HomeMy WebLinkAbout9805140639 STORM EASEMENT 05149i
Return Address:
City of Auburn
City Clerk
25 West Main
Auburn, WA 98001
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STORM WATER EASEMENT AND MAINTENANCE AGREEMENT
(FA00019-97 and GRA0010-97)
Reference # if applicable):
N/A
Additional on page:
.Grantor/Borrower:
1 West Valle Partners LLC
2
Additional on page:
Grantee/AssigneeBeneficia
r:
City of Auburn
Legal Descri tion/STR:
NW 1/4 01-21-04
Additional on page:
S'
Assessor's Tax Parcel ID#:
158260-0095
THIS EASEMENT AGREEMENT made and entered into this ~ -1 day of
_6v- , 19 , by and between the City of Auburn, a municipal corporation of
King County, Washington, hereinafter referred to as "CITY" and West Valley Partners, LLC,
located at 3615 West Valley Highway North, #201, Auburn, WA 98001, hereinafter referred to
as "PROPERTY OWNER".
WHEREAS, PROPERTY OWNER has applied for certain permits with the CITY for the
construction of facilities at 1231 37 Street NW which create impervious surface; and
WHEREAS, the PROPERTY OWNER will complete a storm system; and
WHEREAS, the PROPERTY OWNER and the CITY desire that the storm system be
maintained to provide adequate facilities for controlling both the quantity and quality of storm
drainage; and
WHEREAS, for maintenance of a storm system it is necessary to have appropriate right-
of-way to bring in equipment to conduct maintenance functions; and
WHEREAS, maintenance requirement is a covenant running with the land and binding
upon all heirs, successors and assigns of both parties; and
WHEREAS, the parties desire that this Agreement be recorded to advise heirs, successors
and assigns of both parties as to the existence of this easement and agreement; and
WHEREAS, an easement is needed to bring in maintenance equipment; and
Storm Water Easement and Maintenance Agreement
Page 1 of 30
1 0 f
WHEREAS, the parties are both desirous of permitting inspection of the storm system to
make certain that it is functioning properly and for purposes of determining the appropriate
repairs.
NOW, THEREFORE, BASED UPON MUTUAL COVENANTS TO BE DERIVED
THE PARTIES AGREE AS FOLLOWS:
Section 1, EASEMENT
PROPERTY OWNER hereby provides an easement over, under and on that portion of the
property as showing on the approved Record Drawings revised pursuant to construction records
for the City of Auburn under Permit No. FA00019-97, which Record Drawings are hereby
M incorporated by reference as if set out in full. This easement shall be a burden to that real estate
which is legally described and attached as Exhibit A and incorporated herein by this reference,
and shall be of benefit to the City storm utility system.
Section 2, HEIRS, SUCCESSORS AND ASSIGNS
This Agreement shall be binding upon the heirs, successors and assigns of the parties.
Section 3, MAINTENANCE
The PROPERTY OWNER agrees to maintain the storm system in accordance with the
ordinances and all applicable codes of the CITY and the Stormwater Pollution Prevention
Maintenance and Operation Schedule attached as Exhibit "B" and incorporated herein by this
reference. The PROPERTY OWNER does hereby agree that the CITY may enter onto the
property of the PROPERTY OWNER via the easement described above to inspect and perform
necessary maintenance if, after the PROPERTY OWNER is given notice to maintain, the
PROPERTY OWNER fails to maintain. Further, the PROPERTY OWNER agrees the CITY
may enter onto the property of PROPERTY OWNER via the easement described above to
perform emergency maintenance in the event of the storm system's failure which might result in
adverse impacts(s) on public facilities or private facilities of other property owners. In both
events the PROPERTY OWNER agrees he/she/they/it shall reimburse the CITY for the costs
incurred by the CITY in maintaining the storm system. Should the CITY incur attorney's fees
and/or costs in enforcing the agreement and/or in maintaining or collecting maintenance fees, the
PROPERTY OWNER agrees to pay reasonable attorney's fees and all costs incurred by the
CITY.
Storm Water Easement and Maintenance Agreement
Page 2 of 30
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Section 4, ACKNOWLEDGMENT OF OTHER ENFORCEMENT ACTIONS
PROPERTY OWNER acknowledges that there may be liability for violations of codes
that could result in additional fines and/or the possibility of incarceration in addition to the fees
for maintenance should violations occur.
EXECUTED as of the date first written above.
CITY OF AUBURN
DIRECTOR OF PUBLIC WORKS
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Storm Water Easement and Maintenance Agreement
Page 3 of 30
It
STATE OF WASHINGTON)
)ss.
County of King )
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I certify that I kn w or haw ati fac pry evidence that (~1 kA ~ A 1+A,- -A Q L
and is/are the person(s) who appeared
before me, and said par ner(s) acknowledged that he/she/they signed this instrument and
acknowledged it to be his/her/their free and voluntary act for the uses and purposes mentioned in
this ins ent.
Dated e , /11. /94,
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STATE OF WASHINGTON
)ss.
COUNTY OF KING )
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Notary Pu lic in and for the State of Washington
residing at F)
My appointment expires I 1 -'G
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I certify that I know or have satisfactory evidence that Frank A Currie is the person who
appeared before me, and said person acknowledged that he signed this instrument, on oath stated
that he was authorized to execute the instrument and acknowledged it as the DIRECTOR OF
PUBLIC WORKS of the CITY OF AUBURN to be the free and voluntary act of such party for
the uses and purposes mentioned in this instrument.
Datedi
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Notary Public in and for the~St9te of Washington
residing at
My appointment expires 110
REF. H:\FAC\FAC1973\E97-938 and Y:\PRMSYS\DOCUMENT\GRA0010 .97\SWEASAGR
Storm Water Easement and Maintenance Agreement
Page 4 of 30
EXHIBIT "A"
LEGAL DESCRIPTION
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THAT PORTION OF TRACT 'I" OF TOWN OF CHRISTOPHER AS PER PLAT
RECORDED IN VOLUME 7 OF PLATS, PAGE 30, RECORDS OF KING
COUNTY, DESCRIBED AS FOLLOWS:
BEGINNING AT THE NORTHEAST CORNER OF SAID TRACT '10; THENCE-:`,
NORTH 89' 14' 19' WEST ALONG THE NORTH LINE THEREOF
1,027.82 FEET TO A POINT ON THE NORTH LINE OF SECTION 1,.
