11 3.04.9 Public Street Plan and Profile Sheet 3-11 3.04.9.1 Plan View 3-11 3.04.9.2 Profile 3-12 3.04.9.3 Intersections 3-12 3.04.9.4 Typical Roadway
Sections 3-12 3.04.9.5 Striping and Signing 3-12 3.04.9.6 Signalization 3-12 3.04.9.7 Illumination 3-13 3.04.9.8 Streetscape 3-13 11/06/08 Design Standards Page iii REF. H:\DEVELOPMENT\Manuals\Design
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Chapter 3 – Plan Preparation Requirements (Cont.) Section: Page: 3.04.9.9 Other Features 3-13 3.04.10 Site Landscape Plan Sheet 3-13 3.04.11 Site Irrigation Plan Sheet 3-14 11/06/08
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Chapter 4 – Report Preparation Requirements Section: Page: 4.00 Preface 4-01 4.01 General Requirements 4-01 4.02 Report Types 4-01 4.02.1 Geo-Technical Reports 4-01 4.02.2 Storm Drainage
Reports 4-01 4.02.3 Other Reports. 4-02 4.03 Report Requirements 4-02 4.03.1 Geo-Technical Reports 4-02 4.03.2 Storm Drainage Reports 4-02 4.03.2.1 Background Computations for Sizing
Storm Drainage Facilities 4-04 4.03.2.2 Drainage Basin Report Summary 4-05 4.03.3 Other Reports 4-05 11/06/08 Design Standards Page v REF. H:\DEVELOPMENT\Manuals\Design Standards\TOC
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Chapter 5 – TESC, Clearing and Grading Section: Page: 5.00 Preface 5-01 5.01 TESC Design Criteria 5-01 5.01.1 Temporary Erosion and Sediment Control (TESC) 5-01 5.01.2 Temporary Detention
Systems 5-02 5.01.3 Temporary Retention Systems 5-02 5.01.4 Winterization Plan 5-03 5.02 Land Clearing 5-03 5.02.1 Purpose 5-03 5.02.2 Plan/Permit Requirements 5-04 5.02.3 General Requirements
5-04 5.03 Grading 5-04 5.03.1 Excavations 5-04 5.03.2 Fills 5-05 5.03.2.1 Preparation for Fill 5-05 5.03.2.2 Compaction 5-05 5.03.3 Slope Easement 5-05 5.04 Retaining Walls 5-06 5.04.1
Rockeries 5-06 5.04.1.1 Size 5-06 5.04.1.2 Material 5-06 5.04.1.3 Underdrains 5-06 5.04.2 Block Retaining Walls 5-06 5.04.2.1 Material 5-06 5.04.2.2 Underdrains 5-07 5.04.3 Reinforced
Concrete Walls 5-07 5.04.3.1 Material 5-07 5.04.3.2 Underdrains 5-07 5.04.4 Mechanically Stabilized Earth Walls (MSE Walls) 5-07 5.04.4.1 Material 5-07 5.04.4.2 Underdrains 5-07 5.05
Construction Sequence 5-07 5.05.1 Requirements 5-07 11/06/08 Design Standards Page vi REF. H:\DEVELOPMENT\Manuals\Design Standards\TOC (11/08)
Chapter 6 – Storm Drainage Section: Page: 6.00 Preface 6-01 6.01 General Requirements 6-01 6.02 Detention System Design Criteria 6-03 6.02.1 Detention Ponds 6-03 6.02.1.1 Purpose 6-03
6.02.1.2 Design 6-03 6.02.1.3 Dam Safety Requirements 6-04 6.02.2 Parking Lot Ponding 6-07 6.02.2.1 Purpose 6-07 6.02.2.2 Design 6-07 6.02.3 Detention Vaults 6-07 6.02.3.1 Purpose 6-07
6.02.3.2 Design 6-07 6.02.3.3 Detention Vault Inlet and Outlet Requirements 6-08 6.02.3.4 Detention Vault Access 6-08 6.03 Retention System Design Criteria 6-10 6.03.1 Purpose 6-10 6.03.2
Design 6-10 6.03.3 Retention System Infiltration Rate Requirements 6-10 6.03.4 Retention System Infiltration Rate Analysis 6-11 6.04 Discharge Control Requirements 6-11 6.04.1 Purpose
6-11 6.04.2 Design 6-11 6.04.3 Discharge Control Structures 6-12 6.05 Storm Drainage Quality Treatment 6-13 6.05.1 Purpose 6-13 6.05.2 General Requirements 6-13 6.05.3 Wetponds 6-13
6.05.3.1 Design Criteria 6-13 6.05.4 Wetvaults 6-17 6.05.4.1 Design Criteria 6-17 6.05.5 Bioswales 6-19 6.05.5.1 Design Criteria 6-19 11/06/08 Design Standards Page vii REF. H:\DEVELOPMENT\Manuals\De
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Chapter 6 – Storm Drainage (Cont.) Section: Page: 6.05.6 Oil/Water Separators 6-20 6.05.6.1 Design Criteria 6-20 6.05.7 Emerging Technologies 6-20 6.05.7.1 Design Criteria 6-20 6.06
Landscaping for Storm Drainage Facilities 6-21 6.06.1 Purpose 6-21 6.06.2 Design 6-21 6.06.3 Suggested Plants 6-22 6.06.3.1 Tree Selection Guide for Storm Drainage Detention/Retention
Facilities 6-22 6.06.3.2 Shrub Selection Guide for Storm Drainage Detention/Retention Facilities. 6-23 6.06.3.3 Perennial Groundcover Selection Guide for Storm Drainage Detention/Retention
Facilities 6-23 6.06.3.4 Shrub Selection Guide for Storm Drainage Detention/Retention Facilities 6-24 6.06.3.5 Grass Seed Mixes for Detention/Retention Facilities 6-24 6.06.3.6 Bioswale
Landscaping 6-25 6.06.3.6.1 Bioswale Grass Seed Mixes 6-25 6.06.3.6.2 Bioswale Suggested Plants 6-25 6.07 Storm Drainage Conveyance Systems 6-26 6.07.1 Purpose 6-26 6.07.2 Design 6-26
6.07.3 Public Street Drainage System Requirements 6-27 6.08 Stormwater Pollution Prevention Plan 6-27 6.08.1 Purpose 6-27 6.08.2 Stormwater Pollution Prevention Plan General Requirements
6-28 6.09 Public Storm Utility Easements 6-28 6.10 Material Requirements for Storm Drainage Systems 6-29 6.10.1 Storm Sewer Pipes 6-29 6.10.2 Storm Sewer Structures 6-29 11/06/08 Design
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Chapter 7 – Water Facilities Section: Page: 7.00 Preface 7-01 7.01 Design Criteria 7-01 7.01.1 Water Mains 7-01 7.01.1.1 Water Main Sizing 7-01 7.01.1.2 Water Main Location 7-02 7.01.1.3
Water Main Fittings 7-02 7.01.2 Water Services 7-03 7.01.2.1 Domestic Services 7-03 7.01.2.2 Other Services 7-04 7.01.3 Water Valves 7-04 7.01.3.1 Water Valve Sizing 7-04 7.01.3.2 Water
Valve Location 7-04 7.01.4 Pressure Reducing Stations 7-05 7.01.5 Fire Systems 7-05 7.01.5.1 Fire Hydrant Assemblies 7-05 7.01.5.2 Fire Sprinkler Systems 7-05 7.01.5.3 Fire Flows 7-06
7.01.5.4 Fire Department and Hydrant Access 7-07 7.02 Public Water Utility Easements 7-07 7.03 Material Requirements for Water Systems 7-07 11/06/08 Design Standards Page ix REF. H:\DEVELOPMENT\Manua
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Chapter 8 – Sanitary Sewer Facilities Section: Page: 8.00 Preface 8-01 8.01 Design Criteria 8-01 8.01.1 Sanitary Sewer Mains 8-01 8.01.1.1 Sanitary Sewer Main Sizing 8-01 8.01.1.2 Sanitary
Sewer Main Location 8-02 8.01.2 Sanitary Sewer Manholes 8-02 8.01.2.1 Sanitary Sewer Manhole Type and Size 8-02 8.01.2.2 Sanitary Sewer Manhole Locations 8-03 8.01.2.3 Sanitary Sewer
Manhole Parameters 8-03 8.01.3 Side Sewers 8-04 8.01.3.1 Side Sewer Parameters 8-04 8.01.4 Sanitary Sewer Cleanouts 8-04 8.01.5 Fats, Oils, and Grease, (FOG) and Sand/Grit Interceptors
8-05 8.01.6 Sanitary Sewer Pumps 8-06 8.02 Public Sanitary Sewer Utility Easements 8-06 8.03 Material Requirements for Sanitary Sewer Systems 8-06 8.03.1 Sanitary Sewer Pipes 8-06 8.03.2
Sanitary Sewer Structures 8-07 11/06/08 Design Standards Page x REF. H:\DEVELOPMENT\Manuals\Design Standards\TOC (11/08)
Chapter 9 – Utilities Section: Page: 9.00 Preface 9-01 9.01 Design Criteria 9-01 9.01.1 Private Utilities Located Within City Right-of-Way 9-01 9.01.1.1 Private Utilities Located Underground
9-01 9.01.1.2 Private Utilities Located Aboveground 9-01 9.01.2 Public and Private Utilities Located Underground Within City Right-of-Way 9-02 9.01.2.1 Perpendicular Trenching in Asphalt
Pavement 9-02 9.01.2.2 Longitudinal Trenching in Asphalt Pavement 9-03 9.01.2.3 Trenching in Concrete Pavement 9-03 9.01.2.4 Trenching in Other Right-of-Way Surfaces 9-03 11/06/08 Design
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Chapter 10 – Streets Section: Page: 10.00 Preface 10-01 10.01 Street Classifications 10-01 10.01.1 Arterials 10-01 10.01.1.1 Principal Arterial 10-02 10.01.1.2 Minor Arterial 10-02 10.01.2
Collectors 10-02 10.01.2.1 Residential Collector 10-02 10.01.2.2 Non-Residential Collector 10-02 10.01.2.3 Rural Collector 10-02 10.01.3 Local Streets 10-03 10.01.3.1 Local Residential
10-03 10.01.3.2 Local Non-Residential 10-03 10.01.3.3 Rural Residential 10-03 10.01.3.4 Private Street 10-03 10.01.4 Alleys 10-04 10.01.5 Private Access Roads (Shared Driveways) 10-04
10.01.6 Half-Streets 10-05 10.02 Street Design Requirements 10-07 10.02.1 Table 10-1 10-07 10.02.2 Street Geometry 10-08 10.02.2.1 Minimum Horizontal Curve Radius 10-08 10.02.2.2 Degree
of Horizontal Curvature 10-08 10.02.2.3 Tangents Between Reverse Curves 10-08 10.02.2.4 Superelevations 10-08 10.02.2.5 Vertical Grades 10-08 10.02.2.5.1 Vertical Curves 10-08 10.02.2.6
Cross Slopes 10-09 10.02.3 Right-of-Way 10-09 10.02.4 Roadway Width (Travel Way) 10-09 10.02.4.1 Inside Through Lanes and Curb Lanes 10-09 10.02.4.2 Center Turn Lanes 10-09 10.02.4.3
Other Lanes 10-09 11/06/08 Design Standards Page xii REF. H:\DEVELOPMENT\Manuals\Design Standards\TOC (11/08)
Chapter 10 – Streets (Cont.) Section: Page: 10.02.4.4 Road Edge 10-10 10.02.5 Street Layout 10-10 10.02.5.1 Residential Streets 10-10 10.02.5.2 Cul-de-sacs 10-10 10.02.5.2.1 Temporary
Cul-de-sacs 10-11 10.02.5.2.2 Permanent Cul-de-sacs 10-11 10.02.5.3 Traffic Volumes 10-11 10.03 Sight Distance 10-11 10.03.1 Sight Distance Categories 10-11 10.03.1.1 Stopping Sight
Distance 10-11 10.03.1.2 Decision Sight Distance 10-12 10.03.1.3 Passing Sight Distance 10-12 10.03.1.4 Intersection Sight Distance 10-12 10.03.2 Sight Distance Design 10-12 10.03.3
Table 10-2 10-13 10.03.4 Figure 10-1 10-14 10.03.5 Figure 10-2 10-15 10.04 Street Access Points 10-16 10.04.1 Public Street Intersections 10-16 10.04.1.1 Intersection Spacing 10-16 10.04.1.2
Horizontal Approach Angle 10-16 10.04.1.3 Curb and Right-of-Way Radius 10-16 10.04.1.4 Landing Approach 10-16 10.04.1.5 Street Crowns 10-16 10.04.2 Private Street Intersections 10-16
10.04.3 Table 10-3 10-17 10.04.4 Driveways 10-18 10.04.4.1 Driveway Locations 10-18 10.04.4.1.1 Functional Intersection Boundary 10-18 10.04.4.1.2 Table 10-4 10-19 10.04.4.1.3 Figure
10-3 10-19 10.04.4.1.4 Figure 10-4 10-20 11/06/08 Design Standards Page xiii REF. H:\DEVELOPMENT\Manuals\Design Standards\TOC (11/08)
Chapter 10 – Streets (Cont.) Section: Page: 10.04.4.2 Driveway Layout 10-21 10.04.4.3 Driveway Alignment (Horizontal & Vertical) 10-21 10.04.4.4 Driveway Widths 10-21 10.04.4.4.1 Residential
10-21 10.04.4.4.2 Commercial/Industrial 10-21 10.04.4.5 Restricted Access Driveways 10-22 10.05 Sidewalks 10-22 10.05.1 Width 10-22 10.05.2 Thickness 10-22 10.05.3 Meandering Sidewalks
10-23 10.05.4 ADA Access 10-23 10.06 Bikeways 10-23 10.07 Pavement Design 10-24 10.07.1 Design Requirements 10-24 10.07.1.1 Street Classification 10-24 10.07.1.2 Street Subgrade 10-24
10.07.1.3 Street Pavement Sections 10-25 10.07.2 Pavement Section Design Chart 10-26 10.07.3 Requirements for Engineered Pavement Sections 10-26 10.07.3.1 Traffic Requirements 10-26
10.07.3.2 Pavement Minimums 10-27 10.07.3.3 Soils Classifications 10-27 10.07.3.3.1 Poor Soils 10-27 10.07.3.3.2 Medium Soils 10-27 10.07.3.3.3 Good Soils 10-27 10.07.3.3.4 Excellent
Soils 10-27 10.07.3.3.5 Unified Soils Classification Symbols 10-28 10.07.3.4 Report Submittal 10-28 10.07.4 Materials Specifications 10-28 10.07.4.1 Gravel Base 10-28 10.07.4.2 Crushed
Rock 10-28 10.07.4.3 Asphalt Concrete Pavement 10-29 11/06/08 Design Standards Page xiv REF. H:\DEVELOPMENT\Manuals\Design Standards\TOC (11/08)
Chapter 10 – Streets (Cont.) Section: Page: 10.08 Landscaping 10-29 10.08.1 General Landscaping Requirements 10-29 10.08.2 Landscape Strip Components 10-29 10.08.3 Landscape Strip Dimensions
10-29 10.08.4 Plant Layers 10-29 10.08.5 Trees 10-30 10.08.5.1 Placement and Spacing 10-30 10.08.5.2 Tree Canopy Shape 10-31 10.08.5.2.1 V-Shaped Trees 10-31 10.08.5.2.2 Pyramidal Trees
10-31 10.08.5.2.3 Round Trees 10-31 10.08.5.2.4 Oval Trees 10-31 10.08.5.2.5 Columnar Trees 10-31 10.08.5.3 Root Direction Devices 10-31 10.08.5.4 Tree Planting Wells and Grates 10-31
10.08.6 Plant Selection 10-32 10.08.7 Plant Selection Table 10-33 10.08.8 Planting Methods and Maintenance 10-34 10.08.9 Establishment Period 10-34 10.08.10 Deviations from the Landscaping
Strip Standards 10-34 10.09 Mailboxes 10-35 10.09.1 Mailbox Locations 10-35 10.09.2 Mailbox Installation 10-35 10.10 Illumination 10-35 10.10.1 General 10-35 10.10.2 Design 10-35 10.10.3
Table 10-6 Lighting Schedule 10-36 10.10.4 Light Standard Foundations 10-36 10.10.5 Service Cabinet 10-36 10.10.6 Service Cabinet Foundations 10-36 10.10.7 Conduit 10-37 10.10.8 Junction
Boxes 10-37 10.10.9 Light Standards 10-37 10.10.10 Light Standard Handholes 10-36 11/06/08 Design Standards Page xv REF. H:\DEVELOPMENT\Manuals\Design Standards\TOC (11/08)
Chapter 10 – Streets (Cont.) Section: Page: 10.10.11 Photoelectric Controls 10-37 10.10.12 Luminaires 10-37 10.11 Survey Monuments 10-38 10.12 Guardrail 10-38 10.13 Bollards 10-39 10.14
Transit Stops 10-39 10.14.1 Bus Pullout Requirements 10-39 10.14.2 Locations for Bus Pullouts 10-39 10.14.3 Design of Bus Pullouts 10-38 10.15 Traffic Control Devices 10-40 10.15.1 Pavement
Markings 10-40 10.15.1.1 Crosswalks 10-40 10.15.1.2 Left-turn Channelization 10-40 10.15.1.3 Left-turn Lane at End of Two-way Left-turn Lane 10-40 10.15.1.4 Lane Division 10-40 10.15.1.5
Painted Islands 10-40 10.15.1.6 Two-way Left-turn Lanes 10-40 10.15.1.7 C-Curb 10-41 10.15.2 Signing 10-41 10.15.3 Construction Area Traffic Control 10-41 10.16 Roadway Barricades 10-41
10.17 Traffic Impact Analysis 10-42 11/06/08 Design Standards Page xvi REF. H:\DEVELOPMENT\Manuals\Design Standards\TOC (11/08)
11/06/08 Design Standards Page xvii REF. H:\DEVELOPMENT\Manuals\Design Standards\TOC (11/08) Chapter 11 – Site Design Section: Page: 11.00 Preface 11-01 11.01 Zoning Code Requirements
11-01 11.01.1 Building Setbacks and Lot Orientation Requirements 11-01 11.01.2 Landscaping 11-01 11.01.3 On-Site Parking Requirements 11-02 11.02 Land Use Approvals 11-02 11.02.1 Subdivisions
11-02 11.02.2 Planned Unit Developments 11-02 11.02.3 Gated Communities 11-02 Chapter 12 – City Telecommunication Utility Section: Page: 12.00 Preface 12-01 12.01 Design Criteria 12-01
12.01.1 Conduits 12-01 12.01.2 Splice Vaults and Pull Boxes 12-01
Chapter 1 -General Information 1.00 Preface The City of Auburn has adopted this Engineering Design Standards manual to encourage the standardization of design elements for consistency
and to assure that public safety needs are met. This manual contains engineering standards for use by professional civil engineers when designing facilities within the City of Auburn.
The information contained in this manual cannot provide for all situations and conditions that may be encountered. Specific provisions contained within this manual may not be appropriate
for all locations and existing conditions. These standards are intended to assist, but not substitute for, competent work by professional civil engineers. The design requirements contained
within this manual do not set legal standards of care, but provide guidance for possible engineering treatment under some circumstances. This chapter contains general information on
this manual and the City of Auburn. 1.01 Contact Information Permit Center Valley Regional Fire Authority Physical address: North Fire Station Auburn Professional Plaza (2nd Floor) 1101
"D" Street NE One East Main Street Auburn, Washington 98002-4016 Mailing Address: Phone: (253) 288-5800 25 West Main Street Fax: (253) 288-5900 Auburn, Washington 98001-4998 Public Works:
Phone: (253) 931-3010 Fax: (253) 931-3053 Planning & Development: Building Phone: (253) 931-3020 Planning Phone: (253) 931-3090 Fax: (253) 804-3114 1.02 Reference Material 1.02.1 City
Reference Material The reference material referred to herein may be obtained from the City of Auburn: 1.02.1.1 City of Auburn Engineering Construction Standards Manual The Engineering
Construction Standards manual sets forth the standards used during the construction of all civil projects within the City’s jurisdiction including the extension of public water, sanitary
sewer, storm drainage, and transportation facilities by private developments. The manual is comprised of two sections. Section I contains the City’s Standard Special Provisions and Section
II contains the City’s Standard Details. The Standard Special Provisions are a supplement to, and a modification of, the 02/16/2010 Design Standards Page 1-01 REF. H\DEVELOPMENT\Design
Standards\Chapter 1 (2-10)
“Washington State Department of Transportation (WSDOT/APWA) Standard Specifications for Road, Bridge and Municipal Construction,”. The Standard Details are comprised of the City’s construction
and design detail drawings for temporary erosion control, grading, water, sanitary sewer, storm drainage, and street work within the City that are supplemented by the “Washington State
Department of Transportation’s (WSDOT) Standard Plans.” 1.02.1.2 Engineering Handouts The following Handouts are currently available from the City to aid the public in planning and constructing
development projects within the City of Auburn. Contact the Permit Center for the most current list available. 1.02.1.2.1 Design Packets These handouts contain checklists for developing
a civil plan set for submittal, and updating approved civil plans after construction has been completed: A. Public Facility Extension (FAC) Submittal Packet B. Grading Permit (GRA) Submittal
Packet C. Record Construction Document Packet. 1.02.1.2.2 General Handouts These handouts contain information describing various City permit, plan or project requirements: A. Handout
of Minimum T.E.S.C. Requirements for Small Sites. B. Handout for Single Family Residential Roof Downspout and Footing Drain Construction. C. Handout on Accessing City Streets. 1.02.1.2.3
Fee Related Handouts These handouts contain information explaining some City development fees: A. Handout on Transportation Impact Fees. B. Handout on School Impact Fees. C. Handout
on Utility Connection Fees. 1.02.1.2.4 Summaries These handouts give a brief description of City policies and requirements: A. Developer Public Facility Extension Process Summary. B.
Summary of Half-Street Requirements. C. Summary of Guarantee/Bonding Requirements. 1.02.1.2.5 Technical Memos These handouts contain information that are subject to change or are too
specific to be included in this manual: A. Sanitary Sewer Pump Station Requirements and Standards. 02/16/2010 Design Standards Page 1-02 REF. H\DEVELOPMENT\Design Standards\Chapter 1
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1.02.2 Other Reference Material The following publications should be used as additional reference material for design applications not covered by the City’s publications: A. Washington
State Department of Transportation (WSDOT) “Standard Specifications for Street, Bridge and Municipal Construction” as amended by the City’s Construction Standards Section I. These will
be referred to in City publications as the "WSDOT Standard Specifications." B. Washington State Department of Transportation (WSDOT) “Design Manual” (latest edition). C. American Association
of State Highway and Transportation Officials’ (AASHTO) “A Policy on Geometric Design of Highways and Streets” (latest edition). D. State of Washington Department of Ecology’s “Criteria
for Sewage Works Design” (latest edition). E. State of Washington Department of Health (DOH) “Water Systems Design Manual” (latest edition). F. American Water Works Association (AWWA)
Standard Specifications (latest edition). G. “IES Lighting Handbook” (Illuminating Engineering Society of North America) (latest edition). H. American National Standard for Roadway Lighting
ANSI/IESNA RP-8-00 (latest edition). 1.03 Deviation from Standards The engineering design standards contained herein should be used when designing a development project within the City
of Auburn. In special cases, City standards may not best address a particular engineering application. In these instances, a design deviation from the City’s standards may be requested
from the City Engineer. All such requests shall include applicable engineering justification for the deviation. Deviation requests and supporting justification must be sealed by a licensed
professional civil engineer. The City Engineer will evaluate the request and notify the applicant of his/her decision within fifteen (15) working days of the receipt of a complete deviation
request. The following deviations may be obtained from the City of Auburn: 1.03.1 General Deviations General deviations apply to all engineering design standards except for the Surface
Water Management Manual’s Minimum Requirement deviations. The engineering design deviation when compelling supporting justification shall clearly demonstrate that the proposed deviation
will meet or exceed the corresponding City standard for the following applicable criteria: A. The functional intent of the design element. B. Safety factors associated with the design
element. C. Operational concerns associated with the design element. 02/16/2010 Design Standards Page 1-03 REF. H\DEVELOPMENT\Design Standards\Chapter 1 (2-10)
D. Maintenance concerns associated with the design element. E. Liability concerns associated with the design element. F. The capacity and/or efficiency of the design element. G. The
design life, historical performance, and durability of the design element. H. The aesthetic and visual impacts of the design element. I. The cost effectiveness and availability of any
replacement components or materials. J. Consistency with the spirit and purpose of the corresponding City design standard. K. Demonstration that the environment will not be adversely
affected. L. Supported by published industry standards. 1.03.2 Surface Water Management Manual Deviations 1.03.2.1 The Ten Minimum Requirements A deviation request from any of the ten
minimum requirements in the Surface Water Management Manual (SWMM) goes through a different process which includes a public notice requirement. This is to insure that the Department
of Ecology mandated surface water regulations are complied with. The ten Minimum Requirements of the City of Auburn Surface Water Management Manual are as follows: 1. Stormwater Site
Plan 2. Construction Stormwater Pollution Prevention Plan 3. Source Control of Pollution 4. Preservation of Natural Drainage Systems 5. On-site Stormwater Management 6. Runoff Treatment
7. Flow Control 8. Wetlands Protection 9. Operation and Maintenance 10. Off-site Analysis and Mitigation 1.03.2.2 Deviation Criteria Deviations from the ten Minimum Requirements of the
City of Auburn Surface Water Management Manual may be requested, in writing, in accordance with ACC 13.48.226 to allow a waiver of a requirement, a reduction or modification of a requirement,
or to permit an alternative requirement. Public notice of application for a deviation, decision, and written findings will be published in accordance with ACC 13.48.226. Deviations must
meet the following criteria: • The minimum requirements would impose a severe and unexpected economic hardship; and • The deviation will not increase risk to the public health and welfare,
nor injurious to other properties in the vicinity and/or downstream, and to the quality of waters of the state; and 02/16/2010 Design Standards Page 1-04 REF. H\DEVELOPMENT\Design Standards\Chapter
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• The deviation is the least possible exception that could be granted to comply with the intent of the Minimum Requirements. In accordance with ACC 13.48.226, the City Engineer may grant
a deviation following a documented finding that: A. The deviation is likely to be equally protective of public health, safety and welfare, the environment, and public and private property,
as the requirement from which an exception is sought; or B. Substantial reasons exist under ACC 13.48.226 C., for approving the requested deviation and the deviation will not cause significant
harm. The substantial reasons may include, but are not limited to: o The requirement to be imposed is not technically feasible; or o An emergency situation necessitates approval of the
deviation; or o No reasonable use of the property is possible unless the deviation is approved; or o The requirement would cause significant harm or a significant threat of harm to public
health, safety and welfare, the environment, or to public and private property, or would cause extreme financial hardship which substantially outweighs its benefits. The decision to
grant a deviation is within the sole discretion of the City, and the City Engineer shall only approve a deviation to the extent it is necessary. The City Engineer may impose new or additional
requirements to offset or mitigate harm that may be caused by approving the deviation. The City Engineer may require the applicant to submit a licensed engineer’s report or analysis
along with a request, in writing, for a deviation. Deviations are intended to maintain necessary flexible working relationship between the City and applicants. The approval of a deviation
shall not be construed to be an approval of any violation of any of the other provisions of the City’s Municipal Code, or of any other valid law of any governmental entity having jurisdiction.
Applications for a deviation from the Minimum Requirements of ACC13.48.225 must be in writing and include the following information: A. The current (pre-project) use of the site, and
B. How the application of the minimum requirement(s) restricts the proposed use of the site compared to the restrictions that existed prior to the adoption of the minimum requirements;
and C. The possible remaining uses of the site if the deviation were not granted; and D. The uses of the site that would have been allowed prior to the adoption of the minimum requirements;
and E. A comparison of the estimated amount and percentage of value loss as a result of the minimum requirements versus the estimated amount and percentage of value loss as a result
of requirements that existed prior to adoption of the minimum requirements; and F. The feasibility for the owner to alter the project to apply the minimum requirements. 02/16/2010 Design
Standards Page 1-05 REF. H\DEVELOPMENT\Design Standards\Chapter 1 (2-10)
02/16/2010 Design Standards Page 1-06 REF. H\DEVELOPMENT\Design Standards\Chapter 1 (2-10) 1.03.2.3 Public Notice Requirements The public notice will be issued after the decision and
any appeal of the decision per Section 1.04 has been completed. The following public notice requirements apply whenever a request for an exception to the Minimum Requirements contained
in ACC 13.48.225 is received by the City: A. Public notice (Notice) shall be made to inform the public about the contents of the Request and the City Engineer’s decision to grant or
deny it. Notice of the Request and the decision to grant or deny the Request may be combined. B. The Notice shall be published, at the requestor’s cost, in the City’s newspaper of record
and a local newspaper of general circulation
within Auburn. C. The Notice shall include: (i) a brief description of the Request; (ii) a brief description of the City Engineer’s decision to grant the Request and reasons supporting
the decision, or a statement that the request is denied; (iii) where the Request can be reviewed; and (iv) the name and contact information of a City employee who can answer questions
regarding the Request. D. The City shall provide a hardcopy of the City Engineer’s decision to grant or deny a Request to the requester. The City Engineer’s decision to approve or deny
a Request shall include a reference to the procedures in City of Auburn Engineering Design Standards for contesting such a decision. 1.04 Appeal of City Engineer’s Decision Appeal of
the City Engineer’s decision (Section 1.03) shall follow the following procedure: The applicant shall have fifteen (15) working days from the date of receipt of the City Engineer’s decision
in which to submit a written notice to the Public Works Director contesting the written decision of the City Engineer. The Public Works Director shall then have fifteen (15) working
days to notify the applicant of his/her decision to uphold or modify the City Engineer’s decision. For engineering deviations requests, the Director’s determination shall be final. If
the Public Works Director determines the nature of the deviation requires a nonengineering policy decision by the Public Works Committee of the Auburn City Council, the Public Works
Director shall seek such decision from the Committee at the next available Committee meeting. The Public Works Director shall notify the applicant within five (5) working days after
the Committee’s decision. 1.05 Changes to Standards The City of Auburn’s Public Works Committee is authorized to make any additions, deletions, or modifications stated in these Standards.
(ACC 12.04.010)
Chapter 2 – Plan Approval Process 2.00 Preface This chapter contains standards and procedures that apply to the review and approval process for civil engineering plans. Development or
redevelopment of property within the City of Auburn, and/or within the limits of Auburn’s Utility Service Area, that require civil engineered plans to support a development action must
follow the processes outlined below. 2.01 Types of Plans This section contains information regarding the types of civil engineering plans submitted to the City. Specific plan requirements
are described in detail in Chapter 3. Civil engineering plans submitted to the City for review fall within the following four categories. 2.01.1 Grading Plans Grading plans are required
prior to the issuance of a Grading Permit and before commencement of construction in the following situations: A. Any application made for a Grading Permit that includes excavations
and/or fills exceeding five hundred cubic yards (500 yd3) of material. B. An application made for for a Building Permit for all new non-residential developments and residential construction
of three units or more per lot. C. An application made for a Land Clearing Permit when the proposed work involves temporary roads and leveling of the site. D. An application made for
construction of a parking lot. E. An application made for a plat or a short plat that requires grading on the site resulting in the movement of over five hundred cubic yards (500 yd3)
of material. 2.01.2 Building Site Plans A Building Site Plan includes all civil site development requirements including site layout, site access, parking, utility service, and storm
drainage control. An approved Site Plan is required prior to the issuance of a Building Permit and before commencement of construction. Building Site Plans are required for the following
situations: A. A Building Site Plan along with a Grading Plan is required in association with a Building Permit application for all new non-residential developments and residential construction
of three (3) units or more per lot. B. Where an existing site is redeveloped such that new buildings and additions and/or alterations to existing buildings increase the assessed value
of the improvements on the property by greater than fifty percent (50%), and the new plus replaced impervious surface is five thousand square feet (5000 ft2) or more. C. Alteration of
site access requirements, and/or connect to and impact City streets and utilities. 2/16/2010 Design Standards Page 2-01 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 2 (2-10)
D. Convert ¾ acres or more of native vegetation to lawn/landscaped area or convert 2.5 acres or more of native vegetation to pasture.. E. The Change of Use of an existing site requires
one or more of the following. 1. The installation of onsite parking resulting in the addition of over five thousand square feet (5000 ft2) of impervious area. 2. The alteration of the
access to and from City streets including adding or removing driveways. 3. The installation of a new storm system to serve impervious area of over five thousand square feet (5000 ft2)
of impervious area. 4. The installation of code-required landscaping. (This will require the submittal of a landscape plan for review and approval by the City of Auburn Planning Department).
One example is the conversion of a residential property to a commercial use. The work covered by the Building Site Plan may include the building and grading work; however, the applicant
must make separate applications for a Building Permit and a Grading Permit. 2.01.3 Public Facility Extension (FAC) Plans An approved Public Facilities Extension Plan (FAC Plan) is required
prior to installing new or improving existing public sanitary sewer, water, storm drainage, and/or transportation facilities. FAC Plans are required in the following situations: A. With
a Building Site Plan when construction of the building requires the extension of a City water, sanitary sewer, or storm drainage facility. B. With a Building Site Plan when construction
of the building requires improvements to the City transportation facility. C. With a Grading Plan for public utility improvements within Plat and Short Plats. D. For county projects
where water and sanitary sewer mains within Auburn’s Utility Service Area are extended. Prior to preparing plans for submittal, the applicant should obtain a “Developer Public Facility
Extension Process Summary” from the City. This summary explains some of the basic requirements and steps of the FAC process. 2.01.4 Other Plans Some projects may also require other types
of plans. The requirements for these additional plans will usually be addressed early in the submittal process. These plans could include, but are not limited to, the following: A. Landscape
plans. B. Land clearing plans. C. Irrigation plans. D. Wetland plans. 2/16/2010 Design Standards Page 2-02 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 2 (2-10)
2.02 Review and Approval Process 2.02.1 Submittals When submitting civil engineering plans to the City for review, the following steps should be taken to insure a complete submittal
and timely approval of civil engineering plans: A. Applicants are encouraged to meet with City staff prior to plan submittal. (Pre-application information is available through the City
of Auburn) All plans and associated documents submitted to the City will be assigned a permit number and receive a preliminary review to make sure that they adequately address the minimum
requirements of a complete application. Any such plans and associated documents not meeting these requirements will be returned to the applicant or his designee as unacceptable for review,
with a written explanation of necessary corrections required prior to the subsequent resubmission. B. Prior to preparing civil engineering plans for submittal, the applicant should obtain
a Plan Submittal Packet from the City, for the appropriate type of plans. This packet contains information necessary to prepare plans in conformance with City guidelines. The checklists
within the Plan Submittal Packet shall be completed and submitted along with the civil engineering plans. C. Civil Engineering plans and associated documents are to be submitted to the
City for processing. D. After the receipt of a completed Facility Extension (FAC) Application and FAC application fees, the City will make a preliminary review of the plans and supporting
data to verify the scope of the proposed extension(s) and check for completeness of the application. Once the City is satisfied with the completeness of the application and has verified
the length of the extension(s), a letter will be sent requesting that the following be submitted before any detailed FAC Plan review work will be performed: 1. An executed Facility Extension
Agreement. 2. Forty percent (40%) of the total calculated Facility Extension fee. (The remaining sixty percent (60%) will be due prior to construction.) E. The following number of documents
and plans are required for a complete submittal: Plan sets Plan Submittal Packet Stormwater Site Plans Geotechnical Reports Grading Plans 5 1 2 1 Building Site Plans 10 1 2 1 FAC Plans
10 1 2 1 F. All Plans submitted to the City shall be non-ammonia based prints. G. All proposed public right-of-way dedications and easements not under the ownership of the applicant
shall be dedicated to the City prior to final plan approval. A title report will be required to confirm property ownership. 2/16/2010 Design Standards Page 2-03 REF. H:\DEVELOPMENT\Manuals\Design
Standards\Chapter 2 (2-10)
H. The following applicable information may be required along with the plan submittal: 1. Title report (required if right-of-way is being dedicated). 2. The final biologist report, including
the wetland mitigation plan when appropriate. 3. Traffic reports. 4. A copy of the final SEPA determination (for projects where the City isn’t the lead agency). 5. A copy of other applicable
applications (Short Subdivisions, Subdivisions, etc.). 6. Letter indicating how SEPA and/or other applicable application conditions have been accounted for in the development/plan process.