TOWNSHIP 21 NORTH, RANGE 4 EAST W.M., DISTANCE 527.81 FEET.:
EASTERLY FROM THE NORTHWEST CORNER OF SAID SECTION; THENCE"
SOUTH 03' 25' 52" WEST, 770.94 FEET TO THE TRUE POINT OF "
BEGNNING; THENCE NORTH 88' 32' 23' WEST, 152.43 FEET; -
THENCE SOUTH 02' 22' 37" WEST, 288.39 FEET. TO THE
NORTHERLY LINE OF SOUTH 292ND STREET; THENCE SOUTH 86' 34'
08' EAST ALONG SAID LINE, 147.03 FEET; THENCE NORTH 03'
25' 52' EAST, 293.58 FEET TO THE TRUE POINT OF BEGINNING;
EXCEPT THAT PORTION THEREOF CONDEMNED FOR STREET/ROAD IN
KING COUNTY SUPERIOR COURT CAUSE NO. 718254, DESCRIBED AS:
THAT PORTION LYING SOUTHERLY AND EASTERLY OF A LINE
DESCRIBED AS FOLLOWS.
BEGINNING AT A POINT 95 FEET DISTANT NORTHERLY, WHEN
MEASURED AT RIGHT ANGLES FROM SAID 37TH STREET LINE SURVEY
AT STATION 10+00; THENCE WESTERLY 321 FEET, MORE OR LESS; TO
A POINT 65 FEET DISTANT NORTHERLY, WHEN MEASURED AT RIGHT
ANGLES FROM SAID 37TH STREET LINE AT STATION 6+80; THENCE
WESTERLY 165 FEET, MORE OR LESS, TO A POINT 60 FEET DISTANT
NORTHERLY, WHEN MEASURED RADIALLY FROM SAID 37TH STREET LINE
AT STATION 5+15; THENCE WESTERLY 135 FEET, MORE OR LESS, TO
A POINT 50 FEET DISTANT NORTHERLY, WHEN MEASURED AT RIGHT
ANGLES AND/OR RADIALLY FROM SAID 37TH STREET LINE AT STATION
3+79.79 P.C.; THENCE NORTH 86' 31'. 00' WEST 125.33 FEET;
THENCE.SOUTH 03' 39' 00" WEST 50 FEET TO A POINT, AND THE
ENO OF THIS LINE DESCRIPTION;
SITUATE IN THE CITY OF AUBURN, COUNTY OF KING, STATE OF
WASHINGTON.
Storm Water Easement and Maintenance Agreement
Page 5 of 30
EXHIBIT "B"
STORMWATER POLLUTION PREVENTION PLAN
for
A & G Machine Building
1231 37th Ave. N.W.
Auburn, WA
SEPA # SEP 0027-97 PAC # PAC 0019-97
GRA # GRA 0010-97 BLD # BLD xxxx-xx
0 Parcel # 158260-0095
O Introduction:
The A & G Machine storm drainage system will comprised of underground
storm drainage detention pipe with a water quality filtering system
located within a concrete vault.
The building is 20,072.5 sf and is located at 1231 37th Street N.W.
Auburn, Washington. The total site area is 0.93 acres. The total
impervious area of the site is assumed to be at 900 or approximately
0.84 acres.
The existing storm drainage system directs surface water runoff via
sheet flow from the roof and parking lot areas of the existing residence
and from the undeveloped open fields to the surrounding soils. No
direct connection to a tightlined public conveyance system has been
observed. However, the development to the west of the site has provided
an 8 inch storm drainage stubout for the property to drain to.
The developed storm drainage runoff is conveyed to the storm water
underground detention system. Stormwater runoff is then routed to the
flow control structure and water quality treatment vault. The treatment
vault is designed and installed by Stormwater Management. Stormwater is
discharged after treatment to the public conveyance system located
within 37th St. N.W. Right-of-Way.
Plan Goal
The specific purpose for the storm water facility is to minimize
pollution that is typically associated with modern development. In
general, pollution from motor vehicles and pollution generated from
erosion. Attached to this narrative is a maintenance manual which
offers guidelines to the owner for storm water facility maintenance.
Storm Water Easement and Maintenance Agreement 1
Page 6 of 30
Preventative BMP'S
The owner shall be responsible for sweeping the lot, installing storm
drainage stenciling and provide spill control procedures. In case of
spill call: Washington State Department Ecology @ 1-(425)-649-7000.
* BMP RO.05 Spill Control (sc-type) Oil/ Water Separator
* BMP RB.15 Detention Tank (underground)
* See (Section 2) regarding the maintenance procedure for Stormwater
management filter system. (attached)
* - These BMP'S will be inspected a minimum of 2 times per year or as
directed in the Maintenance and Operation Manual. The owner shall keep
a record of inspection and maintenance for a period of 5 years and will
provide a copy of the records and maintenance checklist for the City
Inspector to review; if required.
CID
Q The City of Auburn Utilities Section is to review and approve any changes to
qT this stormwater Pollution Prevention Plan prior to changes in its
implementation. Additionally, any changes in ownership or person of
responsibility are to be reported to the City Utilities Sections.
0
Persons of.Responsibility: West, Valley Partners
3615 W. Valley Hwy. Ste. 201
Auburn, WA 98001
Ph # (253) 939-1800
(Changes to ownership shall be reported
to the City of Auburn's Utilities Section.)
Storm Water Easement and Maintenance Agreement
Page 7 of 30
. . N
Inspection: Maintenance:
Regular inspections of the drainage facilities should be carried out twice per
year, in the spring and fall. The responsible party shall keep records of
these inspections available for review by the City. Additional inspections
may be required after severe seasonal storms. See also the Stormwater
Management Maintenance section attached.
Routine maintenance of the site will include mowing, care of landscaping and
the removal of trash and debris from the drainage system. The parking lots
and driveways should be kept'clean and in repair. Events such as major storms
or heavy winds will require immediate inspections for damages.
To ensure proper water quality treatment, the water quality vault by
Stormwater Management will be inspected per manufacturer recommendations by
0 the manufacturer (see attached Section 2) or as directed by the City cf
Auburn.
Be careful to avoid introducing fertilizer to receiving waters or groundwater.
GO Catch Basins shall be cleaned when sump is 2/3, full of sediment or debris.
Storm Water Easement and Maintenance Agreement 3
Page 8 of 30
INSPECTION / MAINTENANCE CHECKLIST
II STRUCTURE
Results/
Maintenance
Date
Comments
ALL CATCH
Inspection
BASINS
Results
Maintenance
Done
FLOW CONTROL
Inspection
STRUCTURE
Results
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Maintenance
Done
Maintenance
Done
DETENTION PIPE/
Inspection
VAULT
Results
Maintenance
Done
FLOW CONTROL
Inspection
STRUCTURE
Results
Maintenance
Done
STORMWATER
MANAGEMENT'S
Inspection
WATER QUALITY
Results
,
VAULT AND
FILTER MEDIUM
Storm Water Easement and Maintenance Agreement
Page 9 of 30
Product Support
STORMWATgEt'm
MANAGEMENT
2035 N.E. Columbia Blvd.
Portland, Oregon 97211
0 Phone (503) 240-3393 Fax: (503) 240-9553
1-800-548-4667
http://Nv~lvw.stormwatermat.com
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Storm Water Easement and Maintenance Agreement
Page 10 of 30
SECTION I
INTRODUCTION TO CSF° STOFIVIWATER TREATMENT SYSTEMS
1.1 DESCRIPTION
The CSF® Stormwater Treatment System is offered in three different configurations: the Open Filter, the
Drop-In Filter, and the Linear Filter. Each uses Radial Flow Filter Cartridges housed in standard size pre-cast
concrete vaults (see Figure 1, Drop-In Filter) to produce a self-contained stormwater filtering system. The
filter systems are installed in-line with storm drains. The filter works by passing stormwater through the Radial
Flow Filter Cartridges containing CSF` filter media. The filter media traps particulates and adsorbs materials
such as dissolved metals and hydrocarbons. Floating surface scums and insoluble oil and grease are also
removed. After passing through the filter media, the stormwater flows into a collection pipe or discharges to an
open channel drainage way.
1.2 OPERATION
1.2.1 Purpose
The CSF® is a system designed to improve the quality cf stormwater runoff from the urban environment before
it enters receiving waterways. It is intended to function as a BNIP (Best ianagement Practice) to meet local,
state, and federal requirements which have been developed to comply with the Clean Water Act.
Through independent third party studies, it has been demonstrated that CSF® filters are highly effective for
treatment of first flush flows and flow paced flows during the latter part of a storm. In general, the CSFZ's
of iciency is highest when pollutant concentrations are highest. The primary target pollutants for removal are:
Sediments (TSS), Soluble Metals, and Oil & Grease.
1.2 .2 Sizing
CSF'Z filters are sized to treat the peak flow of a water quality design storm, as it passes through the filter. The
peak flow is determined by calculations based on the contributing watershed hydrology and using a design
storm magnitude. The design storm is usually based on the regulatory requirements set by the local stormwater
management agency. The particular size of a CSFS unit is determined by the number of Radial Flow Filter
Cartridges (see Figure 2) required to treat the peak stormwater flow. Each cartridge is designed to treat a peak
flow of 15 gpm. For example: a peak design stormwater flow rate of 150 gpm would require that 10 cartridges
be used in the treatment vault.
Because of the highly porous nature of the granular filter media, the flow through a newly installed cartridge is
restricted to 15 gpm, using a valve, to ensure adequate pollutant-media contact time.
Storm Water Easement and Maintenance Agreement
Page 11 of 30
PIEC+Sr cawci c VAULT ,ACCESS OOORS
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MANAGEMENT II ~I I
C'sF'OROP-IS FILTER
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Figure 1.
1.2.3 Basic Function
The CSF® unit is designed to allow stormwater runoff to percolate horizontally through a radial flow filter
cartridge containing filter media. The granular compost filter media acts as a mechanical filter to remove
sediments and as an ion exchanger to remove dissolved heavy metals. The media also acts as an adsorber to
remove Oils and Greases.
Priming System Function
The treated stormwater collects in the center tube of the cartridge which is equipped with a self priming siphon
system. This system, illustrated by Figure'2, consists of a "ball valve" located at the base of the cartridge and
a float located at the top of the cartridge. Initially the ball rests in a seat effectively closing off the port to the
drainage manifold. As a result, the filter fills the center drainage tube until the water level has risen high
enough to purge the air from the filter cartridges and displaces the float. At a water depth of 22 inches the float
pulls loose the ball and allows the filtered water to drain out through the manifold. This effectively "primes" a
siphon within the drainage tube and greatly increases the potential across the filter. The priming system
increases the durability (ability to be loaded with sediment) of the CSF®. A related feature is the CSF®
"hood". This hood maintains the siphon effect by preventing air from being drawn into the cartridge until the
external water level drops below the bottom lip.
Storm Water Easement and Maintenance Agreement
Page 12 of 30
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Figure 2. Individual Radial Flow Filter Cartridge
Radial Flow Cartridge Filter & Priming System Diagram
Air Relief Valet
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The CSF® Drop-In unit is designed with an overflow. The overflow operates when the inflow rate is greater
than the infiltration capacity of the filter media. Early in the rainy season sediment loading will have only a
small affect on the infiltration rate of the filter media. As the season progresses, sediment will build up on the
vault floor and on the filter surface. Build-up of sediment will cause the infiltration rate to gradually slow. As
the operating season continues to progress, sediment accumulation will continue to cause the infiltration
capacity to decrease. At some point it may be necessary to perform orifice adjustment maintenance, which.
involves further opening of the flow control valves.