I. All plans, calculations, or reports submitted for review shall be stamped by a Washington State licensed professional civil engineer (PE). Mylar plans, calculations, and reports submitted
for final approval need to have the PE stamp wet signed and dated. J. Where the plan review process is running concurrent with other applications (SEPA, Subdivisions, etc.), the above-referenced
information may not be available at time of plan submittal. In such instances, other required applications shall be provided prior to final plan approval. 2.02.2 City Review The City
will review plans and associated calculations and reports for conformance with City development requirements, standards, and policies. Red-line construction drawings, calculations, reports,
and written plan review comments will be returned to the applicant’s designated contact person for revisions. The applicant’s engineer shall revise construction drawings, calculations,
or reports to address City plan review comments. The revised drawings (the required number will be determined by the City) and associated calculations and reports along with the redline
comments shall be resubmitted to the City for additional review. 2.02.3 Plan Approval Once the plan review process is completed and all City review comments have been addressed, the
City will request that one copy of sealed mylars be submitted for approval. A. Final reproducible plans shall be placed on a minimum 4-mil thick mylar and will be be signed by the City
Engineer or his designate and shall remain on file with the City. (Note: No sticky back transparencies, no sepia mylars, and no Xerox mylars are accepted by the City.) Upon approval,
the developer will be required to check out these mylars from the City and make the required number (6 to 18 sets) of prints for the City, plus any required for themselves or the contractors,
prior to issuance of any construction permits. B. All applicable AutoCAD files shall be submitted to the City on a compact or floppy disk along with the mylars for integration into the
City’s Geographic Information System (GIS). For more information on AutoCAD file submittal, please obtain a copy of the City’s “Record Construction Document Packet.” C. If after plan
approval but prior to construction the applicant chooses to make changes to the approved plans, a revised plan reflecting such changes may be required if the City determines the changes
will impact the City’s ability to insure construction is completed in conformance with City regulations. In such cases, 2/16/2010 Design Standards Page 2-04 REF. H:\DEVELOPMENT\Manuals\Design
Standards\Chapter 2 (2-10)
2/16/2010 Design Standards Page 2-05 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 2 (2-10) the revised plans shall be submitted to the City for review and a new revised Mylar
shall be provided for approval with the changes shown, sealed by the design engineer, and approved by the City. 2.02.4 Project Close Out The following is the basic process required for
accepting construction completion on a project: A. After completion of construction, a paper plan copy of the approved plan set shall be utilized for a dry run “as-built” set prior to
redlining the original Mylar set. A copy of the “Record Construction Document Packet” which outlines the complete record drawing process in detail can be obtained from the City. B. All
changes to the approved plan noted by the contractor and/or surveyor during the construction process shall be clearly indicated on the paper copy of the approved plan in red ink. C.
The “Record Drawing Certification” block on all sheets of the as-built paper set shall be signed and dated by the Engineer or Surveyor making the corrections and the plan set returned
to the City for verification by the City prior to these changes being made to the original Mylar set.. D. After approval of the redlined paper plan copy of the original approved plan
set, the approved original Mylars shall be checked out from the City, and the approved corrections shown on the approved “as-built” paper plan set shall be made on the original Mylars
in red ink. . These record drawings will become final once the City has verified the corrections are consistent with the approved paper set. Finalized record drawings are required before
the project will be accepted. E. A final stormwater site plan with letter shall be submitted by the Engineer of Record to the City verifying that the storm facilities were installed
as designed. F. Electronic copy of the Stormwater Site Plan and Geotechnical Report. The following documents shall also be completed for projects prior to project close out. A. All legal
documents, including but not limited to a Bill of Sale and Utility Easements, shall be updated as needed and executed. B. A “Developers Contribution Document” shall be obtained from
the City and completed, if applicable. C. All Maintenance Bonds or Assignments of Funds for the one-year maintenance period shall be in place.
Chapter 3 -Plan Preparation Requirements 3.00 Preface This chapter describes how civil engineering plans should be laid out to meet City requirements and provide a format that is easy
to follow and understand. Civil engineering plans need to meet these basic standards in order to move through the review process in an efficient manner. 3.01 General Requirements The
following general requirements shall be taken into account when preparing civil engineering plans for review and approval by the City: A. The general construction requirements for the
City of Auburn shall be those contained in the City of Auburn’s current Engineering Construction Standards Manual which supplements or modifies the “Washington State Department of Transportation
(WSDOT) Standard Specifications for Road, Bridge and Municipal Construction," except where supplemented or modified by the City in this manual. B. The civil engineering plans shall reference
City Standard Specifications and Standard Details as necessary. The City’s Standard Specifications and Standard Details are contained in the Engineering Construction Standards Manual,
a copy of which shall be on-site during construction. C. All civil engineering plans and reports shall be prepared and sealed by a Washington State licensed professional civil engineer.
D. Property surveys shall be performed and sealed by a Washington State licensed professional land surveyor and be tied to the current City datum (NAVD 88). A list of City Benchmarks
is available upon request. E. All civil engineering plans and calculations shall be neat, uncluttered, legible, and in conformance with the requirements herein. The City requires that
all plans be prepared utilizing AutoCAD software. F. Where applicable, shop drawings shall be submitted for review and approval prior to construction. 3.02 Plan Format The City requires
that plan sets be submitted in an order consistent with this section. Depending on the complexity or simplicity of the project, the amount of detail and content required will be subject
subject to change. 3.02.1 Grading Plans Grading plans shall consist of the following sheets: A. Cover sheet (See 3.04.1). B. Temporary Erosion and Sediment Control (TESC)/Demo Sheet
(Land Clearing when applicable) (See 3.04.2). 2/16/2010 Design Standards Page 3-01 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
C. Grading Plan (See 3.04.3). D. Cross-Sections (See 3.04.4). E. Details (See 3.04.5). 3.02.2 Building Site Plans Building Site Plans shall consist of the following sheets: A. Cover
Sheet (See 3.04.1). B. Temporary Erosion and Sediment Control (TESC)/Demo Sheet (Land Clearing when applicable) (See 3.04.2). C. Public Storm Drainage Plan (See 3.04.6). D. Utility Plan
(See 3.04.7). E. Cross-Sections (See 3.04.8). F. Details (See 3.04.5). G. Landscape Plan (See 3.04.10). H. Irrigation Plan (See 3.04.11). If a separate associated grading plan has been
submitted and approved, those areas covered under the grading plans will not need to be readdressed in the building site plans. 3.02.3 Facility Extension (FAC) Plans These plans will
be required whenever public streets, sanitary sewer, storm drainage, and/or water lines are being extended or modified. The FAC portion of a plan set could consist of the following sheets:
A. Cover Sheet (See 3.04.1). B. Temporary Erosion and Sediment Control (TESC)/Demo Sheet (Land Clearing when applicable) (See 3.04.2). C. Utility Plan and Profiles (See 3.04.7 & 3.04.8).
D. Street and/or Storm Plan and Profiles (See 3.04.8 & 3.04.9). E. Street Cross-Sections and Additional Street Elements (See 3.04.9). F. Details (See 3.04.5). G. Street and/or Site Landscape
Plans (See 3.04.10). FAC plans may also contain information normally associated with either a grading or a building site plan. 3.03 General Plan Requirements 3.03.1 Standard Plan Format
Applicable information in this section shall be shown on the plan set. A. Each sheet of the plan set shall be stamped by a professional engineer licensed in the State of Washington.
The stamp/seal on the final mylars, to be submitted for approval, shall be wet signed and dated per WAC 196-23. B. North arrow and plan alignment shall be to the top, right, or left.
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C. A title block shall be provided along the right-hand edge on each plan sheet. The title block shall include the development title (in bold print), the name, address and phone number
of the firm preparing the plan and the owner/developer, a revision block (showing the date of the latest revision), page of pages numbering, and sheet title (e.g., road and storm drainage,
grading, erosion/sedimentation control, water and sanitary sewer). D. Indicate units of measurement for all slope callouts as either percent (%) or feet per foot (ft/ft). Do not mix
units of measurement on a plan set. E. Provide all match lines with matched sheet numbers (stationing). F. The street classification shall be provided under the street name on all plan
views. G. A City of Auburn approval block (4"x2") on each plan sheet shall be provided in lower right corner of each plan sheet. Show project reference numbers (BLD for Building Permit,
FAC for Public Facility Extension Plan, LND for Land Clearing Permit, STM for Storm Permit and/or GRA for Grading/Erosion Control Permit) in the approval block area. A blank Auburn Engineering
approval block is shown as block B-1 in Appendix A of this chapter. H. A sign-off block (4”x2”) on each plan sheet shall be provided for Record Drawing certification, located directly
to the left or directly above the approval block. A blank Record Drawing Certification block is shown as block B-4 in Appendix A of this chapter. The locations of the title blocks, approval
blocks, and engineering stamp shall remain consistent throughout all the plan sheets. 3.03.2 Drafting Standards Drafting requirements are as follows: A. Plan sheets shall be printed
on 24"x36" size paper. Any variation must be approved by the City prior to plan submittal. Approved plans shall be good quality, 4-mil thickness, Mylar or approved equal. No stick-on
type material will be allowed. No Xerox, sepia, or toner-printed Mylars are allowed, unless cold rolled. Margins shall be set to provide for ½ size drawings to fit on 11x 17 inches sheet
sheet size. B. Lettering size shall be no smaller than one tenth (1/10) of an inch in height and shall be uppercase. Callouts and other information shall be printed horizontally in most
cases. C. Existing features shall be shown with dashed lines and/or half-toned (screened). D. Proposed features shall be shown with solid lines. The intent is to clearly distinguish
existing features from proposed improvements. 2/16/2010 Design Standards Page 3-03 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
E. Minimum scale shall be: 1. Site work: 1" = 40' horizontal. 2. Public facility work: 1" = 20' horizontal. Vertical scales should typically be 1/10th the horizontal scale. For public
facility work in areas with steep slopes, 1” = 5’ may be used in place of 1” = 2’. Use a scale that best utilizes paper space and gives the best overall view of the site. F. Use APWA
AutoCAD symbols in the legend to identify both existing and proposed improvements and utilities. 3.04 Plan Sheet Elements The following section covers the basic elements that are required
to be shown on the different plan sheets. While all plan sets will have a cover sheet, there are other sheets covered here that may or may not be included in a particular projects plan
set. 3.04.1 Cover Sheet The Title sheet(s) shall incorporate all the requirements listed in Section 3.02, plus the following applicable items: A. A general scaled site plan covering
an area approximately ten inches (10”) square. B. Vicinity map (approximate scale) with north arrow covering an area approximately five inches (5”) square. C. Site address. D. Owner/Applicant,
address, contact, and phone number. E. Engineer/Surveyor/Architect address, contact, and phone number. F. Elevations with City datum (NAVD 88) tied to City benchmarks with reference
to the benchmarks’ numbers and locations indicated. G. The permit number in one-inch (1”) bold lettering shall be above the title block (located on the right side of the sheet) on the
cover sheet only. H. Sheet Index. I. Legend. J. Legal description including quarter section, section, township, and range. K. Parcel numbers. L. Site zoning and adjacent zoning. M. Applicable
plat name and lot numbers. N. Applicable site information including the number of parking spaces required and the number of parking spaces provided. O. Type of building construction
as defined by the adopted Building Code. P. Site access including adjacent driveways, roadways, and intersections that may have an impact on the location and type of site access. 2/16/2010
Design Standards Page 3-04 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
Q. An overall site plan key map shall be shown if the plan set includes more than five (5) plan sheets, unless otherwise directed by the city. R. Construction Sequence outlining a basic
construction schedule. (See Section 5.05) In addition, depending upon the nature of the project, the construction of some public facilities may also dictate separate construction sequencing
requirements that will also need to be indicated on the plans. S. The eight (8) City of Auburn General Notes as shown in Appendix B of this chapter. T. Provide a list of the additional
non-building permits required for this project. 3.04.2 Temporary Erosion and Sediment Control (TESC) Plan Sheet TESC design shall be in accordance with Chapter 5 – Grading & Erosion
Control, and include the following applicable items: A. Marked clearing work limits, environmentally sensitive areas and their buffers, and trees that are to remain. B. Indicate the
location of the construction entrance C. Provide the onsite stormwater facilities during construction. D. Indicate the minimum temporary erosion control measures to be used on the site
during construction, this may include, silt fencing, interceptor ditches, detention or retention facilities, flow control structures, etc. E. Show containment locations for storing pollutants,
including waste materials and demolition debris, prior to their removal from site. F. In the construction sequence, provide a phasing schedule for installing and removing TESC BMPs,
including the transition from the temporary storm drainage system to the permanent storm drainage system. G. All existing site features and conditions shall be shown on this sheet including
the existing topography. H. This sheet may also function as a demolition site plan and should indicate all existing features and structures to be removed/demolished and those that will
remain. I. Provide the six (6) City of Auburn Grading and Erosion Control Notes as shown in Appendix B of this chapter. 3.04.3 Grading and Private Storm Drainage Plan Sheet The Grading
design shall be in accordance with Chapter 5 – Grading & Erosion Control, and include the following applicable items: A. Indicate approximate fill and excavation quantities in cubic
yards. B. Indicate slope of any fill or cut slopes. C. Show type of fill material and associated compaction requirements. D. Show existing significant trees (six inches (6”) in diameter
and larger for evergreens and four inches (4”) in diameter or larger for deciduous). Indicate if tree is to either be retained or removed. Note that a land-clearing permit may be required.
2/16/2010 Design Standards Page 3-05 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
E. Provide temporary storm drainage retention or detention facilities including City control structure, water surface (W.S.) elevations, seasonal high groundwater elevation, orifice
sizes, design storms for the W.S. elevations, and release rates. F. Show horizontal setback between the bottom of any fill placement and the top of the bank of a defined drainage channel
per requirements noted in section 5.03.3. G. Show typical ditch sections. H. Show connections of building roof and foundation drains to the site drainage system. I. Show the existing
topography shaded back and overlaid by the proposed grades. J. Show existing and finished elevations and contours. Spot elevations may be required for relatively flat sites to supplement
the contour elevations as necessary to adequately reflect existing and finish grades. Provide spot elevations along property line and a minimum of thirty feet (30’) beyond property line
(at least fifty foot (50’) intervals). K. Reference standard City of Auburn Detail Numbers appropriately. If a project specifies modification to a Standard Detail a new detail must be
shown on the plans. L. Provide notes to protect and maintain erosion control facilities during grading operations. M. Provide arrows to indicate drainage flow direction on paved surfaces.
N. Show layout of the entire storm drainage pipe with length, slope, and material type labeled and direction of flow indicated. O. Provide site specific details and cross-section sheets
for storm drainage detention or retention facilities. P. Indicate the emergency overflow to the public storm system. Q. Show berm dimensions, materials, compaction requirements for ditches
and detention ponds where applicable. R. Show locations of manholes and catch basins, indicating type, stationing, offset, lid type, rim and invert elevations. Number manholes and catch
basins consecutively. S. Show existing and proposed sanitary sewers and water
mains (use ghost lines), identifying crossing and minimum vertical distance between utilities. T. Provide type of material and size of energy dissipaters (riprap, etc.). U. Provide details
of storm water quality control facility. V. Provide limits of surface water ponding in parking lots. W. Show trash racks, if applicable. X. Show locations, widths and types of easements.
Y. Show locations and types of pumps, if applicable. Z. Show bio-swale location, length, width, slopes, and cross-section. AA. Provide planting and seeding requirements with establishment
procedure in construction sequence for water quantity and quality systems. 2/16/2010 Design Standards Page 3-06 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
BB. Show finish floor elevations. CC. Show the controlling downstream storm drainage elevations including the associated design conditions. DD. Address other agency permit requirements,
as necessary. EE. For ponds, provide: aesthetics, fencing, power (if applicable), maintenance access, control structure, critical water surface elevations, and other items, such as walls
and liners. FF. Address bypass surface flows. GG. Address subsurface flows and indicate water surface elevations. HH. Clearly indicate private drainage facilities on the plans. Justification
is needed for any facility proposed to be a joint public and private facility, for City consideration. Some projects may be able to combine the grading sheet with the erosion control
and demo plan depending on the complexity of the project. 3.04.4 Cross-Section Sheet The Cross-Section plan sheet(s) shall have the following applicable items: A. Cross-sections for
fill and grading shall be shown through all properties to at least thirty feet (30’) beyond the property lines. Adequate cross-sections shall be shown to represent the site. At a minimum
this shall include one east-west and one north-south cross-section. B. This sheet may also contain cross-sections for the temporary storm drainage pond. C. The scale used for the site
cross-sections on this sheet should match the scale on the other sheets. Some projects may be able to combine the cross-section sheet with the grading sheet depending on the complexity
of the project. 3.04.5 Detail Sheet The Detail sheet(s) shall have the following applicable items: A. Any detail that is specific to this project. B. City Standard Details should not
be shown on this sheet unless they need to be modified for a project specific application. C. Storm control manholes are normally shown on this sheet. D. This sheet may also contain
cross-sections for the temporary storm pond. City Standard Details should be called out on the applicable plan sheet using the detail number. 3.04.6 Public Storm Drainage Plan Sheet
Grading and Storm Drainage system design shall be in accordance with Chapter 5 – Grading & Erosion Control, and Chapter 6 – Storm Facilities, and include the following applicable items:
A. The layout of all the storm drainage pipes with the length, slope, and material type indicated in the labeling of the storm drainage pipes. Provide arrows to indicate the direction
of flow into the structures. 2/16/2010 Design Standards Page 3-07 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
B. Typical ditch section. C. Location of manholes and catch basins. Indicate type, stationing, offset, rim and invert elevations, and number manholes and catch basins consecutively.
D. Existing and proposed sanitary sewers and water mains (use ghost lines). Identify crossings and minimum distance between utilities. E. Building downspouts or footing drain locations,
inverts and connections to the storm drain system. F. For single-family home sites, indicate means for collection and discharge of water from roof, foundation drains, and driveways.
G. Provide arrows to indicate drainage direction in parking lots, roadway intersections and cul-de-sacs. H. Reference to the detail/BMP and/or cross-section sheets for storm drainage
detention or retention facilities such as the control discharge structure and pond cross-sections. Indicate water surface elevations, allowable discharge rates, and design storms. I.
Show an emergency overflow to the public storm drainage system. J. Berm dimensions, material, and compaction requirements for ditches and detention ponds where applicable. K. Indicate
type of material and size of energy dissipaters (riprap, etc.). L. Provide details of the storm drainage water quality facility. M. Limits of surface water ponding within parking lots.
N. Trash racks as applicable. O. Location and widths of easements. P. Location and type of pumps, if applicable. Q. Bioswale location, length, width, slopes, and cross-section. R. Planting
and seeding requirements with establishment procedure (construction sequence) for water quantity or quality systems. S. Finish floor elevations of all buildings. T. Indicate separation
from any pipe, infiltration trench, open ditch, and bioswale to any property line or obstruction. U. Address other agency permit requirements, as necessary. V. For ponds, provide: landscaping,
fencing, aeration, maintenance access, critical water surface elevations, and other items, such as walls and liners. W. Number the storm drain structures. (Numbers will be provided by
the City prior to final plan approval.) X. Indicate any required easements including their dimensions. 3.04.7 Utility Plan Sheet The Utility sheet will show the private connections to
the public water and sanitary sewer systems and any required extensions of the public water and sanitary sewer systems. The Utility sheet(s) shall have the following applicable items:
2/16/2010 Design Standards Page 3-08 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
3.04.7.1 Water Water system design shall be in accordance with Chapter 7 – Water Facilities, and include the following items: A. Water pipe and fitting size, location, and type of material.
B. Details of connections to existing water mains. C. Valve size, locations and type. D. Fire hydrants locations. E. Air vac/blow-off locations. F. Pressure reducing stations and associated
valves, vaults and by-pass piping as required. G. Concrete blocking, mechanical, or restrained joint pipe support. H. Watermain, water meter, and fire hydrant easements. I. Meter size
and service line size and location. J. Irrigation meter size and service line size location. K. Proposed fire line, FDC line and PIV locations. L. Backflow prevention assembly and detector
check meter size, type and location. M. For buildings requiring fire sprinklers, the fire sprinkler notes shall be shown on the plan, as shown in Appendix B of this chapter. N. Table
showing physical separation in feet between water lines and other utilities at crossings, when a profile is not required. 3.04.7.2 Sanitary Sewer Sanitary sewer system design shall be
in accordance with Chapter 8 – Sanitary Sewer Facilities, and include the following items: A. Sanitary sewer pipe size, locations, type of material, and stationing. B. Location of manholes.
Indicate type of manhole, stationing, offset, and number manholes consecutively. During the City review process, manhole numbers shall be assigned by the City to be incorporated into
the next submittal. C. Indicate knockouts in manholes for future connections. D. The direction of sewage flow shall be indicated with an arrow at the manhole. Proposed sewer shall have
solid arrowheads while existing pipe and manholes shall be shown in ghost or screened lines with the arrowhead and manhole not filled. E. Drop manholes, if approved, are to be detailed
on the plans. F. Length, slope, type and class of material, and inverts for side sewers. G. Stationing for side sewers from downstream manholes. H. Connection of a side sewer to the
City’s sanitary sewer pipe shall be indicated with a tee. I. Locations of sanitary sewer cleanouts. 2/16/2010 Design Standards Page 3-09 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter
3 (2-10)
J. Locations of sanitary sewer easements. K. Clearly define right-of-way and adjacent property lines. Parcel numbers for all lots adjacent to the improvements shall be indicated. L.
Floor drains, drains from other covered areas potentially subject to pollutants, and wash areas within parking lots shall be connected to the sanitary sewer through an approved oil/water
separator. 3.04.8 Utility Profile Sheet The Utility Profiles, when required, should be included on the associated utility plan sheet if at all possible. 3.04.8.1 Storm Drainage For complex
private storm systems and all public storm lines, a profile will be required. These profiles should include the following items where applicable: A. Public storm drainage located within
the street right-of-way shall be shown on the street profile. See Section 3.04.9.2 B. Public storm drainage located in an easement shall have separate profiles. C. Structure size, location,
type, station, invert elevation, type of lid or grate, and rim elevation. D. Pipe size, type of material, slope (ft/ft), and lineal footage. E. Utility crossings shall identify size
and type of utilities involved. F. Ditches where applicable, size, type and slope. G. Existing and finished grade along pipe centerline. H. Connections to existing structures. 3.04.8.2
Water For complex on-site public water systems and all public water mains within the street, a profile will be required. These profiles should include the following items where applicable:
A. Water line located within the street right-of-way shall be shown on the street profile. See Section 3.04.9.2. B. Water line profiles are not generally required for lines located in
easements unless there are utility conflicts. C. Pipe size, type of material, lineal footage, cover and stationing. D. Utility crossings shall identify size and type of utility involved.
E. Existing and finished grade along pipe centerline. F. Connections to existing mains and fittings. G. Label fittings and valves include blocking. 3.04.8.3 Sanitary Sewer A profile
will be required for all public sanitary sewer mains. These profiles should include the following items where applicable. A. Sanitary sewer located within the street right-of-way shall
be shown on the street profile. See Section 3.04.9.2 2/16/2010 Design Standards Page 3-010 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
C. Structure size, location, type, station, invert elevations, type of lid, and rim elevation. D. Pipe size, type of material, slope (ft/ft), and lineal footage. E. Utility crossings
shall identify size and type of utility involved. F. Existing and finished grade along pipe centerline. G. Connections to existing structures. H. Side sewer locations and stationing.
3.04.9 Public Street Plan and Profile Sheet Whenever a project includes construction within a public street excluding utility connections, both a plan and a profile shall be included
in the plan set. The Public Street Plan and Profile sheet(s), when required, shall have the following applicable items: 3.04.9.1 Plan View The plan view should include the following
items where applicable: A. Plan views shall be drawn at a 1" = 20' scale. B. Existing and proposed rights-of-way. C. Existing and proposed contours and elevations. D. Existing and proposed
street names. E. Existing and proposed centerline bearings. F. Existing and proposed signs and traffic traffic control devices. G. Existing and proposed storm drainage systems. H. Existing
and proposed sewers and water mains (use ghost lines). Identify crossings and minimum distances between utilities. I. Horizontal curves. J. Horizontal stationing. K. Location of curbs,
sidewalks, wheelchair ramps, and driveways (by station). L. Locations of monuments at all centerline intersections, cul-de-sacs, PCs, and PTs by station. M. Street luminaires, conduit
for streetlights, traffic signals, and traffic signal loop detectors located within the vicinity of the project. N. Mailbox types and locations. Submit to postmaster for approval. O.
Address any horizontal utility conflicts in plan. P. Street landscaping, if required. Q. Construction limits. R. Slope excavation and/or embankment limits. 3.04.9.2 Profile The profile
should include the following items where applicable: A. Profiles shall be drawn using 1" = 20' horizontal and 1" = 2' vertical scales. 2/16/2010 Design Standards Page 3-011 REF. H:\DEVELOPMENT\Manual
s\Design Standards\Chapter 3 (2-10)
2/16/2010 Design Standards Page 3-012 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10) B. Existing and proposed centerline road grade. C. Existing and proposed storm drainage
systems. D. Existing and proposed sewers and water mains (use ghost lines). Identify crossings and minimum distances between utilities. C. Finish grade elevations every fifty feet (50’)
and every twenty-five feet (25’) for vertical curves along design centerlines. D. Vertical curve information in profile section. E. Address vertical utility conflicts in profile. 3.04.9.3
Intersections Intersection plans shall be twenty (20) scale drawings in conformance with Standard Detail TRAFFIC-13. 3.04.9.4 Typical Roadway Sections Typical roadway sections shall
show pavement depths, widths and materials, cross-slopes of pavement (%), centerline, dimensioned right-of-way lines, curb and gutter, ditches, embankment and excavation slopes (1:1),
rockers, walls, etc. Typical sections will be labeled within identified station ranges. 3.04.9.5 Striping and Signing Provide forty (40) scale plans per these Standards and MUTCD, including
lane markers, pavement markings, and signing. 3.04.9.6 Signalization Provide twenty (20) scale separate detailed signalization plan per City of Auburn Standards, including poles, bases,
conduits, and traffic loops. A. Signal Plan Sheet 1. The plan sheet shall conform to the following requirements: a. For areas that require greater detail (such as the corner that has
the controller), a blown-up detail may be necessary at a 1″=10′ scale. b. All proposed signal equipment, including signal poles, mast arms, heads, signs, junction boxes, conduit, loops,
controller, and service cabinet shall be shown as bold. c. All existing and proposed right-of-way information shall be shown and labeled on the plan, including easements needed for signal
equipment. The line type shall be different for easements and right-of-way. d. All proposed curb, sidewalk, proposed striping, and existing curb/striping (to remain) information shall
be shown on the plan in gray scale (screened back). e. Sight triangle lines shall be shown on plans in gray scale. f. All proposed and existing underground and overhead utilities shall
be shown and labeled on the plan in gray scale. g. Provide on the plan signal construction notes as shown in Appendix B of this chapter.
2. Construction notes shall contain, but not be limited to: a. Signal pole and foundation installation (including pole type, mast arm length, and installation of items on the pole).
b. Controller cabinet and foundation installation. d. Coordination of utility removal/relocation. e. Coordination of connection of power, and power source type. f. Interconnect connection
to other signals. g. Removal of existing signal and/or street light equipment. 3. Displays: The plan sheet shall include the following displays: a. Phase diagram display. b. Signal display
showing signal layout of all vehicle signal heads and pedestrian heads. 4. Detection: The plan sheet shall include: a. Stop bar, intermediate and advanced loop location and numbering.
b. Pedestrian push button location. c. Preemption detection location and numbering. 5. Signal Poles and Associated Equipment: The plan sheet shall contain, but not be limited to: a.
Signal Pole Locations and Numbering: The locations shall be called out by the major arterial station and offset. b. Signal head location and numbering. c. Pedestrian head location and
numbering. 6. Controller and Service Location: At least one corner of the controller/service foundation shall be called out by the major arterial station and offset. The footprint of
the foundation shall be shown on the plans with the controller and service cabinets oriented on the foundation as they would be placed in the field. If the information required to show
all the controller/service conduit connections and foundation footprint makes the plan too cluttered, a blown-up detail of the corner containing this information is needed at a 1″=10′
scale. 7. Power Source Location: The location of the power source shall be identified on the plans. 8. Wire Schedule: a. A wire schedule table shall include run numbers, conduit size,
wire type, and comments. b. Comments shall include, but not be limited to, number of twisted loop pairs for runs between the detection loops and adjacent junction box, identification
of spare conduits, conduits utilized only by interconnect or illumination, and power cables. c. For designs that include modifications to an existing signal, all existing wire runs affected
by the design shall be shown on the wire schedule. 2/16/2010 Design Standards Page 3-13 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
9. Junction box type and approximate location. 10. Signing: a. Signs shall be shown on all mast arms. Signs that are post mounted but are signal related (such as a “signal ahead” sign)
shall be shown on the signal plan. b. A sign display shall be shown on the plan with the MUTCD sign designation, dimensions, and lettering type for all signs. c. Indicate removal of
existing stop signs after signal is in operation. d. Installation of “New Signal Ahead” or “Signal Revision Ahead” signs. 11. Other Illumination: a. Proposed illumination that will use
the signal service cabinet, but is located outside the four quadrants of the intersection, shall be shown as proposed on a separate illumination plan sheet. On the signal plan sheet,
the illumination shall be shown as gray scale and labeled as “proposed illumination, see illumination plans.” However, once the illumination enters the quadrants of the intersection
(i.e., when it is using the same junction box as the signal equipment), it shall be shown as proposed on the signal plan and gray scale on the illumination plan. b. Indicate the circuit
that street lights are on . B. Wire Diagram Plan In general, the wire diagram shall include the following: 1. All signal heads, pedestrian heads, pedestrian push buttons, luminaires,
preemption detectors, loops, and junction boxes drawn in schematic forms. 2. All termination points in the controller cabinet. The wire diagram should include every termination point
the controller will have, including those that may not be used for this particular signal design. 3. All wiring associated with the items above, as well as the wiring for interconnect.
The wire diagram should show how these items are connected to the controller. 4. Location of wire splices. 5. All termination numbering at each end of each wire. For example, the 5-conductor
cable connecting a signal head to the controller should have the termination numbering called out at the signal head and in the termination points in the controller. 6. All wire colors
at each end of the wire. 7. A call out to each wire run noting the number and type of each wire. 8. Intersection schematic with a north arrow showing approach phase. 9. Pole, signal
head, pedestrian head, preemption detection, and loops shall be numbered on the wire diagram. C. Pole Schedule Plan 2/16/2010 Design Standards Page 3-14 REF. H:\DEVELOPMENT\Manuals\Design
Standards\Chapter 3 (2-10)
The pole schedule shall include the following: 1. The pole schedule shall include a signal standard detail chart. 2. The pole schedule shall include pole orientation attachment and base
detail, pole foundation detail, and signal standard detail. 3.04.9.7 Illumination Street Light Plans shall be labeled as Street Light Plans, and shall be prepared, stamped, signed and
dated by a professional engineer licensed by the State of Washington. Street Light Plans will include references to all applicable City of Auburn Standard Details and/or Washington State
Department of Transportation (WSDOT) Standard Plans, or copies of other specific details applicable to the project shall be shown on the plans. Street Light Plans shall be provided on
separate and uncluttered sheets that do not show unrelated street, utilities, or on-site improvements. Street Light Plans shall be drawn to an engineer's scale of 1" = 40'. Street Light
Plans shall at a minimum include the following applicable items for new or existing street lighting system: A. Lighting schedule with the following information in a table format: 1.
Luminaire make and model 2. Lamp/Ballast type 3. Lamp wattage 4. Uniformity Ratio 5. Veiling Luminance Ratio 6. Average Maintained Light Level 7. Light standard type 8. Mounting height
(ft) 9. Bracket or davit arm length (ft) 10. Light distribution pattern 11. Luminaire spacing distance (ft) 12. Light standard locations by station and offset from the centerline of
the street to the center of the light standard. Show all existing street lights for a distance of 500 feet in both directions from the limits of the project site, including both sides
of the street(s) and in medians. 2/16/2010 Design Standards Page 3-15 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
B. Wiring/Conduit schedule with the following information in a table format: 1. Circuit number 2. Conduit size, material, and purpose (street lighting, traffic signal interconnect, spares,
etc.). C. Location of points of service (the PSE connection or service location and the new or existing City Electrical Service Cabinet(s). D. Location of junction boxes. Indicate junction
box type and purpose (lighting, traffic signal, etc.). E. Existing topography, including but not limited to the location of driveways, street trees (including species), street intersections,
overhead utilities (including maximum and minimum heights), underground utilities (including sizes), medians, curb, and lane widths (pavement markings). 3.04.9.8 Streetscape Provide
information on planting of the public landscape strips along the street frontage. Information should include the following: A. Type and size of trees. B. Tree spacing. C. Type of ground
cover. D. Root control/barrier. E. Irrigation if applicable. F. Show all proposed and and existing surface features and underground utilities. 3.04.9.9 Other Features Include locations
of any other feature including mailboxes and bus stops. Any mailbox placement that requires approval from the postmaster shall include the Postmaster approval block B-6 as shown in Appendix
A of this chapter. 3.04.10 Site Landscape Plan Sheet The site landscape sheets, when required, shall have the following applicable items: A. Adjacent streets both public and private.