The CSF® is also equipped with scum baffles that trap floating debris and surface films, even during overflow
conditions. Depending on individual site characteristics, some filters are equipped with high and/or low flow
bypasses. High flow bypasses are installed when the calculated peak storm event generates a flow which
overcomes the overflow capacity of the filter. This is especially important for the Drop-In filters. Low flow
bypasses are sometimes installed to bypass continuous inflows caused by ground water seepage, which usually
do not require treatment.
Storm Water Easement and Maintenance Agreement
Page 13 of 30
1.2.4 Maintenance Overview
The primary purpose of the CSF® is to filter out and prevent pollutants from entering our water ways. Like
any effective filtration system, periodically these pollutants must be removed to restore the CSF® to its full
efficiency and effectiveness. Maintenance requirements and frequency are dependent on the pollutant load
characteristics of each site. To assist the owner with maintenance issues, Stormwater Management provides
detailed Operation & Maintenance Guidelines with each unit.
Maintenance services can be provided completely, or in part, by Stormwater Management. We provide
tracking of all installed systems, notify the system's owner of maintenance needs, and notify the regulatory
agency that the system has been maintained.
0 Maintenance is usually performed late in the dry season to rejuvenate the filter media and prepare the system
for the next rainy season. Maintenance activities can also be required in the event of a chemical spill or
excessive sediment loading due to site erosion or extreme storms. It is also good practice to inspect the system
after severe storm events.
0
GO Media residuals can be re-composted to reduce residual hydrocarbons and then used in landscaping, erosion
control applications or daily cover for landfills. This sustainable process helps minimize total maintenance
costs.
Storm Water Easement and Maintenance Agreement
Page 14 of 30
SECTION 2
RECOMMENDED MAINTENANCE AND EXPECTED PERFORMANCE
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2.1 TYPES OF MALNTENANNCE
Presently, procedures have been developed for two levels of maintenance: 1. Inspection/minor maintenance
and, 2. Major maintenance. Inspection/minor maintenance activities are combined since the minor
maintenance does not require special equipment and typically little or no materials must be disposed of.
Inspection/minor maintenance typically involves opening the flow restricting valves (to pre-set levels) and
clean up of vegetation and debris. Major maintenance includes back flushing or cartridge replacement. Major
maintenance may involve disposal of materials which require consideration of regulatory guidelines. In
addition, depending on the particular unit configuration and equipment used, major maintenance may re uire an
understanding of OSHA rules. Table 1 summarizes the primary activities associated with CSF'V filter
maintenance.
Table 1: CSF Stormwater Treatment System Maintenance
Facility Component
Maintenance
When Maintenance Activity
Expected Facility Performance
Requiring Maintenance
Activity
Is Required
After Maintaining
CSF" Filter Cartridges and
Trash and Debris Removal
Floatable objects or other
Permantnt removal from storm
Containment Structure
trash is present in the filter. Remove to
system.
avoid hindrance of filtration and
eliminate unsightly debris and trash.
Vegetation Removal
Weeds or other vegetation is growing
Remove weeds and other vegetation
from the sides of the cartridges.
to avoid interference with infiltration.
Cartridge Back Flushing and
Media infiltration capacity is decreased
Restore infiltration capacity of the
Associated Sediment
I
due to normal sediment loading.
cartridges.
Removal
Cartridge Replacement and
1. :Media has been contaminated by high
1. New media is able to effectively
Sediment Removal
levels of pollutants, such as after a spill.
treat storniwater.
2. Compost infiltration capacity is
unrecoverable by back flushing due to
2. Restore the infiltration capacity of
excessive sediment loading.
the cartridges.
Drainage System Piping
I I Flushin, With Water
Drainage system is obstructed by debris
Outflow is not restricted.
or sediment.
Preceding Sediment
Trash and Debris Removal
Evidence of trash or floating debris in
Trash and debris removed: aesthetics
Trapping Devices (Ponds,
water.
improved, potential pollution source
Swales, Sedimentation
removed.
Nlanholes, etc.)
Sediment Removal
Reduced storage depth due to sediment
Sediment is removed to design depth:
(excavation, dredging,
accumulation.
forebay or manhole regains sediment
vacuuming)
trapping efficiency.
Storm Water Easement and Maintenance Agreement
Page 15 of 30
2? NL LkLNTENL A1NCE ACTIVITIES
2 .2.1 Maintenance Activity Timing
Three scheduled inspections/maintenance activities should take place during the year. One of these dates are
for minor maintenance activities (routine inspection, debris removal, further opening of the flow restricting
valve). The second date is to determine the type of major maintenance required and, if required for disposal,
obtain samples of the sediments and compost. It is often possible to determine what type of maintenance will
be required during the valve adjustment visit. In this case, the second visit may be omitted unless samples of
the filter media and sediment are required for analysis. The third scheduled date is to perfonn major
maintenance activities (back flushing or replacement of the compost cartridges and associated sediment
removal). In addition to the scheduled activities, it is important to check the condition of the filter after major
storms to check for damage caused by high flows and to check for high sediment accumulation which may be
caused by localized erosion in the drainage area. It may be necessary to adjust maintenance activity scheduling
depending on the actual operating conditions encountered by the filter system.
In general, the minor maintenance activities will occur during the rainy season, the maintenance inspection
will occur in early to mid summer, and the major maintenance work will occur in late summer to early fall
when flows into the filter are not likely to be present.
The months indicated in Table 2 show the best recommended times of year for maintenance activities to occur
in the Pacific Northwest.