B. Have boundaries and dimensions of site. C. The location of on-site buildings. D. The location of on-site parking areas. E. The location and size of landscape areas. F. The location,
species, and size of planting materials. G. The location of outdoor storage areas. H. The location of significant trees. I. Show all proposed and existing surface features and underground
utilities. J. The Planning approval block B-2 as shown in Appendix A of this chapter. 2/16/2010 Design Standards Page 3-16 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 3 (2-10)
3.04.11 Site Irrigation Plan sheet The site irrigation sheets, when required, shall have the following applicable items: A. The connection point to the City system. B. The size, location,
and type of the backflow prevention. C. The proposed layout of the irrigation system. D. Be consistent with the site’s building and landscaping plans. E. Show the existing and/or proposed
location of all parcel lines. 3.04.12 Critical Area Restoration/Mitigation A critical area restoration or mitigation sheet, when required, shall include the items as required by the
City pursuant to chapter 16.10 of the Auburn City Code, and have the Critical Area approval block B-3 as shown in Appendix A of this chapter. 3.04.13 City Parks and Open Spaces Any plan
sheet that includes a park or open space that is to be dedicated to the City shall include the Auburn Parks approval block B-5 as shown in Appendix A of this chapter. 2/16/2010 Design
Standards Page 3-17 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
Appendix A – Approval Blocks Sample Engineering Approval Block (B-1): PROJECT REF: __________________________ THESE PLANS ARE APPROVED FOR CONFORMANCE WITH THE CITY OF AUBURN’S ENGINEERING
REQUIREMENTS. APPROVED BY: _________________________ DATE APPROVED: _______________________ Sample Planning Approval Block (B-2): PROJECT REF: _________________________ THESE PLANS ARE
APPROVED FOR CONFORMANCE WITH THE CITY OF AUBURN’S PLANNING DEPARTMENT REQUIREMENTS. APPROVED BY: _________________________ DATE APPROVED: ______________________ Sample Critical Area
Approval Block (B-3): PROJECT REF: _________________________ THESE PLANS ARE APPROVED FOR CONFORMANCE WITH THE CITY OF AUBURN’S CRITICAL AREA REQUIREMENTS. APPROVED BY: _________________________
DATE APPROVED: ______________________ 2/16/2010 Design Standards Page 3-18 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
Appendix A (continued) Sample Record Drawing Certification Block (B-4): RECORD DRAWING CERTIFICATION THESE DRAWINGS CONFORM TO THE CONTRACTOR’S CONSTRUCTION RECORDS. BY _______________________
DATE ___________ TITLE/POSITION _____________________________ CONFIRMED BY CITY ____________ DATE _______ Sample Parks Department Approval Block (B-5): PROJECT REF: _________________________
THIS PLAN SHEET REFLECTS THE CITY OF AUBURN PARKS DEPARTMENT MINIMUM REQUIREMENTS APPROVED BY: _________________________ PARKS DIRECTOR DATE APPROVED: ______________________ Sample Postmaster
Approval Block (B-6): CITY OF AUBURN POSTMASTER APPROVAL APPROVED BY: ________________________ TITLE/POSITION: _______________________ DATE APPROVED: ______________________ 2/16/2010
Design Standards Page 3-19 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
Appendix B – Standard Notes GENERAL NOTES 1. THIS DEVELOPMENT PROJECT SHALL CONFORM TO THE CITY OF AUBURN’S REQUIREMENTS AND BE IN ACCORDANCE WITH THE APPROVED PLANS. ANY CHANGES FROM
THE APPROVED PLAN WILL REQUIRE APPROVAL FROM THE OWNER, ENGINEER, AND THE CITY. 2. ALL WORKMANSHIP AND MATERIALS SHALL CONFORM TO THE “WASHINGTON STATE DEPARTMENT OF TRANSPORTATION (WSDOT)
STANDARD SPECIFICATIONS FOR ROAD, BRIDGE, AND MUNICIPAL CONSTRUCTION (2008),” EXCEPT WHERE SUPPLEMENTED OR MODIFIED BY THE CITY’S CONSTRUCTION STANDARDS MANUAL. COPIES OF THE ABOVE DOCUMENTS
SHALL BE AVAILABLE AT THE JOB SITE DURING CONSTRUCITON. 3. A PRE-CONSTRUCTION MEETING SHALL BE REQUIRED PRIOR TO THE START OF ALL CONSTRUCTION. CONTACT THE PUBLIC WORKS DEPARTMENT AT
253-931-3010, TO SCHEDULE A MEETING. 4. LOCATIONS SHOWN FOR EXISTING UTILITIES ARE APPROXIMATE. THE CONTRACTOR IS CAUTIONED THAT OVERHEAD UTILITY LINES MAY NOT BE SHOWN ON THE DRAWINGS.
IT SHALL BE THE CONTRACTOR’S RESPONSIBILITY TO DETERMINE THE TRUE ELEVATIONS AND LOCATIONS OF ALL UNDERGROUND UTILITIES AND THE EXTENT OF ANY HAZARD CREATED BY OVERHEAD UTILITY LINES.
IDENTIFICATION, LOCATION, MARKING, AND RESPONSIBILITY FOR UNDERGROUND FACILITIES OR UTILITIES, IS GOVERNED BY THE PROVISIONS OF CHAPTER 19.122 REVISED CODE OF WASHINGTON (RCW). PRIOR
TO STARTING CONSTRUCTION, THE CONTRACTOR SHALL CALL ONE-CALL (1-800-424-5555) FOR UTILITY LOCATIONS (WATER, SANITARY SEWER, STORM SEWER, GAS, POWER, TELEPHONE, AND CABLE). 5. IF A PROPOSED
ROUTE IS NOT INCLUDED ON THESE PLANS, A PROPOSED ROUTE AND SCHEDULE FOR HAULING MATERIAL TO THE SITE SHALL BE SUBMITTED TO THE CITY FOR APPROVAL PRIOR TO THE START OF CONSTRUCTION. IF
THE CITY BELIEVES THAT THE PROPOSED HAUL ROUTE WILL ADVERSELY IMPACT THE STREET NETWORK, A SEPA AMENDMENT MAY BE REQUIRED TO EVALUATE THE IMPACTS AND DETERMINE MITIGATION REQUIREMENTS
BEFORE BEGINNING WORK. HAULING MAY BE LIMITED TO APPROPRIATE OFF-PEAK HOURS OR ALTERNATIVE ROUTES, AS DETERMINED BY THE CITY. 6. THE CONTRACTOR SHALL BE RESPONSIBLE FOR PUBLIC SAFETY
ON AND AROUND THE PROJECT. PRIOR TO THE START OF WORK, ALL METHODS AND EQUIPMENT USED FOR TRAFFIC CONTROL AND STREET MAINTENANCE SHALL BE SUBMITTED TO THE CITY FOR APPROVAL. CONTRACTORS
AND THEIR SURETY SHALL BE LIABLE FOR INJURIES AND DAMAGES TO PERSONS AND PROPERTY SUFFERED BECAUSE OF CONTRACTORS OPERATIONS OR NEGLIGENCE CONNECTED WITH THEM. 7. ALL CONSTRUCTION SURVEYING
FOR EXTENSIONS OF PUBLIC FACILITIES SHALL BE DONE UNDER THE DIRECTION OF A WASHINGTON
LICENSED LAND SURVEYOR OR A WASHINGTON LICENSED PROFESSIONAL CIVIL ENGINEER. 8. CERTIFIED DRAWINGS ARE REQUIRED PRIOR TO PROJECT ACCEPTANCE. REFER TO THE CITY’S “RECORD CONSTRUCTION
DOCUMENT” HANDOUT. 2/16/2010 Design Standards Page 3-20 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
Appendix B (continued) GRADING AND EROSION CONTROL NOTES 1. WITHIN THE CITY OF AUBURN, ALL REQUIRED SEDIMENTATION AND EROSION CONTROL FACILITIES INDICATED ON THE PLANS MUST BE CONSTRUCTED
AND IN OPERATION PRIOR TO LAND CLEARING AND/OR OTHER CONSTRUCTION ACTIVITIES. THESE FACILITIES SHALL BE MAINTAINED AND UPGRADED, IF NECESSARY, TO INSURE THAT SEDIMENT-LADEN WATER AND
STORM DRAINAGE RUNOFF DOES NOT IMPACT THE ADJACENT PROPERTIES, NATURAL DRAINAGE WAYS, OR THE EXISTING CITY STORM DRAINAGE SYSTEM. 2. THE SOURCES FOR ALL MATERIAL IMPORTED TO THE SITE
SHALL BE APPROVED BY THE CITY. 3. THE STORM DRAINAGE DETENTION (RETENTION IF INFILTRATION SYSTEM IS USED), SEDIMENTATION AND EROSION CONTROL FACILITIES DEPICTED ON THE APPROVED DRAWINGS
ARE INTENDED TO BE MINIMUM REQUIREMENTS TO MEET ANTICIPATED SITE CONDITIONS. ADDITIONAL DRAINAGE AND EROSION CONTROL FACILITIES MAY BE REQUIRED AS SITUATIONS WARRANT DURING CONSTRUCTION.
THE IMPLEMENTATION, MAINTENANCE, REPLACEMENT AND ADDITIONS TO THESE CONTROL SYSTEMS SHALL BE THE RESPONSIBILITY OF THE PERMITEE. 4. THE TEMPORARY EROSION CONTROL FACILITIES, INCLUDING
ALL PERIMETER CONTROLS AND THE DETENTION (RETENTION IF INFILTRATION SYSTEM IS USED), CONTROL PONDS, SHALL REMAIN IN PLACE UNTIL FINAL SITE CONSTRUCTION IS COMPLETED. AFTER CITY APPROVAL,
THE CONTRACTOR WILL BE RESPONSIBLE FOR REMOVING ALL TEMPORARY FACILITIES. 5. THE CONTRACTOR WILL BE REQUIRED TO WATER THE SITE, AS NECESSARY, TO REDUCE DUST EMISSIONS AS A RESULT OF
CONSTRUCTION ACTIVITY. THE CONTRACTOR SHALL ALSO SWEEP ALL AFFECTED PUBLIC ROADS, AS NECESSARY, TO REMOVE MATERIAL DEPOSITED AS A RESULT OF PROJECT CONSTRUCTION ACTIVITY. 6. ALL AREAS
OF ACTIVE EARTHWORK WHICH HAVE THE POTENTIAL FOR EROSION AND SEDIMENTATION IMPACTS ON ADJACENT PROPERTIES, NATURAL DRAINAGE WAYS, OR THE EXISTING CITY STORM DRAINAGE SYSTEM MUST BE STABILIZED
ACCORDING TO THE FOLLOWING SCHEDULE: FROM MAY 1ST TO SEPTEMBER 30TH, AREAS AT FINAL GRADE AND THOSE THAT ARE SCHEDULED TO REMAIN UNWORKED FOR MORE THAN SEVEN (7) DAYS SHALL BE STABILIZED.
FROM OCTOBER 1ST TO APRIL 30TH EARTHWORK ACTIVITIES SHALL BE CONDUCTED IN STAGES IN ORDER TO MINIMIZE SOIL EXPOSURE. EXPOSED SOILS WITH AN AREA GREATER THAN 5,000 SQUARE FEET THAT ARE
SCHEDULED TO REMAIN UNWORKED FOR MORE THAN 24 HOURS AND EXPOSED AREAS OF LESS THAN 5,000 SQUARE FEET THAT WILL REMAIN UNWORKED FOR MORE THAN TWO (2) DAYS SHALL BE STABILIZED IMMEDIATELY.
2/16/2010 Design Standards Page 3-21 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
Appendix B (continued) FIRE SPRINKLER SYSTEMS NOTES SPRINKLER SYSTEMS SHALL MEET CITY OF AUBURN STANDARD 7.01.5.2 AND THE FOLLOWING REQUIREMENTS: 1. PROPOSED FIRE LINE TO BE SIZED BY
A FIRE PROTECTION ENGINEER. 2. BACKFLOW PROTECTION IS REQUIRED ON FIRE SPRINKLER LINES 3. A SEPARATE DETAILED PLAN OF THE UNDERGROUND FIRE SPRINKLER SUPPLY LINE SHALL BE APPROVED BY
THE FIRE MARSHALL AND INSTALLED BY A WASHINGTON STATE CERTIFIED LEVEL “U” CONTRACTOR IN ACCORDANCE WITH WAC 212-80-010. 4. A POST INDICATOR VALVE SHALL BE INSTALLED ON THE FIRE SPRINKLER
SUPPLY LINE TO ISOLATE THE SYSTEM FROM THE CITY’S WATER SYSTEM WHEN REQUIRED FOR REPAIR. 5. BLOCKING, PIPING, AND RODDING DETAILS SHALL BE PROVIDED WITHIN THE SUBMITTAL. 6. APPROVAL
OF THE CIVIL PLANS DOES NOT APPROVE THE INSTALLATION OF THE SPRINKLER SYSTEM SUPPLY PIPING. CROSS CONNECTION CONTROL NOTES CROSS CONNECTION CONTROL SHALL MEET THE FOLLOWING REQUIREMENTS:
1. ALL BACKFLOW PREVENTION ASSEMBLIES SHALL BE INSTALLED IN A MANNER THAT WILL ALLOW PROPER OPERATION, AND IN-LINE TESTING AND MAINTENANCE.. 2. A BACKFLOW ASSEMBLY PLUMBING PERMIT IS
REQUIRED FOR ALL ASSEMBLIES INSTALLED WITHIN THE CITY OF AUBURN, AND/OR THE CITY’S WATER DISTRIBUTION SYSTEM. 3. BACKFLOW ASSEMBLIES MUST BE ON THE CURRENT WASHINGTON STATE DEPARTMENT
OF HEALTH – BACKFLOW ASSEMBLIES APPROVED FOR INSTALLATION LIST. 4. BACKFLOW ASSEMBLIES MUST BE TESTED BY A STATE CERTIFIED BACKFLOW ASSEMBLY TESTER, AND INSPECTED AND APPROVED BY A CITY
OF AUBURN CROSS CONNECTION CONTROL SPECIALIST. 5. PRIOR TO INSTALLATION, SUBMIT TO THE DEVELOPMENT REVIEW ENGINEER FOUR (4) SETS OF BACKFLOW PREVENTION ASSEMBLY PLANS, INCLUDING THE
CONNECTION POINT TO THE CITY MAIN FOR REVIEW AND APPROVAL. 2/16/2010 Design Standards Page 3-22 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10)
2/16/2010 Design Standards Page 3-23 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 3 (2-10) Appendix B (continued) SIGNAL CONSTRUCTION NOTES 1. THE LOCATION OF ALL CONDUIT, JUNCTION
BOXES, AND CABINETS SHOWN ON THIS PLAN ARE FOR GRAPHIC PRESENTATION ONLY AND FINAL LOCATION SHALL BE DETERMINED BY THE ENGINEER. 2. ALL TRAFFIC SIGNAL AND PEDESTRIAN HEADS AND PUSH BUTTONS
SHALL BE SECURELY AND COMPLETELY COVERED WHILE SIGNAL IS NOT IN OPERATION. 3. ALL CONDUCTORS FOR SIGNAL HEADS, LOOPS, PEDESTRIAN HEADS, PUSH BUTTONS AND STREETLIGHTS SHALL BE LABELED
IN EACH JUNCTION BOX.
Chapter 4 – Report Preparation Requirements 4.00 Preface This chapter describes how technical engineering reports should be laid out to meet City requirements and provide a format that
is easy to follow and understand. Reports need to meet these basic standards in order to move through the review process in an efficient manner. 4.01 General Requirements The following
general requirements shall be met for all technical engineering reports being submitted for review and approval: A. All reports and calculations shall be prepared, stamped, signed, and
dated by a Washington State licensed professional civil engineer. B. All reports and calculations shall be neat, uncluttered, legible, and in conformance with the requirements herein.
C. All engineering reports shall be bound with the civil engineer’s stamp clearly visible. D. Reports shall reference City Standards as necessary. 4.02 Report Types The following are
basic types of reports submitted as supporting project information. Depending on the complexity or simplicity of the project and its location, the amount of detail, and the number and
types of reports required will be subject to change. The examples given are the typical reports required for a standard project, there may be other reports required that are specific
to a particular project. A. Geo-Technical Reports See Section 4.03.1 B. Stormwater Site Plans See SWMM Volume 1 Ch. 4 C. Critical Area Report See Section 4.03.3 D. Traffic Impact Analysis
See Section 4.02.4 4.03 Report Requirements 4.03.1 Geo-Technical Reports The geo-technical report format shall include the following applicable items: A. Title page including project
name and address. B. General information, which includes existing site conditions. C. Site history including any prior grading. 2/16/2010 Design Standards Page 4-01 REF. H:\DEVELOPMENT\Manuals\Design
Standards\Chapter 4 (2-10)
D. Subsurface soil information and conditions including groundwater elevations. E. Soil log information and locations of explorations. F. Soil characteristics including suitability for
fill and compaction requirements. G. Slope stability analysis. H. Seismic hazards. I. Site plan showing the topography and proposed structures and paving. J. Grading information including
depth of cuts and recommended slopes. K. Recommendations on temporary erosion and sediment control. L. Conclusions and recommendations for foundations. M. Appendix with test pit and
boring logs. N. Information on infiltration rates for use in designing retention ponds and infiltration trenches. O. California Bearing Ratio (CBR) information for pavement design. 4.03.2
Stormwater Site Plans Stormwater Site Plans shall contain the information as noted in the City of Auburn Surface Water Management Manual (SWMM) Volume I Chapter 4. The City of Auburn
SWMM has replaced the standards formerly listed here. 4.03.3 Critical Area Report A. Title Page including project name, contact information, description of the proposal, and identification
of all local, state, and other wetland related permits required for the permit. B. State accuracy of the report. C. Documentation of field work. D. Description of methodologies used
in study. E. Identify and characterize of all critical areas, wetlands, water bodies, buffers, etc. on or adjacent (within 300 feet of the project boundaries) to the proposed project
area. F. Provide wetland rating, required buffers based on a professional survey. G. A description of proposed actions including estimate acreages of impacts to wetland and buffers.
H. An assessment of probable cumulative impacts to the wetlands and buffers. I. Mitigation measures proposed. J. Scaled site plan. 2/16/2010 Design Standards Page 4-02 REF. H:\DEVELOPMENT\Manuals\Des
ign Standards\Chapter 4 (2-10)
2/16/2010 Design Standards Page 4-03 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 4 (2-10) 4.03.4 Traffic Impact Analysis A. Title Page including project name and address. B.
Executive Summary. C. Table of Contents. D. Introduction consisting of a description of the project, location, site plans with access to city streets, circulation network, land use and
zoning, phasing plan, project developer and contact person, reference other studies. E. Traffic Analysis to include assumptions, existing and projected traffic volumes, project trip
generations, trip distribution, level of service (LOS), and warrant analysis. F. Appendix with all calculations. 4.03.5 Winterization Report See Section 5.01.4 to the Engineering Design
Standards and Construction Stormwater Pollution Prevention Plan of the Surface Water Management Manual, Volume 2, Chapter 2. 4.03.6 Other Reports Other reports may be required on a site-specific
basis. The specific information required in these reports shall be determined during the SEPA process or by the department requiring the report. These reports shall include the following
basic items: A. Title page including project name and address. B. General information, which includes existing site conditions. C. Site plan showing the topography and proposed structures
and paving. D. Conclusions and recommendations. E. Appendix with collected field information.
Chapter 5 – TESC, Clearing and Grading 5.00 Preface The design of temporary erosion and sediment control (TESC) clearing and grading plans shall conform to the requirements herein. Compliance
with these standards does not alleviate the design engineer from using sound professional engineering practices. The design criteria contained herein are the minimum acceptable under
standard conditions. Special conditions may require more stringent requirements that will be addressed during the plan review process. The purpose of these requirements is to provide
the design criteria necessary to preserve the City of Auburn’s water courses; minimize surface and ground water quality degradation; control sedimentation in creeks, streams, rivers,
ponds, lakes, and other water bodies; protect adjacent and downstream property owners from increased runoff rates which could cause erosion and flooding; and ensure the safety and stability
of City of Auburn’s roads and rights-of-way. 5.01 TESC Design Criteria 5.01.1 Temporary Erosion and Sediment Control (TESC) TESC design requirements shall meet design criteria requirements
as identified in Volume II of the City of Auburn Surface Water Management Manual (SWMM), and follow City of Auburn grading requirements. All TESC measures regardless of design and implementation
must meet the latest Nephelometric Turbidity Units (NTU) test requirements. The City will conduct tests and if the applicable limits are not met, the project will be halted until such
time as it is brought into compliance. 5.01.2 Temporary Detention Systems The detention shall be defined as the active storage available a minimum of one foot (1’) above the seasonal
high ground water. 5.01.3 Winterization Plan Any project with exposed soil meeting the requirements of the SWMM Volume 2, Chapter 2 shall prepare a winterization plan. The plan shall
follow the Construction Stormwater Pollution Prevention Plan (SWPPP) of the Surface Water Management Manual, and contain the following information: A. Purpose is to be clearly stated.
B. Property location. C. Property description. D. Contacts – including name, title, organization, and phone number of person or persons responsible for maintaining the project site.
E. Temporary Erosion and Sediment Control (TESC) plan for the wet season. 2/16/2010 Design Standards Page 5-01 REF. H\DEVELOPMENT\Design Standards\Chapter 5 (2-10)
F. Inspection and monitoring schedule including the contact information for the third party monitor to be used to complete all required inspections and reports. G. Maintenance and repair
responsibility clearly identified. H. Identification of stockpile(s) of TESC materials and their location(s). I. An Exhibit A – legal description. J. An Exhibit B – vicinity map. K.
Inspection Report Form. L. BMP’s (Best Management Practices) to be employed (site specific). 5.02 Land Clearing 5.02.1 Purpose The following section establishes the requirements for
land clearing. These requirements do not supersede nor are they intended to be inconsistent with any landscaping requirement established by the Zoning Ordinance or other City action.
A land clearing permit shall be required except for the following situations: A. Situations where the land clearing is included in the grading or building permit. B. The removal of dead
or diseased trees, shrubs, or ground cover. C. Clearing associated with continuous agricultural uses, excluding timber cutting not otherwise exempted. D. Clearing not to exceed 6,999
square feet within individual lots, for the purpose of the construction of a single-family home or duplex, provided a building permit has been issued by the city prior to commencing
the clearing activities and construction of the structure starts within ninety days of commencing the clearing activities. A permit will be required if said clearing is proposed in any
critical area or within its buffer. E. The removal of up to six trees per lot within any 12-month period, or for lots greater than one acre, up to six trees per acre within any 12-month
period, with fractional acres of one-half acre or more considered to be a whole acre. F. The removal of trees and ground cover in emergency situations involving immediate danger to life
or property. G. Routine landscape maintenance and minor repair. H. Removal of trees and vegetation consistent with an approved surface mining permit. I. Removal of a tree from property
zoned residential that endangers a permanent structure by being closer to the structure than the distance from the base of the tree to its top, regardless of whether the tree is located
on the same property as the structure. Land Clearing permits will typically be required in situations where a significant amount of trees and vegetation are proposed for removal in a
manner that will not trigger the grading permit requirements. (See Section 2.01.1) 5.02.2 Plan/Permit Requirements The following information shall be provided prior to the approval of
a land clearing permit: 2/16/2010 Design Standards Page 5-02 REF. H\DEVELOPMENT\Design Standards\Chapter 5 (2-10)
A. A statement as to the purpose for clearing and the subsequent use of the property. B. The method of work including details justifying how the work will be performed without triggering
the requirements for a grading permit. C. A cover sheet and site plan (See Chapter 3) showing the vegetation to be removed and the location and type of all existing significant trees.
D. If the clearing is to include the removal of ground cover, a TESC plan may be required. E. A plan showing existing trees six inches (6”) in diameter and larger for evergreens and
four inches (4”) in diameter or larger for deciduous. The plan shall indicate if a tree is to either be retained or removed. F. The area to be cleared or disturbed in square feet. 5.02.3
General Requirements A. Clearing shall not unreasonably create or contribute to erosion, landslides, flooding, siltation, or other pollution as determined by the City. B. Clearing shall
contain reasonable provisions for the preservation of natural features, vegetation, sensitive areas, and drainage courses. C. Clearing shall be conducted so as to expose the smallest
area of soil for the least amount of time. D. A licensed and bonded contractor shall perform the clearing of any tree that is within striking distance of a structure, overhead power/utility
lines, public right-of-way, roads or that has the potential to cause damage to other trees. E. A right-of-way use permit shall be required when the public right-of-way is used to clear,
stockpile, or load products and/or debris resulting from clearing. 5.03 Grading 5.03.1 Purpose The following section establishes the requirements for grading. These requirements do not
supersede nor are they intended to be inconsistent with any landscaping requirement established by the Zoning Ordinance or other City action. A grading permit shall be required except
for the following situations: A. Removal of dead or diseased trees, shrubs, or ground cover. B. Clearing and grading associated with continuous agricultural uses, excluding timber cutting
not not otherwise exempted. C. Clearing and grading not to exceed 6,999 square feet of area within individual lots, for the purpose of the construction of a single-family home or duplex,
provided a building permit has been issued by the city prior to commencing the clearing and grading activities and construction of the structure starts within 90 days of commencing clearing
and grading activities. A permit will be required if said grading is proposed in any critical area or within its buffer. D. The removal of up to six trees per lot within any 12-month
period, or for lots greater than one acre, up to six trees per acre within any 12-month period, with fractional acres of one-half acre or more considered to be a whole acre. 2/16/2010
Design Standards Page 5-03 REF. H\DEVELOPMENT\Design Standards\Chapter 5 (2-10)
E. Clearing and grading for the construction and maintenance of public facilities as approved by the city engineer to include water, sanitary sewer, streets, highways, storm drainage
and related facilities. F. Removal of trees, shrubs, and ground cover in emergency situations involving immediate danger to life or property. G. Routine landscape maintenance and minor
repair. H. Removal of trees and vegetation consistent with an approved surface mining permit. I. Removal of a tree from property zoned residential that endangers a permanent structure
by being closer to the structure than the distance from the base of the tree to its top, regardless of whether the tree is located on the same property as the structure. J. Upon approval
of the city engineer or his/her designee, excavations of less than five feet in vertical depth and/or fills less than eight inches of vertical depth on any portion of a site and involving
the deposit or displacement of not more than a total of 500 cubic yards of material during any 24-month period. K. Upon approval of the city engineer or his/her designee, the temporary
stockpiling of less than 500 cubic yards, combined, of topsoils, crushed rock, sawdust, mulch, bark, chips, or similar materials on a lot, tract, or parcel of land for a period not ot
exceed 12 months; provided, that the stockpile has adequate coverage to prevent erosion. L. Upon approval of the city engineer or his/her designee, the broadcasting of less than 500
cubic yards of topsoil, peat, sawdust, mulch, bark, chips, or solid nutrients used for landscaping or soil conditioning on a lot, tract or parcel of land during any 24-month period,
provided the finished depth does not increase the grade from the existing grade by more than eight inches. M. Upon approval of the city engineer or his/her designee, the temporary stockpiling
of organic or inorganic materials used in an approved construction project, provided the use, location, duration, and extent of the stockpile was disclosed through the environmental
or development review process, In no case shall a temporary stockpile remain beyond a 24-month period. N. The creation of impervious surfaces which have a surface area less than 2,000
square feet. O. Emergency temporary sandbagging, diking ditching, filling or similar work during or after periods of extreme weather conditions when done to protect life or property,
provided such measures do not adversely impact adjacent properties or public facilities. 5.03.2 Excavations A. Cut slopes shall generally be constructed no steeper than two horizontal
to one vertical (2:1). The City may approve steeper slopes after a geotechnical analysis is performed justifying a steeper slope. Upon City approval, a steeper slope may also be used
in the following cases: a. A slope of one-and-a-half horizontal to one vertical (1.5:1) may be used if no structure is to be supported, the slope is less than eight feet (8’) in height,
and the slope can be adequately protected against erosion. b. A slope of one horizontal to one vertical (1:1) may be used for cuts into stable bedrock. B. Cut slopes shall be stabilized
by terracing, cat tracking, jute mat, grass sod, hydroseeding, or by other planting or surfacing materials acceptable to the City. 2/16/2010 Design Standards Page 5-04 REF. H\DEVELOPMENT\Design
Standards\Chapter 5 (2-10)
C. The City may also require geotechnical analysis for the following: a. Slopes with sub-surface or surface water flows. b. In areas of questionable soils conditions. c. Where the length
of the slope requires terracing. d. In other situations where slope stability could be in question. 5.03.3 Fills A. Fill slopes shall generally be constructed no steeper than two horizontal
to one vertical (2:1). The City may approve steeper slopes after a geotechnical analysis is performed justifying a steeper slope. Temporary fills for preloading of building pads may
use a slope one and one half horizontal to one vertical (1.5:1). B. Fill slopes shall be stabilized by terracing, cat tracking, jute mat, grass sod, hydroseeding, or by other planting
or surfacing materials acceptable to the City. C. The City may also require geotechnical analysis for the following: a. Slopes with surface water flows. b. In areas of questionable soils
conditions. c. Where the length of the slope requires terracing. d. In other situations where slope stability could be in question. D. A minimum horizontal setback of five feet (5')
shall be provided between the bottom of any fill placement and the top of the bank of any defined drainage channel. E. When filling a site, particular care should be taken to prevent
impeding the existing upstream surface drainage flow. 5.03.3.1 Preparation for Fill Prior to any fill being placed, all vegetation, topsoil and other unsuitable material shall be removed
unless dictated otherwise by the geotechnical engineer. Where fill is being placed on existing slopes of greater than five horizontal to one vertical (5:1), a geotechnical analysis shall
be performed. 5.03.3.2 Compaction Fill material shall be placed in lifts of no more than twelve inches (12”) and compacted to ninety percent (90%) or greater of the maximum dry density
as determined by ASTM D1557 Modified Proctor or as directed by the geotechnical engineer. 5.03.4 Slope Easement Slope easements adjacent to the right-of-way for maintenance of cut or
fill slopes and drainage facilities may be required. Easement shall be from the catch point plus a minimum of five feet (5’), as determined by the City. 5.04 Retaining Walls Retaining
walls can vary with design and must be approved by the City. Retaining walls in locations where the possibility exists for pedestrians to walk near the top edge of the wall may require
protective fencing. Retaining walls with a vertical difference of three feet (3’) or 2/16/2010 Design Standards Page 5-05 REF. H\DEVELOPMENT\Design Standards\Chapter 5 (2-10)
greater along pedestrian corridors and areas where maintenance personnel will be required to access will require a handrail for safety of pedestrian traffic. 5.04.1 Rockeries See Standard
Detail GENERAL-04 Rockeries may be used for containment of cut slopes or fill embankment up to a maximum height of eight feet (8’) as shown in the referenced Standard Detail GENERAL-04.
Rockeries over four feet (4’) in height or in areas of questionable soil stability will require an engineered design. The engineered design may include a soils investigation and report
by a geotechnical engineer and structural calculations to support the rockery design. 5.04.1.1 Size Size Categories include: Two-man rocks (200 -600 pounds) 18” -28” average diameter.
Three-man rocks (600 -2000 pounds) 28” -36” average diameter. Four man rocks (2001 -4000 pounds) 36” -48” average diameter. 5.04.1.2 Material The rock material shall be as rectangular
as possible. No stone shall be used that does not extend through the wall. The quarried rock shall be hard, sound, durable, and free from weathered portions, seams, cracks, and other
defects. The rock density shall be a minimum of 160 pounds per cubic foot, measured accordingly to WSDOT test method 107 (Bulk Specific Gravity -S.S.D. basis). 5.04.1.3 Underdrains Underdrains
are required for all retaining walls over four feet (4’) in height (i.e., concrete walls, MSE walls, soil nail walls, block retaining walls, etc.). A minimum six-inch (6”) diameter perforated
or slotted drainpipe shall be placed in a shallow excavated trench located along the inside edge of the keyway. The pipe shall be bedded on and surrounded by “Gravel Backfill for Drains”
(WSDOT/APWA 9-03.12(4)) to a minimum height of eighteen inches (18”) above the bottom of the pipe. A filter fabric shall surround the gravel backfill and shall have a minimum of one
foot (1’) overlap along the top surface of the gravel. The perforated pipe shall be connected to a storm drain system or to an acceptable outfall. 5.04.2 Block Retaining Walls Block
Block retaining walls, (e.g., Keystone, Allan Block, Ecology Block) may be used for containment of cut slopes or fill embankment. Block retaining walls over four feet (4’) in height
or in areas of questionable soil stability will require an engineered design. The engineered design may include a soils investigation and report by a geotechnical engineer and structural
calculations to support the block wall design. 5.04.2.1 Material Blocks used for retaining walls shall be in good condition and structurally sound; cracked and/or broken blocks should
be returned to the manufacturer. Unless designed as a gravity wall (ecology blocks), block walls over four feet (4’) in height shall employ geo-grid type material to increase the structural
stability of the wall. 5.04.2.2 Underdrains (See Section 5.04.1.3) 2/16/2010 Design Standards Page 5-06 REF. H\DEVELOPMENT\Design Standards\Chapter 5 (2-10)
5.04.3 Reinforced Concrete Walls Reinforced concrete walls or cast-in-place concrete walls may be used for containment of cut slopes or fill embankment. Concrete retaining walls over
four feet (4’) in height or in areas of questionable soil stability will require an engineered design. The engineered design may include a soils investigation and report by a geotechnical
engineer and structural calculations to support the concrete wall design. 5.04.3.1 Material A minimum 3,000-psi structural reinforced concrete shall be used in the design of concrete
retaining walls. 5.04.3.2 Underdrains (See Section 5.01.4.3) 5.04.4 Mechanically Stabilized Earth Walls (MSE Walls) MSE walls may be used in conjunction with other retaining walls or
as a stand-alone application when constructing fill slopes. MSE walls will require an engineered design. The engineered design shall include a soils investigation and report by a geotechnical
engineer and structural calculations to support the MSE wall design. 5.04.4.1 Material MSE walls shall employ well-draining structural soil compacted to the geotechnical engineer’s specifications.
5.04.4.2 Underdrains (See Section 5.01.4.3) 2/16/2010 Design Standards Page 5-07 REF. H\DEVELOPMENT\Design Standards\Chapter 5 (2-10)
5.05 Construction Sequence 5.05.1 Requirements A construction sequence is intended to ensure that the timing and installation of storm drainage and erosion control measures are in place
prior to activities that may cause erosion to occur.
The following elements should be included in a construction sequence: A. Attendance at a pre-construction meeting with City of Auburn officials. B. Establishment of clearing and grading
limits. C. Construction of temporary construction entrance. D. Construction of perimeter ditches, filter fabric fences, and other erosion control devices as shown. E. Construction of
storm drainage control (applicant to be specific) facilities including emergency overflow as applicable. F. Construction of ditches and swales as necessary to direct all surface water
to the storm drainage control (be specific) facilities as clearing and grading progress. Prevention of uncontrolled surface water being allowed to leave the site at any time during the
grading operations. G. Establishment of at what point grading activities can begin, which is usually only after all perimeter drainage and erosion control measures are in place. H. For
sites with a final development plan, the following shall also be addressed when applicable: 1. Installation of on-site permanent storm drainage, sanitary sewer, and water facilities.
2. Site paving. 3. Indicate at what point building construction may begin. 4. A description of how to transition from the temporary to permanent storm facilities. 5. The possibilities
of any phased construction. 6. Any off-site public or private improvements including the general timing and duration. 7. The removal of all TESC measures at project completion upon City
approval. I. The TESC plan sheet shall also include a construction sequence element which clearly identifies the timing and methodology required to: 1. Contain areas of active earthwork
to prevent uncontrolled discharge of storm drainage 2. Minimize erosion and the extent and time soils are exposed on-site. 3. Address seasonal variations in weather conditions (the period
of greatest concern is October 1 through April 30). A separate winterization may be required. 4. Prevent tracking of sediment onto City streets. 2/16/2010 Design Standards Page 5-08
REF. H\DEVELOPMENT\Design Standards\Chapter 5 (2-10)
2/16/2010 Design Standards Page 5-09 REF. H\DEVELOPMENT\Design Standards\Chapter 5 (2-10) 5. Protect permanent on-site and off-site storm drainage systems.
Chapter 6 -Storm Drainage 6.00 Preface The purpose of these requirements is to provide the design criteria necessary to preserve the City of Auburn’s water courses; to minimize surface
and ground water quality degradation; to control the sedimentation in creeks, streams, rivers, ponds, lakes, and other water bodies; to protect adjacent and downstream property owners
from increased runoff rates which could cause erosion and flooding; to ensure the safety of City of Auburn’s roads and rights-of-way; and to decrease drainage-related damage to both
public and private property. The standards also are required to control runoff from development, redevelopment and construction sites to comply with the Western Washington Phase II Municipal
Stormwater Permit issued by the State of Washington Department of Ecology. Compliance with these standards does not alleviate the design engineer from using sound professional engineering
practices. The design criteria contained herein are the minimum acceptable under standard conditions. Special conditions may require more stringent requirements that will be addressed
during the plan review process. The City’s Comprehensive Drainage Plan establishes drainage basins and design parameters used to estimate future line hydraulic capacities. Anyone proposing
to extend or modify the City’s storm drainage system should contact the Public Works Department for information on line sizes and locations. Developer constructed public storm drainage
improvements shall be installed by means of a Facility Extension Agreement (FAC) between the developer and the City. The Public Works Department can provide information on this agreement
as well as applicable permit and connection fee estimates. 6.01 Requirements All requests for developing a storm drainage system must comply with the City of Auburn Surface Water Management
Manual (SWMM). The City of Auburn SWMM has replaced the standards formerly listed here. 02/16/2010............................................. Design Standards ......................................
..........Page 6-1 REF. H\DEVELOPMENT\Design Standards\Chapter 6 (02-10)
Chapter 7 – Water Facilities 7.00 Preface The design of Public Water Facilities shall conform to the State of Washington Department of Health (DOH) Design Standards for Group A Public
Water Systems, Standard Specifications of the American Water Works Association (AWWA), and the most recent published and adopted edition of the Uniform Plumbing Code (UPC), unless modified
herein. Compliance with these standards does not alleviate the design engineer from using sound professional engineering practices. The design criteria contained herein are the minimum
acceptable under standard conditions. Special conditions may require more stringent requirements that will be addressed during the plan review process. The design criteria used to estimate
future line capacities are established in the City’s Comprehensive Water Plan. Anyone proposing to extend or modify the City’s water system should contact the Public Works Department
for information. Developers needing to construct water improvements shall enter into a Facility Extension Agreement (FAC) with the City. The Public Works Department can provide information
on this agreement as well as applicable permit and connection fee estimates. 7.01 Design Criteria 7.01.1 Water Mains The design of water mains shall meet the following requirements:
7.01.1.1 Water Main Sizing Public water mains shall be sized using the following criteria: A. Water mains in single-family residential areas shall be a minimum of eight inches (8”) in
diameter. B. Water mains in multi-family residential and non-residential areas shall be a minimum of twelve inches (12”) in diameter. Onsite water main loops, with no possibility of
future extension, serving two or less fire hydrants may be reduced to a minimum diameter of eight inches (8”). C. New mains shall be sized as indicated in the City's Comprehensive Water
Plan. D. Under fire flow and other emergency demand conditions, the flow velocity shall not exceed eight feet per second (8 fps) in distribution mains or five feet per second (5 fps)
in transmission mains. E. Exceptions to the minimum diameter allowed might be made in small cul-desacs and in areas where looping of a main is not feasible. In these cases the main stubs
could be a minimum of four inches (4”) in diameter if no fire hydrants are connected. If a conflict arises between two or more of these criteria, the water main should be designed using
the largest pipe diameter required. 8/9/2004 Design Standards Page 7-01 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 7 (8-04)
7.01.1.2 Water Main Location A. Water mains shall be installed with no less than forty-two inches (42”) and no more than seventy-two inches (72”) finished cover. B. Water mains shall
be located in the public right-of-way or within a public water utility easement. Water mains located in the public right-of-way shall meet the requirements of Section 9.01.2. C. Water
mains shall be located a minimum horizontal distance of ten feet (10’) from buildings and sanitary sewer mains and a minimum horizontal distance of five feet (5’) from all other utilities.
D. When crossing, water mains shall be located a minimum vertical distance of eighteen inches (18”) above sanitary sewer mains and a minimum vertical distance of twelve inches (12”)
from all other utilities. E. Water mains shall be extended through the full width of the property to be served. Whenever possible, provisions shall be made for looping all existing and
new dead-end mains associated with the project. If at the time of project approval this is not feasible, an easement shall be provided to the adjacent property line or right-of-way for
future looping of the dead-end main. 7.01.1.3 Water Main Fittings A. Blowoffs (See Standard Detail WATER-03 or WATER-04) are required on dead-end water mains with a diameter of six inches
(6”) or less; hydrants are required for dead-end mains over six inches (6”) in diameter. Blowoffs shall also be installed at the low point of a depressed “sag” section of a water main,
except where a fire hydrant is installed within fifty feet (50’) of said area. Blowoffs shall be placed in a level clear area within the right-of-way or easement and be easily accessible
to the City. B. Combination air release valves (See Standard Detail WATER-02) are required at high points in water mains when an abrupt vertical change in pipe elevation exceeds one
pipe diameter, except where fire hydrants are installed within fifty feet (50’). Combination air release valves shall be placed within a level clear area within the right-of-way or easement
and be easily accessible to the City. C. All bends shall have mechanical or flanged joints and concrete thrust blocking (See Standard Detail WATER-01). The City may require restrained
joints in lieu of thrust blocking in special conditions. D. Tees shall have mechanical or flanged joints and concrete thrust blocking (See Standard Detail WATER-01). When connecting
to an existing public water main, a tapping tee and valve shall be used unless otherwise approved or required by the City. E. The maximum allowable deflection per joint for ductile iron
water mains shall be four degrees (4°). 8/9/2004 Design Standards Page 7-02 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 7 (8-04)
7.01.2 Water Services See Standard Details WATER-06, -13 Through -17 The City owns and shall maintain the service line to the meter, the meter and setter, the meter tailpiece, and the
meter box. The property owner owns and shall maintain the tailpiece connection fitting, service line, and other facilities such as pressure reducing valves, pumps, or backflow prevention
assemblies behind the meter. For fire sprinkler connections, City ownership and maintenance responsibilities cease at the edge of the public right-of-way or public water utility easement.
7.01.2.1 Domestic Services Domestic Services are defined as any service that connects directly to plumbing within a structure and is used for drinking, cooking, washing, and other standard
uses of potable water. Domestic services shall meet the following requirements: A. Installation of corporation stops, water services, and meters shall be per City of Auburn Standard
Details. The City may, at the City's option, install services from public water mains to the the meter in existing right-of-ways and easements. The developer/contractor will install
and/or replace all applicable services when installing new water mains required for the project. The City will furnish and install the meter for services of two inches (2”) and smaller.
B. Water services and meters of three inches (3”) and larger will be purchased and installed by the developer/contractor under City observation. Where vaults are required, the meter
shall be equipped with a remote read device that records water use in cubic feet. The remote read device shall be located near the hatch opening in a weather-tight enclosure. C. Water
meters shall be located in a level unobstructed area as close to the City main as possible with the distance not to exceed fifty feet (50’). D. Residential sites should have water meters
placed in landscape strips within the right-of-way. If no unpaved areas exist in the right-of-way, water meters may be placed outside the right-of-way in unpaved areas within a public
water utility easement. E. Commercial and industrial sites should have meters located near driveway entrances within the right-of-way or within public water utility easements in landscape
islands located near access driveways when placement in right-ofway is not practical. F. Domestic water meter sizing calculations shall be per the most recent adopted Uniform Plumbing
Code and will be provided by the Developer when requested. The length of the service between the meter and the structure should not exceed one hundred fifty feet (150’). G. When installing
multiple services to a public main, a minimum spacing of two feet (2’) shall be used between corporation stops and a minimum spacing of ten feet (10’) shall be used between tapping tees.
H. Domestic services shall protect the City’s water system from contamination by installing backflow prevention assemblies required by and in accordance with Washington State Law (WAC
246.290.490 or subsequent revisions), Auburn City Code (ACC), and the City of Auburn ”Cross Connection Control Program Manual.” Prior to installation, four (4) sets of backflow prevention
assembly plans, including the connection point to the City main, shall be submitted to City for approval by the City’s Cross Connection Specialist. 8/9/2004 Design Standards Page 7-03
REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 7 (8-04)
7.01.2.2 Other Services Irrigation and other non-domestic services must meet all the above requirements as well as the following: A. Backflow prevention assemblies shall be installed
on all non-domestic services. Double Check Valve Assemblies (DCVA) shall be used for “low hazard” services and Reduced Pressure Backflow Assemblies (RPBA) shall be used for “high hazard”
services. (For lists of low and high hazard services contact the City of Auburn’s Cross Connection Specialist.) Assemblies installed shall be on the current Washington State Department
of Health (DOH) Approved List. Backflow prevention shall be installed within one hundred feet (100’) of the City water main and inspected by the City. These assemblies shall be installed
as required by and in accordance with Washington State Law (WAC 246.290.490 or subsequent revisions), Auburn City Code (ACC), and the City of Auburn ”Cross Connection Control Program
Manual.” Prior to installation, four (4) sets of backflow prevention assembly plans, including the connection point to the City main, shall be submitted to the City for approval by the
Cross Connection Specialist. B. An Irrigation meter shall be installed in cases where water is used for landscape purposes and will not enter the sanitary sewer system. C. A sewer deduct
meter, if applicable, shall be installed between the domestic water meter and the point of connection for an approved industrial use. D. For fire sprinkler service line requirements,
see Section 7.01.5.2. 7.01.3 Water Valves Water valves shall meet the following requirements: 7.01.3.1 Water Valve Sizing A. Water valves for twelve-inch (12”) diameter and smaller water
mains shall be of the resilient wedge gate variety. When water mains exceed twelve inches (12”) in diameter, butterfly valves shall be used. 7.01.3.2 Water Valve Location See Standard
Details WATER-18 Through -18b A. Water valves shall be installed along the water mains at a maximum spacing of four hundred feet (400') and at the intersection of lateral lines. B. Water
valves shall be located in clusters when possible and shall be located so that each leg of the main line system can be isolated separately. C. When extending public water mains, a water
valve may be required near the end of lines where future extensions are projected. D. Water valves should not be placed within the wheel path of vehicle traffic. E. An all-weather maintenance
road shall be provided within the public water utility easement to allow access to valves and other appurtenances located outside of the paved roadway. 8/9/2004 Design Standards Page
7-04 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 7 (8-04)
7.01.4 Pressure Reducing Stations See Standard Details WATER-10 Through -12b Pressure Reducing Station installation may be required to maintain adequate pressure in the water system
between pressure zones. Contact the City Water Utility Engineer for specific requirements when applicable. 7.01.5 Fire Systems 7.01.5.1 Fire Hydrant Assemblies See Standard Detail WATER-07
& -08 Fire Hydrant Assemblies shall meet the following requirements: A. Fire hydrant assemblies shall conform to the standard details listed above. B. Fire hydrant assembly service lines
shall be installed at right angles to eightinch (8") minimum diameter supply mains. C. Fire hydrant assemblies shall stand plumb, be set such that the lowest outlet is a minimum of twenty-one
inches (21") above finish grade, and have a clear, level area around the hydrant with a radius of no less than sixty inches (60”). D. Fire hydrant assemblies shall be located no closer
than fifty feet (50’) to the surrounding structures. E. Fire hydrant assemblies shall be provided with two 2-1/2” National Standard Thread (NST) hose ports and one 4-1/2” NST by 5” hose
port with a Storz adapter and cap. F. The pumper port shall face the street or fire access road and be readily accessible to any fire vehicle for fire fighting and pumping operations.
G. The service line from the supply main to the fire hydrant assembly shall be six inches (6") in diameter unless the line extends over fifty feet (50’) in length, in which case pipe
eight inches (8”) in diameter shall be used. H. Fire hydrant assemblies shall be installed with a maximum spacing of six hundred feet (600') along streets in single-family zones and
three hundred feet (300') in all other zones. I. Buildings, other than single-family residences, located with portions of the building more than one hundred fifty feet (150’) in vehicular
travel from a fire hydrant assembly or with building fire flow over 2500 gpm shall require on-site fire hydrant assemblies. These hydrants shall be served by a public water main that
loops around the building, or complex of buildings, and reconnects back to a distribution supply main. 7.01.5.2 Fire Sprinkler Systems Fire Sprinkler Systems shall meet the following
requirements: A. Fire sprinkler systems shall be required in commercial/industrial and multifamily buildings according to the current fire code regulations. Sprinkler systems may also
be required in single-family residences when the length of the private access road exceeds one hundred fifty feet (150’). B. Fire sprinkler supply lines for commercial buildings, unless
designed by a Fire Protection Engineer, shall be the same diameter as the supplying water main. C. Fire sprinkler supply lines shall be separated from the public water main by a valve
located at the point of connection. 8/9/2004 Design Standards Page 7-05 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 7 (8-04)
D. The design of fire sprinkler supply lines for single-family/duplex shall be in accordance with City of Auburn Standard Detail No. WATER-09. E. A backflow prevention assembly shall
be installed on all fire sprinkler lines as required by and in accordance with Washington State Law (WAC 246.290.490 or subsequent revisions), Auburn City Code (ACC), and the City of
Auburn ”Cross Connection Control Program Manual.” When the distance from the point of connection at the main to the fire sprinkler riser assembly is less than one hundred feet (100’),
the backflow prevention assembly may be part of the sprinkler riser assembly and placed within the building’s riser room. Prior to installation, four (4) sets of backflow prevention
assembly plans, including the connection point to the City main, shall be submitted to City for approval by the City’s Cross Connection Specialist. F. A Washington State Certified Level
“U” contractor shall install underground fire sprinkler supply lines in accordance with WAC 212-80-010. Prior to installation, four (4) sets of underground fire sprinkler supply line
plans shall be submitted to the City for approval by the Fire Marshal. Both a State Certified Level “U” contractor and a Fire Protection Engineer shall stamp these plans. A letter from
a state certified sprinkler system designer stating “FOR DESIGN PURPOSES ONLY” may be attached in lieu of a stamp from the Fire Protection Engineer. G. A post indicator valve (PIV) shall
be installed on the fire sprinkler supply line between the public water main and the building. PIV’s shall be located in such a manner as to be easily visible to Fire Department personnel.
A wallmounted PIV may be installed when the exterior wall of the building is of noncombustible construction. A detail containing this information shall be included with the submitted
plans. H. Fire Department Connections (FDC’s) shall be placed within fifty feet (50’) of a fire hydrant assembly or as directed by the Fire Marshal. I. Fire sprinkler supply lines will
require the installation of detector check meters. 7.01.5.3 Fire Flows New developments or redevelopment of existing sites are required to meet the minimum City fire flow requirements
listed below. The developer shall provide information to the City to define the building specific fire flow requirements. If the building specific fire flow requirements are greater
than the minimums listed below, facilities shall be designed to meet the greater requirement. The minimum fire flow requirements are as follows: 1) Single Family Residential 1,500 GPM
@2 Hours 2) Industrial/Commercial/Multi-Family 2,500 GPM @3 Hours Developers are responsible for installing all facilities necessary to serve their property, complying with development
standards, and providing the required fire flow established by the Fire Marshal. If off-site water system improvements are necessary to meet these requirements, the Developer shall be
responsible for said improvements. The change of use of existing structures or areas may also require the installation of new facilities. 8/9/2004 Design Standards Page 7-06 REF. H:\DEVELOPMENT\Manua
ls\Design Standards\Chapter 7 (8-04)
8/9/2004 Design Standards Page 7-07 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 7 (8-04) 7.01.5.4 Fire Department and Hydrant Access Fire Department and hydrant access shall
meet the following requirements: A. Access roads shall be a minimum of twenty feet (20’) wide with a minimum vertical clearance of thirteen and a half feet (13½’). B. Turns in the access
road shall be designed using a minimum inside radius of twenty-eight feet (28’) and a minimum outside radius of forty-eight feet (48’). C. Private access roads that exceed one hundred
fifty feet (150’) in length and do not return to a public road shall be provided with a turnaround with a diameter of sixty-five feet (65’). D. On sites where the primary access may
become blocked, a secondary access road that is for emergency vehicles only may be required. 7.02 Public Water Utility Easements Public Water Utility Easements are required for the placement,
operation, and maintenance of water mains upon private property. Public Water Utility Easements shall meet the following requirements: A. Public Water Utility Easements shall extend
a minimum of seven and one-half feet (7½’) to each side of the centerline of the main, water meters, and all fire hydrants. B. Public Water Utility Easements shall be provided on the
City’s standard easement form. Legal description of the easement and the property that the easement encumbers, along with a sketch showing both, shall be stamped and signed by a licensed
land surveyor and incorporated into the easement form as exhibits. The legal descriptions and sketch shall be on plain bond paper with margins acceptable to the County of recording.
C. Public Water Utility Easements shall be reviewed by the City and then recorded in the appropriate County prior to acceptance of the public water main. 7.03 Material Requirements For
Water Systems Unless otherwise approved by the City, all water mains shall be constructed using Special Class 52 Cement Lined Ductile Iron Pipe. The list of acceptable valves, fittings,
and other appurtenances for water facility construction is subject to change as new and improved components become available. Please refer to the City of Auburn’s Construction Standards
manual (latest edition) for the most current information on these requirements.
Chapter 8 – Sanitary Sewer Facilities 8.00 Preface The design of sanitary sewer facilities shall be in conformance with the applicable sections of the State of Washington Department
of Ecology’s "Criteria for Sewage Works Design" manual unless modified herein. These standards are set forth as a minimum requirement for the planning and design of gravity sanitary
sewer facilities. Sewage lift stations and special facilities are not included within this design manual due to the complexity of these facilities. When designing lift stations and special
facilities, please contact the City for the specific requirements. Compliance with these standards does not alleviate the design engineer from using sound professional engineering practices.
The design criteria contained herein are the minimum acceptable under standard conditions. Special conditions may require more stringent requirements that will be addressed during the
plan review process. The City’s Comprehensive Sanitary Sewer Plan establishes drainage basins and design parameters used to estimate future line capacities. Anyone proposing to extend
or modify the City’s sanitary sewer system should contact the Public Works Department for information on proposed line sizes and locations. Sanitary sewer improvements shall be constructed
by means of a Facility Extension Agreement (FAC) between the developer and the City. The Public Works Department can provide information on this agreement as well as applicable permit
and connection fee estimates. 8.01 Design Criteria 8.01.1 Sanitary Sewer Mains The design of sanitary sewer mains shall meet the following requirements: 8.01.1.1 Sanitary Sewer Main
Sizing Public sanitary sewer mains shall be sized using the following criteria: A. All sanitary sewer mains shall be a minimum of eight inches (8") in diameter. B. All new lines shall
be sized as indicated in the City's current Comprehensive Sanitary Sewer Plan. C. Sanitary sewer mains should be designed and constructed to provide a minimum cleaning velocity of two
feet per second (2 ft/s) when flowing at eighty percent (80%) full. If at final build out the planned contributing area will not achieve this capacity, additional provisions may be required.
D. The following are the minimum slopes recommended by the City for the corresponding pipe sizes: Pipe Size Minimum Slope 8” 0.50% 10” 0.30% 12” 0.25% 8/9/2004 Design Standards Page
8-01 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 8 (8-04)
8.01.1.2 Sanitary Sewer Main Location A. The desired installation depth for sanitary sewer mains is between eight feet (8’) and fifteen feet (15’) below the finished surface elevation.
B. Sanitary sewer mains shall be located in the public right-of-way or within a public sanitary sewer utility easement. Sanitary sewer mains located in the public right-of-way shall
meet the requirements of Section 9.01.2. C. Sanitary sewer mains shall extend through the property being served. D. Sanitary sewer mains shall be located a minimum horizontal distance
of ten feet (10’) from structures and water mains and a minimum horizontal distance of five feet (5’) from all other underground utilities. If soil conditions are poor and/or the sanitary
sewer main is deep, the horizontal distance from structures may be increased. E. At crossings, sanitary sewer mains shall be located a minimum vertical distance of eighteen inches (18”)
from water mains, preferably below the water main, and a minimum vertical distance of twelve inches (12”) from all other underground utilities. 8.01.2 Sanitary Sewer Manholes Sanitary
sewer manholes shall meet the following requirements: 8.01.2.1 Sanitary Sewer Manhole Type and Size A. Sanitary sewer manholes shall be of the “Type I” variety topped with an eccentric
cone. B. Sanitary sewer manholes over fifteen feet (15’) deep and/or greater than sixty inches (60”) in diameter may require special provisions. C. Sanitary sewer manhole diameters shall
meet the following requirements based on the manhole depth and the size, number, and configuration of pipes entering: Manhole Diameter Number & Diameter of pipes. Depth of Manhole 48”
Diameter 1 Pipe, 21” 2 Pipes, 12” – 18” 3 Pipes, 8” – 10” 4’ Minimum 12’ Maximum 54” Diameter 1 Pipe, 36” 2 Pipes, 21” – 30” 3 Pipes, 12” – 18” 4 Pipes, 8” – 10” 6’ Minimum 15’ Maximum
60” Diameter 1 Pipe, 42” 2 Pipes, 24” – 36” 3 Pipes, 15” – 21” 4 Pipes, 10” – 12” 5 Pipes, 8” 8’ Minimum 20’ Maximum 72” Diameter 1 Pipe, 48” – 54” 2 Pipes, 36” – 42” 3 Pipes, 18” –
24” 4 Pipes, 12” – 15” 5 Pipes, 8” – 10” 8’ Minimum 25’ Maximum 8/9/2004 Design Standards Page 8-02 REF. H:\DEVELOPMENT\Manuals\Design
Standards\Chapter 8 (8-04)
D. Drop manholes are discouraged. When necessary, drop manholes shall conform to Standard Detail SEWER-05 with the manhole diameter increased to offset the space occupied by the drop
pipe. 8.01.2.2 Sanitary Sewer Manhole Locations Sanitary sewer manholes shall be located using the following criteria: A. Sanitary sewer manholes shall be installed at a maximum spacing
of four hundred feet (400’). B. Sanitary sewer manholes shall be installed at all junctions of two or more sanitary sewer mains. C. Sanitary sewer manholes are required whenever connecting
to a sanitary sewer main with an eight-inch (8”) or larger diameter pipe. D. Sanitary sewer manholes shall be installed at all changes of direction, slope, and/or pipe size. E. All public
sanitary sewer lines shall end with a manhole unless otherwise approved by the City. Kor-n-Seal boots shall be supplied with one (1) length of sanitary sewer pipe stubbed out of the
manhole with a watertight cap to facilitate future sewer main extension. F. Sanitary sewer manholes are not to be located within the limits of parking lot detention facilities or in
areas of surface water ponding. G. Sanitary sewer manholes should be located outside the wheel paths of roadways. H. Sanitary sewer manholes shall not be located within sidewalks, trails,
or curb and gutter lines. I. An all-weather maintenance road shall be provided within the public sanitary sewer utility easement to allow access to manholes located outside of the paved
roadway. 8.01.2.3 Sanitary Sewer Manhole Parameters A. Sanitary sewer manholes shall provide a minimum of one-tenth of a foot (0.10’) of drop between the inlet pipe and the outlet pipe.
Pipes of various diameters shall be aligned so that the crowns of the pipes match. B. Pipes entering manholes are to be channeled to the outlet pipe, with the sidewalls of the channel
extended above the top of the pipe. The bench inside the manhole shall be sloped at a two percent (2%) grade to the channel. C. Manholes set in gravel shoulders or other non-paved, improved
areas shall be set at the center of a six-foot (6’) diameter concrete apron flush with the finished grade. D. Manholes set in non-paved and unimproved areas shall be set six inches (6”)
to twelve inches (12”) higher than the surrounding terrain and provided with a six-foot (6’) diameter concrete apron around the manhole lid. E. Sanitary sewer manholes shall be equipped
with a solid locking lid with the words “Confined Space Permit Required” cast into the lid. 8/9/2004 Design Standards Page 8-03 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 8
(8-04)
8.01.3 Side Sewers See Standard Detail SEWER -01 Side sewers are defined as that portion of the sewer system that extends from two feet (2’) outside of the outer foundation wall of the
structure to the sanitary sewer main. The City owns and maintains the side sewer from the sanitary sewer main to the edge of the right-of-way or public sanitary sewer utility easement.
The property owner owns and maintains the side sewer from that point to the building. Side sewers shall meet the following requirements: 8.01.3.1 Side Sewer Parameters A. A separate
and independent side sewer from the public main shall be provided for each and every building. B. Side sewers within the public right-of-way shall be a minimum of six inches (6”) in
diameter. C. Six-inch (6”) diameter side sewers shall be connected to sanitary sewer pipe by the use of a tee. D. Side sewers with a diameter of eight inches (8”) or greater shall be
connected to the sanitary sewer system by use of a sanitary sewer manhole. E. When constructing sanitary sewer mains in new developments, side sewer installation shall extend from the
connection on the main line to the edge of any utility easements or the public right-of-way whichever is further. F. When installing new sanitary sewer mains or replacing existing mains
in developed areas, side sewers shall be installed for all existing occupied structures and any buildable lots. Side sewers should be extended to the property lines and out of the public
right of way whenever possible. G. The maximum length of side sewer from the sanitary sewer main to the building should not exceed one hundred and fifty feet (150’). H. Side sewers shall
be designed to provide a minimum depth at the property line of five feet (5’) below the floor to be served or six feet (6’) below the street, whichever is deeper. In cases of vacant
properties, the side sewer shall be constructed at a two percent (2%) slope from the tee. I. Cleanouts shall be installed within three feet (3’) of the building foundation and at the
property line marking the location of the side sewer and providing an access point into said line for future maintenance. 8.01.4 Sanitary Sewer Cleanouts See Standard Detail SEWER-02
& -03 Sanitary sewer cleanouts shall meet the following guidelines and are not an acceptable alternative for sanitary sewer manholes: A. Sanitary sewer cleanouts may be used with City
approval at the end of a sanitary sewer main when the future extension of the sanitary sewer main is planned and the current end point is not a practical location for a manhole. B. A
sanitary sewer cleanout may be used in lieu of a manhole at the end of a long private side sewer. C. Sanitary sewer cleanouts shall be installed in side sewers for each change in direction
exceeding ninety degrees (90°). 8/9/2004 Design Standards Page 8-04 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 8 (8-04)
8.01.5 Fats, Oils, and Grease (FOG) and Sand/Grit Interceptors Fats, Oils, Grease and Sand Interceptors shall be designed using the Uniform Plumbing Code and meet the following requirements:
A. FOG interceptors shall be provided on all newly constructed or remodeled restaurants, cafés, lunch counters, cafeterias, bars or clubs; hotel, hospital, factory or school kitchens;
or other establishments that serve or prepare food where FOG may be introduced to the sanitary sewer system. They shall be provided for the proper handling of liquid wastes containing
petroleum-based (non-polar) or animal and vegetable (polar) oil and grease in excess of that identified in ACC 13.20.140(B) or any flammable wastes, sand, or other harmful ingredients.
The City shall approve the location of these devices. B. Private property owners should perform grease trap maintenance on a regular basis. Grease interceptor (GI) maintenance shall
be performed by permitted haulers or recyclers and consists of removing the entire volume (liquids & solids) from the GI and properly disposing of the material in accordance with all
Federal, State, and/or local laws. When performed properly and at the appropriate frequency, grease interceptor and trap maintenance can greatly reduce the discharge of animal/vegetable
fats, oils, or grease (FOG) into the wastewater collection system. C. A FOG Control Plan shall be submitted to the City for review prior to the issuance of a side sewer permit for any
establishment where FOG may be introduced into the sanitary sewer system. At a minimum, the following items shall be addressed in a FOG Control Plan: 1. A written policy articulating
management and corporate support for the plan and a commitment to implement planned activities and achieve established goals. 2. A description of the facility type and a summary of the
products made and/or service provided. 3. Quantities of FOG brought into the facility as raw product, amounts contained in products, and quantities discharged to the sewer. 4. Schematics
of process areas illustrating drains and discharge points connected to the sewer. 5. A description of current reduction, recycling, and treatment activities. 6. Identification of a full
range of potentially feasible reduction opportunities. 7. Specific performance goals and implementation schedule including cleaning frequency. 8. Signature of owner. D. Sand and Grit
Interceptors will be required if it is determined that excessive amounts of grit are being discharged into the sanitary sewer system. A control plan meeting the same requirements as
noted above shall be submitted with the installation of sand and grit interceptors. E. Once the interceptor is installed, the City will require copies of all maintenance and cleaning
reports within ten (10) days of service. These records shall be kept onsite for two (2) years. The required maintenance frequency for grease interceptors and traps depends greatly on
the amount of fats, oils, and grease discharged to the sanitary sewer system. Certification of maintenance shall be made readily available to Cityauthorized personnel for review and
inspection. Certification of maintenance records shall be submitted to the City and be kept on-site for two (2) years. 8/9/2004 Design Standards Page 8-05 REF. H:\DEVELOPMENT\Manuals\Design
Standards\Chapter 8 (8-04)
Establishments that implement the best management procedures should realize financial benefit through a reduction in maintenance frequency. 8.01.6 Sanitary Sewer Pumps The installation
of public and private pumping facilities are discouraged within the City’s sanitary sewer system. All proposed pumping facilities require the City Engineer’s approval. Please contact
the City for a handout containing the latest requirements. 8.02 Public Sanitary Sewer Utility Easements Public Sanitary Sewer Utility Easements are required for the placement, operation,
and maintenance of public sanitary sewers within private property. Public Sanitary Sewer Utility Easements shall meet the following requirements: A. Public Sanitary Sewer Utility Easements
shall extend a minimum of seven and onehalf feet (7½’) to each side of the centerline of the sanitary sewer main. Easements shall extend ten feet (10’) to either side when the sanitary
sewer main is over ten feet (10’) deep or soil conditions are unstable. B. Public Sanitary Sewer Utility Easements shall be provided on the City’s standard easement form. Legal description
of the easement and the property that the easement encumbers, along with a sketch showing both, shall be stamped and signed by a licensed land surveyor and incorporated into the easement
form as exhibits. The legal descriptions and sketch shall be on plain bond paper with margins acceptable to the County of recording. C. Public Sanitary Sewer Utility Easements shall
be reviewed by the City and then recorded in the appropriate County prior to acceptance of the public sanitary sewer facilities. 8.03 Material Requirements for Sanitary Sewer Systems
The following list of sanitary sewer materials is for reference only. The list of acceptable materials and appurtenances for sanitary sewer construction is subject to change as new and
improved components become available. Please refer to the City of Auburn’s Construction Standards manual (latest edition) for the most current information on these requirements. 8.03.1
Sanitary Sewer Pipes Pipe Type Minimum Depth Maximum Depth Solid Wall Polyvinyl Chloride (PVC) Pipe, SDR-21 18 inches 22 feet Solid Wall Polyvinyl Chloride (PVC) Pipe, SDR-35 (Requires
13.5’ lengths. 3 feet 18 feet Solid Wall Polyvinyl Chloride (PVC) Pipe, C900 12 inches 30 feet* Sewer Safe Ductile Iron Pipe (Protecto 401 Ceramic Epoxy Lined) 6 inches 30 feet* * Sanitary
sewers below thirty feet (30’) will require pre-approval of the City. 8/9/2004 Design Standards Page 8-06 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 8 (8-04)
8/9/2004 Design Standards Page 8-07 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 8 (8-04) 8.03.2 Sanitary Sewer Structures Structure Type Depth Extra Shallow MH (City Std. Detail
SEWER-06) 31” Minimum 48” Maximum Type I with eccentric cone (WSDOT Std. Plan B-23a) 4’ Minimum 20’ Maximum Type II (WSDOT Std. Plan B-23b) 20’ Minimum 30’ Maximum See also Section 8.01.2.1.
Chapter 9 – Utilities 9.00 Preface The design of public and private utilities located within City right-of-way shall be in conformance with these standards. Compliance with these standards
does not alleviate the design engineer from using sound professional engineering practices and meeting the requirements of the specific utility in question. The design criteria contained
herein are the minimum acceptable under standard conditions. Special conditions may require more stringent requirements that will be addressed during the plan review process. 9.01 Design
Criteria The City has established the following minimum requirements to ensure the efficient construction of utilities with the least impact to City transportation and utility infrastructure.
9.01.1 Private Utilities Located Within City Right-of-Way Unless otherwise provided in a public way agreement, franchise, or lease, a grantee, franchisee, or lessee with permission to
occupy a public way must locate its cable or telecommunications facilities underground. 9.01.1.1 Private Utilities Located Underground Private utilities located underground shall meet
the following requirements: A. Private utilities shall be installed with no less than thirty-six inches (36”) of finished cover. B. Private utility lines to be located within the City
right-of-way will require prior approval from the City. These utility companies shall have a current franchise or public way agreement consistent with Title 20 of the Auburn City Code.
C. Private utilities shall be located a minimum horizontal distance of five feet (5’) from buildings and public utilities. D. When crossing public utilities, private utilities shall
be located a minimum vertical distance of twelve inches (12”) from the public utility. 9.01.1.2 Private Utilities Located Aboveground On projects where underground requirements do not
apply, the following parameters will need to be addressed in locating aboveground utilities: A. Utility poles and other aboveground utility structures located on roads with a curb shall
be installed a minimum of two feet (2’) from the face of curb with the preferred location being at the edge of the right-of-way. For urban and rural roads where no curb is present, utility
poles and other aboveground utility structures shall be located outside the clear zone in accordance with the AASHTO manual “A Policy on Geometric Design of Highways and Streets.” B.
Utility poles and other aboveground utility structures should not be located within the sidewalk. If this is not possible, their locations shall provide a minimum of forty-eight inches
(48”) of travelway to meet ADA requirements. 8/9/2004 Design Standards Page 9-01 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 9 (8-04)
C. Utility poles and other aboveground utility structures shall be compatible with driveways, intersections, and all other road features. They shall not interfere with sight distance,
road signing, traffic signals, culverts, etc. This may require that existing poles be relocated at the developer’s expense. D. No utility pole or other aboveground utility structures
shall be located in such a way as to pose a hazard to the general public. Utility companies shall locate and replace poles and other structures with primary consideration given to public
safety and roadway functionality. When a developer-driven project requires the relocation of private utilities due to public utility extensions or other City required improvements, the
cost of relocation of the private utility shall be borne by the developer. 9.01.2 Public and Private Utilities Located Underground Within City Right-of-Way Any developer, utility, or
other entity intending to trench in the existing City street shall contact the City of Auburn Public Public Works Department and obtain a construction permit. A City permit must be obtained
prior to any work within the City right-of-way. Manholes, valve boxes, power vaults, etc., that are located in the paved area of a street shall be located outside of the wheel paths
of vehicles and flush with the pavement surface. Structures located within parking lots, sidewalks, and paths/trails shall also be flush with the surface. In areas where traffic will
pass over the structure, load-bearing lids shall be incorporated in the design. All trenches within paved areas shall have their edges sawcut and meet the following requirements: 9.01.2.1
Perpendicular Trenching in Asphalt Pavement A. Perpendicular trenching shall be in accordance to Standard Detail TRAFFIC-02 or as directed by the City. B. Pavement restoration shall
match existing pavement type and thickness unless otherwise directed by the City. C. In the process of perpendicular trenching, if the remaining section of pavement between the trench
and the edge of the pavement/gutter is less than four feet (4’), the patch will extend from the trench to the edge of the road pavement. D. Perpendicular trenching to roadways may not
be allowed on newer roads or streets that have been constructed or overlaid within the last five (5) years. E. Perpendicular trenching may not be allowed or may be limited to off-peak
hours and/or weekends on principal arterials or where the construction activity will seriously impede large volume traffic patterns. Utility connections that have to be made within the
roadway will be allowed after approval from the City. F. Jacking/boring alternatives may be required as substitute methods for perpendicular trenching. G. The minimum pavement patch
width for perpendicular trenches shall be six feet (6’). This width may be reduced upon City approval for narrow, shallow utility trenches. H. When multiple trenches are required in
close proximity, the asphalt patch shall encompass all the trenches. 8/9/2004 Design Standards Page 9-02 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 9 (8-04)
8/9/2004 Design Standards Page 9-03 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 9 (8-04) I. The longitudinal edge of the perpendicular asphalt patch shall not lie within the
wheel paths of vehicles. 9.01.2.2 Longitudinal Trenching in Asphalt Pavement A. Longitudinal trenching shall be in accordance with Standard Detail TRAFFIC-03. B. Pavement restoration
shall match existing pavement type and thickness unless otherwise directed by the City. C. In the process of longitudinal trenching, if the remaining section of pavement between the
trench and the edge of the pavement/gutter is less than four feet (4’), the patch will extend from the trench to the edge of the road. D. Longitudinal trenches shall be backfilled and
paved to within one-inch (1”) of the existing pavement surface. The driving lane within which the trench is located shall be ground to a depth of one and one-half inches (1½”) and repaved
with asphalt concrete pavement. If the trench crosses lanes or encompasses more than one lane, the pavement shall be ground to a minimum width of eleven and one-half feet (11½’) with
the trench being the centerline. E. The longitudinal edges of the asphalt patch shall not lie within the wheel paths of vehicles. F. For newer roads, streets that have been constructed
or overlaid within the last five (5) years, principal arterials, or where open trenching will seriously impede large volume traffic patterns, the City may require that trenching be limited
to off peak hours and/or weekends or may require that jacking/boring be researched as an alternative. 9.01.2.3 Trenching in Concrete Pavement Trenching in concrete pavements shall conform,
where applicable, to the previous sections and the following: A. The edges of trenches in concrete pavement shall be sawcut prior to excavation to avoid damaging the slab. Concrete slabs
six inches (6”) and over shall be drilled for the installation of dowels. Dowels shall be one and one-quarter inches (1¼”) in diameter, eighteen inches (18”) long, and spaced twelve-inch
(12”) 12”) center to center. B. The minimum pavement patch width for concrete trenches shall be four feet (4’). C. In the process of trenching concrete, if the section of pavement between
the trench and the edge of the existing concrete panel is less than four feet (4’), the section will need to be removed and replaced. D. Longitudinal trenches in concrete may be repaved
with an asphalt pavement thickness of equivalent strength upon City approval. 9.01.2.4 Trenching in Other Right-of-Way Surfaces Trenching in other right-of-way surfaces, including sidewalks,
gravel shoulders, and landscape strips, shall conform, where applicable, to the previous sections and replace the disturbed material in kind or as directed by the City.