Table 2: WORT: CALENDAR FOR NVESTERN OREGON ANM WASHDGTON
NVET
VET
DRY
VET
J.ki
FEB
NIAR
APR
bL-kY
JLIi
JUL
AUG
SEP
OCT
NOV
DEC
X I
I
XX
XX I
XXX
XXX
X = Schedule Observation And Minor Maintenance.
XX =Schedule Maintenance Inspection and media sampling during one of these months.
k3~= Schedule Major Maintenance during one of these months.
2 .2.2 Maintenance Activity Frequency
The primary factor controlling timing of maintenance for CSFS filter is sedimentation. A properly
functioning filter will remove solids from water by trapping these particulates within the porous structure of the
media. The flow through the filter will naturally decrease as more and more solids are trapped. Eventually the
flow through a filter will be low enough to require maintenance. At this time either the media is back flushed
(purge sediment by reversing flow direction) or the cartridges are replaced. Sediment should be removed from
upstream trapping devices on an as needed basis to prevent material from being re-suspended and discharged to
the filter.
Site conditions greatly. influence maintenance requirements. CSF® filters located in areas with erosion or
active construction should be inspected and maintained more often than those in fully-stabilized areas with
lisle erosion. The maintenance frequency may be adjusted as additional monitoring information becomes
available during the inspection program. Areas which develop known problems should be inspected more
Storm Water Easement and Maintenance Agreement
Page 16 of 30
frequently than other areas which demonstrate no problems, particularly, after large storms. Ultimately,
inspection and maintenance activities should be scheduled based on the historic records and characteristics of
an individual filter. It is recommended that the maintenance agency develop a database to property manage
compost filter maintenance programs.
Prior to the development of the maintenance database, the maintenance frequencies shown in Table 3 should be
followed. Frequencies should be updated as required. The recommended initial frequency for inspection/minor
maintenance is rwo times per year for the drop-in unit. Drop-In units should be inspected after all major
storms. Sediment removal on an annual basis is recommended until further knowledge is gained about a
particular filter.
Table 3: FREQUENCY OF ivLkENTENANCE ACTIVITY
L~
T
Cn
LYSPECTION/N11,'OR
N11kINTENANCE (TLNIES/YMAR)
itiL~JOR itiLaINTENANCE
(TINIES/YEAR)
Drop-In Units
1 (and after major storms)
1 (except in the case of a spill) i
2.3 'LvLk D, iTEi~iANCE CREW REQU NL fENTS
Table 4 lists the anticipated crew requirements for filter maintenance operations. The removal of back flush
water and sediments during major maintenance activities can be accomplished using either a pump and water
truck or a vacuum truck:. All applicable safer' (OSI-L;,) and disposal regulations should be followed. A general
description of the maintenance activities follows.
Table t: ANTICIPATED CREW REQUIREMENTS
Drop-In Units
Inspection/tifinor
ivlaintenance I
Nlajor Maintenance:
Baca Flush
Major Maintenance:
Cartridge Replacement
Laborer
~
.
Utility Worker
I
1
1
Senior Sewer Operator
Vacuum/Water Truck Operator
1
1
Hauling Truck Operator
Total
I 1*
2*
3~
Special Requirements
Knowledge of Proper
Valve Positioning
Knowledge of Back
Flush Procedures
Knowledge of
Cartridge Removal
and Installation
Procedures
* ivlay require OSHA trained person if vault entry occur.
Storm Water Easement and Maintenance Agreement
Page 17 of 30
2.4 N INTEYAINCE METHODS
2.4.1 Minor ivlaintenanceNalve Adjustment Method (Once A Year)
Minor maintenance typically will involve the steps below, however if it appears that a spill of some type has
occurred, the local hazard control agency and Stormwater Management should be notified immediately. In the
case of a spill, the worker should abort maintenance activities until the proper guidance has been
obtained.
Steos for Minor Maintenance
1. Maintenance to be performed by a utility worker familiar with CSF'V units.
2. If applicable, set up safety equipment up to protect pedestrians from fall hazards presented by
open doors. Also set up appropriate safety equipment for work near roadways.
3. Inspect the external condition of the unit and take notes concerning defects/problems.
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4. Open the doors to the vault and allow the filter to air out for 5-10 minutes.
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5. Without entering the vault, inspect the inside of the unit, including components.
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6. Take notes about the external and internal condition.
7. Give particular attention to recording the level of sediment build-up on the floor of the vault in the for.-bay,
and on top of the internal components. If flow is occurring, note the level of water and estimate the flow
rate per drainage pipe. Record all observations.
8. Remove large loose debris and trash should be removed using a pole with a grapple or net on the end.
9. Locate the flow restricting slide gate valves.
10. Open the valves further by pulling upward on the handle of the slide gate using a pole with a ring on the
boom end. Open the valve fully on the mid-season visit.
11. If flow is occurring, note the relative increase due to opening the valve.
12. Close and fasten the door, and remove safety equipment.
13. Finally, make notes about the local drainage area relative to ongoing construction, erosion problems, or
high loadings of other materials to the filter.
Storm Water Easement and Maintenance Agreement
Page 18 of 30
2.4.2 Major Maintenance Inspection (Once A Year)
The primary goal of the major maintenance inspection is to assess the condition of the cartridges relative to the
level of sediment loading. It may be desirable to conduct this inspection during a storm to observe the relative
flow through the compost cartridges. If the submerged cartridges are severely plugged, large amounts of
sediments should be present, very little flow will be discharging from the drainage pipes, and. it is likely that the
cartridges need to be replaced. If the submerged cartridges are only partially plugged, significant flow will still
be discharging from the drainage pipes, only low levels of sediment will be present, and back flushing may be
the appropriate major maintenance type. Major maintenance inspection will typically involve the steps below.
However, if it appears that a spill of some type has occurred, the local hazard control agency and Stormwater
Management should be notified immediately. In the case of a spill, the worker should abort maintenance
activities until the proper;uidance has been obtained.