Chapter 10 – Streets 10.00 Preface The intent of this chapter is to encourage the uniform development of an integrated and accessible public street system that will support present and
future multimodal transportation. Through the implementation of these standards, streets are built as transportation facilities as well as public space, contributing positively to the
character of an area. These standards help create an efficient multimodal transportation system with minimal environmental impact to the community. The design of Streets within the City
of Auburn shall conform to the standards provided herein. The latest additions of the American Association of State Highway and Transportation Officials (AASHTO) and the State of Washington
Department of Transportation (WSDOT) standards shall be utilized by the City Engineer when the design standards, standard specifications, or standard drawings are not covered by the
scope of the City’s standards. The design criteria used to estimate future street usage are established in the City’s Transportation Plan. Anyone proposing to extend or modify the City’s
street system should contact the City of Auburn for information. Developers needing to construct street improvements shall enter into a Facility Extension Agreement (FAC). The City of
Auburn can provide the information on this agreement as well as applicable permit fee estimates. It is provided, however, that notwithstanding any provisions to the contrary, all streets
located within the Downtown Urban Center Zone boundaries as depicted on the Comprehensive Zoning Map, other than that area west of the BNSF Railroad right-of-way, shall be subject to
the “Downtown Auburn Sidewalk Design Guidelines” (Guidelines). Should any conflict exist between the Guidelines and the design criteria, Chapter 10, of this document, the Guidelines
shall control in those portions of the Downtown Urban Center Zone described above. 10.01 Street Classification All streets in the City of Auburn have been classified using the Federal
Functional Classification system. A complete listing of all roads by classification is available from the Department of Public Works. The following section contains descriptions of the
street classifications used in the City. Table 10-1 contains information relating to each streets design requirements for widths, radii, typical speed limits, and other information.
This section also contains references to Standard Details that show a typical cross-section for each street. These cross-sections contain information on street layouts and widths of
various street elements. 10.01.1 Arterials Arterials are the highest level of City Street classification. They fall under the following two categories: 12/21/2009 ....................................
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10.01.1.1 Principal Arterial See Standard Detail TRAFFIC-27 Principal Arterials are designed to move traffic between locations within the region and to access the freeways. Design emphasis
should be placed on providing movement of inter-city through-traffic rather than intra-city traffic. Direct access to commercial and industrial land uses is permitted. Principal Arterials
are typically constructed to accommodate five (5) lanes of traffic with an operating speed of thirty-five to forty-five miles per hour (35-45 mph). The design year ADT is greater than
15,000 vehicles per day. 10.01.1.2 Minor Arterial See Standard Detail TRAFFIC-28 Minor Arterials should interconnect with and augment principal arterials and provide service to trips
of moderate length at a somewhat lower level of travel mobility than principal arterials. The minor arterial street system includes all arterials not classified as a principal or collector
and consists of facilities that place more emphasis on land access than the higher system system and offers a lower level of traffic mobility. Minor Arterials are typically constructed
to accommodate four to five (4-5) lanes of traffic with an operating speed of thirty to thirty-five miles per hour (30-35 mph). They may serve secondary traffic generators such as community
business centers, athletic fields, neighborhood shopping centers, major parks, multifamily residential areas, medical centers, large church complexes, hospitals, and traffic from neighborhood
to neighborhood within the City. The design year ADT is 10,000 to 20,000 vehicles per day. 10.01.2 Collectors Collectors are a step below Arterials in the City classification system.
They fall under the following three categories: 10.01.2.1 Residential Collector See Standard Detail TRAFFIC-29 Residential Collector Arterials are used to connect intra-community streets,
residential neighborhoods, commercial areas, industrial areas, and community centers to minor and principal arterials. Residential Collectors are typically constructed to accommodate
two (2) travel lanes and a two-way left-turn lane or two (2) travel lanes and bike lanes with an operating speed of thirty miles per hour (30 mph). The design year ADT is 2,500 to 10,000
vehicles per day. 10.01.2.2 Non-Residential Collector See Standard Detail TRAFFIC-30 Non-Residential Connector Arterials provide intra-community access connecting nonresidential properties
with activity centers and recreational facilities. Non-Residential Collector arterials are typically constructed to accommodate two (2) lanes and a center two-way left-turn lane, with
an operating speed of thirty miles per hour (30 mph). They may serve neighborhood traffic generators such as one store or a small group of stores, elementary schools, churches, clubhouses,
small hospitals or clinics, areas of small multifamily developments, as well as other commercial/industrial parcels. The design year ADT is 2,500 to 5,000 vehicles per day. 12/21/2009
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10.01.2.3 Rural Collector See Standard Detail TRAFFIC-31 Rural Collectors are routes that (regardless of traffic volume) the majority of travel distances are shorter than on arterial
routes and residential neighborhoods to activity centers. Rural Collectors provide access to all levels of arterials, are typically constructed to accommodate two (2) lanes with gravel
shoulders on both sides, and provide an operating speed of thirty to forty miles per hour (30-40 mph). The gravel shoulder may be reduced on one side to provide a wider shoulder on the
other for equestrian access, with permission from the City Engineer. The design year ADT is 1,000 to 5,000 vehicles per day. 10.01.3 Local Streets Local Streets are the most common streets
classified in the City. This classification can be broken up into four categories as follows: 10.01.3.1 Local Residential See Standard Detail TRAFFIC-32 Local Residential streets provide
access to abutting residential parcels. They offer the lowest level of mobility among all street classifications. The street is designed to conduct traffic between dwelling units and
higher order streets. As the lowest order street in the hierarchy, the access street usually carries no through traffic and includes short streets, cul-de-sacs, and courts. Service to
through traffic movement is discouraged and the street usually contains no transit bus routes. Local Residential streets are typically constructed to accommodate two (2) lanes of traffic,
on-street parking (one side only, the other side shall be signed “No Parking”), and an operating speed of twenty-five miles per hour (25 mph). The design ADT is 200 to 1,200 vehicles
per day. 10.01.3.2 Local Non-Residential See Standard Detail TRAFFIC-33 Local Non-Residential streets provide direct access to higher order classification streets and serve primarily
industrial/manufacturing land uses. They offer lower level of mobility and accommodate heavy vehicle traffic. Service to through movement is discouraged. Local Non-Residential streets
are typically constructed to accommodate two (2) lanes of traffic with an operating speed of twenty-five miles per hours (25 mph). The design year
ADT is 400 to 1,200 vehicles per day. 10.01.3.3 Rural Residential See Standard Detail TRAFFIC-34 The Rural Residential streets primarily provide access to the adjacent land and distribute
traffic to and from the principal or minor arterials and local access streets. The travel distance is relatively shorter as compared to Rural Collectors. Rural Residential streets are
typically constructed to accommodate two (2) lanes of traffic with gravel shoulders on both sides and an operating speed of twenty-five miles per hour (25 mph). The design year ADT is
100 to 1,000 vehicles per day. 10.01.3.4 Private Street Community street requirements are usually best served by public streets, owned and maintained by the City. Private streets may
be appropriate for some local accesses in very limited usage. Private streets shall provide a direct access to City streets and 12/21/2009 ............................................
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shall be limited to those streets accessing properties within a planned area or properties immediately adjacent. Private streets shall not be used by residents to travel from one public
street to another. The design of a private street shall be such that it will discourage any through traffic of non-residents. A private street will not be allowed if it will result in
land locking present of planned parcels. Private streets shall be in conformance with the street standards that most closely reflects their intended use, with a minimum of thirty-four
feet (34’) of pavement width or twenty-eight feet (28’) of pavement width with a marked fire lane on one side. Private street networks shall be configured to deter speeding. Traffic
calming measures may also be required to deter speeding. Private streets shall be located within permanently established tracts or easements. A capable, legally responsible owner or
homeowners’ association shall be established to maintain private streets. A plat or short plat with private streets requires an executed recorded Private Street Maintenance Agreement
and a Storm Water Easement and Maintenance Agreement that obligate the future property owners to maintain the infrastructure indefinitely. 10.01.4 Alleys Alleys afford a secondary means
of vehicular access to abutting property and are not intended for general traffic circulation. Dead-end alleys are generally unacceptable; however, where dead-end alleys are determined
suitable by the City Engineer, for short term or temporary applications, they shall be provided with adequate turnaround facilities at the dead-end. All new alleys shall be private.
Alleys shall incorporate the design criteria used in designing local streets with the following exceptions: A. All new alleys shall have a minimum width of twenty feet (20’) of asphalt
pavement. B. Developments that generate four (4) or greater PM peak hour trips and have direct access to existing alleys are required to pave the alley to a width of twenty feet (20’)
along the frontage of the property and between the nearest property line and the public street that provides the City preferred travel path. If adequate right-of-way does not exist to
provide the required twenty feet (20’) of pavement adjacent to the property, the appropriate dedication of right-ofway shall be required. Such dedication shall be equally apportioned
from both sides of the alley, when feasible, as determined by the City Engineer. If adequate right-of-way does not exist to provide the required twenty feet (20’) of pavement along the
alley between the nearest property line and public street, the alley shall be paved to the width of the existing right-of-way. C. The pavement section for alleys located in non-single
family zones shall be consistent with a local non-residential street standard. D. Curb and gutter, sidewalk, lighting, and landscaping are not required along alleys. E. Alleys may be
paved with either a crown at centerline with asphalt wedge curbs on both sides to control drainage or be sloped to one side with an asphalt wedge curb on one side to control drainage.
When necessary, storm drainage conveyance systems shall be installed along the alley to address storm drainage runoff from the paved surface. F. Alleys shall connect to City streets
via a commercial driveway apron. 12/21/2009 ............................................ Design Standards.............................................. Page 10-4 REF. H\DEVELOPMENT\Design
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Alleys serving alley loaded lots shall include provisions for unimpeded vehicular circulation along the alley, and provisions for adequate sight distances along both the alley at driveways
and at intersections with public streets. 10.01.5 Private Access Roads on Access Tracts or Easements (Shared Driveways) Access roads provided on access tracts or easements, also known
as shared driveways, provide access for up to four (4) residential units in short plats and up to six (6) residential units in long plats on panhandle/flag lots and rear lots that do
not have direct access to public street frontage. They will be private roads that shall be maintained by the property owners who use them to access their property. All access roads shall
meet the following general standards: 1. Access roads shall be limited to six hundred feet (600’) in length. 2. The width of the access tract/easement shall match the required pavement
width, including the width of any pedestrian improvements, and the area needed for private drainage facilities. If the access is also acting as a joint utility easement or tract, the
width must accommodate the public utility requirements. 3. The connection of an access road to the public street shall be by a commercial driveway apron. The connection of individual
lots to the access road shall be by either a residential or commercial driveway apron commensurate with the use of the property. 4. Access roads shall meet the geometric design standards
for local residential streets. 5. Access roads shall be signed as private drives inclusive of all addresses being served off the access road. New and/or existing access roads serving
two (2) residential units shall meet the following additional standards: 6. The minimum pavement width shall be twenty-four feet (24’). The pavement width may be reduces to twenty feet
(20’) if the new residential unit using the access road has a residential fire sprinkler system installed or a fire hydrant exists within four hundred and fifty feet (450’) of the residences
measured as the fire vehicle lays its hose. Existing access roads serving three (3) or more residential units when only one additional residential unit is being created or developed
shall meet the following additional standards: 7. The minimum pavement width shall be twenty-four feet (24’) and be marked as a fire lane per ACC 15.36A. The pavement width may be reduced
to twenty feet (20’) if the new residential unit using the access road has a residential fire sprinkler system installed or a fire hydrant exists within four hundred and fifty feet (450’)
of the residences measured as the fire vehicle lays its hose. 8. An additional five foot (5’) wide pedestrian pathway along one side of the paved access road separated by a four-inch
(4”) wide painted line. 9. Access roads exceeding one hundred and fifty feet (150’) in length shall also include an adequate turnaround at the end of the road. 12/21/2009 ............................
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New access roads serving three (3) to six (6) residential units shall meet the following additional standards: 10. Access roads seventy-five feet (75’) or less in length shall have a
minimum pavement width of twenty feet (20’) and shall be marked as a fire lane per ACC 15.36A. 11. Access roads exceeding seventy-five feet (75’) in length shall have a minimum pavement
width of thirty-four feet (34’). The pavement width may be reduced to twenty-four feet (24’) if one side of the access road is marked as a fire lane per ACC 15.36A. 12. Access roads
exceeding one hundred and fifty feet (150’) in length shall also include an adequate turnaround at the end of the road. 13. An additional five foot (5’) wide sidewalk and cement concrete
traffic curb per F-10.12-00 is required on both sides of the access road. The material for the sidewalk shall be consistent with the surrounding neighborhood sidewalk. New access roads
serving non-residential properties shall meet the following additional standards: 14. The minimum pavement width shall be twenty-four feet (24’) for access roads servicing commercial
properties and thirty feet (30’) for access roads serving industrial properties. 15. The access road will be marking as a fire lane per ACC 15.36A. 16. Access roads exceeding one hundred
and fifty feet (150’) in length shall also include an adequate turnaround at the end of the road. 10.01.6 Half-Streets A Half-Street could be comprised of any one of the above mentioned
street classifications. Half-Streets require, at a minimum, the construction from one side of the street, including the curb and gutter, storm drainage, sidewalk, lighting, conduits,
and landscape strip, to the street centerline. Half-Streets will need to be constructed when a proposed new development or redevelopment of a property is located on a public street that
is not currently built to City standards. Half-Street construction may also be required for property that abuts future streets proposed in the City’s Comprehensive Plan. When Half-Street
construction is required on an existing paved street, the design of the Half-Street shall be consistent with the existing street conditions. This could require construction of more than
half the street for safety and drainage reasons. When Half-Street construction is required on unpaved streets or unimproved areas, a minimum of twenty-four feet (24’) of pavement will
be required. In these cases, the street should be designed to provide drainage for the constructed portion of the street. Provisions shall be made to allow for extension of the storm
drainage system to the undeveloped portion of the street for future construction. The construction of a Half-Street may require the dedication of additional right-of-way. If a Half-Street
does not connect at both ends to other streets, construction of a cul-de-sac will be required. Where Half-Streets are connected to existing streets, transition tapers will be required
when edges of pavement do not match. The following formula provides the information necessary to determine the length of the tapers for a specific situation: For street design speeds
of less than forty miles per hour (40mph) 12/21/2009 ............................................ Design Standards.............................................. Page 10-6 REF. H\DEVELOPMENT\Design
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W = the width of the pavement offset = L S = the design speed in mph L = the length of the taper For street design speeds of greater than or equal to forty miles per hour (40 mph) W
= the width of the pavement offset WS = L S = the design speed in mph L = the length of the taper All required utilities located within the portion of the street being built, shall be
installed during construction. Half-Street construction may also require the upgrading of existing utilities if said upgrading was necessary for the proposed development. The unfinished
side of the Half-Street shall be finished with temporary curbing, shoulders, clear zones, guardrail, slope treatments, and drainage accommodations to assure proper drainage, bank stability,
and traffic safety. When Half-Streets connect to an intersection, the nearest corner of the intersection on the side being improved shall be designed and constructed for the full build-out
of the street. The intersection design and construction shall include adequate improvements improvements to insure safe use by pedestrians, bicycles, and vehicles. WS2 60 12/21/2009
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10.02 Street Geometry For in-depth design information on the following criteria, please reference the AASHTO Manual “A Policy on Geometric Design of Highways & Streets,” latest adopted
edition. 10.02.1 Minimum Horizontal Curve Radius Horizontal curves shall be designed to provide the minimum radii required for vehicles to safely negotiate a turn without leaving their
driving lane and shall in no case violate minimum sight distance requirements. Minimum radii are established by the design speed of the street on which the curve is located and are listed
in Table 10-1. On arterials and rural collectors these radii may be reduced by superelevating the road cross-section. 10.02.2 Tangents Between Reverse Curves Sections of straight roadway
must be designed between curves to avoid quick left-right transitions that could potentially lead to loss of vehicular control. The length of these straight sections should be a minimum
of one hundred fifty feet (150’) for arterials and collectors and one hundred feet (100’) for local residential streets. Where reversing curves are superelevated, tangents between curves
shall be of sufficient length to accommodate transitions into and out of the superelevated sections. 10.02.3 Superelevations The process of superelevating a street provides a constant
cross slope from one edge of the roadway to the other. This allows vehicles to travel around a turn at a higher speed than would be possible if the road were a normal crown cross section.
Superelevations are allowed only on arterials and rural collectors. The maximum superelevation rate allowed for these streets is eight percent (8%) and requires a design speed of thirty-five
miles per hour (35 mph) or greater. 10.02.4 Vertical Grades Vertical Grades, the amount of slope of a street in the direction of travel, is limited to a maximum of six percent (6%) for
Arterials and eight percent (8%) for all other streets. All street sections shall maintain a minimum of one-half percent (0.5%) vertical grade. Vertical grades may be increased up up
to ten percent (10%) for non-arterials upon approval of the City Engineer. The City Engineer shall consider the public benefit of any deviation request including the classification of
the roadway, traffic circulations, traffic congestion, emergency access, adjacent property access, length of grade, impact to public utilities, or any operational or safety factors.
Deviations to the vertical street grade of a classified roadway shall generally not be granted unless it can be demonstrated that the public benefits significantly outweigh any potential
detriments. If approved, grades between eight percent (8%) and ten percent (10%) may trigger the additional following design considerations: • Increased travel lane widths • Enhanced
Paving Section • Incorporation of Separated Multi-use trail • Incorporation of Median Islands • Enhanced Intersection/Signal Improvements 12/21/2009 ............................................
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10.02.5 Vertical Curves Vertical curves are required where a change in vertical alignment equals or exceeds a one percent (1%) algebraic grade difference. Crest vertical curves shall
be designed to provide the required minimum stopping sight distance for the streets design speed as listed in Table 10-2 of Section 10-03. Sag vertical curve lengths shall be designed
to provide headlight sight distance equal to or greater than the design speed stopping sight distance. All vertical curves must be symmetrical, parabolic, and meet AASHTO standards.
The following formula provides the information necessary to calculate minimum lengths for sag vertical curves. A = algebraic grade difference, %; L = ⎟⎠⎞ ⎜⎝⎛ + − A 2S 400 3.5S S = stopping
sight distance, ft; L = length of sag vertical curve, ft 10.02.6 Cross Slopes City streets shall be crowned in the middle to provide drainage to the gutter line or roadside ditches.
The cross slopes created by this crown shall be two percent (2%) for local streets and three percent (3%) for collectors, arterials, and roads with vertical grades of greater than six
percent (6%). Collectors and arterials shall have steeper cross slopes since the higher speeds associated with these roads require that water drain more quickly from the roadway to avoid
hydroplaning. 10.02.7 Posted and Design Speed For design purposes, the “Posted Speed” for any given street segment shall be as designated in Table 10-1 or the existing signed speed limit,
whichever is greater. For design purposes, the “Design Speed” for any given street segment shall be ten miles per hour (10 mph) greater than the Posted Speed for arterials and five miles
per hour (5 mph) greater than Posted Speed for non-arterials as designated in Table 10-1. 10.02.8 Right of Way The required right-of-way will depend upon the width of the street and
other improvements. Excluding cul-de-sacs, the typical requirement is for the right-of-way to extend a minimum of ten feet (10’) behind the curb line on each side of the street. Additional
right-of-of-way may be required for bike/pedestrian trails and/or storm facilities, for example. Right-of-way requirements may be variable within a street corridor due to intersections,
turn lanes, bus loading zones, and other street features. Right-of-way shall be conveyed to the City on a recorded plat or by a right-of-way dedication or separate instrument. The minimum
right-of-way requirements for the various street classifications are listed in Table 10-1. 10.02.9 Roadway Width (Travel Way) The roadway width or travel way consists of inside through
lanes and/or curb lanes, center turn lanes and/or bike lanes (where required), and curb and gutter. Special cases may also require acceleration and deceleration lanes and right and left
turn pockets. Total roadway width is measured from the face of curb to the face of curb. 12/21/2009 ............................................ Design Standards......................................
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10.02.9.1 Inside Through Lanes and Curb Lanes The street classification and the amount of existing and projected traffic will determine the number of lanes required for a street. Curb
lanes or outside lanes on all streets excluding residential collectors and local and rural residential streets shall be a minimum of fourteen feet (14’) wide. Streets will be widened
to include inside through lanes based on street classifications and/or projected traffic volumes. The minimum width for inside through lanes shall be eleven feet (11’). 10.02.9.2 Center
Turn Lanes Center turn lanes will be required on principal and minor arterials. They may also be required on collectors depending upon the nature of the roadway and the number of left
turn movement opportunities along the corridor. Center turn lanes shall be a minimum of eleven feet (11’) wide. 10.02.9.3 Other Lanes Acceleration and deceleration lanes may be required
for sites located on arterials where heavy volumes and/or heavy truck movements into and out of the the site would impact the speed and safety of the arterial. Left turn and right turn
pockets may be required at intersections with large numbers of left and/or right turns. Left turn pockets shall be a minimum of eleven feet (11’) wide with right turn pockets a minimum
of fourteen feet (14’) wide. 10.02.9.4 Road Edge All urban roads within the City of Auburn shall be designed using concrete curb and gutter (WSDOT Plan F-10.12-00, Traffic Curb & Gutter).
Rural roads within the City may be designed with a gravel shoulder (minimum of 2⅝” Crushed Surfacing Top Coarse (CSTC) over eight inches (8”) of “gravel base”; eight feet (8’) wide for
rural collectors and three feet (3’) wide for rural residential) and a ditch for drainage. Rural roads shall also meet AASHTO standards for a clear zone between the edge of pavement
and any obstructions. 10.02.9.5 On-Street Parking On-Street parking requirements shall be as designated in Table 10-1. For Local Residential streets where parking is allowed on one side
only, the City shall require the parking to be placed on the side of the street that can accommodate the most parking. Parking is not allowed at any of the following locations: 1. Within
20 feet of an uncontrolled intersection measured from the point of tangency on the entering curb radius. 2. Within 30 feet of a stop, yield or signal controlled intersection measured
from the point of tangency on the entering curb radius. 3. Within any intersection. For “T” intersections, the no parking limits shall apply to both sides of the through street (top
of the “T”). See Figure 10-0. 4. In front of or within 15 feet of each side of a fire hydrant. 5. In front of or within 5 feet of each side of a driveway. 6. Where mid-block crosswalks
are installed, no parking shall be allowed on either side of the street within 50 feet in advance of the nearest edge of the crosswalk 12/21/2009 ............................................
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and within 20 feet past the furthest edge of the crosswalk. In no case shall the advance parking restriction for crosswalks be less than the minimum stopping sight distance of the roadway.
Additional parking restriction may be required depending upon roadway geometrics, adjacent land use, and the proximity to bridges and railroads. 10.02.9.6 Intersection Curb Radii The
minimum right-of-way requirements for the various curb radii shall be as designated in Table 10-1. At intersections with two different street classifications, the highest classification
for curb radii shall be used except at intersections with residential streets where the lowest order street. 10.02.10 Street Layout An efficient transportation system seeks to spread
vehicle movements over a series of planned streets. The goal of the system is to encourage connectivity while preventing unacceptably high traffic volumes on any one street. Ample alternatives
should exist to accommodate access for emergency vehicles. For these reasons the City will continue to plan a series of arterials and collectors designed to national standards to provide
efficient service to the community. Ample alternatives should also exist to accommodate non-motorized transportation on arterials, collectors and local roads within and between subdivisions.
10.02.10.1 Local Residential Streets The internal local residential street network for a subdivision should be designed to discourage regional through traffic and non-residential traffic
from penetrating the subdivision or adjacent subdivisions. Local residential streets shall not exceed one thousand three hundred feet (1,300’) in length between intersections and shall
not serve more than 75 dwelling units. Residential subdivisions should be planned in a manner that minimizes the number of local street accesses to arterials and collectors. Residential
subdivisions with greater than 75 lots shall have a minimum of two accesses to either an arterial or collector. Residential subdivisions developments with less than 75 lots shall have
at least one access to an arterial or collector. Residential subdivisions with between 25 and 75 lots shall also provide a second emergency vehicle access route to an arterial or collector.
10.02.10.2 Other Streets New streets and/or new street systems, other than local residential streets serving residential subdivisions, shall be configured in conformance with the City’s
comprehensive plan guidelines and policies. Where the comprehensive plan lacks clear guidance to address a particular situation, the City may require traffic studies and other supporting
analysis to help define the configuration and nature of the planned street system. 10.02.10.3 Cul-de-sacs Where possible, streets shall be planned, designed and constructed to connect
to future developments. All dead-end streets shall end in either a temporary or permanent cul-de-sac. Permanent dead-end streets or cul-de-sacs will only be allowed where a through street
to connect adjacent properties and/or other streets is not needed or possible. Dead-end streets shall not be more than six hundred feet (600’) in length as measured from the center of
the nearest intersection, unless the city determines that due to topography or existing development patterns there are no 12/21/2009 ............................................ Design
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feasible alternatives and emergency services can be effectively provided. Dead end streets ending in permanent cul-de-sacs shall serve a maximum of 25 dwelling units. When applicable,
non-motorized paths shall be provided at the end of the street to shorten walking distances to an adjacent arterial or public facilities including, but not limited to, schools or parks.
Existing stub-end streets that are greater than eight hundred feet (800’) in length shall be linked to other streets whenever the opportunity arises, unless it can be demonstrated that
such connections would lead to a substantial rerouting of through traffic onto the street. Dead-end streets longer than eight hundred feet (800’) as measured from the center of the nearest
intersection shall not be allowed to serve substantial new development. 10.02.10.3.1 Temporary Cul-de-sacs Temporary cul-de-sacs may be provided only when there is a plan for extending
the street. Temporary cul-de-sacs shall have a paved surface with a diameter of sixty-five feet (65’). A sign shall be posted at the back of the temporary cul-de-sac stating that the
road is planned to be extended in the future and to contact the City of Auburn Public Works Department for further information. 10.02.10.3.2 Permanent Cul-de-sacs Permanent cul-de-sacs
shall have a paved surface with a diameter of seventy-five feet (75’) unless otherwise directed by the City. Permanent cul-de-sacs right-of-way shall have diameter of ninety feet (90’)
unless otherwise directed by the City. 10.02.10.4 Traffic Volumes Projected trip generation shall be calculated based on the current edition of the Institute of Transportation Engineers
(ITE) Trip Generation Manual. Stub end streets shall not be linked to a new street if the connection is likely to result in traffic volumes that will exceed acceptable volumes for the
road’s classification. These volumes are defined in Table 10-1 of these standards. Consideration may also be given to the character and nature of the neighborhoods proposed to be connected.
10.02.11 Figure 10-0 -T-Intersection Parking Restrictions 12/21/2009 ............................................ Design Standards............................................ Page 10-12
REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.03 Sight Distance Sight distance is defined as the length of roadway ahead that is visible to the driver. All roads, intersections, and access pointes should be designed to provide
sight distance of sufficient length that drivers can control the operation of their vehicles to avoid striking an unexpected object in the traveled way. 10.03.1 Sight Distance Design
The requirements for stopping sight distance and intersection sight distance listed in this section were taken from AASHTO’s “A Policy on Geometric Design of Highways and Streets” manual
as a quick reference guide and are for passenger cars on level roadways. Deviations from City design standards may require additional sight distance study and documentation. Sight distance
design calculations will also be required for design grades not listed in the tables below. 10.03.1.1 Stopping Sight Distance Stopping sight distance is the distance required at every
point along a roadway for a vehicle traveling at or near the road’s design speed to come to a stop before reaching a stationary object in its path. Table 10-2 contains the minimum design
values that shall be used for stopping sight distance. In calculating stopping sight distance, the driver’s eye is assumed to be three and a half feet (3.5’) above the roadway and the
height of the object to be seen by the driver is assumed to be two
feet (2’) above the roadway. 10.03.1.2 Intersection Sight Distance Intersection sight distance is the clear sight distance necessary for a driver entering a controlled or uncontrolled
intersection to proceed safely without impeding traffic. Table 10-2A contains the minimum design values that shall be used for intersection sight distance. The City Engineer may require
the use of single unit of combination trucks as the design vehicle for minor road approaches with five percent (5%) or greater heavy vehicle volumes. 10.03.1.2.1 Major Road and Minor
Road For the purposes of intersection sight distance analysis, the Minor Road shall be defined by any of the following criteria: 1. The controlled approaches of a Two-Way Stop Controlled
Intersection. 2. The roadway with lower classification, lower design speed of lower traffic volumes. 3. For uncontrolled intersections of similar classification, design speed and volume
roadways, the City Engineer shall designate the minor roadway. 4. Minor Roads include driveways, alleys, access tracts or any other location accessing a public road. 10.03.1.2.2 Sight
Triangles Intersection, driveway, and access point sight distances are analyzed using the applicable sight triangles per Figures 10-1 and 10-2. These sight triangles shall be provided
on site plans including landscaping and other potential sight obstructions for all projects where intersections, driveways or access points are being installed 12/21/2009 ............................
................ Design Standards............................................ Page 10-13 REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
or modified. Additionally, the City Engineer may require supporting documentation for vertical sight distance profile analysis on street grades over three percent (3%). 10.03.1.2.2.1
Measurements Horizontal: Horizontal legs of the sight distance triangles on the major road are measured along the roadway centerline. Major road vertex points are placed at the midpoint
of the traveled lane closest to the approach being analyzed. Minor road vertex points are placed in accordance with following applicable sections for uncontrolled and controlled intersections.
Vertical: In calculating vertical sight distance at intersections the driver’s eye is assumed to be three and a half feet (3.5’) above the roadway surface and the object to be seen is
three and a half feet (3.5’) above the surface of the intersecting road. 10.03.1.2.2.2 Restrictions The area within the sight distance triangle must be free from any sightobscuring objects
from between three feet (3’) and eight feet (8’) above the ground. Sight-obscuring objects include but are not limited to: buildings, parked vehicles, signs, fences, and landscaping.
10.03.1.2.2.3 Right-of-Way Requirements The sight distance triangle shall be located completely within the City right-ofway. The City will require a right-of-way dedication as a condition
of development approval to ensure the sight distance triangle is contained completely within the City right-of-way. If the City Engineer determines that this is not practical a “Sight
Distance Easement” shall be required. 10.03.1.2.3 Uncontrolled Intersections For uncontrolled intersections (intersections without signals, stop signs or yield signs) the sight distance
triangle dimensions are determined by applying the applicable distances listed in Table 10-2A to the respective legs of the sight distance triangle as shown on Figure 10-1. 10.03.1.2.4
Two Way Stop Controlled Intersections In calculating intersection sight distance for Two Way Stop Controlled intersections the vertex (decision point) of the sight triangle on the minor
road shall be measured fourteen and a half feet (14.5’) back from the nearest edge of the traveled roadway. Where parking is allowed on the major road this distance shall be measured
from the far edge of the parking lane. Left turns from the minor road: Using Figure 10-2 sight triangles for traffic approaching from both the left and right should be provided using
the value in Table 10-2A that corresponds to the major road design speed. Right turns from the minor road: Using Figure 10.2 a sight distance triangle for traffic approaching from the
left should be provided using the value in Table 10-2A that corresponds to the major street design speed. 10.03.1.2.5 All Way Stop Controlled Intersections At All Way Stop Controlled
intersections, the first stopped vehicle on one approach should be visible to the drivers of the first stopped vehicles on each of the other approaches. 12/21/2009 ...................................
......... Design Standards............................................ Page 10-14 REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.03.1.2.6 Signalized Intersections At signalized intersections the first stopped vehicle on one approach should be visible to the drivers of the first stopped vehicles on each of the
other approaches. Left-turning vehicles should have sufficient sight distance to complete left turns. Additionally, if right turns on a red signal are permitted from any approach then
the appropriate sight triangle should be provided to accommodate right turns on that approach. 10.03.1.3 Decision Sight Distance Decision sight distance is used in cases where the driver
is required to detect unexpected or confusing situations and then make appropriate changes in their driving style or method. This could mean changing lanes, slowing down, or coming to
a complete stop. Decision sight distance will need to be addressed when designing roads with tight turns and unexpected driveway and street connections. When decision sight distance
requirements are applicable, the guidelines presented in the latest edition of AASHTO shall be used. used. 10.03.1.4 Passing Sight Distance Passing sight distance should be addressed
when designing two (2) lane roads where vehicle speeds can differ by a considerable amount depending on the driver. When passing sight distance requirements are applicable, the guidelines
presented in the latest edition of AASHTO shall be used. 12/21/2009 ............................................ Design Standards............................................ Page 10-15
REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.03.2 Table 10-2 Stopping Sight Distance Stopping Sight Distance (ft) Downgrades* (Equation 10-2) Upgrades* (Equation 10-2) Design Speed (MPH) Level Roads (Equatio n 10-1) 3% 6% 8%
10 % 3% 6% 8% 10% 15 80 80 82 84 86 75 74 73 72 20 115 116 120 124 128 109 107 105 104 25 155 158 165 170 176 147 143 141 139 30 200 205 215 223 232 200 184 181 178 35 250 257 271 282
294 237 229 225 220 40 305 315 333 347 363 289 278 272 267 45 360 378 400 418 438 344 331 324 317 50 425 446 474 495 520 405 388 379 370 55 495 520 553 579 609 469 450 438 428 60 570
598 638 669 705 538 515 501 489 Equation 10-1: (Grades < 3%) a d Vt V 2 = 1.47 +1.075 Equation 10-2 (Grades ≥ 3%) ⎟ ⎟⎠ ⎞ ⎜ ⎜⎝ ⎛ ± ⎟⎠⎞ ⎜⎝⎛ = + a G d Vt V32.2 30 1.47 2 d = stopping sight
distance, ft. V = design speed, mph a = deceleration rate of 11.2ft/s2 t = brake reaction time, 2.5s G = percent grade divided by 100 Data for this table was taken from the 5th edition
of AASHTO’s “A Policy on Geometric Design of Highways and Streets” manual, Exhibit 3-1 Stopping Sight Sight Distance and Exhibit 3-2 Stopping Sight Distance on Grades. *Use Equation
10-2 above to calculate appropriate stopping sight distances for grades not shown. 12/21/2009 ............................................ Design Standards............................................
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10.03.3 Table 10-2A Intersection Sight Distance Intersection Sight Distance, (ft) Uncontrolled Intersections* Use Figure 10-1 Two Way Stop Controlled Intersections** Use Figure 10-2
(Equation 10-3) Design Speed (mph) Dimensions “a” and “b” Dimension “a” for Left Turns (Table10-2C) Dimension “a” for Right Turns (Table 10-2D) 15 70 170 145 20 90 225 195 25 115 280
240 30 140 335 290 35 165 390 335 40 195 445 385 45 220 500 430 50 245 555 480 55 285 610 530 60 325 665 575 Equation 10-3: major g ISD = 1.47V t ISD = intersection sight distance (length
of the leg of sight distance triangle along the major road) (ft) major V = design speed of major road (mph) g t = time gap for minor road vehicle to enter the major road(s) Data for
this table was taken from the 5th edition of AASHTO’s “A Policy on Geometric Design of Highways and Streets” manual’s Exhibit 9-51 Length of Sight Triangle Leg-No Intersection Control,
Exhibit 9-55 Design Intersection Sight Distance-Left Turn from Stop, and Exhibit 9-58 Design Intersection Sight Distance-Right Turn from Stop and Crossing Maneuver. * Where grade along
an uncontrolled intersection approach exceeds 3%, the leg of the clear sight triangle along that approach should be adjusted by multiplying the sight distance listed in this table by
the appropriate adjustment factor in Table 10-2B. ** Intersection sight distance shown is for a stopped passenger car to turn onto a two-lane road with no median and grades of three
percent (3%) or less. For other conditions, the time gap ( ) will need to be adjusted per Tables 10-2C /10-2D and the sight distance recalculated. g t *** Refer to the latest edition
of the AASHTO manual for sight distance requirements on major street left turns and at yield controlled intersections. 12/21/2009 ............................................ Design
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10.03.4 Table 10-2B Uncontrolled Intersection Sight Distance Adjustment Factors Adjustment Factors Approach Design Speed (mph) Grade (%) 15 20 25 30 35 40 45 50 55 60 -10 1.1 1.1 1.2
1.2 1.2 1.2 1.2 1.2 1.2 1.2 -8 1.1 1.1 1.1 1.1 1.1 1.2 1.2 1.2 1.2 1.2 -6 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.2 1.2 1.2 -5 1.0 1.0 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 -4 1.0 1.0 1.0 1.1 1.1 1.1
1.1 1.1 1.1 1.1 -3 to 3 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 4 1.0 1.0 1.0 1.0 1.0 0.9 0.9 0.9 0.9 0.9 5 1.0 1.0 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 6 1.0 1.0 0.9 0.9 0.9 0.9 0.9 0.9
0.9 0.9 8 1.0 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 10 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 0.9 Note: Apply adjustment factor to sight distance measurement for each approach. Data for this
table was taken from AASHTO Exhibit 9-53. 10.03.5 Table 10-2C Time Gap for Left Turns Design Vehicle Time gap( g ) (seconds) at design speed of major road t Passenger Car 7.5 Single
Unit Truck 9.5 Combination Truck 11.5 Note: Time gaps are for a stopped vehicle to turn left onto a two-lane roadway with no median and grades 3 percent or less. Table 10-2A values require
adjustments as follows: For Multilane roads: For left turns onto two-way highways with more than two lanes add 0.5 seconds for passenger cars and 0.7 seconds for trucks for each additional
lane, from the left, in excess of one, to be crossed by the turning vehicle. For minor road approach grades: If the approach grade is an upgrade that exceed 3 percent; add 0.2 seconds
for each percent grade for left turns 12/21/2009 ............................................ Design Standards............................................ Page 10-18 REF. H\DEVELOPMENT\Design
Standards\Chapter 10 (01-10)
10.03.6 Table 10-2D Time Gap for Right Turns Design Vehicle Time gap( ) (seconds) at design speed of major road g t Passenger Car 6.5 Single Unit Truck 8.5 Combination Truck 10.5 Note:
Time gaps are for a stopped vehicle to turn right onto or cross a two-lane roadway with no median and grades 3 percent or less. Table 10-2A values require adjustments as follows: For
Multilane roads: For crossing a major road with more than two lanes add 0.5 seconds for passenger cars and 0.7 seconds for trucks for each additional lane to be crossed and for narrow
medians that cannot store the design vehicle. For minor road approach grades: If the approach grade is an upgrade that exceed 3 percent; add 0.1 seconds for each percent grade for left
turns 12/21/2009 ............................................ Design Standards............................................ Page 10-19 REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.03.7 Figure 10-1 Intersection Sight Triangles for Uncontrolled Intersections 12/21/2009 ............................................ Design Standards............................................
Page 10-20 REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.03.8 Figure 10-2 Intersection Sight Triangles for Two-Way Stop Controlled Intersections 12/21/2009 ............................................ Design Standards....................................
........ Page 10-21 REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.04 Street Access Points All access points to and from City streets, including intersections and driveways, shall be approved by the City prior to construction. These access points
shall meet all the requirements contained throughout this chapter for sight distance, spacing, and other safety considerations. The following section contains design criteria on all
access points including street intersections and driveways. These criteria are minimum values and may need to be modified according to safety factors, traffic volumes (existing and/or
projected), topography, design speed, design vehicle requirements, drainage, and other conditions, both existing and projected. 10.04.1 Public Street Intersections Public Street Intersections
are intersections where two (2) or more City streets intersect. These intersections shall be designed using the following criteria: 10.04.1.1 Intersection Spacing Public street intersections
shall meet the minimum centerline spacing requirements as shown in Table 10-3. 10.04.1.2 Horizontal Approach Angle The horizontal approach angle of public street intersections shall
be between 85° and 95° at the centerlines of intersecting streets. 10.04.1.3 Intersection Approach Offsets Public Street intersections shall be aligned so that opposing single left turn
lanes and through lanes are not offset more than four feet (4’) as measured from the lane centerline approach tangent. 10.04.1.4 Curb and Right-of-Way Radius A minimum curb radius is
required at intersection corners for vehicles to safely execute a right turn at a reasonable rate of speed without crossing lanes or encroaching onto the adjacent curb. At intersections
of differing street classification, the higher classification street curb radius requirements shall be used. The exception to this rule is for local residential streets where the minimum
radii listed in Table 10-1 shall be used. The right-of-way radius is the additional radius required to install sidewalks, landscape strips, and other roadway appurtenances. Additional
right-right-ofway may be required near intersections to accommodate auxiliary traffic lanes and equipment for existing or future traffic signals and street lights. These minimum values
and listed in Table 10-1. 10.04.1.5 Landing Approach The landing approach is a defined segment of the street before the intersection and is measured back from the point of tangency of
the curb radius on each approach to the intersection. The requirements for minimum landing approach length and maximum landing approach grade are listed in Table 10-1. 12/21/2009 ....................
........................ Design Standards.........................................Page 10-22 REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.04.1.6 Street Crowns Public street intersections shall be designed to drain away from the higher classification street. Grades shall match at the center of intersections for equal
classification streets. At intersections of differing classification streets the crown shall be carried through the intersection for the higher classification. 10.04.2 Private Street
Intersections Private street intersections are those intersections where a private street intersects a City street. These intersections shall be designed in the same manner as public
street intersections, except that the private streets will be stop-controlled. 10.04.3 Table 10-3 Minimum Intersection Spacing from Centerline to Centerline (ft) PRINCIPAL ARTERIAL MINOR
ARTERIAL RESIDENTIAL & NONRESIDENTIAL COLLECTORS RURAL COLLECTOR LOCAL STREETS 5001 5001 250 250 125 LOCAL STREETS 1320 1320 500 500 250 RURAL COLLECTOR 2640 1320 500 500 250 RESIDENTIAL
& NONRESIDENTIAL COLLECTORS 2640 2640 1320 1320 5001 MINOR ARTERIAL 2640 2640 2640 1320 5001 PRINCIPAL ARTERIAL Notes: 1. Local streets shall generally not be allowed to access directly
onto arterials. 2. Refer to section 10.03 for intersection sight distance requirements. 3. Refer to section 10.05 for intersection pedestrian accessibility requirements. 12/21/2009 ..................
.......................... Design Standards.........................................Page 10-23 REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.04.4 Driveways See Standard Detail TRAFFIC-07 through TRAFFIC-11 Driveways can be broken into the following classifications: A. Residential Driveways – Driveways to single family
residences. B. Commercial/Industrial Driveways – Driveways to all properties except single family residential. C. Temporary Driveways – Driveways to property allowed prior to and during
construction only. D. Emergency Driveways – Driveways required by the fire department to provide an alternative emergency-only access to the property. E. Signalized Driveways – For special
circumstances when no other option is available, the City may allow signalized access to a public street from a private access. In such situations, dedication to the City of any right-of-way
necessary for maintaining and operating the intersection will be required. Additional mitigation measures may be required to ensure safe and efficient access to the public street. The
private leg of the intersection within the right-of-way shall be designed to the applicable public street standard as determined by the City. 10.04.4.1 Driveway Locations Most properties
shall be limited to one driveway access to a City street (or alley). Multiple driveway accesses to a street (or alley) shall only be allowed when the City determines that the second
access does not create a safety concern or impede traffic flow. To address safety or to mitigate impacts of traffic flow, the City may require two or more contiguous non-single family
properties to share a single driveway, and/or require the driveway to be located on the lowest classification of street (or alley) when a property has frontage on two or more streets
(or alleys). Driveway accesses within the “Functional Intersection Boundary” shall be either prohibited or restricted in conformance with Section 10.04.4.1.1 below. The City may also
impose driveway restrictions at other locations when a safety hazard is identified or to mitigate impacts of traffic flow along a classified street. Such restrictions shall be incorporated
into the design of the driveway in conformance with the provisions of Section 10.04.4.5 in a manner that strives to maintain existing access turning movements to other properties in
the vicinity. Redeveloped properties are not guaranteed that their existing driveways will be retained. Redeveloped properties that meet the requirements for half street improvements,
have more than one access point, or do not meet current City standards may be required to eliminate, relocate or modify existing driveway access/accesses. Except for Local Residential
Streets the spacing of driveways and their separation from intersections shall meet the minimum “Functional Intersection Boundary” distances of this Chapter. 12/21/2009 ..............................
.............. Design Standards.........................................Page 10-24 REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.04.4.1.1 Function Intersection Boundary See Table 10-4 and Figure 10-3 The functional intersection boundary is the portion of the street leading up to the intersection required to
allow vehicle movements and storage. This is the area within which drivers identify the situation, change lanes, come to a stop, and wait before proceeding through the intersection.
Driveways shall be either prohibited or restricted within the functional intersection boundary in accordance with Table 10-4 and Figure 10-3.The functional length of an intersection
is measured from the point of curvature/point of tangency (PC/PT) of the curb return. Driveway restrictions include prohibiting either all left turn movements, left turns out of, or
left turns into the subject driveway. 10.04.4.1.2 Table 10-4 *Distance Requirements for Functional Intersection Boundaries Speed mph Speed ft/sec Reaction Time (sec) Decision Distance
(ft) ”d1” Lane Change Distance (ft) ”d2” Braking Distance (ft) ”d3” Storage Length (ft) ”d4” Functional Intersection Boundary Length d1+d2+d3+d4 (ft) 25 mph 37 1 37 25 60 50 222 30 mph
44 1 44 40 86 50 270 35 mph 51 1 51 60 118 100 329 40 mph 59 1 59 85 154 100 398 45 mph 66 1 66 105 194 100 465 50 mph 73 1 73 140 240 100 553 10.04.4.1.3 Figure 10-3 Functional Length
Diagram of an Intersection with Right and/or Left-Turn Lane 12/21/2009 ............................................ Design Standards.........................................Page 10-25
REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.04.4.1.4 Figure 10-4 Functional Intersection Boundary Restricted Access Diagram 12/21/2009 ............................................ Design Standards.........................................Pag
e 10-26 REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.04.4.2 Driveway Lay Out See Standard Detail TRAFFIC-11 Driveways shall be designed in such a manner as to allow for efficient and safe ingress and egress from the City streets. Driveways
and on-site parking, other than that for single-family residences on unclassified roads or alleys, shall be designed such that vehicle-backing maneuvers will not occur onto the street.
A properly designed driveway shall allow the largest typical vehicle that will use the driveway (i.e. tractor-trailers at large warehouses, delivery trucks at mini marts) to enter and
exit the site without encroaching into opposing traffic. Driveways for adjacent properties should be separated by a minimum of ten feet (10’) for residential and fifty feet (50’) for
commercial/industrial. This distance should be measured from the outside edge of the driveway apron. When this separation is not obtainable, a single driveway centered on the property
line may be required. When designing site layout and driveway access, internal circulation shall shall be such that on-site traffic will not backup the driveway impeding vehicles in
the public street. The City may require sites with internal traffic congestion to design driveways with long throat lengths to provide extra storage to avoid impacting City streets.
10.04.4.3 Driveway Alignment (Horizontal and Vertical) The angle of driveway throats to the City streets shall not be less than eighty-five degrees (85°) unless a “pork chop” or other
access control device is allowed to be utilized per Section 10.15. The vertical grade behind the driveway shall not exceed five percent (5%) for a distance of 12 feet (12’) beyond back
of sidewalk or right of way line. Driveways shall be designed to preclude vehicles from dragging when entering or exiting the site. Driveways shall meet all sight distance requirements
per Section 10.03. 10.04.4.4 Driveway Widths 10.04.4.4.1 Residential See Standard Detail TRAFFIC-07 & 08 Residential driveways shall be used when serving four (4) or fewer living units.
Driveway widths widths shall be a minimum of ten feet (10’) and a maximum of twenty-four feet (24’). Residential driveways shall be constructed using a minimum thickness of six inches
(6”) of non-reinforced concrete. 10.04.4.4.2 Commercial/Industrial See Standard Detail TRAFFIC-09 & 10 Commercial and industrial driveway widths shall be based on the number of lanes
used on the driveway and the type of use. Commercial driveways shall be constructed using a minimum thickness of eight inches (8”) of reinforced concrete The three categories described
below will be determined based on the vehicles expected to use the site. A. Light commercial/industrial driveways should be used for sites where the average vehicle use will range from
passenger vehicles to small size delivery trucks. Examples include mini marts, strip malls, fastfood restraints, triplexes, and small apartment buildings. Driveways will have one entering
lane and up to two exiting lanes with the lane widths restricted to a maximum of twelve feet (12’). 12/21/2009 ............................................ Design Standards...........................
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B. Medium commercial/industrial driveways should be used for sites where the average vehicle use will range from medium to high volumes of passenger vehicles to multiple medium delivery
trucks per day and the occasional large tractor/trailer delivery truck. Examples included supermarkets, large outlet stores, shopping malls, large apartment buildings, and busy retail
stores located on arterials. Driveways will have one entering lane and up to two exiting lanes with the lane widths restricted to a maximum of fourteen feet (14’). C. Heavy commercial/industrial
driveways should be used for sites where high volumes of medium to large tractor/trailer trucks enter and exit every day. Examples include manufacturing and storage warehouses. Driveways
will have one entering lane and one exiting lane with the lane widths restricted to a maximum of sixteen feet (16’). Driveway uses discussed above may be subject to change based on the
street classification on which they are located. For example: a site use that may normally fall under the light commercial/industrial classification may be upgraded to a medium commercial/industrial
classification if it is located on a principal or minor arterial to facilitate moving vehicles off the right-of-way in a more efficient manor. 10.04.4.5 Restricted Access Driveways Restricted
Access Driveways are used to restrict turning movements out of or into driveways. Turning restrictions at driveway locations shall be by one of the following methods as deemed appropriate
by the City. A. Median Islands (Per Section 10.15.1) B. Traffic (“C”) Curbs (Per Section 10.15.2) C. Pork Chops (Per Section 10.15.3) D. Signing (Per Section 10.15.4) E. Pavement Markings
(Per Section 10.15.5) 12/21/2009 ............................................ Design Standards.........................................Page 10-28 REF. H\DEVELOPMENT\Design Standards\Chapter
10 (01-10)
10.05 Sidewalks Sidewalk requirements vary by street classification and corridor/area specific standards as determined by the City. Sidewalks are required along both sides of all street
classifications except for rural streets. 10.05.1 Sidewalk Widths See Standard Details TRAFFIC-23 & 24 Sidewalks shall be a minimum of five feet (5’) in width for all local residential
and residential collector streets. Sidewalks shall be a minimum of ten feet (10’) in width for all principal arterials, minor arterials, non-residential collectors, and local non-residential
streets. Non-standard widths of sidewalk greater than the standards identified above may be required to maintain continuity on existing corridors. All sidewalks shall have a minimum
of five feet (5ft) of unobstructed width. 10.05.1.1 Downtown Auburn Sidewalk widths in the Downtown Urban Center Zone shall be a minimum of ten feet (10’) in width as measured from face
of curb to face of building or Right-of-way. All sidewalks in the downtown zone shall maintain a minimum walking zone of five feet (5’) in width, free of all obstructions including utilities,
signage, street trees, furniture or other elements, permanent or temporary. 10.05.2 Structural Section See Standard Details TRAFFIC-23 & 24 Sidewalks shall be a minimum of four inches
(4”) thick concrete over two inches (2”) of Crushed Surface Top Course (CSTC). At driveway crossings the sidewalk section shall match that required for the driveway. When sidewalks are
installed at the back of the curb, a thickened edge shall be provided as shown in City of Auburn Standard Details TRAFFIC 23 & 24. 10.05.3 Meandering Sidewalks The City Engineer may
approve meandering sidewalks along a corridor when the sidewalk, landscaping, lighting, signing, right-of-way, and other surface features are integrated into the design of the improvements.
Additional right-of-way
(or an easement) may be required to accommodate the meander of the sidewalk and other surface features. 10.05.4 Accessibility All sidewalks shall be designed according to the Americans
with Disabilities Act (ADA) guidelines. Cross slopes shall not exceed two percent (2%). Sidewalk grade shall not exceed the grade of the adjacent street centerline. 10.05.4.1 Curb Ramps
See Standard Details TRAFFIC-25 & 26 Curb ramps shall be provided at all intersections and pedestrian crossings having vertical curb sections. Every curb ramp shall have at least one
receiving ramp. In special conditions, curb ramps shall also be provided to enable passage across curbed radius return access points. All curb ramps shall have detectable warning patterns
formed with manufactured truncated domes painted yellow. 12/21/2009 ............................................ Design Standards.........................................Page 10-29 REF.
H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.06 Bikeways The City of Auburn bikeway standards are designed to ensure that bikeways are constructed in a manner that provides a safe and convenient network of interconnected routes
for bicycling. Bikeways are any road, street path or way which in some manner is specifically designated for the exclusive use of bicycles or are to be shared with other transportation
modes. Bikeway facilities shall be incorporated into development and transportation projects in accordance with the Future Trail and Bicycle Network plan adopted by the City of Auburn
Comprehensive Transportation Plan. Bikeways shall be designed in accordance with AASHTO’s “Guide for the Development of Bicycle Facilities 1999,” the latest adopted edition of FHWA’s
Manual on Uniform Traffic Control Devices (MUTCD), this section, and applicable City of Auburn standard details. 10.06.1 Bikeway Classifications The City of Auburn’s Future Trail and
Bicycle Network consists of various classification bikeways. Typically, these bikeways are shared with other transportation modes, although they may be provided exclusively for bicycle
use. Bikeways are categorized as follows: 10.06.1.1 Class I Bikeway Class I Bikeways are facilities shared with other non-motorized modes and are physically separated from motorized
vehicle roadways. For the purposes of this section, Class I Bikeway design standards are for bicycle facilities that generally parallel a roadway with minimal crossflow by motor vehicles.
It is designed and built primarily for use by bicycles, but may also be used by pedestrians, joggers, skaters, wheelchair users (both non-motorized and motorized), equestrians, and other
nonmotorized users. When required, Class I Bikeways shall be designed for two-way traffic and meet the following minimum design criteria: 10.06.1.1.1 Width Standard Class I Bikeways
shall include a fourteen foot (14’) paved section in accordance with Section 10.06.1.1.2. Minimum ten foot (10’) paved width. 10.06.1.1.2 Structural Section Minimum pavement section
of six inches (6”) 6”) of gravel base, two inches (2”) of Crushed Surface Top Course (CSTC), and two inches (2”) of Class “B” asphalt concrete pavement. When the California Bearing Ratio
(CBR) of the existing soil is less that five (5), an additional six inches (6”) of gravel base shall be required. When the trail is also utilized as a service road, the Class “B” asphalt
concrete pavement section shall be increased to three inches (3”). 10.06.1.1.3 Geometrics Class I Bikeways shall closely conform to the grades of the adjacent street and meet the geometric
design standards of AASHTO’s “Guide for the Development of Bicycle Facilities 1999”. 10.06.1.1.4 Buffer Class I Bikeways shall have a minimum five foot (5’) landscape buffer located
between the bikeway and any adjacent street. 12/21/2009 ............................................ Design Standards.........................................Page 10-30 REF. H\DEVELOPMENT\Design
Standards\Chapter 10 (01-10)
10.06.1.1.5 Driveway Crossings Where Class I Bikeways are intersected by driveways appropriate signing and pavement markings shall be provided consistent with MUTCD requirements for
midblock crossings. 10.06.1.1.6 Ownership Class I Bikeways that are part of the City’s Future Trails and Bicycle Network shall be public and shall be located within the public right-of-way,
tracts or easements. 10.06.1.2 Class II Bikeway Class II Bikeways, or “Bike Lanes,” are incorporated within the street right-of-way. Bike lanes are established on streets in corridors
where there is a current of anticipated bicycle demand and where it would be unsafe for bicyclists to ride in travel lanes. Bike lanes shall be provided in accordance with the Future
Trail and Bicycle Network plan pursuant to the City of Auburn Comprehensive Transportation Plan. Bike lanes are exclusive one-way bicycle facilities delineated by pavement markings and
signing. Bicycle traffic is carried in the same direction as the adjacent motorized vehicle traffic. When required, bike lanes shall meet the following minimum design criteria: 10.06.1.2.1
Width Minimum six foot (6’) paved width as measured from nearest edge of the travel way to face of curb, edge of pavement, or edge of parking lane. 10.06.1.2.2 Structural Section Bike
lanes shall have the same pavement cross-section as the adjacent street. 10.06.1.2.3 Geometrics Class II Bikeways, as part of the street section, shall follow the same geometric design
standards. 10.06.1.3 Class III Bikeway Class III Bikeways, or “Shared Lane,” are facilities shared by bicyclists and motorized vehicles. Class III Bikeways will be utilized, in accordance
with the Future Trail and Bicycle Network plan, on existing streets as interim bike corridors until a Class I or Class II facility can be provided. Class III Bikeways may or may not
be delineated with shared use pavement markings and signage. Generally, lower-speed/lowervolume streets are adequate for bicycle travel, so additional signing and pavement markings for
bicycle use are unnecessary. When required, Class III Bikeways shall meet the following minimum design criteria. 10.06.1.3.1 Width Minimum fourteen foot (14’) paved width as measured
from laneline to face of curb, edge of pavement, or edge of parking lane. 10.06.1.3.2 Structural Section Class III Bikeways shall have the same pavement cross-section as the adjacent
street. 10.06.1.3.3 Geometrics Class III Bikeways, as part of the street section, shall follow the same geometric design standards. 12/21/2009 ............................................
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10.06.1.4 Class IV Bikeway Class IV Bikeways consist of all improved roadways unless otherwise designated as Class I, Class II, or Class III Bikeways. 10.06.2 Bikeways at Railroad Crossings
Railroad-Bikeway grade crossings shall be designed as near perpendicular as possible. If rail crossing is less than forty-five degrees (45°), an additional paved shoulder of sufficient
width shall be provided to permit the bicyclist to cross the track at a safer angle. Where this is not possible and train speeds are low, compressible flangeway fillers will be required.
When not under City control the railroad owner shall be responsible for bicycle crossings. 10.06.3 Bikeways at Roundabouts Class I Bikeways at roundabouts shall be combined with the
adjacent sidewalk, if applicable; to create a single shared use crossing through the roundabout zone. Class II and Class III Bikeways shall be terminated a minimum of sixty-five feet
(65’) in advance of roundabouts using appropriate signing and striping with transitions to the adjacent pedestrian facilities which shall be enhanced through the roundabout zone, consistent
with a Class I Bikeway, to accommodate the shared use with bicycles. 10.06.4 Bikeways at Signalized Intersections Class I Bikeway crossings at signalized intersections shall be combined
with the adjacent sidewalk, if applicable, to create a single shared facility utilizing the protected pedestrian crossing at traffic signals. Class II and Class III Bikeways shall be
provided an optional transition to the adjacent pedestrian facilities a minimum of fifty feet (50’) in advance of traffic signals using appropriate signing and striping. The adjacent
pedestrian facility shall be enhanced to Class I Bikeway standards in advance of the transition point to accommodate the shared use through the intersection. 10.06.5 Bikeways at Unsignalized
Intersections Class I Bikeway crossings at unsignalized intersections shall be combined with the adjacent sidewalk, if applicable, to create a single shared use crossing. Class II Bikeways
shall be delineated in accordance with City of Auburn standard details and MUTCD bike lane requirements for intersections. 10.06.6 Bikeway Pavement Markings, Signing, and Striping Pavement
markings, signing, and striping for bikeways shall be designed in accordance with City of Auburn standard details and Manual of Uniform Traffic Control Devices (MUTCD) requirements.
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10.07 Pavement Design This section of the Standards has been prepared for engineers to use in the design of pavement sections for City streets. The use of the following information will
ensure that paved transportation corridors are adequately built or improved in a uniform and consistent manner. The information contained in Table 10-5 has been established to minimize
the structural failures in streets, due to traffic loadings and/or existing soils conditions. Engineers will be allowed to do their own pavement designs in accordance with the current
AASHTO design procedure and the minimum City requirements supplied in Section 10.07.3. The pavement design information contained herein was established for a complete range of street
and traffic conditions excluding principal arterials. It has been simplified so that extensive data and computer analysis is not necessary for developing pavement designs for most projects.
A separate design study will be required for principal arterials and streets where the daily average traffic count is expected to exceed 15,000 vehicles per day and streets where unusually
heavy truck and bus traffic is expected or encountered, such as freight routes and bus routes. Freight routes are defined in the “City of Auburn Comprehensive Transportation Plan”. Studies
should be performed along the freight route to determine the vehicle mix and volumes. Pavement sections for freight routes are not defined in the following tables and need to be designed
to accommodate anticipated volumes. 10.07.1 Design Requirements 10.07.1.1 Street Classification The classification of a particular street, (i.e. Residential Collector), can be obtained
from the City of Auburn. The classification of a street will be required to determine the volume and mix of vehicles for which it is designed. In some cases where a street has yet to
be designated a specific classification, street pavement should be designed based on the anticipated traffic volume. An anticipated daily traffic count can be obtained from the City
of of Auburn for the street in question or a similar street that functions in the same manner. The City may, however, require the applicant to obtain additional traffic information,
as warranted. 10.07.1.2 Street Subgrade For the purpose of pavement design, the California Bearing Ratio (hereafter referred to as CBR) will be used to classify the type of existing
subgrade soils. CBR’s are used because most independent testing laboratories and geotechnical firms have the ability to provide CBR data. The scope of this section does not cover existing
subgrade with a CBR less than “3”. When the CBR is less than “3”, a Geotechnical Design is required. The subgrade under the proposed street shall have its CBR evaluated by an independent
testing laboratory or geotechnical firm. The existing subgrade shall then be classified as determined in the soils classification section (Section 10.07.3). The proposed roadway shall
have a minimum of one CBR test for every 1,000 feet of road and/or for every obvious change in subgrade material (minimum of two (2) tests per street). 12/21/2009 ....................................
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Prior to placing any street base material, the subgrade shall be rolled and compacted to a minimum of 95% of the maximum density as determined by ASTM D-1557 (Modified Proctor). Any
sections of a roadway that exhibit “pumping” shall be removed to a depth where the pumping ceases and replaced with granular imported material that can be compacted to the required 95%
of the maximum density as determined by ASTM-1557 without pumping, or as directed by a Geotechnical Engineer licensed in the State of Washington. If the existing subgrade is classified
as a poor subgrade, then a geotextile fabric may be required on the subgrade prior to placing any subbase or base materials. The geotextile fabric shall be a woven, permeable fabric
produced for placement in road bases. Other requirements for subgrade grading, including slopes and retaining wall, are covered in Chapter 5. 10.07.1.3 Street Pavement Sections Street
pavement section requirements can be determined by using the pavement design chart in Section 10.07.2. The CBR obtained from the testing or geotechnical firm, the type and class of road
from the City of Auburn, will assist in determining the appropriate chart column. A civil engineer licensed in the State of Washington may also design street pavement sections. However,
the minimum allowable thickness of asphalt will be a two inch (2”) leveling course with a two inch (2”) overlay of class “B” asphalt. The maximum allowable thickness for a single lift
of asphalt shall be two inches (2”) for Class “B” and four inches (4”) for Class “E”. Section 10.07.3 provides additional information on pavement design requirements. 12/21/2009 .....................
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10.07.2 Pavement Section Design Chart The following chart contains the minimum allowed pavement design base on traffic volumes and CBR’s unless otherwise designed by a licensed civil
engineer. Due to high traffic volumes and/or the large amount of truck and bus trips, Principal Arterials, bus routes, and/or freight routes, as designated by the City, are not included
and shall be designed on a case-by-case basis. Poor Soils (CBR 3-5) Medium Soils (CBR 6-10) Good Soils (CBR 11-20) Excellent Soils (CBR >20) Private Streets Alleys Access Roads 2” CL
“B” 5” CL “E” 12” Gravel Base 2” CL “B” 2” CL “E” 8” Gravel Base 2” CL “B” 2” CL “E” 6” Gravel Base 2” CL “B” 2” CL “E” 4” Gravel Base Local Residential Rural Residential 2” CL “B” 5”
CL “E” 12” Gravel Base 2” CL “B” 2” CL “E” 8” Gravel Base 2” CL “B” 2” CL “E” 6” Gravel Base 2” CL “B” 2” CL “E” 4” Gravel Base Local Non-Residential 2” CL “B” 5” CL “E” 12” Gravel Base
2” CL “B” 4” CL “E” 8” Gravel Base 2” CL “B” 3” CL “E” 6” Gravel Base 2” CL “B” 2” CL “E” 4” Gravel Base Residential Collectors Rural Collectors 2” CL “B” 5” CL “E” 12” Gravel Base 2”
CL “B” 4” CL “E” 10” Gravel Base 2” CL “B” 3” CL “E” 8” Gravel Base 2” CL “B” 2” CL “E” 6” Gravel Base Non-Residential Collectors 2” CL “B” 6” CL “E” 12” Gravel Base 2” CL “B” 5” CL
“E” 10” Gravel Base 2” CL “B” 4” CL “E” 8” Gravel Base 2” CL “B” 3” CL “E” 6” Gravel Base Minor Arterials 2” CL “B” 8” CL “E” 12” Gravel Base 2” CL “B” 7” CL “E” 10” Gravel Base 2” CL
“B” 6” CL “E” 8” Gravel Base 2” CL “B” 5” CL “E” 6” Gravel Base 12/21/2009 ............................................ Design Standards.........................................Page
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10.07.3 Requirements for Engineered Pavement Sections Engineered pavement designs should follow the latest “AASHTO Guide for Design of Pavement Structures” for flexible pavements and
be based on the following criteria: 10.07.3.1 Traffic Requirements For projects where a traffic analysis report was not required, to determine the amount of traffic for which a street
should be designed, contact the City to obtain the most recent street classification and traffic counts. Traffic counts are done assuming there is a 50/50 split in the direction of traffic.
One hundred percent of the 50/50 split must be assumed in the design lane, regardless of the number of lanes in each direction. (Additional traffic information may be required.) The
existing traffic levels shall then be inflated to match the projected traffic at the end of the roadways design life (in most cases a twenty-year design life will be used). The rate
of growth is one and a half percent (1.5%) for residential streets and three and a half percent (3.5%) for commercial/industrial streets and arterials streets. The one and a half percent
(1.5%) growth can be waived in closed subdivisions with City approval. 10.07.3.2 Pavement Minimums For designers, the minimum allowable thicknesses of pavement sections are as follows:
CL.“B” CL.“E” Gravel Base Minor Arterials 2” 5” 6” Residential/Rural Collectors 2” 2” 6” Residential Streets 2” 2” 4” Local Non-Residential 2” 2” 4” Class E asphalt may be replaced with
crushed rock at a ratio of two to three (every two inches (2”) of asphalt may be replaced with three inches (3”) of crushed rock). At no time however shall asphalt be placed in less
than a two inch (2”) thick lift. Geo-textile fabric may be required between the subgrade and the gravel base where soil conditions are poor. 10.07.3.3 Soils Classifications Prior to
designing the pavement thickness, the soils condition of the area in which the road or street is to be built shall be evaluated and classified into one of the following four different
categories in this this Section. These classifications and the tested soil properties shall then be used in the pavement design. 10.07.3.3.1 Poor Soils These soils are relatively soft
and plastic when wet and may contain appreciable amounts of clays and silts. These soils would be classified as SC, ML, CL, OL, MH, CH, or as OH as per the Unified Soils Classification
System. The CBR values for these materials range from 3 to 5. 12/21/2009 ............................................ Design Standards.........................................Page 10-36
REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10)
10.07.3.3.2 Medium Soils These soils are relatively firm when wet and may contain some amounts of silt. These soils would be classified as SP, SM, or SC as per Unified Soils Classification
System. The CBR value would range from 6 to 10. 10.07.3.3.3 Good Soils These soils retain a substantial amount of their load-bearing capacity when wet. These soils would be classified
as GM, GC, SW, or SM as per the Unified Soils Classification System. The CBR value for these materials may range from 10 to 20. 10.07.3.3.4 Excellent Soils These soils are basically
unaffected by moisture or frost. These soils would be classified as GW, GP, GM, GC, SW, or SM as per the Unified Soils Classification System. The CBR value for these materials would
be greater than 20. 10.07.3.3.5 Unified Soils Classification Symbols GW: Well graded or gravel-sand mixtures with little or no fines. GP: Poorly graded gravels or gravel-sand mixtures
with little or no fines. GM: Silty gravels or gravel-sand mixtures. GC: Clayey gravels or gravel-sand-sand-clay mixtures. SW: Well graded sands or gravelly sands with little or no fines.