Steps For Pre-Major Maintenance Inspection
1. Maintenance to be performed by a utility worker familiar with CSF® units.
2. If applicable, set up safety equipment to protect pedestrians from fall hazards presented by open doors.
Also, set up appropriate safety equipment for work near roadways.
3. Inspect the external condition of the unit and take notes concerning defects/problems.
4. Open the doors to the vault and allow the vault to air out for 5-10 minutes.
® S. Without entering the vault, give the inside of the unit, including components, a general condition
11 inspection.
® 6. Take notes about the external and internal condition.
7. Give particular attention to recording the level of sediment build-up on the floor of the vault, in the forebay,
and on top of the internal components.
8. Remove large loose debris and trash using a pole with a grapple or net on the end.
9. If the visit is during a storm, make the flow observations discussed above.
10. Close and fasten the door, and remove safety equipment.
11. Make notes about the local drainage area relative to ongoing construction, erosion problems, or high
loadings of other materials to the filter.
12. Review the condition reports from the previous minor maintenance visit. Review the current condition and
determine the appropriate type of major maintenance. If no flow observations have been made, use the
following criteria: back flush the units if there is less than 1 inch of fine sediment (not coarse debris such
as bark mulch) build-up on the floor of the vault; replace the cartridges if there is more than 1 inch of fine
sediment build-up.
Storm Water Easement and Maintenance Agreement
Page 19 of 30
2.4.3 Major MiaintenanceBack Flushing Method
Major maintenance/back flushing typically will involve the steps below. However, if it appears that a spill of
some type has occurred, the local hazard control agency and Stormwater iVlanagement should be notified
immediately. In the case of a spill, the worker should abort maintenance activities until the proper
guidance has been obtained. Depending on the configuration of the particular filter, a worker may be required
to enter the vault to perform some tasks. If vault entry is required, OSHA rules for general confined space
entry must be followed. Back flushing should occur during dry weather and it may be necessary to plug the
filter inlet pipe if base flows exist.
Depending on the nature of the sediments accumulated on the surface of the filter, back flushing may or
may not be an option. In cases where the sediment is sticky and plastic, back flushing may not be
effective. If these conditions exist, please call our maintenance department at 1-800-548-4667 for
assistance.
Steps For Back Flushing Maintenance
1. A utility worker and water (or vacuum) truck operator are required to perform this maintenance. The
vehicle used to back flush the filters must be equipped with a device to deliver a clean water flow of 15
e~ apm to each cartridge being flushed. In addition, the proper flush water hose to cartridge connectors must
be used. Information concerning the connection method is available from Stormwater ivlanagement.
2. If applicable, set up safety equipment to protect pedestrians from fall hazards presented by open door.
X Also, set up appropriate safety equipment for work near roadways.
3. Inspect the external condition of the unit and take notes concerning defects/problems.
4. Open the doors to the vault and allow the filter to air out for 5-10 minutes.
5. Without entering the vault, give the inside of the filter a general condition inspection. The atmospheric
quality is tested using a properly calibrated device. Note: Do not perform vault entry if acceptable
atmospheric quality cannot be attained. Use 05FLA. equipment and guidelines.
6. Ni lake notes about the extern al and internal condition.
7. Give particular attention to recording the level of sediment build-up on the floor of the vault, in the forebay,
and on top ofthe internal components.
8. Remove large loose debris and trash using a pole with a grapple or net on the end.
9. Hose off or vacuum the outside of each basket with a low pressure spray or vacuum
10. The worker should remove the 4" top cap from the back flush tube. This tube is centered at the top of each
cartridge (see Figure 3, Cartridge).
11. Attach the back flush hose to the too of the back flush tube.
12. Slowly fill the central drainage tube such that the ball valve does not become unseated. Bring the flow
rate to a level between 15 and 20 gpm. Apply a flow of approximately for a duration of 3 to 5 minutes. It is
important that the amount of water in the truck be sufficient to hose off and flush the required number of
Storm Water Easement and Maintenance Agreement
Page 20 of 30
cartridges, otherwise additional refill trips will be required. (Stormwater Management utilizes a recirculating
system and removes the sediment from the backflush water with a portable filter.)
13. Repeat steps 9 through 12 for all cartridges.
14. Inspect the float mechanism to insure it travels freely in the center drainage tube. If needed, apply a light
film of silicon lubricant to the cap. Screw the cap be on insuring a water tight seal. Inspect the air relief valve
to insure it operates.
15. Pump (or vacuum) the flush water and sediments from the vault back into the truck reservoir.
16. Locate the flow restricting slide gate valves.
=17 Reser the opening of-the valves to the lowest level by pushing downward on the handle of the slide gate
using a pole with a ring on the bottom end. The lowest level setting will have been preset using a restraining
collar on the valve shaft. The valve opening corresponding to this setting is determined by the number of
cartridges on the drainage line. The valve opening is set to allow a flow of 15 gpm/cartridge for freshlv
charged or back flushed cartridges.
13. Close-and flsten the door, and remove safety equipment
19 Make notes about the local drainage area relative to ongoing construction, erosion problems, or high
C'7 loadings of other materials to the filter.
\OTE: An alternate method to back flushing is to completely remove the float assembly and plugging the 2"
discharge port with an inflatable plug. This plug must be able to fit inside a 2 inch d'i'ameter schedule 40 PVC
pipe until inflated and is used to prevent the flush water from exiting through the outlet rather than passing
through the media. The valve stem of the inflatable plug should be rigid and long enough to protrude
approximately 2 inches above the top of the back flush port when inflated. All other operations remain the
same.