SP: Poorly graded sands or gravelly sand mixtures with little or no fines. SM: Silty sands or sand silt mixture. SC: Clayey sands or sand-clay mixtures. ML: Inorganic silts and very
fine sands, rock flour, silty or clayey fine sands or clayey silty that are slightly plastic. CL: Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays,
lean clays. OL: Organic silts and organic silt clays of low plasticity. MH: Inorganic silts, micaceous or diatomaceous fine sand or silty soils, elastic silts. CH: Inorganic clays of
high plasticity, fat clays. OH: Organic clays of medium to high plasticity and organic silts. 10.07.3.4 Report Submittal The applicant must submit a roadway analysis report to the City
of Auburn, including a narrative of the site conditions, the pavement sections, and applicable background information for review and approval. The report must detail data on how the
design was achieved including information on the subgrade soils. (Note: The soils classification in Section 10.07.3.3 is not a substitute for tests to support soil capacity.) 12/21/2009
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10.07.4 Materials Specifications The following material requirements are referenced from the City of Auburn’s Engineering Construction Standards Manual and WSDOT Standard Specifications
and are subject to change. For the most current definitions, please reference the Construction Standards Manual. 10.07.4.1 Gravel Base Gravel base shall be bank run gravel, defined as
naturally occurring material having characteristics such that when compacted in place on the roadway, it will provide a course having greater supporting value than the subgrade on which
it is placed. It shall be from a pit approved by the City Engineer and shall be specified in Division 9-03.10 of the WSDOT Standard Specifications. 10.07.4.2 Crushed Rock Crushed rock
use in City street construction will fall under the following two classifications: A. Crushed Surfacing Top Course (CSTC) B. Crushed Surfacing Base Course (CSBC) CSTC and CSBC shall
be in accordance with Section 9-03.9(3) of the WSDOT Standard Specifications. 10.07.4.3 Asphalt Concrete Pavement Asphalt use in City street construction will typically fall under the
following two classifications: A. HMA Class “E” B. HMA Class “B” Asphalt Concrete Pavement shall be in accordance with WSDOT Standard Specifications and the City’s Engineering Construction
Standards Manual. 10.08 Landscaping 10.08.1 General Landscaping Requirements An area devoted to landscaping is included within the right-of-way of all street classifications. This landscape
strip is an integral part of the roadway cross-section. It serves several important functions, including improving pedestrian safety by providing a buffer between traffic and the sidewalk;
providing the perception of a narrower travel corridor, thereby slowing traffic; improving air quality; and improving the aesthetic appearance of the street. The applicant shall design
and install the landscape strip in accordance with these design standards. The proposed design shall be reviewed and approved by the City. Landscape strips are required for local residential
streets and residential collector streets. The minimum width required for landscape strips is five feet (5’). Landscape strips shall be located between the back of the curb and the sidewalk.
The applicant shall provide for and plant street trees within the landscape strip in accordance with these design standards. 12/21/2009 ............................................ Design
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Street trees are required for principal arterials, minor arterials, non-residential collectors, and local non-residential streets. Street trees shall be placed within the sidewalk in
tree pits with tree grates and spaced in accordance with the standards identified in Section 10.08.5.1. 10.08.2 Landscape Strip Components Landscape strips contain several components.
These include soil, the plants themselves, structural items such as root barriers and tree grates, and may include street furnishings such as luminaries, traffic signs, bus stops or
shelters, benches, and mail boxes. 10.08.3 Landscape Strip Dimensions The roadway sections designate either five-foot (5’) or five and half-foot (5½’) wide landscape strips. 10.08.4
Plant Layers It is recommended that a multi-layer planting be used in the landscape strip. For instance, grass or a ground cover should be used at the ground level, low-growing shrubs
may comprise the next layer, and trees form the upper or canopy level. Within this general framework are many choices, outlined in the Plant Selection section below. In summary, the
landscape strip will contain the following layers: 1. Ground Cover(s) or Grass—Required 2. Shrubs with a mature height of three feet (3’) or less—Optional 3. Trees—Required 10.08.5 Trees
10.08.5.1 Placement and Spacing Trees shall be placed so that they do not obstruct the view of any street intersection, driveway, or visibility of any traffic control device or sign.
Sight distance triangles shall be used to analyze visibility at street intersections. Trees shall be centered in the landscape strip. When a landscape strip is not required, trees shall
be placed in tree pits with tree grates within the sidewalk per City of Auburn Standard Detail TRAFFIC-64. Trees will be spaced as follows, except where special site conditions require
variation for safety or other reasons: Tree Size Height Recommended Spacing Landscape Strip Widths Small To 25 Feet 15 -20 Feet Apart 5 Feet Medium 25 -50 Feet 20 – 30 Feet Apart 5.5
-8 Feet Large 50 – 70 Feet 30 – 50 Feet Apart 8 – 12 Feet Very Large 70 Feet + 50 Feet or Greater 12 Feet + Nearby features such as buildings or overhead wires will also affect where
trees should be located. Minimum size for street trees shall be a two inch (2”) caliper, measured two feet (2’) above the root ball. 12/21/2009 ............................................
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Planting Next to a Building: Where a building is placed close to the sidewalk, the mature size of a tree should be considered when selecting species. Trees with a pyramidal, columnar,
or oval shaped canopy are preferable; a tree with a round head is generally unsuitable in this situation. Overhead Wires: When trees must be planted under utility lines, species with
a maximum height of twenty-five feet (25’) should be selected. Street Lighting: Trees should generally be at least twenty feet (20’) from light standards. Planting locations should be
coordinated with locations of lighting standards. Clearance: Trees shall be pruned as they grow to provide at least seven feet (7’) vertical clearance above sidewalks and fourteen feet
(14’) of vertical clearance above roadway surfaces. 10.08.5.2 Tree Canopy Shape Tree canopy shapes are an important factor in the selection of street trees. The setting will often dictate
which canopy shapes are most appropriate. This in turn will aid in the selection of the most suitable species. The guidance offered below includes information about which tree canopy
shapes work best under different conditions. Table 10-4 offers information about tree species and their canopy shapes. 10.08.5.2.1 V-Shaped Trees V-shaped (sometimes also called “vase
shaped”) trees have canopies that are narrow toward the bottom and broad at the top. The American Elm is a classic street tree with this shape. V-shaped trees may have arching branches
that form a canopy over both street and sidewalk. They generally do not cause problems with overhead power lines or traffic. 10.08.5.2.2 Pyramidal Trees Pyramidal or cone-shaped trees
are typically broad at the base of the canopy and are somewhat pointed at the top. European Beech is one tree that becomes pyramidal with age. Planted close together, pyramidal trees
can screen unwanted views or create vistas. Lower branches sometimes droop with age and may have to be limbed up in later years to provide the needed clearance. 10.08.5.2.3 Round Trees
These are generally wide spreading trees that need more space than other shapes. The Red Sunset Maple is one example of a round tree. 10.08.5.2.4 Oval Trees An oval tree is a good choice
around buildings and adjacent to traffic. Oval trees, like the Raywood Ash, are taller than they are wide and cause little interference with traffic. 10.08.5.2.5 Columnar Trees Columnar
trees are useful in locations where there is little available room between the street and buildings, awnings, or other features. Branches
of columnar trees tend to grow up rather than out. Many branch lower than other types of trees without causing problems with traffic or pedestrians. 12/21/2009 .......................................
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10.08.5.3 Root Direction Devices All street trees planted within a five foot (5’) wide landscape strip shall use a root direction device to deflect tree roots downward into the soil.
These devices are used to eliminate damage to sidewalks as the tree roots extend beyond the original planting pit. The root barrier should be placed along two sides of the tree, parallel
to the sidewalk and to the curb line. Under specific circumstances, wider strips that contain utilities may also need root barriers to reduce conflicts. Plan submissions should indicate
the location of root barriers and provide a specification sheet on the product to be used. 10.08.5.4 Tree Planting Wells and Grates In highly urbanized settings such as downtown, it
may be necessary to install street trees into an existing street and sidewalk setting. Where high levels of pedestrian traffic is expected, it may be necessary to place trees into a
paved area rather than a landscape strip. In these situations planting wells and grates may be necessary. The desirable size for a tree planting well is thirty-six square feet (36 sq.ft.)
or greater. A minimum of twenty-five square feet (25 sq.ft.) should be provided. Where trees are within a heavily traveled pedestrian area, their roots can be easily damaged. In these
areas tree grates or other means such as pavers in sand will be required to protect the health of the tree. Where tree wells or grates are necessary, provide planting details, specifications,
and product sheets for proposed tree-planting wells and tree grates. See Standard Details TRAFFIC-14. 10.08.6 Plant Selection There are innumerable plant choices for each layer of the
landscape strip. Selection is based on: • Size of the landscape strip • Canopy shape of trees • Size and type of leaves • Root shape • Site environmental conditions, such as the amount
of sunlight available or moisture in the soil; and • Aesthetic qualities desired. Needled evergreens, such as firs or spruces, shall NOT be used in landscape strips, unless the strips
are very very wide. Broad-leaved evergreens such as magnolias are acceptable. 10.08.7 Plant Selection Table Table 10-5 provides several acceptable species of ground covers, shrubs less
than 3 feet (3’) high, and a variety of flowering or standard street trees. Many other plants are appropriate; alternative selections may be proposed if desired. Alternative plant choices
will be evaluated and approved by the City. 12/21/2009 ............................................ Design Standards.........................................Page 10-41 REF. H\DEVELOPMENT\Design
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Column Headings: A short description of several of the column headings follows: Size: Small To 25 Feet Medium 25 to 50 Feet Large 50 to 70 Feet Sun: Sun Needs full sun Sun/Shade Takes
sun to part shade; needs at least ½ day of sun Shade Shade to part shade. Protect from full sun, especially in afternoon H20 Req. (Requirement): Low Drought tolerant after 1st year Mod
Moderate water need. May need supplemental watering during dry season. High Requires irrigation Canopy Shape: “V” V-shaped Trees (sometimes also called “vase shaped trees”) Pyramid Pyramidal
trees or cone shaped trees Round Round trees Oval Oval trees Col. Columnar trees 12/21/2009 ............................................ Design Standards.........................................Page
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TABLE 10-5 (TREES) Botanical Name Common Name Size Sun H2O Req. Min. Landscape Strip Width Canopy Shape Remarks Acer campestre Hedge Maple Small/Med Sun/Shade Mod 5-8 Feet Round. Tough
urban plant. Any well-drained soil. Yellow fall color. Broad crown. May need to be limbed up when young. Acer ginnala Amur Maple Small Sun/Shade Low 5-8 Feet “V” Spectacular scarlet
fall color. Fast growing. Tolerant of many soils, pollution, salt and drought. Acer platanoides ‘Armstrong’ ‘Columnare’ ‘Schwedleri’ Norway Maple Large Med Med Large Sun Mod 8-12 Feet
5-8 Feet 5-8 Feet 8-12 Feet Oval Col. Round. Oval Very adaptable to soil and climate condition. Difficult to grow grass under. Many cultivars w/varying heights & shapes. Acer rubrum
‘Red Sunset’ ‘Oct. Glory’ Others available Red Maple Med/Large Sun Mod 5-8 Feet Oval Very adaptable: will grow in swamps or on rocky slopes. Needs shade over root area when used as a
street tree. Carpinus betulus ’Columaris’ European Hornbeam Small/Med Sun/Shade Mod 5-8 Feet Col. Elegant appearance: needs no pruning. Pest & disease free. Cercidyphyllum japonicum
Katsura Tree Med Sun Mod 5-8 Feet Round Beautiful tree w/delicate texture, red tinged leaves, good fall color. Shape varies; can be multi-stemmed. Transplant B&B, early spring. Rich,
moist, well-drained soil. Cercis canadensis Eastern Redbud Small Sun/Shade Mod 5-8 Feet Round. Reddish-purple flowers, early spring. Spreading habit w/flat top. Transplants best when
small. Effective in clusters. Fraxinus oxycarpa ’Golden Desert’ Golden Desert Ash Med Sun Mod 5-8 Feet Oval Small, narrow leaves give a tidy, fernlike appearance. Gold twigs, attractive
in winter. Red to purple fall color. Ginkgo biloba Ginkgo Large Sun Mod 5-8 Feet Col. to Oval Distinctive fan-shaped leaf. Light green foliage in spring; bright yellow in fall. Plant
male trees only. Slow growing. Tolerates wide variety of soil conditions. Liquidambar styraciflua Sweetgum Large Sun Mod 5-8 Feet Col. to Oval Dense canopy of 5-lobed, star shaped leaves.
Yellow to red fall color. Pointed, woody fruit can be a nuisance. Pyrus calleryana and varieties Callery Pear (Flowering Pear) Med Sun Low 5-8 Feet Pyramid to Oval Dark green glossy
leaves in summer, scarlet in fall. Heavy clusters of white flowers in spring. May need corrective pruning when young. Varieties ‘Aristocrat’, ‘Chanticleer’, ‘Redspire’ have a variety
of canopy shapes. Quercus rubra Red Oak Large/Very Large Sun High 8-12 Feet Round Easy to transplant. Needs fertile, welldrained soil, plenty of water. Tolerates pollution. High branching
and fairly open shade make it a good choice for big lawns and blvds. Dark red, or orange fall color. Fast growing. Tilia cordata ‘Greenspire’ Littleleaf Liden Med Sun/Shade Mod 5-8 Feet
Oval/Pyramid Formal look. Upright branching. Needs well-drained, fertile soil. Tolerant of urban conditions. Easy to transplant. Fragrant yellowish flowers in clusters in June. Zelkova
serrata ’Village Green’ Zelkova Med Sun Mod 8-12 Feet ‘V’ Graceful vase-shaped tree resembling the elm. Fair tolerance of soils, best in moist deep loam. Leaves light green in spring,
yellow to russet in fail. 12/21/2009 ............................................ Design Standards.........................................Page 10-43 REF. H\DEVELOPMENT\Design Standards\Chapter
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TABLE 10-5 (GROUND COVER/LOW SHRUBS) Botanical Name Common Name Size Spacing Sun. Min. Landscape Strip Width Flowers Remarks Arctostaphylos una-ursi Kinnikinnick Bearberry Small Sun/Shade
5-8 Feet ♦ Useful on slope, poor or dry soils. Slow to establish; must address early weed problems. C. dammeri Bearberry Cotoneaster 3”-6” Sun/Shade 5-8 Feet ♦ Fast growing, roots freely.
Hedera helix English Ivy 6”-12” 12”-18” Sun/Shade 5-8 Feet Vigorous, should be within a contained area. Will climb vertical surfaces. H. h. ‘Baltica’ Baltic Ivy 6”-12” 12”-18” Sun/Shade
5-8 Feet Smaller leaf than English Ivy; not as aggressive. Hypericum calycinum St. Johns Wort to 12” 18” Sun/Shade 5-8 Feet ♦ Tolerant of poor soils, some drought. Competes well with
trees. Must be in confined space or overtakes other plants. Showy yellow flowers. Vinca minor Periwinkle 6” 12”-18” Shade 5-8 Feet ♦ Needs regular watering. 10.08.8 Planting Methods
and Maintenance Good horticultural practice should be employed in the preparation of the soil and planting pits. This will include: 1. Conserving topsoil and replacing it on the site.
2. Performing soil tests. 3. Providing corrective soil preparation as necessary. 10.08.9 Establishment Period The developer will be responsible for maintaining the trees and plants in
the landscape strip in a healthy condition for one (1) year after acceptance of the project. Because landscape strips do not usually include irrigation, maintenance will include providing
water during dry periods. Weeds, diseases, and insect pests must also be controlled. 10.08.10 Deviations from the Landscape Strip Standards Site conditions may occasionally make adhering
to the landscape strip standards difficult. Deviations from the standards may be requested. The following paragraphs list circumstances that may be appropriate conditions for requesting
a departure from the design standards: Root Direction Device: The root direction device may be omitted if the planting strip is very wide or if the variety of tree to be planted is known
to to cause no sidewalk upheaval. Grass or Ground Cover: Where it is extremely difficult to maintain grass or ground cover in a landscape strip, heavy stone aggregate such as a washed
river rock may be an acceptable substitute. Lightweight rock such as lava rock is not acceptable. Paving over the landscape strip will rarely be acceptable. 12/21/2009 ...............................
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10.09 Mailboxes See Standard Details TRAFFIC-16 thru TRAFFIC-19 Locating and installing mailboxes in connection with the construction or reconstruction of a City street shall follow
AASHTO and Post Office guidelines. 10.09.1 Mailbox Locations Mailboxes shall be located a minimum of two feet (2’) back from the face of curb on streets which have a curb. For streets
without a curb, setbacks shall be determined using ASSHTO standards. When locating mailboxes, access, sight distance, and landscaping requirements shall be taken into account. Final
locations shall be detailed on the civil plans and approved by the serving Post Office and the City. When mailboxes are located in the sidewalk, individually or in clusters, sidewalks
shall be widened to provide a minimum five feet (5’) of clearance around the mailboxes. Widening of the sidewalk may require the dedication of additional right-of way. 10.09.2 Mailbox
Installation The owners or residents served by mailboxes will install and thereafter maintain their own individual, clustered, or separated mailboxes as instructed by the U.S. Postal
Service. Mailbox installation shall follow City of Auburn Standard Details TRAFFIC-16, TRAFFIC-17, TRAFFIC-18, and TRAFFIC-19. 10.10 Illumination 10.10.1 General The City desires to
have safe and uniform lighting standards for streets to allow safe comfortable use by all users. The City has approved standard lighting infrastructure for reliability and ease of parts
inventory and maintenance. Roadway lighting is required along all City owned streets except classified Rural Collectors and Rural Residential. Street lighting design shall be in conformance
with the design criteria in the most recent edition of the IES Lighting Handbook (Illuminating Engineering Society of North America) and applicable WSDOT and City of Auburn Construction
Standards. 10.10.2 Design The City of Auburn prefers staggered lighting on all Principal and Minor Arterials. Single sided lighting may be acceptable if approved by the City. Local Residential
streets will have a choice between a standard light and an ornamental alternative. Table 10-6 has been included as a general guideline for determining illumination sizing and location
requirements. Project specific lighting calculations shall be provided to insure minimum illumination levels will be met. Light level calculations shall be done ignoring any existing
substandard luminares (PSE lights on wood poles, etc.). All poles and bracket arms shall be designed for the street lighting luminaire with a minimum weight of fifty pounds (50 lb.)
and to withstand pressures caused by wind loads of ninety miles per hour (90 mph) with a gust factor of 1.3. Special consideration shall be given for light levels at crosswalks, curves,
conflict points and street ends and shall be designed to meet the minimum light level of 0.2 foot candle. Roadway lighting levels also are impacted by the type of pavement surfacing
and special consideration shall be given for surfaces like concrete roadways. 12/21/2009 ............................................ Design Standards.........................................Page
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12/21/2009 ............................................ Design Standards.........................................Page 10-46 REF. H\DEVELOPMENT\Design Standards\Chapter 10 (01-10) When
pedestrian lighting is used the street light design shall be done independent from the influence of the pedestrian lighting. Pedestrian light spacing shall not exceed five times the
mounting height. When pedestrian lighting is installed, sidewalk lighting shall be designed for two foot (2’) candles. All illumination plans shall include a lighting schedule. Each
luminaire shall be numbered such that the circuit number, the mounting height, davit length and wattage are clearly indicated. For Boulevard streets, streets with median islands, double
arm street lights in the median may be allowed meeting all applicable design criteria of these standards. In addition, access accommodations allowing for light maintenance vehicles to
park outside the travel way must be incorporated into the median island design. The locations of street lights shall take into consideration any obstacles which may screen or impede
lighting levels such as street trees and awnings. Street trees shall be located a minimum of twenty feet (20’) from all streetlights. 10.10.3 Table 10-6 Lighting Schedule The following
Light Spacing is based on the roadway classifications for a typical straight roadway section with a staggered lighting configuration. Wider road sections, curves, intersections, cul-de-sacs
and single sided lighting configurations must use a calculated design meeting the criteria on Table 10-6 with the exception of the Spacing criteria. TABLE 10-6 Street Classification
Street Width (feet) Lamp Wattage Average Maintained Light Level (footcandle) Required Uniformity Ratio Minimum Light Level (footcandle) Luminaire Mounting Height (feet) Light Pattern
Davit Arm Length (feet) Spacing (feet) Principal Arterial 61 400 1.4 3 To 1 0.2 35 40 M-C III 12 190 Minor Arterial 50/61 250 0.9 3 To 1 0.2 35 M-C III 10 190 Non-Residential Collector
44 250 0.9 3 To 1 0.2 35 M-C III 6 200 Residential Collector 34 150 0.6 3 To 1 0.2 30 M-C III 6 175 Local Non-Residential 34 150 0.6 3 To 1 0.2 35 M-C III 6 160 Rural Collector* Local
Residential 28 100 0.4 6 To 1 0.1 30 M-C III 8 185 Local Residential Ornamental Alternative 28 100 0.4 6 To 1 0.1 12 M-C III N/A 140 *Illuminate Signalized Intersections only. For downtown
pedestrian lighting requirements, contact the City of Auburn.
10.10.4 Light Standard Foundations See Standard Detail TRAFFIC-49, TRAFFIC-61 & TRAFFIC-63 All light poles shall be placed on a foundation. Foundations for light standards shall conform
to Standard Detail TRAFFIC-49, or TRAFFIC-61 and TRAFFIC-63 for the Downtown light standards. Light pole foundations adjacent to sidewalks shall include a four inch (4”) concrete pad
and conform to Standard Detail TRAFFIC-48. 10.10.5 Service Cabinet See Standard Detail TRAFFIC-51 All new luminaires shall be connected on an electrical circuit that is connected to
a power source through a service cabinet. Service cabinets shall conform to Standard Detail TRAFFIC-51 and shall be metered with a photocell installed for luminaire control. The service
cabinet shall be within fifty feet (50’) of the Puget Sound Energy (PSE) point of service connection. Service cabinets should be installed behind the sidewalk when possible at locations
that do not impede maintenance access. The cabinet should be located in the center of the system so so there are a near equal number of lights being served on separate circuits from
each side of the cabinet. The number of luminaires per service will be based upon the type of luminaire and the capacity of the service. Testing may be required to determine if additional
luminaires may be added to an existing service. 10.10.6 Service Cabinet Foundations See Standard Detail TRAFFIC-51 The Service Cabinet foundation shall conform to Standard Detail TRAFFIC-51.
10.10.7 Conduit Street light conduit shall be Schedule 40 PVC-ASTM D1785. All conduits for street crossings shall be Schedule 80 PVC-ASTM D1785. All conduits installed under sidewalk
and driveway areas shall be Schedule 40 PVC-ASTM D1785. Conduit type shall not change within a run. Conduits installed under paved roadway, not crossing the roadway, shall be Schedule
80 PVC-ASTM D1785. Conduits shall have a minimum of twenty-four inches (24”) of cover. The City requires that street light conduit be extended through a property’s frontage for future
expansion of the lighting system. 10.10.8 Junction Boxes See Standard Detail TRAFFIC-50 A. Street Junction boxes shall conform to Standard Detail TRAFFIC-50. Junction boxes shall be
of the type specified on the plans and shall conform to the requirements of WSDOT Standard J-40.10-01. All junction boxes shall be locking. B. Type 1 junction boxes shall be located
adjacent to the sidewalk within the landscaping strip, if provided, or adjacent to the back of sidewalk if a landscape strip does not exist, or within the shoulder of a non-curbed roadway.
10.10.9 Light Standards A. STANDARD LUMINARE See Standard Detail TRAFFIC-49 Lighting standards shall be tapered aluminum, davit-style units, with five feet nine inch (5’9”) radius per
Section 9-29.6(1)A (Lighting Standards and Davit Arms, of the City of Auburn Engineering Construction Standards), and shall 12/21/2009 ............................................ Design
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be installed in conformance with City of Auburn Standard Detail TRAFFIC-48 and TRAFFIC-49. B. DOWNTOWN STREET LIGHTING LUMINARE See Standard Detail TRAFFIC-63 Light standards located
within the Downtown Urban Center as depicted on the Comprehensive Zoning Map shall be a 40 foot Concrete Ameron MBR. C. DOWNTOWN PEDESTRIAN LUMINARE See Standard Detail TRAFFIC-61 &
61a Pedestrian light standards located within the Downtown Urban Center as depicted on the Comprehensive Zoning Map shall be 18 ft concrete Ameron VBR. D. LOCAL RESIDENTIAL ORNAMENTAL
ALTERNATIVE LUMINARE See Standard Detail TRAFFIC-62 The Local Residential Ornamental Alternative light standard shall conform to Standard Detail TRAFFIC-62 and shall be Holophane Wadsworth
series fluted shaft with seventeen-inch (17”) diameter base (W12F4/17CA/BK or DG) and may be used in residential plats in place of the standard luminare. E. ANCHOR BASES Anchor bases
per Section 9-29.6(2) (Anchor Bases, of the City of Auburn Engineering Construction Standards) shall conform to the Standard Detail TRAFFIC-49, TRAFFIC-61, TRAFFIC-62, or TRAFFIC-63.
10.10.10 Light Standard Handholes See Standard Detail TRAFFIC-49 Light Standards handholes shall be four inches by six inches (4”x 6”) nominal non-flush type in accordance with Standard
Detail TRAFFIC-49. 10.10.11 Photoelectric Controls Photocells installed on the service cabinet shall be “SST” Series model “SST-IES” or approved equal in conformance with Section 9-29.11(2)
(Photoelectric Controls) of the City of Auburn Engineering Construction Standards. A bypass switch shall be required inside the service cabinet, clearly marked PE Bypass. One photocell
will be required per service cabinet. 12/21/2009 ............................................ Design Standards............................................ Page 10-48 REF. H\DEVELOPMENT\Design
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10.10.12 Luminaires A. Luminaires shall meet the general requirements of Section 9-29 (Illumination, Signals, Electrical) of the City of Auburn Engineering Construction Standards with
the following modifications: 1. Clear burning high-pressure sodium light sources of the ratings shown in the lighting schedule shall be used. 2. Street and Pedestrian Luminaires shall
operate on 240 Volt AC and all luminares shall be full cuttoff. B. All luminaires and circuits shall conform to Table 10-7 below: TABLE 10-7 Wattage Max. LuminairesPer Circuit 100 14
150 12 250 8 400 7 C. All luminaires shall be provided with markers for positive identification of light source and wattage per Section 9-29.10 (Luminaires) of the City of Auburn Engineering
Construction Standards. A maximum of five percent (5%) voltage drop across each circuit will be permitted. Voltage drop calculations will be required for all non-standard illumination
systems. 10.11 Survey Monuments Standard Details TRAFFIC-20 thru TRAFFIC-22 Survey monuments shall be placed or replaced in accordance with good practice in land surveying. Monuments
are required along the centerline of improvement of all new or reconstructed streets. Monuments shall be placed at intersections, P.C. (points of curvature), and P.T. (points of tangency).
All existing survey monuments that are disturbed, lost, or destroyed during construction shall be replaced by a registered land surveyor registered in the State of Washington at the
expense of the responsible builder or developer. 10.12 Guardrail Evaluation of embankments for guardrail installations shall be in accordance with Chapter 710 of the WSDOT Design Manual.
Guardrail installations shall conform to WSDOT/APWA Plan C-1, Beam Guardrail Type 1. End anchors shall conform to WSDOT/APWA Plan C-6, Beam Guardrail Anchor Type 1. 12/21/2009 .......................
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10.13 Bollards Standard Detail TRAFFIC-06 When necessary to deny vehicle access to an easement, tract, or trail (except for maintenance or emergency vehicles) the point of access shall
be closed by a line of bollards. These shall include one or more fixed bollards on each side of the traveled way and removable, locking bollards across the traveled way. Spacing shall
provide one bollard on centerline of the trail and other bollards at a maximum spacing of three feet (3’) to preclude vehicular access. Bollard design shall be in conformance with Standard
Detail TRAFFIC-06. Fire access roads shall not be blocked in this manner without the concurrence of the Fire Marshal. Bollards shall be ten feet (10’) from the paved edge of roadway.
10.14 Transit Stops This section provides the minimum design standards to be used in the design of bus transit facilities in the City of Auburn. Bus facilities shall be designed, located
and installed in cooperation with appropriate operating transit agency. When determined appropriate by the City Engineer, or if comments are made by a transit service agency, an applicant
for new or expanded development is encouraged to consult with King County METRO, or Pierce Transit to determine the practicality of how the site can be served by transit oriented improvements
such as bus pullouts, bus stops, or other appurtenances. 10.14.1 Bus Pullout Requirements Bus pullout lanes may be required where bus queuing or staging is required by the transit agencies
operations and at the discretion of the City Engineer. The following are guidelines that would indicate pullouts would be appropriate: A. Traffic and passenger boarding and debarking
conditions warrant. B. Traffic flow would be greatly hindered due to in lane stopping. C. The posted speed limit is in excess of thirty miles per hour (30 mph). 10.14.2 Locations for
Bus Pullouts Bus pullout locations shall meet the following requirements: A. Placement of bus pullouts shall be on the far side of signalized intersections and non-signalized intersections
immediately following the intersection. Distance between pullouts should not be less than one thousand feet (1000’). B. If far side pullouts are not possible, nearside pullouts will
be evaluated. Mid-block pullouts are discouraged. If a situation arises where a mid-block bus pullout is the only option, pullouts should be constructed on both sides of a two-way street
in a complementary pair. C. Maintaining adequate separation between access points, intersections, and bus pullouts can increase the safety and efficiency of both the roadway and the
transit service. 12/21/2009 ............................................ Design Standards............................................ Page 10-50 REF. H\DEVELOPMENT\Design Standards\Chapter
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D. When locating a bus pullout consideration shall be given to existing access points and where passengers have safe and direct access to sidewalks, crosswalks, ramps, or other pedestrian
facilities. Consideration shall also be given to trip attractors, and activity centers. E. Bus pullouts must meet sight distance requirements. See Section 10.03. 10.14.3 Design of Bus
Pullouts Bus Pullouts shall be designed in accordance with the applicable operating transit agency’s guidelines. Designs must follow applicable guidelines for facilities used by the
physically challenged (Americans with Disabilities Act). The King County Metro Transit Planning Office or Pierce County Transit should be contacted for specific design questions. 10.14.4
Bus Stop Requirements Bus stops are located, designed and installed as part of a cooperative effort between the City and the operating transit agency. Bus stops are managed as part of
a right of way use permit granted by the City to the operating transit agency. In general bus stop location and design decisions should follow the facility design guidelines of the operating
transit agency. The King County Metro Transit Planning Office or Pierce County Transit should be contacted for specific design questions. 10.14.5 Locations for Bus Stops In general bus
stop location and design decisions should follow the facility design guidelines of the operating transit agency. The following are guidelines that indicate where bus stops are appropriate:
A. Projected or existing passenger boarding and debarking demand warrant a stop. B. Traffic characteristics and street design make the location safe to stop a transit vehicle. C. The
location meets the facility guidelines and fleet specifications of the operating transit agency. D. The stop is required to be accessible to the physically challenged (Americans with
Disabilities Act). 10.14.6 Bus Stops Features In general bus stop location and design decisions should follow the facility design guidelines of the operating transit agency. The following
are some guidelines that would indicate what type of treatment would be appropriate by type of bus stop. A. Shelters should be installed at bus stops with an existing or estimated 25
or more boardings per day. B. Benches should be installed at bus stops with an existing or estimated 15 or more boardings per day. C. Trash receptacles should be installed and maintained
by the operating transit agency at all bus shelters. A sign should be placed indicating that the shelter stop is maintained by the operating transit agency and giving specific contact
information to report problems with the stop including a phone number. D. At all bus stops experiencing 15 or more boardings per day trash receptacles may be placed by the City or adopt
a spot group and should be maintained by the City or the adopt a stop group. 12/21/2009 ............................................ Design Standards............................................
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E. Information schedules and schedule holders shall be placed at all inbound stops (stops where buses are headed toward a major Central Business District), at all transfer points and
at heavily used outbound stops. F. Additional bus stop lighting should be provided at locations where lighting levels are determined to be less than 3 foot candles. G. The stop should
be accessible to the physically challenged (meeting the requirements of the Americans with Disabilities Act). 10.15 Traffic Control Devices Traffic Control devices are all signs, signals,
markings and other devices used to regulate, warn, or guide traffic. All traffic control devices shall meet the requirements of FHWA’s latest adopted version of the Manual on Uniform
Traffic Control Devices (MUTCD) and the standards herein. 10.15.1 Median Islands Median Islands are raised barriers constructed between opposing lanes of travel. Median Islands are generally
restricted to classified roadways and may be required in order to: 1. Control access along a corridor, or 2. Provide a traffic calming element. 10.15.1.1 Median Island Design Median
Islands shall be designed using the same geometric criteria as the street on which they will be constructed. Medians shall also meet the following requirements: A. Median Ends: Median
ends shall be flared at intersections and at breaks to allow for transitioning traffic, ease of street sweeping and shall include signage in accordance with MUTCD requirements. B. Width:
Median islands shall be a minimum curb to curb width of eight feet (8’) when landscaped and a minimum of four feet (4’) in width when paved. C. Shy Distance: One foot (1’) minimum shy
distance shall be maintained from face of median curbs to edge of travel lanes. D. Landscaping/Paving: Landscaping in medians shall conform to the requirements of Section 10.08. Median
paving shall be stamped asphalt with colors and patterns approved by the City. E. Irrigation: Landscaped medians shall include irrigation systems. F. Illumination: Street lights on streets
with median islands eight feet (8’) in width and greater shall be located in the medians using dual arm posts and shall meet the minimum light level requirements of Section 10.10. G.
Maintenance Access: Median islands eight feet (8’) in width and greater shall provide a paved maintenance staging area fifty feet (50’) in length with mountable curbs. Median islands
smaller than eight feet (8’) in width shall include one fifty foot (50’) break in the median per block. 12/21/2009 ............................................ Design Standards.......................
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10.15.2 Traffic “C” Curbs Traffic “C” Curbs are barrier curbs used for the restriction of turning movements and to aid in the channelizing of traffic, Traffic “C” curbs may be required
in order to control access along a corridor within the restricted zones of any functional intersection boundary as defined in Section 10.04. 10.15.2.1 Traffic “C” Curb Design Traffic
“C” Curb layout shall be designed using the geometric criteria for channelization. An approved list of barrier curb products can be obtained from the Public Works Department. Use of
any Traffic “C” Curb products not on the approved list must be approved by the City Engineer and meet the following requirements: A. Shall be a National Cooperative Highway Research
Program (NCHRP 350) approved product. B. Shall be constructed of all-weather, shatter and crumble resistant materials. C. Shall not restrict the flow of street surface drainage. D. Shall
include MUTCD compliant reflective markings and vertical channelizing devices. 10.15.3 “Pork Chop” Islands “Pork Chop” Islands are barrier islands used to restrict turning movements
at driveways. They may be required at any driveway where left turns are restricted and Median Islands or Traffic “C” Curb installation is not feasible. When required, Pork Chops shall
be accompanied by appropriate turn restriction signing and pavement markings. 10.15.4 Signing All signing shall be per the “Manual on Uniform Traffic Control Devices” (MUTCD) and City
of Auburn Engineering Construction Standards. Developments shall be responsible for providing and installing all traffic control signs, including but not limited to street name signs,
regulatory signs, warning signs, barricades, and bicycle/pedestrian signs as required. 10.15.5 Pavement Markings See Standard Detail TRAFFIC-35 Pavement markings, raised markers, or
striping shall be used to delineate channelization, lane endings, crosswalks, and longitudinal lines to regulate, warn or guide traffic. The City shall approve all channelization plans
and crosswalk locations. 10.15.5.1 Crosswalks See Standard Details TRAFFIC-36 thru TRAFFIC-38 & TRAFFIC-58 Crosswalks shall be installed at all intersections controlled by traffic signals
and other areas approved by the City. Crosswalks shall be a piano key design consisting of white thermoplastic material. The position of the crossbars should be spaced in such a way
as to allow the majority of wheel traffic to pass in the unpainted space. 10.15.5.2 Left-turn Channelization See Standard Detail TRAFFIC-40 & 42 Left-turn channelization shall include
a minimum of one hundred fifty feet (150’) of fullwidth lane to include storage and a reverse curve ninety feet (90’) in length for posted speed up to forty-five miles per hour (45 mph).
The reverse curve may be included in the taper distance. The standard width of a left-turn lane will be eleven feet (11’). Left-turn arrows per Standard Detail TRAFFIC-35 shall be installed
twenty-five feet 12/21/2009 ............................................ Design Standards............................................ Page 10-53 REF. H\DEVELOPMENT\Design Standards\Chapter
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(25’) behind the stop bar. Additional storage may be required for long vehicles or anticipated left-turn queues longer than the minimum storage. If storage length exceeds one hundred
fifty feet (150’), auxiliary turn arrows will be installed at one hundred foot (100’) intervals. Deviation requests from the minimum left turn lane storage requirements will need a traffic
study submittal and approval by the City Engineer. 10.15.5.3 Left-turn Lane at End of Two-way Left-turn Lane See Standard Detail TRAFFIC 39 Left-turn lane at the end of two-way left-turn
lanes shall conform to Standard Detail TRAFFIC-39. 10.15.5.4 Lane Division See Standard Detail TRAFFIC-43 All pavement markings used to separate or channelize traffic shall conform to
Standard Detail TRAFFIC-43. 10.15.5.5 Painted Islands Painted islands will be allowed on a case-by-case basis with approval from the City Engineer. Pavement markings for painted islands
shall meet the MUTCD requirements. 10.15.5.6 Two-way Left-turn Lanes See Standard Detail TRAFFIC-40 & -41 The installation of two-way left-turn lanes on City streets will be determined
by the City based on street classifications and left turn requirements. The minimum width of a two-way left-turn lane shall be eleven feet (11’). The delineation lines shall be SBY (Single
Broken Yellow) and a SSY (Single Solid Yellow) along the opposing lanes per the MUTCD. Two-way traffic arrows shall be spaced every one hundred fifty feet (150’) along this lane. The
designer should pay special attention to the beginning and endings of this type of lane and use clearly defined tapers or islands to maintain traffic safety. 10.15.6 Construction Area
Temporary Traffic Control The contractor shall be responsible to provide and maintain all signs, barriers, warning lights, striping, and flag control required for maintaining public
safety in construction areas. Traffic control shall be maintained at all times when construction is in progress on all streets, and access points in the construction area. Construction
activities will not be allowed in the public right of way without an approved traffic control plan. 10.16 Roadway Barricades Standard Detail TRAFFIC-05 Temporary and permanent barricades
shall conform to the standards described in Section 6C-8 of the Manual on Uniform Traffic Control Devices (MUTCD) and Standard Detail TRAFFIC-05. A. Type I or Type II barricades may
be used when traffic is maintained through an area being constructed/reconstructed. B. Type III barricades may be used when streets are closed to traffic. Type III barricades may extend
completely across the street (as a fence). Where provision must be made for access of equipment and authorized vehicles, the Type III barricades may be provided with movable sections
that can be closed when work is not in progress, or with indirect openings that will discourage public entry. Where job 12/21/2009 ............................................ Design
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site access is provided through the Type III barricades, the developer or contractor shall assure proper closure at the end of each working day. C. In the general case, Type III barricades
shall be installed to close arterials or other through streets hazardous to traffic. They shall also be used to close off lanes where tapers are not sufficiently delineated. D. Type
III barricades shall be used at the end of a local access street terminating abruptly without cul-de-sac bulb or on temporarily stubbed off streets. Each such barricade shall be used
together with an end-of-road marker. 10.17 Traffic Impact Analysis The City of Auburn has established guidelines for Traffic Impact Analysis that are herein adopted by reference. These
guidelines are used to identify capacity and safety concerns, to assist in the evaluation of site design as it relates to traffic engineering issues, and to identify appropriate solutions
and mitigation. To adequately assess a development’s traffic impact, the City Engineer may require a Traffic Impact Analysis. The requirement for a Traffic Impact Analysis will be based
on the size of the development proposed, existing street and intersection conditions, traffic volumes, accident history, safety considerations, community concerns, and other pertinent
factors relating to traffic impacts attributable to the development. 10.17.1 When Traffic Impact Analyses are Required The following is a list of some specific conditions that may dictate
the requirement for preparing a Traffic Impact Analysis. • The development generates more than 30 PM peak hour trips on a corridor. • The development may potentially affect the implementation
of the street system as outlined in the Comprehensive Transportation Plan and Six Year Transportation Improvement Program (TIP), or of any other documented transportation project. •
The development proposes a rezone of the subject property. • The original Traffic Impact Analysis for a future development is outdated due to changes in traffic volumes in the vicinity
of the proposed project or approved pipeline projects or a change in the proposed land use’s trip generation and/or distribution. • The development could potentially affect safety or
requires an analysis to assist in designing appropriate access. 12/21/2009 ............................................ Design Standards............................................ Page
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10.17.2 Elements of a Traffic Impact Analysis Each development traffic review is different and, as such, each traffic study should be cooperatively designed to address the city’s specific
concerns. Traffic impact analyses are therefore required to be scoped by and with the City Engineer. They may include all or some of the following elements: • Corridor Level of Service
analyses, • Intersection Level of Service analyses, • Access point level of service analyses, • Critical gap analyses, • Horizontal and vertical sight distance analyses, • Roundabout
analyses, • Traffic signal warrant analyses, • Stop control warrant analyses, • Turn lane warrant analyses, • Access management design, • Other analyses and information as required by
the City Engineer. 10.17.3 Special Uses Special event land uses which do not exhibit typical trip generation characteristics may require unique analysis, including but not limited to
weekend and off-peak scenarios, and AM versus PM time frames. Examples of such uses would be concert stadiums, racetracks or uses which exhibit substantial traffic peaking associated
with special events that are scheduled on a periodic basis. The traffic analysis for such uses may include a traffic management plan to control traffic impacts associated with the special
events. 10.17.4 Mitigation Identification In order to protect the public from potentially adverse impacts of the proposal, to fulfill an identified need for public services within the
impacted area related to the development, or both, the Traffic Impact Analysis shall identify methods of mitigating on-site and off-site deficiencies for present and proposed phases
of the development. The analysis shall make recommendations for improvements necessary for safe and efficient traffic flow and bicycle, pedestrian, and transit movement and access proportional
to the identified impacts. Build-out Year, Long-Range Forecast Year, and project phasing impacts shall be considered. All or some of the following items are to be included in the mitigation
identification: • Methods for mitigating on-site impacts and mitigation recommendations, • Methods for mitigating off-site impacts and mitigation recommendations, • Discussion of whether
on-site and off-site improvements are justified, reasonably related to, and proportional to the impacts of the proposed development, • Any requirements or mitigation measures associated
with the Area Circulation Plan. 12/21/2009 ............................................ Design Standards............................................ Page 10-56 REF. H\DEVELOPMENT\Design
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10.17.5 Recommendations The Traffic Impact Analysis report shall clearly state the mitigation measures recommended by the analysis and shall summarize how the recommended mitigations
are proportional to the identified impacts. The recommended street and highway mitigation measures shall be explained in sufficient detail in the analysis to allow them to be understood
and evaluated. The recommendation shall also include the following: • Clear statements of the applicant’s recommended mitigation measures. • Scaled drawings depicting recommended mitigation
improvements and their relationship to existing and proposed conditions if drawings are needed. 10.17.6 Area Circulation Plan Area Circulation Plans are plans which support the development
of a multi-modal transportation network with safe, efficient and pleasant routes for pedestrians, bicyclists, transit users, and motor vehicle occupants. The plan recognizes the link
between land use and transportation planning and promotes land use and development patterns that encourage walking, bicycling, and transit use. The goal of an Area Circulation Plan is
to "provide a transportation system that will facilitate the safe and efficient movement of people and goods throughout the community while supporting the designated Land Uses in the
Comprehensive Plan.” This goal applies to all aspects of circulation including: vehicular, mass transit, bicycle, and pedestrian. In order for the City of Auburn to successfully meet
the vision set forth in the Comprehensive Plan, the Area Circulation Plan will need to address a variety of transportation modes to facilitate the convenient and efficient movement of
people in and near new development. Area Circulation Plans are required for all new development of general commercial and industrial property. They also may be required for land uses
which do not exhibit typical trip generation characteristics that require unique analysis, including but not limited to weekend and off-peak scenarios, and AM versus PM time frames.
The Area Circulation Plan shall include sufficient information to adequately assess the functionality of the proposed development and its impact on surrounding properties and circulation
systems, including but not limited to: • Mapping details, such as site boundaries and dimensions, site acreage, vicinity map, north arrow, scale, title block, etc.; • Access to the site
and interior site circulation; • Proposed lot layout; • Other items which may impact adjacent property, such as general parking arrangement, delivery truck/dock locations, medians or
traffic control devices, median breaks, and other information as deemed necessary by the City Engineer and Planning Director. Any development or subdivision of the property shall generally
be consistent with the Area Circulation Plan as approved or amended. No plat, building permit, or certificate of occupancy shall be issued for the property unless all construction and
development generally conforms to the Area Circulation Plan.
10.18 Table 10-1 Summary Matrix of Minimum Street Design Requirements CLASSIFICATION SECTION PRINCIPAL ARTERIAL MINOR ARTERIAL RESIDENTIAL COLLECTOR NON-RESIDENTIAL COLLECTOR RURAL COLLECTOR
LOCAL RESIDENTIAL LOCAL NON-RESIDENTIAL RURAL RESIDENTIAL Roadway Section Standard Detail No. TRAFFIC-27 TRAFFIC-28 TRAFFIC-29 TRAFFIC-30 TRAFFIC-31 TRAFFIC-32 TRAFFIC-33 TRAFFIC-34
Average Daily Traffic (ADT) 10.01 Over 15,000 10,000 – 15,000 2,500 – 10,000 2,500 – 5,000 1,000 – 5,000 Up to 1,200 Up to 1,200 Up to 1,000 RIGHT-OF-WAY Width (ft) 10.02.9 876 71/826
556 65 60 50 55 50 Intersection Radii-Min. (ft) 10.02.9 39.5 29.5 19.5 24.5 17 9 24.5 7 TRAVELWAY Roadway Width (ft) 10.02.9 616 50/616 346 44 28 28 34 24 Curb/Gutter 10.02.9.4 Y Y Y
Y N Y Y N Number Of Lanes 10.01 5 4/5* 2/3* 3 2 2 2 2 Inside Through Lane Width (ft) 10.02.9.1 11 11 N/A N/A N/A 10 N/A N/A Curb Lane Width (ft) 10.02.9.1 14 14 11.5 16 14 10 17 12 Center
Turn Lane Width (ft) 10.02.9.2 11 11 11 12 N/A N/A N/A N/A Bikeway Class/Width (ft) 5 10.06 Cl. 1 /10 Cl. 1 /10 Cl. 2 /6 N/A Cl. 3 N/A N/A N/A Intersection Curb Radii (ft)1 10.02.9.6
50 40 30 35 30 20 35 20 Parking Allowed 10.02.9.5 N N N N N Y, one-side N Y/two-sides4 ROADSIDE Shoulder Width (ft) 10.02.9.4 N/A N/A N/A N/A 8 N/A N/A 3 Sidewalk Width (ft) 10.05.1
10 10 5 10 0 5 10 0 Street Trees with Grates 10.08 Y Y N/A Y N/A N/A Y N/A Landscape Strip Width (ft) 10.08.1 5 w/Cl. 1 trail5 5 w/Cl. 1 trail 5 5 N/A N/A 5.5 N/A N/A Illumination 10.10
Y Y Y Y Only at Intersections Y Y Only at Intersections INTERSECTION Min/Max Horizontal Approach Angle 10.04.1.2 90° ± 5° 90° ± 5° 90° ± 5° 90° ± 5° 90° ± 5° 90° ± 5° 90° ± 5° 90° ±
5° Minimum Landing Approach Length (ft) 10.04.1.5 30 30 20 20 20 20 20 20 Maximum Landing Approach Grade (%) 10.04.1.5 3 3 5 5 5 5 5 5 GEOMETRIC DESIGN CRITERIA Posted Speed (mph) 2
10.02.7 45 40 35 35 30 30 30 40 35 30 25 30 25 Design Speed (mph) 2 10.02.7 55 50 45 45 40 35 35 45 40 35 30 35 30 Min. Horizontal Curve Radius (ft)2, 8 (For Standard Cross Section)
10.02.1 9720 8150 4930 1121 821 544 544 1125 821 544 333 510 333 Min. Tangent Between Reverse Curves (ft) 2 10.02.2 150 150 150 150 150 100 150 100 Maximum Rate of Superelevation, e
(%) 10.02.3 8 8 0 0 8 0 0 0 Max. Vertical Grade (%)2, 3,7 10.02.4 6 6 8 8 8 8 8 8 Cross Slope (%) 10.02.6 3 3 3 3 3 2 2 2 DRAINAGE Closed System 6.00 Y Y Y Y Only at Driveways Y Y Only
at Driveways Open System 6.00 Y Y * Minor Arterials may be designed as either a four (4) lane road (two lanes in either direction) or a five (5) lane road (two lanes in either direction
and a center turn lane) based on the Comprehensive Plan designation. Residential Collectors may be designed as either a two (2) (one lane in either direction) or three (3) (one lane
in either direction and a center turn lane) lane road based on the configuration of access points to the collector system. 1 At intersections with two different street classifications,
use the highest classification for curb radii. 2 Table values are for standard cross sections with a relatively level grade grade and are for reference only. For accurate design values
reference the AASHTO Manual “A Policy on Geometric Design of Highways & Streets.” 3 Vertical curves will be required when the algebraic grade difference is more than 1%. 4 Parking shall
be located where space is available, outside of the required three-foot (3’) shoulder. 5 The construction of separated bikeways shall be required in conjunction with street projects
when designated by the Comprehensive Plan. 6 Required pavement and right-of-way widths may be greater then that shown to accommodate medians and/or bike lanes as required to meet Comprehensive
Plan designations or to address traffic calming. See Section 10.06. 7 Vertical grades may be increased to 10% for non-arterial streets upon approval of the City Engineer. 8 Minimum radii
are for streets designed using the recommended cross slopes listed above. Minimum street radii for Arterials and rural Collectors may be reduced by superelevating the street section
per the requirements above. 12/21/09 ...........................................................................................................................................................
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Chapter 11 – Site Design 11.00 Preface The design of building sites within the City of Auburn shall conform to the City of Auburn Municipal Code unless modified herein. Compliance with
these standards does not alleviate the design engineer from using sound professional engineering practices. The design criteria contained herein are the minimum acceptable under standard
conditions. Special conditions may require more stringent requirements that will be addressed during the plan review process. The intent of this Chapter is to provide a cross-reference
listing and brief description of the other requirements that may apply to projects that are defined by other Codes and regulations. 11.01 Zoning Code Requirements Title 18 of the Auburn
City Code (Zoning) identifies the regulations that implement the city’s Comprehensive Plan, protect the health safety and welfare of the community, and defines the development standards
(setbacks, height, permitted uses, etc.) applicable to the Zoning District the project is located. The requirements of the Zoning Code are in addition to all of the requirements to this
manual. 11.01.1 Building Setbacks and Lot Orientation Requirements Each zoning district within the City defines the building setback to streets and interior property lines. While the
required setbacks vary for each Zoning District (please refer the “development standards” applicable to each zone, Auburn City Code 18.06 to 18.44) the lot orientation requirements remain
the same, in accordance with Auburn City Code 18.04.570. The front yard setback is measured from the property lines along the right-of-way. When the property has frontage on more than
one street and one of those streets is street classified by the city’s Comprehensive Transportation Plan as an “arterial,” the front yard setback is always measured from that edge of
right-of-way. If the parcel fronts more than one street and more than one of those streets, or none of those streets, are classified as an “arterial,” the front yard setback is determined
by the applicant. If the property does not have street frontage and is accessed by a private easement, coordination is required with the Planning Department for the application of building
setback requirements for the parcel. Please keep in mind that other requirements of the Zoning Code may require an additional building setback beyond the development standards of the
specific zone. 11.01.2 Landscaping Landscaping is a Code requirement applied to projects in the majority of zones within the city. The general intent of the city’s landscaping provisions
is to maintain and protect property values, provide visual unity, improve the character of areas, replace vegetation lost during development, and in some cases create visual screens
or buffers. Auburn City Code 18.50 defines both the requirements of landscaping in each zone (plant spacing, landscaping width, and plant size) and the characteristics of plant 8/9/2004
Design Standards Page 11-01 REF. H\DEVELOPMENT\Design Standards\Chapter 11 (8-04)
spacing. Each of these requirements varies depending on the zone the project is located within, the zones adjacent to the parcel, and the type of uses being proposed on the parcel. For
example, in zones that permit outdoor storage areas, the landscaping Code requires screening of those storage areas. Please contact the Planning Department with questions related to
the landscape requirements of the project. 11.01.3 On-Site Parking Requirements Code-required parking is based on the land use of the property. Auburn City Code 18.52 defines the number
of stalls required for each land use and the size of stall required when using ninety degrees (90°) or some other adopted angled parking stall. 11.02 Land Use Approvals 11.02.1 Subdivisions
Auburn City Code Title 17 defines the regulations applicable to preparing and processing applications for subdivision. A preliminary plat application is filed when applicants seek to
create five (5) or more lots. This application requires preliminary approval followed by construction of the improvements (installation of utilities, roads, etc.). A final plat application
is also required which will demonstrate the construction has been completed in accordance with the approved preliminary plat. The City Council must approve both applications. A short
subdivision application is filed when applicants seek to create four (4) lots or less. Before the City can approve the application, the applicant must complete or guarantee all the required
subdivision improvements. The City relies on a one-step process for short subdivision applications. Please review the applicable requirements from Title 17 before filing your applications.
Please contact the Planning Department with any questions. 11.02.2 Planned Unit Developments The City has adopted Planned Unit Development (PUD) regulations to allow for a greater flexibility
in design for some projects. To qualify, the property must be at least 10-acres in size unless it contains environmentally sensitive areas or features of importance to the neighborhood
or community that warrants preservation or is located on sites adjacent or contiguous to an existing PUD such that the new proposal will function as an extension of that PUD. Auburn
City Code 18.69 defines the requirements for PUD proposals. Please note that a pre-application meeting is required before the City will accept a PUD application. Please contact the Planning
Department with questions you have related to the PUD Code or the pre-application meeting process. 11.02.3 Gated Communities Provisions for gated communities were adopted in 2002 to
provide for additional flexibility in designing quality residential projects. While Auburn City Code 18.48 does define the Zoning Code requirements for gated communities, it is important
to remember that all applicable provisions of the Zoning Code apply in addition to the requirements of this manual. Please contact the Planning Department with questions you may have
related to gated communities. 8/9/2004 Design Standards Page 11-02 REF. H\DEVELOPMENT\Design Standards\Chapter 11 (8-04)
8/9/2004 Design Standards Page 11-03 REF. H\DEVELOPMENT\Design Standards\Chapter 11 (8-04) 11.03 Other Site Design Criteria This Chapter will in the future also contain information on
the following: • Garbage dumpster locations and design. • ADA Accessibility. • Building related issues. • On-site traffic circulation. • Fences. • Other.
Chapter 12 – City Telecommunication Utility 12.00 Preface The design of City Telecommunications facilities located within City right-of-way shall be in conformance with these standards.
Compliance with these standards does not alleviate the design engineer from using sound professional engineering practices. The design criteria contained herein are the minimum acceptable
under standard conditions. Special conditions may require more stringent requirements that will be addressed during the plan review process. City telecommunications facilities shall
be included in the Facility Extension Agreement (FAC) between the developer and the City
when the Agreement includes street improvements per ACC 12.64. 12.01 Design Criteria The City has established the following minimum requirements to ensure the efficient construction
of City telecommunication utilities with the least impact to City transportation and other utility infrastructure. The design of City telecommunications facilities shall also meet the
requirements of Section 9.01.2, Public and Private Utilities Located Underground Within City Right-of-Way with the exception that a construction permit is not required if this work is
completed as part of a Facility Extension Agreement. City telecommunications facilities may be required in conjunction with street improvements on all roadways classified as Arterial
or Collector. Such facilities, when required, shall be extended the full length of the street improvement. When feasible, placement of the facilities shall accommodate connection with
other existing or future telecommunication facilities within the corridor. 12.01.1 Conduits City telecommunication conduits shall be 3-inch PVC Schedule 40 and shall have a minimum of
24 inches of cover and, except for street crossings, shall be located under the sidewalk per Standard Detail TRAFFIC-54. If no sidewalk is included in the scope of the required street
improvements, the conduit will be installed in the most feasible location within the street construction limits as directed by the City. Roadway crossings shall be minimized and sweeps
shall be long sweep 90 degree bends. Trace wire shall be placed within the conduit. Conduits shall be placed a minimum of 5 feet from other utilities. 12.01.2 Splice Vaults and Pull
Boxes When required, splice vaults and pull boxes shall be per the standard details GENERAL-05, -05a, -06 and -06a respectively. Splice vaults shall be placed every 1,500 feet. Pull
boxes shall be placed every 500 feet and at all arterial and collector intersections. 10/8/2007 Design Standards Page 12-01 REF. H:\DEVELOPMENT\Manuals\Design Standards\Chapter 12 (10-07)
DEFINITIONS AASHTO -American Association of State Highway and Transportation Officials. Access Point -A driveway or private street that connects to the general public street system.
A public street is not considered an access point. ACP -Asphalt Concrete Pavement. Activity Centers -Locations such as schools, parks, retail areas and shopping centers, places of employment,
or public service areas that attract people. ADT -Average Daily Traffic. The total two-directional volume of traffic passing through a given point during a given time period, divided
by the number of days in that time period. Aggregate -A mixture of various soil components (e.g. sand, gravel, and silt). Alley -Right-of-way, usually narrower than a street with an
all weather surface, which provides access to the rear boundary of two (2) or more residential or non-residential properties and is not intended for general traffic circulation. Applicant
-The owner or their agent seeking approval from the city for any land use or other related permit or approval referenced in City of Auburn Code and which requires utilization of these
Standards. References: See Developer. Appurtenance -Equipment and/or accessories that are a necessary part of an operating utility system or subsystem. APWA -American Public Works Association.
ASTM -American Society for Testing and Materials. Backfill -Replacement of excavated material with suitable material compacted as specified. Backwater -Water held back by some obstruction,
natural or artificial. Backwater Curve -A plot of depth versus location along the channel containing backwater. Bicycle Facilities -A general term referring to improvements that accommodate
or encourage bicycling, including parking facilities, bike racks, bicycle route mapping and bicycle route development. Boring/Jacking -Grade and alignment-controlled mechanical or other
method of installing a pipe or casing under a street without disturbing the surrounding medium. Breakaway Structure or Breakaway Design -A structure or installation that has been crash
tested in accordance with National Cooperative Highway Research Program procedures. (NCHRP 230). Capacity – (1) The maximum number of vehicles that have a reasonable expectation of passing
over a given roadway or section of roadway in one direction during a given time period under prevailing roadway and traffic conditions. (2) The volume of liquid or gas that can be transported
by a pipe. (3) The load-carrying limit of a structure. Carrier -Pipe directly enclosing a transmitted fluid or gas. Casing -A larger pipe enclosing a carrier for the purpose of providing
structural or other protection to the carrier and/or to allow for carrier replacement without re-excavation, jacking or boring. CF -Cubic Feet. 8/9/2004 Design Standards Page D-01 REF.
H:\DEVELOPMENT\Design Standards\Definitions (8-04)
Channelization -The separation or regulation of conflicting traffic movements into definite paths of travel by the use of pavement markings, raised islands or other suitable means to
facilitate the safe and orderly movement of both vehicles and pedestrians. Check -A short section of built-up channel placed in a canal or irrigation ditch and provided with gates or
flashboards to control flow or raise upstream level for diversion. Check Dam – Short berm used as erosion protection on steep drainage ditches. City -The City Engineer or any designee
thereof. References: See City Engineer. City Council -The city legislative authority. City Engineer -The City Engineer for the City of Auburn. References: See Engineer. Clean-Out -A
pipe through which plumbing snakes can be pushed to unplug a sewer. Clear Zone -The total streetside border area, starting at the edge of traveled way, available for safe use by errant
vehicles. This area may consist of a shoulder, a recoverable slope, a non-recoverable slope, and/or a clear run-out area. The desired width is dependent upon the traffic volumes, speeds,
and the streetside geometry. CMP -Corrugated Metal Pipe. Coating -Protective material applied to the exterior of a pipe or conduit to prevent or reduce abrasion and/or corrosion damage.
CY -Cubic Yard. Dedication -The transfer of land or the interest of land by the owner of such land to the City for public uses, reserving no other rights than such are compatible with
the full exercise and enjoyment of the uses the property has been dedicated. Conduit -An enclosed tubular runway for protecting wires or cables. Contractor -The individual, partnership,
firm, corporation or joint venture, contracting with the Developer to do prescribed work. Commercial Property Use -Property with residential developments with four or more dwelling units
per parcel or commercial developments. This is consistent with building permit administration in City of Auburn. Concrete Plain -Concrete that is not reinforced with steel. Concrete
Thrust Blocking – Concrete that is used to support fittings in water mains. Control Zone -That Streetside area defined by the "Control Zone Distance Table"; found in Appendix 5 of the
WSDOT Utilities Manual, within the street right-of-way in which placement of utility objects is controlled. Corporation Stop – A brass fitting used to connect service lines to a water
main. Cover -Depth to top of pipe, conduit, casing or gallery below the grade of a street or ditch. Cross Connection -Connecting fire, irrigation and drinking water supplies together,
or connecting storm and sanitary sewers together. Cul-de-sac -A street closed at one (1) end by widened pavement of sufficient width for vehicles to turn around. CSBC -Crushed Surfacing
Base Course. CSTC -Crushed Surfacing Top Course. 8/9/2004 Design Standards Page D-02 REF. H:\DEVELOPMENT\Design Standards\Definitions (8-04)
Dead End Street -Street that accesses the roadway system only at one end. Dead end streets are permanent conditions and should end in a cul-de-sac where appropriate. See Also Stub End
Street. Design Speed -Design speed is the maximum safe speed that can be maintained when conditions are so favorable that the design features of the highway govern. Detention Tanks and
Vaults -Detention tanks and vaults are underground facilities for the storage of surface water. Tanks are typically constructed from corrugated metal pipe. Vaults are constructed from
reinforced concrete. Detention Time -The average time spent by water in a basin or structure. Developer -The Owner and any agent of the Owner authorized to represent the Owner. References
see Applicant. Development -All structures and other modifications of the natural site above and below ground on a particular site. DHV -Design Hour Volume. Hourly traffic volume used
for street design and capacity analysis, usually one or more peak hours during a 24-hour period. Director -The Director of the City of Auburn Public Works Department or his/her authorized
representative. Drain -Appurtenances to discharge accumulated liquids from casings or other enclosures. Driveway Approach -See Access Point. Easement -A right to use or control the property
of another for designated purposes. Edge of Traveled Way -The face of curb for streets that are, or will be constructed to urban standards and the edge of pavement (not shoulder) for
streets that are, or will be constructed to rural standards. Embankment -A raised structure constructed of natural soil from an excavation or borrow source. Encroachment -Occupancy of
city right-of-way by non-roadway structures or other objects of any kind. Engineer -The City Engineer for City of Auburn or any designee thereof. Force Main -A sewer line that is pressurized.
Franchise -Occupancy and use document granted by the city required for occupancy of street rights of way. Geometrics -The arrangement of the visible elements of a street such as alignment,
grade, sight distance, widths, and slopes. Grade -Rate or percent of change in slope, either ascending or descending from or along the roadway. It is measured along the centerline of
the roadway or access point. Gravity Distribution -A water supply that uses natural flow from an elevated tank or mountain reservoir to supply pressure. Hazard -A side slope, an object,
water, or a drainage device that, if impacted, would apply unacceptable impact forces on the vehicle occupants or place the occupants in a hazardous position. It may be either natural
or man-made. Headwall -Entrance to a culvert or sluiceway. 8/9/2004 Design Standards Page D-03 REF. H:\DEVELOPMENT\Design Standards\Definitions (8-04)
Hydraulic Jump -The rapid change in the depth of flow from a low stage to a high stage resulting in an abrupt rise of water surface. Impervious Layer -A geologic layer through which
no water can pass. Infiltration – (1) The act of stormwater permeating into the ground. (2) Groundwater that enters sewer pipe through cracks and joints, or the movement of water through
the upper soil. Interception -Rain that falls on vegetation and other impervious objects, which evaporates without contributing to the runoff. Intersection Sight Distance -The distance
required for a vehicle, traveling at or near the posted speed on a major street, to reduce speed to avoid overtaking a vehicle, which has entered the intersection from the minor street.
The entering vehicle can be making right, leftturning movements or crossings. Island -A defined area between traffic lanes for control of vehicle movements and/or for pedestrian refuge.
Joint Use Driveway Tract -A jointly owned and maintained tract or easement serving two (2) properties. Landing -A road or driveway approach area to any public or private road. Lateral
-A sewer line that goes off at right angles to another. LF -Linear Feet. Manhole -An opening in an underground utility system into which workers or others may enter for the purpose of
making installations, inspections, repairs, connections, cleaning, and testing. Median -That portion of a divided roadway separating the traveled ways for traffic in opposite directions.
Mode Split -The percentage of overall trips made by different means of transportation. MPH -Miles per hour. MSE Walls -Mechanically Stabilized Earth Walls. MUTCD -The Manual on Uniform
Traffic Control Devices. MVO – Minimum valve opening. NDCBU -Neighborhood Delivery and Collection Box Unit. Outfall -The pipe that discharges completely treated wastewater into a lake,
stream or river. Passing Sight Distance -The minimum sight distance required for the driver of one vehicle to pass another vehicle safely and comfortably. Pavement -The combination of
gravel base, crushed rock, and asphalt concrete pavement placed on a subgrade to support the traffic load and distribute it to the subgrade. Pavement Width -The distance measured from
face of curb to face of curb for curbed sections of roadway or the distance measured from outside edge of shoulder to outside edge of shoulder for shouldered sections of roadway. PC
-Point of Curvature. PCC -Portland Cement Concrete. 8/9/2004 Design Standards Page D-04 REF. H:\DEVELOPMENT\Design Standards\Definitions (8-04)
Peak-Hour -That period experiencing the highest volume of traffic. Peak Period -Two hours during any a.m. or p.m. period when vehicle arrival and departure from the site or corridor
is the highest. Perimeter Streets – Public streets comprising the perimeter of a particular commercial/industrial development. Permit -A document including any license, permit or franchise
authorizing specified use of city right-of-way and granted under the authorization of the regulating agency. Pipe -A structural tubular product designed, tested, and produced for the
transmittance of specific liquids and gases under specific conditions. PI -Point of Intersection. Plowing -Direct burial of utility lines by means of a `plow' type mechanism, which breaks
the ground, places the utility line at a predetermined depth, and closes the break in the ground. Posted Speed -Is the signed speed limit along a street. Potable -Drinkable PRC -Point
of reverse curvature. Pressure -Internal gage pressure in a pipe in pounds per square inch, gage gage (psig). Private Street -A privately owned and maintained access provided for by
a tract, easement or other legal means. Professional Engineer -An engineer licensed to practice in the State of Washington. Professional Land Surveyor -A surveyor licensed to practice
in the State of Washington. Public Street – A publicly owned facility that provides access, including the roadway and all other improvements. PT -Point of Tangency Relocation -Planned
change of location of an existing facility to a more advantageous place without changing the character or general physical nature of the facility. Replacement -Installation of a like
element of a utility system or subsystem in the same or near-same physical location normally due to damage, wear or obsolescence of the element. Restoration -All work necessary to replace,
repair or otherwise restore the right-of-way and all features contained within to the same or equal condition as before any change or construction thereto. Retention Period -See “Detention
Time.” Reviewing Agency -City of Auburn. Restricted Access Point -A driveway or private street that connects to the general public street system, that turning movements are restricted
to right in and out only. Right-of-way (R/W) -All property in which the City has any form of ownership or title and which is held for public street purposes, regardless of whether or
not any street exists thereon or whether or not it is used, improved, or maintained for public travel. Riprap -Pieces of broken stone used to protect the sides of waterways from erosion.
8/9/2004 Design Standards Page D-05 REF. H:\DEVELOPMENT\Design Standards\Definitions (8-04)
Rural -All lands regardless of current comprehensive plan designation not meeting the definition of Urban. Sand Trap -A section constructed deeper than the rest of the channel to allow
sediment to settle out. Separate Turn Lane -An auxiliary lane for traffic in one direction which has been physically separated from the intersection area by a traffic island or stripe.
Separate turn lanes may be included within intersections or separated from intersection areas by traffic islands. SF -Square Feet Shoulder -That portion of the roadway contiguous with
the traveled way for accommodating stopped vehicles, for emergency use, and for lateral support of base and surface courses. Single Main System -One main supplies both drinking water
and fire fighting water. Single Occupancy Vehicle (SOV) -Automobiles transporting the driver only. Slab -A cast concrete member of uniform thickness. Standards – The City of Auburn Design
Standards. Stopping Sight Distance -The distance needed for a vehicle traveling at or near design design speed to stop before reaching a stationary object in its path. Street or Roadway
-A public way, open for the passage of vehicles, persons and animals. Limits include the outside edge of sidewalks, or curbs and gutters, or side ditches, including the appertaining
shoulder and all slopes, ditches, channels, waterways, and other features necessary for proper drainage and protection within the right-of-way. Street Frontage -Any part of private or
public property that borders a public street. Street Tree -A tree placed within the public right-of-way. Stub End Street -A dead end street that is planned to be extended and connected
to future streets in an adjacent development. Depending on its length, it may or may not require a temporary cul-de-sac. Subtended – To be opposite to and delimit <In a triangle, the
hypotenuse subtends a right angle.> Surface Retention -That part of a storm that does not immediately appear as infiltration or surface runoff. Retention is made up of depression storage,
interception interception and evaporation. Time of Concentration -The time required for water to flow from the most distant point on a runoff area to the measurement or collection point.
Traffic Control -Those activities necessary to safeguard the general public, as well as all workers, during the construction and maintenance of roadway and other facilities within the
right-of-way. Traveled Way -That portion of the roadway intended for the movement of vehicles, exclusive of shoulders. Trenched -Installation of a utility in an open excavation. Trip
-A one-direction movement that begins at the origin and ends at the destination. For example, a trip movement from a residence to a work place is a trip from home to work. Trip Generation
-A general term describing the analysis and application of the relationships that exist between the trip makers, the traffic study area, and the trip making. It relates to the number
of trip ends in any part of the traffic study area. 8/9/2004 Design Standards Page D-06 REF. H:\DEVELOPMENT\Design Standards\Definitions (8-04)
8/9/2004 Design Standards Page D-07 REF. H:\DEVELOPMENT\Design Standards\Definitions (8-04) Uniform Flow -Flow that has a constant depth, volume, and shape along its course. Unopened
Right-of-way -A city right-of-way that exists by dedication or deed, but for which no vehicular roadway has been constructed by the city or other parties, and the street is not maintained
by the city. Unrestricted Access Point -A driveway or private street that connects to the general public street system, that has no limitations on turning movements. Left, right turns
in and out are permissible. Untrenched -Installation of a utility without breaking the ground or pavement surface such as by jacking or boring. Utility -A company providing such public
services as gas, electric power, telephone, water, sewer, or cable television, whether or not such company is privately owned or owned by a governmental entity. Vent -Appurtenance to
discharge gaseous contaminants from casings or other enclosures. Wetpond – A stormwater pond that has been designed to retain a permanent pool of water “wetpool” to provide treatment
of storm runoff. Wetpool – The permanent pool of water retained in a wetpond or wetvault. Wetvault – A stormwater vault that has been designed to retain a permanent pool of water “wetpool”
to provide treatment of storm runoff.