Storm Water Easement and Maintenance Agreement
Page 21 of 30
Figure 3. Individual Radial Flow Filter Cartridge
Radial Flow Cartridge Filter & Priming System Diagram - Post Flow
Air Relief Valve
Threaded Cap
Float
V
~l J
C
Water Flos
Direction
y
A~. X31
r
Filter lIedta
:i
r
Filter iVledia
o _
Y
t
-I i
Concrete Floor
2.4.4 Major maintenance/Cartridge Replacement
2 in. Connection Nipple
Drainage Manifold Pipe
L
Major maintenance/filter cartridge replacement typically involve the steps below. However, if it appears that a
spill of some type has occurred, the local hazard control agency and Stormwater Management should be
notified immediately. In the case of a spill, the worker should abort maintenance activities until the
proper guidance has been obtained. Depending on the configuration of the particular filter, a worker may be
required to enter the vault to perform some tasks. If vault entry is required, OSHA rules for general confined
space entry must be followed. Filter cartridge replacement should occur during dry weather and it may be
necessary to plug the filter inlet pipe if base flows exist. There should be no standing water present in the vault
during this operation.
Hood
Filter Surface
Inner Drainage Tube
Buoyant Ball
Ball Seat
Flow Control Valve
Storm Water Easement and Maintenance Agreement
Page 22 of 30
1. Depending on the particular unit, one or two utility workers and a hauling truck operator will deliver the
replacement cartridges to the location of the filter. Information concerning how to obtain the replacement
cartridges is available from Stormwater Management. Arrangements should be made in advance for a
vacuum truck- to clean out sediment prior to placing the new cartridges into the system.
2. If applicable, set up safety equipment to protect pedestrians from fall hazards presented by open door.
Also, set up appropriate safety equipment for work near roadways.
3. Inspect the external condition of the unit and take notes concerning defects/problems.
4. Open the doors to the vault and allow the filter to air out for 5-10 minutes.
5. Without entering the vault, give the inside of the unit, including components, a general condition
inspection.
6. Make notes about the external and internal condition.
7. Give particular attention to recording the level of sediment build-up on the floor of the vault, in the forebay,
and on top of the internal components.
8. Remove large loose debris and trash using a pole with a grapple or net on the end.
t~ 9. Using a boom, crane, or other device (dolly and ramp), off load the replacement cartridges (150 lbs each)
0 and set aside.
10. Using an appropriate sling, attach the cable from the boom, crane, or tripod to the cartridge being removed.
O This, activity may require that worker enter the vault to remove the cartridges: from the drainage system
and place them under the vault opening for lifting. Take care not to damage the drainage system
connecting PVC nipple. This nipple should remain installed in the drainage pipes (See diagram).
11. Remove the cartridge (250 ibs each) from the vault. Care must be used to avoid damaging the cartridges .
during removal and installation. The cost of repairing components damaged during maintenance will
be the responsibility of the owner unless the operation is being performed by Stormwater
Management and the damage is not related to discharges to the system.
12. Set the used cartridge aside or load onto the hauling truck.
13. Continue steps 10 through 12 until all cartridges have been removed.
14. Using a vacuum truck, remove deposited sediment from the floor of the vault and, if large amounts are
present, from the forebay. A vacuum truck may not be necessary if the sediment is relatively dry and the
unit is small. It may be possible to shovel the sediment into containers which, once full, are lifted
mechanically from the vault and placed onto the hauling truck.
15. Once the sediments are removed from the vault, it is necessary to assess the condition of the cartridge-
drainage system connection nipples. These are short sections of 2 inch schedule 40 PVC which should
protrude above the floor of the vault. If required, apply a light coating of FDA approved silicon grease to
the outside of the exposed portion of the nipples. This ensures a water tight connection between the
cartridge and the drainage pipe. Replace any damaged nipples.
Storm Water Easement and Maintenance Agreement
Page 23 of 30
16. Using the boom, crane, or tripod, lower and install the new cartridges. Once again, take care not to damage
connections.
17. Locate the flow restricting slide gate valves.
18. Reset the opening of the valves to the lowest level by pushing downward on the handle of the slide gate
using a pole with a ring on the bottom end. The lowest level setting will have been preset using a
restraining collar on the valve shaft. The valve opening corresponding to this setting is determined by the
number of cartridges on the drainage line. The valve opening is set to allow a flow of 15 gpm/cartridge for
freshly charged or back flushed filters.
19. Close and fasten the door, and remove safety equipment
20. Make notes about the local drainage area relative to ongoing construction, erosion problems, or high
loadings of other materials to the filter.
Q 21. Finally, dispose of the residual materials in accordance with applicable regulations. Make arrangements to
return the used cartridges to Stormwater Management.
O 2.4.5 Related Maintenance Activities (Performed On An As Needed Basis)
CSF® units are often just one of many components in a more comprehensive stormwater drainage and
treatment system. The entire system may include catch basins, detention vaults, sedimentation vaults and
manholes, detention/retention ponds, swales, artificial wetlands, and other miscellaneous components. In order
for maintenance of the CSF unit to be successful, it is imperative that all other components be properly
maintained. The maintenance/repair of upstream facilities should be carried out prior to the CSF® maintenance
activities. In addition to considering upstream facilities, it is also important to correct any problems identified
in the drainage area. Drainage area concems may include: erosion problems, heavy oil & grease loading, and
discharges of inappropriate materials.
Storm Water Easement and Maintenance Agreement
Page 24 of 30
2.5 TYPICAL EQUIPMENT REQUIRED FOR ivLkEI TEYAIr'CE ACTIVITIES
Typical equipment required for conducting maintenance is shown in Table 5. Some of the materials listed are
suggestions rather than requirements. It should be noted that there is more than one way to accomplish some
tasks. Owners with available labor and equipment resources may desire to use alternative methods. However,
it is advisable that guidance from Stormwater Management be obtained prior to using alternative techniques.
Questions about proper equipment should be directed to Stormwater ivianagement.
Table 5: i1LkLNTENANCE EQUIPMENT REQUIRENIENTS
C~
11
V4
in
0
X
0)
Maintenance Equipment Required
Minor Maintenance
Valve Adjustment
Pre-Nlajor Maintenance
Inspection -
Major Maintenance Back
- Flushing
Major Maintenance
Cartridge Replacement
Safety Equipment*. first-
aid, cones, barricades,
r1ain, flares, tape,
vests, hard hats.
=Safety Equipment*: first
aid, cones, barricades,
flagging, flares, tape,
vests, hard hats.
Safety Equipment*: first
aid, cones, barricades,
flagging, flares, tape,
vests, hard hats.
Safety Equipment*: first
aid, cones, barricades,
flagging, flares, tape,
vests, hard hats.
Work Clothes: rubber
boots, coveralls, gloves.
Work Clothes: rubber
boots, coveralls, gloves.
Work Clothes: rubber
boots, coveralls, gloves.
Work Clothes: rubber
boots, coveralls, gloves.
Door Balt. "Wrench,
Pentasocket And
Miscellaneous Tools.
Door Bolt, Wrench,
Pentasocket And
Miscellaneous Tools.
Door Bolt, Wrench,
Pentasocket And
Miscellaneous Tools.
Door Bolt, Wrench,
Pentasocket And
Miscellaneous Tools.
Tape Measure
Tape Measure
Tape Measure
Tape Measure
Flashlight
Flashlight
Flashlight
Flashlight
Grapple or Net Pole
Grapple or Net Pole
Grapple or Net Pole
Grapple or Net Pole
Valve Adjustment Pole (
Record Keeping Forms
Valve Adjustment Pole
Valve Adjustment Pole
Record Keeping Forms
Trash/Debris Container
Record Keeping Forms
Record Keeping Forms
Trash/Debris Container
Water/Vacuum Truck
Vacuum Truck
Back Flush Connections
Replacement Cartridges
Back Flush Flow Control
Cartridge Hauling Truck
Spray Nozzle
Lifting Device (300 lb)
Cartridge Outlet Plugs
Shovels
Vault Inlet Pipe Plug
Extra 2 Inch PVC Caps
Back Flush Timer
Trash/Debris Container
Silicon Valve Grease
Vault Inlet Pipe Plug
Trash/Debris Container
Dolly
Ladder
PVC Pipe Cutter
Ladder
Cartridge Installation
And Removal Sling
10 Feet of Extra 2 Inch
PVC Pipe
'Confined space equipment may be required for vault entry. This equipment must be used by personnel with the appropriate
OSHA training. This equipment typically includes: atmospheric testing devices, atmospheric purging aad ventilating devices,
and entry, exit, and rescue assisting devices.
Storm Water Easement and Maintenance Agreement
Page 25 of 30
C?'
0
GO
2.6 MATERIAL DISPOSAL
The accumulated sediment found in stormwater treatment and conveyance systems must be handled and
disposed of in a manner which will not allow the material to affect surface or ground water. It is possible for
sediments to contain measurable concentrations of heavy metals and organic chemicals (such as pesticides and
petroleum products). Areas with the greatest potential for high pollutant loading include industrial areas and
heavily traveled arterials. Sediments and flush waters must be disposed of in accordance with all applicable
waste disposal regulations. It is not appropriate to discharge these materials back to the stormwater drainage
system. Part of arranging for maintenance to occur should include coordination of disposal of solids (landfill
coordination) and liquids (municipal vacuum truck decant facility, local wastewater treatment plant, on-site
treatment and discharge). Owners should contact the local public works department and inquire about how the
department disposes of their street waste residuals.
Disposal methods or reuse of the compost contained in the cartridges will be determined by Stormwater
Management. If the material has been contaminated with any unusual substance, the cost of special handling
and disposal will be the responsibility of the owner.
Storm Water Easement and Maintenance Agreement
Page 26 of 30
r
~
Sample CSF® Minor Maintenance And Inspection Data Sheet
Date: Location:
Filter Size: TYPE: Open Drop-In Personnel:
Filter Observations
Compost Months in Service:
Oil and Grease in Forebay:
Sediment Depth in Forebay:
Sediment Depth on Vault Floor:
Structural Damage:
Estimated Flow From Drainace Pipes (if available):
Cartridges Submerged (Yes No
How Deep:
0
qa CSFJ Minor Maintenance Activities (check off if done and ;ive description)
0
® Remove Trash and Debris:
Valve Adjustment (to full open):
Minor Structural Repairs:
Drainage Area Report
Excessive Oil and Grease Loading (Yes NoSource:
Sediment Accumulation on Pavement (Yes No__) Source:
Erosion of Landscaped Areas (Yes No,)So urce:
Items Needing Further Work:
Comments:
Storm Water Easement and Maintenance Agreement
Page 27 of 30
CD
0
F"
C
GO
Sample CSr Major Maintenance Inspection Data Sheet
It may be desirable to conduct this inspection during a storm to observe the relative flow through the CSFD
cartridges. If the submerged cartridges are severely plugged, large amounts of sediments should be present, very
little flow will be discharging from the drainage pipes, and it is likely that the cartridges need to be replaced during
major maintenance. If the submerged cartridges are only partially plugged, significant flow will still be discharging
from the drainage pipes, only low levels of sediment will be present, and back flushing may be the appropriate
major maintenance type.
Date: Location:
Filter Size:
Filter Observations
Compost Months in Service:
Oil and Grease in Forebay:
Sediment Depth in Forebay:_
Sediment Depth on Vault Floor:
Structural Damage:
Estimated Flow From Drainage Pipes (if available):
Cartridges Submerged? (Yes No__) How Deep?
Drainage Area Report
Excessive Oil and Grease Loading (Yes Noi) Source: _
Sediment Accumulation on Pavement (Yes No ) Source:
Erosion of Landscaped Areas (Yes No_) Source:
Comments:
Review the condition reports from the previous minor maintenance visits. Review the current condition and
determine the appropriate type of major maintenance. If no flow observations have been made, use the following
criteria: back flush the units if there is less than about 1 inch of fine sediment (not coarse debris such as bark
mulch) build-up on the floor of the vault; replace the cartridges if there is more than about I inch of fine sediment
build-up.
Storm Water Easement and Maintenance Agreement
Page 28 of 30
TYPE: Open Drop-In . Personnel: