HomeMy WebLinkAboutITEM III-A11 1 0~
Memorandum
~~x~~~~
T0: Planning Commission
FROM: Chris Andersen, Interim Environmental Protection Manager, and Jennifer Shih,
Environmental Planner
CC: Pete Lewis, Mayor
Kevin Snyder, Interim Director, Planning and Development Department
Jeff Dixon, Principal Planner
Elizabeth Chamberlain, Principal Planner
Dennis Dowdy, Director, Public Works Department
Dennis Selle, City EngineerlAssistant Public Works Director
Ingrid Gaub, Assistant City Engineer Tim Carlaw, Storm Drainage Engineer
Dan Heid, City Attorney
Steve Gross, Assistant City Attorney
DATE: March 17, 2010
SUBJECT: Special Meeting -Work Session to discuss recommended revisions to proposed
amendments to floodplain development regulations
The March 23, 2010 Special Planning Commission meeting will be a work session to review the
recommended revisions to the proposed floodplain development regulation amendments as a result of a
revised FEMA model ordinance and comments from FEMA staff on the City's proposed amendments.
Back r.~ ound
On March 1, 2010, the Public Works Committee reviewed and discussed the proposed amendments
previously reviewed by the Planning Commission at a regular meeting of the Committee.
On March 8, 2010, the Planning and Community Development Committee reviewed the proposed
amendments previously reviewed by the Planning Commission and approved forwarding Ordinance No. 6295
to the full City Council for adoption.
On March 9, 2010, the Federal Emergency Management Agency issued a model ordinance relating to
floodplain management and the Endangered Species Act and associated regional guidance documents for public review, with a public comment period of March 9, 2010 to April 5, 2010. The
revised FEMA regional
guidance addressing habitat mitigation and hydrologic and hydraulic studies are referenced in the proposed
amendments, copies of which are included as Attachments #3 and #4.
On March 11, 2010, the staff Floodplain Review Committee reviewed the changes between the new version
of the model ordinance and the previous version used to develop proposed amendments to the City of Auburn
floodplain regulations. Based on that review, staff is recommending modifications to the proposed
amendments of Ordinance No. 6295 to ensure that the City's amendments meet the Endangered Species Act
compliance requirements for the National Flood Insurance Program as transmitted by FEMA.
On March 15, the proposed amendments were returned to the Public Works Committee for review of the
proposed amendments including the additional revisions recommended by staff resulting from changes to the
FEMA model ordinance.
On March 16, FEMA staff provided the City with an initial set of review comments on the City's proposed
floodplain amendments. Ordinance No. 6295 has been revised to reflect the review comments received from
FEMA along with several minor edits for readability and clarity.
Please find attached the following for your review: ■ Agenda for March 23, 2010 Special Planning Commission Meeting
■ Attachment # 1-Revised Ordinance No. 6295
■ Attachment #2 -Draft Regulatory Floodplain Map
■ Attachment #3 -Revised Regional Guidance for Habitat Assessment
■ Attachment #4 -Revised Regional Guidance for Hydrology and Hydraulic Studies
For reference purposes, FEMA's revised model ordinance issued March 9, 2010 can be found at the following
location: http://www.ferna.gov/pdf/about/regions/regionx/draft_nfip_esa_ordinance.pdf .
Please call or e-mail if you have any questions about the packet materials.
Chris Andersen, Environmental Protection Manager
253-876-1962
cndersen@auburnwa. gov
Jennifer Shih, Environmental Planner
253-804-5092
jshih@auburnwa.gov
2
ORDINANCE N0.6_
AN ORDINANCE OF THE CITY COUNCIL OF THE CITY
OF AUBURN, WASHINGTON, RELATING TO
FLOODPLAIN MANAGEMENT REGULATIONS;
ADOPTING REGULATIONS INCORPORATING FEDERAL
HABITAT PROTECTION REQUIREMENTS INTO
EXISTING REGULATIONS, ESTABLISHING
REQUIREMENTS FOR A FLOODPLAIN DEVELOPMENT
PERMIT, UPDATING RELATED PROVISIONS OF LAW,
AND AMENDING CHAPTERS 14.03 AND 15.68, AN D
SECTIONS 16.10.010, 16.10.070, 17.04.300, 17.09.050,
AND 17.14.110 OF THE AUBURN CITY CODE, AND
CREATING NEW SECTIONS 17.04.305, 17.04.335 AND
18.70.025 OF THE AUBURN CITY CODE, AND
REPEALING SECTION 17.04.045 OF THE AUBURN CITY
CODE CONNECTED THEREWITH
WHEREAS, the City is required, as a condition of continued eligibility in the
National Flood Insurance Program (NFIP} to adopt floodplain management regulations
that meet the requirements of the federal flood plain management criteria for flood-
prone areas in the Code of Federal Regulations (44CFR 60.3} ;and
WHEREAS, the City currently regulates floodplain management by using a
combination of specific floodplain management regulations, critical area regulations,
shoreline management regulations, and State Environmental Policy Act (SEPA)
regulations; and
WHEREAS, in October, 2008, the City received notice from the Federal
Emergency Management Administration (FEMA) and the National Marine Fisheries
Service (NMFS) that those agencies had collaborated on a position paper that seeks to
prevent continued degradation of existing floodplain, and to promote low impact
development in floodplain areas of the region that could effect endangered species; and
Ordinance No. 6295
March 12, 2010 Page 1 of 44
WHEREAS, FEMA and NMFS took the position that if a permitting agency, such
as the City of Auburn, grants permits in floodplain areas within its boundaries that are
later determined to adversely affect ~ the floodplains andlor endangered species,
the permitting agency will be liable for the resulting "take" on endangered species; and
WHEREAS, in response to the position taken by the federal agencies, the City
imposed a moratorium on development in floodplains within the City, which moratorium
continues to be in effect; and
WHEREAS, FEMA, in consultation with NMFS, began working on a model
ordinance that, if substantively adopted by local jurisdictions, would allow those
jurisdictions to resume permitting development in the floodplain. The provisions of the
model ordinance are intended to help ensure that impacts on the floodplain and on
habitat were properly evaluated and, if necessary, mitigated; and
WHEREAS, the federal agencies invited several local jurisdictions, including
Auburn, to participate in a focus group during the development of this model ordinance;
and
WHEREAS, although federal agencies incorporated some of the suggestions
from the local jurisdictions, the substantive requirements that the local jurisdictions must
adopt are mandated by the federal agencies and are not subject to modification by the
local jurisdictions.
WHEREAS, the federal agencies must approve the City's incorporation of the
substantive terms of the model ordinance; however, the provisions of model ordinance
provide sufficient guidance to allow the City to resume processing development permits
in the floodplain incompliance with the interim measure required by NMFS; and
Ordinance No. 6295
March 12, 2010 Page 2 of 44
WHEREAS, It is the Council's intention to adopt the below stated regulations as
interim regulations until such time as the federal agencies approve them as permanent
measures, at which time they shall become permanent regulations.
NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF AUBURN,
WASHINGTON, DO ORDAIN as follows:
Section 1. Amendment to City Code. Chapter 14.03 of the Auburn City
Code be and the same hereby is amended to read as follows:
Chapter 14.03
TYPES OF PROJECT PERMIT DECISIONS
Sections:
14.03.001 Generally.
14.03.010 Type I decisions.
14.03.020 Type II decisions.
14.03.030 Type III decisions.
14.03.040 Type IV decisions.
14.03.050 Type V decisions.
14.03.060 Legislative nonproject decisions.
14.03.001 Generally.
Project permit decisions are classified into five types, based on whether a
director, the hearing examiner or the city council makes the decision and the process by
which that decision is made. (Ord. 4835 § 1, 1996.)
14.03.010 Type I decisions.
Type I decisions are administrative decisions made by the city which are not
subject to environmental review under the State Environmental Policy Act (SEPA)
codified at Chapter 43.21 C RCW. Type I decisions include, but are not limited to, the
following project applications:
A. Building permit;
B. Plumbing permit;
C. Mechanical permit;
D. Utility permit;
E. Special permit;
F. Excavation permit;
G. Land clearing permit;
H. Grading permit;
I. Floodplain development vvi i~rv! ~~n° permit;
J. Public facility extension agreement;
Ordinance No. 6295
March 12, 2010 Page 3 of 44
K. Right-of-way use permit;
L. Lot line adjustment;
M. Home occupation permit;
N. Temporary use permit (administrative};
0. Administrative use permit;
P. Short subdivision (plat};
Q. Mobile home closure plans. (Ord. 5746 § 2, 2003; Ord. 4835 § 1, 1996.)
14.03.020 Type II decisions.
Type II decisions are administrative decisions made by the city which include
threshold determinations under SEPA. Type II decisions include, but are not limited to,
the following project applications:
A. Building permit;
B. Grading permit;
C. Land clearing permit;
D. Public facility extension agreement;
E. Administrative use permit;
F. Short subdivision (plat}.
G. Floodplain development permit._(Ord. 4835 § 1, 1996.)
14.03.030 Type III decisions.
Type III decisions are quasi-judicial final decisions made by the hearing examiner
following a recommendation by staff. Type III decisions include, but are not limited to,
the following project applications:
A. Temporary use permit;
B. Substantial shoreline development permit;
C. Variance;
D. Special exceptions;
E. Special home occupation permit;
F. Preliminary plat;
G. Conditional use permit;
H. Surface mining permit. (Ord. 6184 § 3, 2008; Ord. 4835 § 1, 1996.)
14.03.040 Type IV decisions.
Type IV decisions are quasi-judicial decisions made by the city council following
a recommendation by the hearing examiner. Type IV decisions include, but are not
limited to, the following project applications:
Rezone (site-specific). (Ord. 6184 § 4, 2008; Ord. 4835 § 1, 1996.}
14.03.050 Type V decisions.
Type V decisions are quasi-judicial decisions made by the city council following a
recommendation by staff. Type V decisions include, but are not limited to, the following
project applications:
Final plat. (Ord. 6184 § 5, 2008; Ord. 4835 § 1, 1996.)
Ordinance No. 6295
March 12, 2010 Page 4 of 44
14.03.060 Legislative nonproject decisions.
Legislative nonproject decisions made by the city council under its authority to
establish policies and regulations are not classified as a "type" of project permit
decision. Legislative nonproject decisions include, but are not limited to, the following
legislative actions:
A. Amendments to the text and map of the comprehensive plan or
development regulations.
B. Amendments to the zoning map (rezones) on a city-wide or area-wide
basis. (Ord. 4835 § 1, 1996.}
Section 2. Amendment to City Code. Chapter 15.68 of the Auburn City
Code be and the same hereby is amended to read as follows:
Chapter 15.68
FLOOD HAZARD AREAS
Sections:
Article I. Statutory Authorization, Findings of Fact, Purpose and Objectives
15.68.010 y ~ .Reserved.
15.68.020 ~i"ui""yv of fuel. ,Reserved.,
15.68.030 Statement of purpose.
15.68.040 Methods of reducing flood losses.
Article II. Definitions
15.68.050 Interpretation of language.
15.68.060 Definitions.
Article III. General Provisions
15.68.070 Land to which this chapter applies.
15.68.080 .Reserved.
15.68.090 Penalties for noncompliance.
15.68.100 Abrogation and greater restrictions.
15.68.110 Interpretation.
15.68.120 Warning and disclaimer of liability.
15.68.125, Appeals.
Article IV. Administration
1 Prior Legislation: Orris. 4214 and 4220.
Ordinance No. 6295
March 12, 2010 Page 5 of 44
15.68.130 Establishment of and re uirement to obtain flood lain development
permit.
15.68.135 Floodplain development permit application.
15.68.136 Floodplain develo ment ermit ex iration.
15.68.140 ~eNeu!e~. Designation of floodplain administrator.....
15.68.141 Duties of the floodplain administrator.
15.68.150 Duties and responsibilities of the vi±y eny;neer public works
department.
15.68.151 Duties and responsibilities of the •
planning and development department.
Article V. Provisions for Flood Hazard Protection
15.68.160-,°nor~l ~`~n~~r~v Standards of the ~;ty of A~;N~;;n ony~noo~iny
r~livi~inn ublic works de artment. u,v,~,~„
15.68.161 ~ Standards of the •
planning and development department.
15.68.170 Additional standards of the •
tannin and develo ment de artment.
15.68.180 Floodways and communit acknowled ement of FEMA ma
amendments.
15.68.190 Development within areas of special flood hazard.
15.68.200 Compensatory storage equipment.
Article I. cf,~„f~~„ n „~~~~;"f;~„~ Cinrlinn~► purpose
15.68.010 RESERVED u •n: Tho larriel~+i iro of +ho a+~+o of 1Ahehinn+nn hie in ~+~+a I~~ni rlalorr~+orl +ho
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15.68.020 RESERVED F;nu;""yam ~f fu~~.
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in~rlorvi i~+olv ~nnhnrorl rl~m~rro i i~o~ in n+hor ~ro~~ I I~o~ +h~+ pro in~rlorvi i~+ohi i~►uvM~.+uwi y Zvi vu, uu~ ~ ~uy~ uvv~ ~ vvw ~u< ~c.~uvM~.+c.«vi y
flnnrl In~~ ~nrrl R1 G;1 1 ~nnQ• (lrrl /I S~7n f: 1 1 QQ~• (lrrl /I'~~7 f: 7~1 7l 1 QS~Q 1 iivv~+ iv.w. Zvi v i v i ~ i , ~vvv, vi u. ~v~v ~ i , i vvv, vi ~vv i ~ i i vvv.~
Ordinance No. 6295
March 12, 2010 Page 6 of 44
15.68.030 Statement of purpose.
It is the purpose of this chapter to promote the public health, safety, and general
welfare, and to minimize public and private losses due to flood conditions in specific
areas by provisions designed:
A. To protect human life and health, and to protect property;
B. To minimize expenditure of public money and costly flood control projects;
C. To minimize the need for rescue and relief efforts associated with flooding
and generally undertaken at the expense of the general public;
D. To minimize prolonged business interruptions;
E. To minimize damage to public facilities and utilities such as water and gas
mains, electric, telephone and sewer lines, streets and bridges located in areas of
special flood hazard;
F. To help maintain a stable tax base by providing for the sound use and
development of areas of special flood hazard so as to minimize future flood blight areas;
G. To ensure that potential buyers are notified that property is in an area of
special flood hazard; and
H. To ensure that those who occupy the areas of special flood hazard
assume responsibility for their actions.
A. Minimize the need for publicly funded and hazardous rescue efforts to
save those who are isolated by flood waters;
B. Minimize expenditure of public money for costly flood damage repair and
flood control projects;
C. Minimize disruption of commerce and governmental services;
D. Minimize damage to public facilities and utilities such as water and gas
mains, electric, telephone and sewer lines, streets, and bridges located;
E. Maintain a stable tax base by providing for the sound use of floodprone
areas so as to minimize future flood blight areas;
F. Ensure that those who occupy areas subject to flooding and channel
migration assume responsibility fortheir actions;
G. Qualify the City of Auburn for participation in the National Flood Insurance
Pro ram, thereby giving citizens and businesses the opportunity to purchase flood
insurance;
H. Maintain the quality of water in rivers, streams, and lakes, and their
floodplains so as to protect public water supplies, areas of the Public Trust, and wildlife
habitat protected by the Endangered Species Act;
I. Retain the natural channel shoreline and flood lain creation rocesses
and other natural floodplain functions that protect, create, and maintain habitat for
threatened and endangered species.
J. Prevent or minimize loss of h draulic eomor hic and ecolo ical
functions of floodplains and stream channels. _(Ord. 6161 § 1, 2008; Ord. 4820 § 1,
1995; Ord. 4357 § 2(1.3), 1989.)
15.68.040 Methods of reducing flood losses.
In order to accomplish its purposes, this chapter includes methods and
provisions for:
Ordinance No. 6295
March 12, 2010 Page 7 of 44
A. Restricting or prohibiting uses which are dangerous to health, safety, and
property due to water or erosion hazards, or which result in damaging increases in
erosion or in flood heights or velocities;
B. Requiring that uses vulnerable to floods, including facilities which serve
such uses, be protected against flood damage at the time of initial construction;
C. Controlling the alteration of natural floodplains, stream channels, and
natural protective barriers, which help accommodate or channel floodwaters;
D. Controlling filling, grading, dredging, and other development which may
increase flood damage; and
E. Preventing or regulating the construction of flood barriers which will
unnaturally divert floodwaters or which may increase flood hazards in other areas.
F. Identif in the Re ulato Flood lain the S ecial Flood Hazard Area and
the Protected Area and the supporting technical data needed to delineate those areas.
G. Establishing a permit requirement so that all human development that may
affect flood hazards, water quality, and habitat is reviewed before it is constructed.
H. Setting minimum protection standards for all development to ensure that
the development will not increase the potential for flood damage or adversely affect
natural floodplain functions.
I. Setting minimum standards to protect new and substantially improved
structures from flood lama e.
J. S eci in additional habitat rotection criteria. Some ro~ects do not need
a floodplain permit (see ACC 15.68.1306, C); whereas other projects require a
floodplain permit, but do not require the habitat impact assessment required in this
chapter (see ACC 15.68.130D). For all other development projects, the applicant must
assess their impact on those factors that contribute to increased flood hazard and
degradation of habitat. If the assessment concludes that there will be an adverse effect
the permit will be denied, unless the project is redesigned to mitigate the
adverse mNa~±s effects. (Ord. 6161 § 1, 2008; Ord. 4820 § 1, 1995; Ord. 4357 §
2(1.4}, 1989.)
Article II. Definitions
15.68.050 Interpretation of language.
Unless specifically defined in this article, words or phrases used in this chapter
shall be interpreted so as to give them the meaning they have in common usage and to
give this chapter its most reasonable application. (Ord. 6161 § 1, 2008; Ord. 4820 § 1,
1995; Ord. 4357 § 2(2.0), 1989.)
15.68.060 Definitions.
As used in this chapter: 0 "Onno~l" mo~ne ~ rorri ioe~ fnr ~ rovio~n~ of rho r~i~~i onrrinoorinn rli~iieinn'e
R "Oros of ~h~lln~ni flnnrlinn" mo~ne ~ rloeirrn~~orl D(1 nr ~I-I manna nn rho ~Innrl
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,V,uN „ "Y,~. , ~u~... „~~,u u~N~„~ , ~,,i iyv
Ordinance No. 6295
March 12, 2010 Page 8 of 44
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0 A. "Adversely affectlAdverse effect" means effects that are a direct or indirect
result of the proposed action or its interrelated or interdependent actions and the effect
is not discountable, insignificant or beneficial. Discountable effects are extremely
unlikely to occur. Insignificant effects relate to the size of the impact and should never
reach the scale where a take occurs. Based on best judgment, a person would not: (1)
be able to meaningfully measure, detect, or evaluate insignificant effects; or (2) expect
discountable effects to occur. Beneficial effects are contemporaneous positive effects
without any adverse effects. In the event that the overall effect of the proposed action is
beneficial, but is also likely to cause some adverse effects, then the proposed action is
considered to result in an adverse effect.
B. "Base flood" means the flood having a one percent chance of being
equaled or exceeded in any given year. Also referred to as the "100-year flood." The
area subject to the base flood is the Special Flood Hazard Area (SERA) designated on
Flood Insurance Rate Maps as Zones "A," including AE, A0, AH, and Al-99.
C. "Base Flood Elevation" means the elevation of the base flood above the
datum of the effective FIRM.
1. The base flood elevation for the SFHAs of the City shall be as delineated
on the 100 year flood profiles in the Flood Insurance Study for the City.
2. The base flood elevation for each SFHA delineated as a "Zone AH" or
"Zone AO" shall be that elevation (or depth) delineated on the Flood Insurance Rate
Map. Where base flood depths are not available in Zone A0, the base flood elevation
shall be considered to be two feet above the highest grade adjacent to the structure.
3. Where base flood elevation data are not rovided on the Flood Insurance
Study for the City, base flood elevation data available from a Federal, State, or other
authoritative source shall be used, if available. Where base flood elevation data are not
available from other authoritative sources, applicants for approval of new subdivisions
and other proposed developments (including proposals for manufactured home parks
and subdivisions) greater than 50 lots or 5 acres, whichever is the lesser, shall include
such data with their permit applications. This data must be approved by the Floodplain
Administrator.
D. "Basement" means any area of the ~Id;nstructure having its floor
subgrade (below ground level) on all sides.
E. "Channel Migration Area" means the area within the lateral extent of likely
stream channel movement due to stream bank destabilization and erosion ra id stream
incision, agaradation, avulsions, and shifts in location of stream channels plus 50 feet.
1. The channel migration area shall be the total area occupied by the River
Channel, the Severe Channel Migration Hazard Area, and the Moderate Channel
Migration Hazard Area as delineated in the Green River Channel Migration Study
ublished b Kin Count dated December 1993 lus 50 feet.
Ordinance No. 6295
March 12, 2010 Page 9 of 44
2. Where more than one channel mi ration zone has been delineated the
q floodplain administrator shall use the delineation that has been adopted for other local
regulatory purposes.
F. "Critical Facilit " means a facilit necessa to rotect the ublic health
safety and welfare during a flood. Critical facilities include, but are not limited to,
schools, nursing homes, hospitals, police, fire and emergency operations installations,
water and wastewater treatment plants, electric power stations, and installations which
produce, use, or store hazardous materials or hazardous waste (other than consumer
products containing hazardous substances or hazardous waste intended for household
use).
G. "Development" means any manmade change to improved or unimproved
real estate in the Regulatory Floodplain, including but not limited to buildings or other
structures, mining, dredging, filling, grading, paving, excavation or drilling operations or
storage of equipment or materials subdivision of land, removal of more than 5% of the
native vegetation on the property, or alteration of natural site characteristics.
H. "Dry Floodproofing" means any combination of structural and non
structural measures that prevent flood waters from entering a structure.
I . "Elevation Certificate" means the official form (FEMA Form 81-31) used to
provide elevation information necessary to ensure compliance with provisions of this
ordinance and determine the ro erflood insurance remium rate.
J. "E uivalent Elevation" means havin similar relationshi to ordina hi h
water and to the best available 10-year, 50-year and 100-year water surface profiles.
K. "FEMA" means the Federal Emergency Management Agency, the agency
responsible for administering the National Flood Insurance Program.
L. "Fish and Wildlife Habitat Conservation Area" means lands needed to
maintain species in suitable habitats within their natural geographic distribution so that
isolated subpopulations are not created. These areas are designated by the City
ursuant to the Washin ton State Growth Mana ement Act WAC 365-190-080 .
M. "Flood" or "flooding" means a general and temporary condition of partial or
complete inundation of normally dry land areas from:
1. The overflow of inland or tidal waters; andlor
2. The unusual and rapid accumulation of runoff of surface waters from any
source.
N. "Flood Insurance Rate Map (FIRM)" means the official map on which the
Federal Insurance Administration has delineated both the areas of special flood hazard
and the risk premium zones applicable to the community.
0. "Flood Insurance Study" means the official report(s) provided by the
Federal Insurance Administration that includes flood profiles, the Flood a~
~'^^~'~^"y Insurance Rate Map, and the water surface elevation of the base flood. 1 IVV~dYY{.A
P. "Flood Protection Elevation (FPE)" means the elevation above the datum
of the effective FIRM to which new and substantially improved structures must be
protected from flood damage.
Q. "Floodway" means the channel of a stream or other watercourse and
the adjacent land areas that must be reserved in order to discharge the base flood
without cumulatively increasing the water surface elevation more than one foot. The
Ordinance No. 6295
March 12, 2010 Page 10 of 44
floodwa shall be as delineated on the Flood Insurance Rate Ma . Where floodwa data
Y p -Y are not provided on the Flood Insurance Study for the City, floodway data available from
a Federal, State, or other authoritative source shall be used, if available. Where
floodwa data is not available from another authoritative source a licants fora royal
of new subdivisions and other proposed developments (including proposals for
manufactured home parks and subdivisions) greater than 50 lots or 5 acres, whichever
is the lesser, shall include such data with their permit applications. This data must be
approved by the Floodplain Administrator. This provision does not apply to applications
for permits for small projects on large lots, such as constructing a single family home.
R. "Historic Structure" means a structure that:
1. Is listed on the National Register of Historic Places the Washin ton
Herita a Re ister or the Washin ton Herita a Barn Re ister or has been desi Hated a
landmark or been issued a Certificate of Appropriateness under the City's Historic
Preservation Ordinance.
2. Has been certified to contribute to the historical significance of a
re istered historic district.
S. "Hyporheic Zone" means a saturated layer of rock or sediment beneath
andlor adjacent to a stream channel that contains some proportion of channel water or
that has been altered by channel water infiltration.
T. "Im ervious Surface" means a hard surface area which causes water to
run off the surface in reater uantities or at an increased rate of flow from the flow
present under natural conditions prior to development. Common impervious surfaces
include, but are not limited to, roof tops, walkways, patios, driveways, parking lots or
storage areas, concrete or asphalt paving, gravel roads, packed earthen materials, and
oiled, macadam or other surfaces which similarly impede the natural infiltration of
stormwater.
U. "Lowest floor" means the lowest floor of the lowest enclosed area
(including basement) measured at the walking surface of the floor. An unfinished or
flood-resistant enclosure, usable solely for parking of vehicles, building access or
storage, in an area other than a basement area is not considered a building's lowest
floor; Nrv~v iu°u, as Ion as that s;~c" enclosure is not built so as to render the structure
in violation of the applicable nonelevation design requirements of this chapter found in
ACC 2 15.68.170A(7).
V. "Manufactured home" means a structure, transportable in one or more
sections, which is built on a permanent chassis and is designed for use with or without a
permanent foundation when connected to the required utilities. For floodplain
management purposes, the term "manufactured home" also includes park trailers, travel
trailers, and other similar recreational vehicles placed on a site for greater than 180
consecutive days. For insurance purposes, the term "manufactured home" does not
include park trailers, travel trailers, and other similar recreational vehicles.
W. "Manufactured home park or subdivision" means a parcel (or contiguous
parcels) of land divided into two or more manufactured home lots for rent or sale.
X. "Market value" shall mean the current assessed value as established by
the most recent tax roll of the Count Assessor in which the ro ert is located. An
Ordinance No. 6295
March 12, 2010 Page 11 of 44
applicant ma at a licant's ex ense rovide an a raisal to determine market
value.
Y. "Native Vegetation" means plant species that are indigenous to the
communit 's area and that reasonabl could be ex ected to natural) occur on the site.
Z. "Natural Floodplain Functions" means the contribution that a floodplain
makes to support habitat, including, but not limited to providing flood storage and
conveyance, reducing flood velocities, reducing sedimentation, filtering nutrients and
impurities from runoff, processing organic wastes, moderating temperature fluctuations,
and providing breeding and feeding grounds for aquatic or riparian species.
AA. "New construction" means structures for which the "start of construction"
commenced on or after the effective date of the ordinance codified in this chapter.
BB. "Protected Area" means the lands that lie within the boundaries of the
floodway, the riparian habitat zone, and the channel migration area. In riverine areas,
where a floodway has not been designated in accordance with this Chapter, the
Protected Area is comprised of those lands that lie within the boundaries of the riparian
habitat zone, the channel migration area, and the SFHA.
CC. "Recreational vehicle" means a vehicle:
1. Built on a single chassis;
2. Four hundred square feet or less when measured at the largest horizontal
projection;
3. Designed to be self-propelled or permanently towable by a light-duty truck;
and
4. Designed primarily not for use as a permanent dwelling but as temporary
living quarters for recreation, camping, travel, or seasonal use.
DD. "Regulatory Floodplain" means the area of the Special Flood Hazard Area
and all Protected Areas within the City of Auburn. It also includes newly designated
Special Flood Hazard Areas and Protected Areas that are delineated pursuant to City
Law.
EE. "Riparian" means of, adjacent to, or living on, the bank of a stream, lake,
pond, sound, or otherwaterbody.
FF. "Riparian Habitat Zone" means the water bod and ad~acent land areas
that are likely to support aquatic and riparian habitat as detailed in this chapter. The size
and location of the riparian habitat zone is dependent on the type of water body. The
riparian habitat zone includes the water body and adjacent lands, measured
perpendicularly from ordinary high water on both sides of the water body:
1. Marine and lake shorelines and T e S streams that are desi Hated
"shorelines of the State:" 250 feet.
2. Type F streams (fish bearing) streams greater than 5 feet wide and marine
shorelines: 200 feet.
3. Type F streams less than 5 feet wide and lakes: 150 feet.
4. Type N (nonsalmonid-bearing) perennial and seasonal streams with
unstable slopes: 225 feet.
5. All other Type N (nonsalmonid-bearing) perennial and seasonal streams:
150 feet.
Ordinance No. 6295
March 12, 2010 Page 12 of 44
-n -a _ition~ -t -e- -npa_na_n -a- !tat--zones !_n-c-u -e -a ito_na -an -areas -t -at- t e Floodplain Administrator determines are likely to support aquatic and riparian habitat.
GG. "Special Flood Hazard Area (SERA}" means the land subject to inundation
b the base flood. S ecial Flood Hazard Areas are identified b the Federal Emer enc
Management Agency in the scientific and engineering reports entitled "Flood Insurance
Study for King County, V1lashington and Incorporated Areas" dated April 19, 2005, and
any revisions thereto, and "Flood Insurance Study for Pierce County, UVashington and
Unincorporated Areas" dated August 19, 1987, and any revisions thereto, and
designated on associated Flood Insurance Rate Maps with the letters "A" including AE,
A0, AH, Al-99.
HH. "Start of construction" includes substantial improvement, and means
rl~~o fho hi iilrlinrr normi~ ~nr~e i~ei iorl• nrnvirlorl fho actual start of construction repair b1NlV ll IV N1,r111t.111 IVJ P.lVI I I IIL YY6AV IVVI.1Vb1, `./1 V Y Ib1Vb1 LI IV ,
,
reconstruction, addition, placement or other improvement ~~-mac ~n~iiir~ 1Qf1 rl~„e of +ho
that occurred before the permit's expiration date. The actual start means
either the first placement of permanent construction of a structure on a site, such as the
pouring of slab or footings, the installation of piles, the construction of columns, or any
work beyond the stage of excavation; or the placement of a manufactured home on a
foundation. Permanent construction does not include land preparation, such as clearing,
grading and filling; nor does it include the installation of streets and/or walkways; nor
does it include excavation for a basement, footings, piers, or foundation or the erection
of temporary forms; nor does it include the installation on the property of accessory
buildings, such as garages or sheds not occupied as dwelling units or not part of the
main structure. For a substantial improvement, the actual start of construction means
the first alteration of any wall, ceiling, floor, or other structural part of a building, whether
or not that alteration affects the external dimensions of the building.
II. "Structure" means a walled and roofed building including a gas or liquid
storage tankthat is principally above ground.
JJ. "Substantial Dama e: means lama a of an on in sustained b a
structure whereby the cost of restoring the structure to its before damaged condition
would equal or exceed 50 percent of the market value of the structure before the
damage occurred.
KK. "Substantial improvement" or "substantially improved" means any repair,
reconstruction, addition, replacement or improvement of a structure, the cost of which
equals or exceeds 50 percent of the ass°ss°d ~-a!uation market value of such structure
'I Rofnro fho imr~rn~iomon~ nr ror»ir i~ ~+~r~orl• nr 1 L.JVIVI V ~I IV 1111`.JI V Y VI I IV1 1~ VI I V1.JU11 IV V~u1 ~V\d, VI
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This term includes structures that have incurred "substantial damage," regardless of the
actual re airwork done.
The term does not, however, include either:
Ordinance No. 6295
March 12, 2010 Page 13 of 44
1. Any project for improvement of a structure to ~ correct existing
violations of state or local health, sanitary, or safety code specifications
that have been identified by the local code enforcement official and that are the
minimum necessary to assure safe living conditions; or
2. Any alteration of a structure listed on the National Register of Historic
Places or a State Inventory of Historic Places.
LL. "Variance" means a grant of relief from the requirements of this chapter
which permits construction in a manner that would otherwise be prohibited by this
chapter.
MM. "Water Typing" means a system for classifying water bodies according to
their size and fish habitat characteristics. The Washington Department of Natural
Resources' Forest Practices Water T in classification s stem is herb ado ted b
reference. The system defines fourwatertypes:
1. Type "S" =Shoreline: Streams that are designated "shorelines of the
State," including marine shorelines
2. Type "F" =Fish: Streams that are known to be used by fish or meet the
physical criteria to be potentially used by fish.
3. Type "Np" =Non-Fish Perennial streams
4. Type "Ns" =Non-Fish Seasonal streams
NN. "Zone" means one or more areas delineated on the FIRM. The followin
zones ma be used on the ado ted FIRM. The S ecial Flood Hazard Area is com rised
of the A Zone.
(a) A: SFHA where no base flood elevation is provided.
(b) A#: numbered A Zones (e.g., A7 or A14}, SFHA with a base flood
elevation.
(c) AE: SFHA with a base flood elevation.
(d) A0: SFHA subject to inundation by shallow flooding usually resulting from
sheet flow on slo in terrain with avera a de the between one and three feet. Aver-
ageflood depths are shown.
(e) AH: SFHA subject to inundation by shallow flooding (usually areas of
onding) with average depths between one and three feet. Base flood elevations are
shown.
(f~ B: the area between the SFHA and the 500-year flood of the primary
source of flooding. It may also be an area with a local, shallow flooding problem or an
area protected by a levee.
C: an area of minimal flood hazard as above the 500- ear flood level of
the primary source of flooding. B and C Zones may have flooding that does not meet
the criteria to be mapped as a Special Flood Hazard Area, especially ponding and local
draina a roblems.
(h) D: area of undetermined but possible flood hazard.
(i) X: the area outside the mapped SFHA.
(i) Shaded X: the same as a Zone B, above. (Ord. 6161 § 1, 2008; Ord.
4820 § 1, 1995; Ord. 4357 § 2(2.1- 2.17), 1989.}
Article III. General Provisions
Ordinance No. 6295
March 12, 2010 Page 14 of 44
15.68.070 Land to which this chapter applies.
This chapter shall apply to the Regulatory Floodplain a!! areas of s~,oc;u! flood
d~ within the jurisdiction of the city. (See ~ ~ "
r+nrlifi°rl in hie nh~n~°r ~nrl inr~nrnnr~~°rl h°r°in h\i r°f°r°nn° the C~~~° ~Innrl (`nn~rnl VV\d111V\d 111 ~I IIV VI IuN~VI u11U 11 IVVI 1.►VI ~A~V\d 1 IVI V111 N~ 1 VIVI VI IVV, V~{e1~V
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~^n° City of Auburn Regulatory Floodplain Map on file in the Office of the city Clerk.
(Ord. 6161 § 1, 2008; Ord. 4820 § 1, 1995; Ord. 4357 § 2(3.1 1989.)
15.68.080 Reserved .
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fnr ° (`if~i of ~i ihi irn " rl~ 1 QQF ~nrl ~n~i r°~iieinne °r°~n ~nii ~n~ > > > >
> >
~~nn ~r° nn nn~' Di ihi i ~~hi QM Th° i°~~ \IYI 4ll V V11 4l~ VVL IY141 , / \NNN , 41V111 VVVV 1 IIV VVL
~\i~il~hl° infnrm~finn fnr flnnrl h~~~rrl ~r°~ irl°nfifir+~~inn ~e ni Min°rl in D(`(` {►tYLAIIVINIV IIIIVIIIIWLIVII IVI IIVVW IIVIL{►tl\rt 6dIVVl I\dV11~111VWt.IV11 WV V1.it.1111Vtd
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. (Ord. 6161 § 1, 2008; Ord. 4820 §
1, 1995; Ord. 4357 § 2(3.2), 1989.)
15.68.090 Penalties for noncompliance.
No ,
nr ,'+°r°~ develo ment shall be undertaken without full compliance with the terms of VI NIIVI Vt.f
this chapter and other applicable regulations. Violation of the provisions of this chapter
by failure to comply with any of its requirements (including violations of conditions and
safeguards established in connection with conditions) shall be enforced pursuant to the
provisions of Chapter 1.25 ACC. (Ord. 6161 § 1, 2008; Ord. 4820 § 1, 1995; Ord. 4502
§ 20, 1991; Ord. 4357 § 2(3.3), 1989.}
15.68.100 Abrogation and greater restrictions.
This chapter is not intended to repeal, abrogate, or impair any existing
easements, covenants, or deed restrictions. However, where this chapter and another
ordinance, easement, covenant, or deed restriction conflict or overlap, whichever
imposes the more stringent restrictions shall prevail. (Ord. 6161 § 1, 2008; Ord. 4820 §
1, 1995; Ord. 4357 § 2(3.4), 1989.)
15.68.110 Interpretation.
In the interpretation and application of this chapter, all provisions shall be:
A. Considered as minimum requirements;
B. Liberally construed in favor of the governing body; and
C. Deemed neither to limit .nor repeal any other powers granted under state
statutes.
D. Maps referred to in this Chapter are for reference only, unless specified. If
the ma does not s ecificall indicate that it is the rims source of re ulation the text
of the applicable Code section shall control over any contrary information provide on a
map. (Ord. 6161 § 1, 2008; Ord. 4820 § 1, 1995; Ord. 4357 § 2 (3.5), 1989.)
Ordinance No. 6295
March 12, 2010 Page 15 of 44
15.68.120 Warning and disclaimer of liability.
The degree of ~f!ooc' property and habitat protection required by this chapter is
considered reasonable for regulatory purposes and is based on scientific and
engineering considerations. Larger floods and movement of channels outside of
mapped channel migration areas can and will occur on rare occasions. Flood heights
may be increased by manmade or natural causes. This chapter does not imply that land
outside the areas of special flood hazard or uses permitted within such areas will be
free from flooding or flood damages. This chapter does not imply that land outside the
regulated areas or development permitted within such areas will be free from flood or
erosion damage. This chapter shall not create liability on the part of the city, any officer
or employee thereof, ,for any damages to
ro ert or habitat that results from reliance on this chapter or any administrative
decision lawfully made thereunder. (Ord. 6161 § 1, 2008; Ord. 4820 § 1, 1995; Ord.
4357 § 2(3.6), 1989.)
15.68.125 A eals.
A. The Hearing Examiner shall hear and decide appeals and requests for
variances from the requirements of this chapter.
B. The Hearing Examiner shall hear and decide appeals when it is alleged
there is an error in an re uirement decision or determination made b the flood lain
administrator in the enforcement or administration of this cha ter.
C. Those aggrieved by the decision of the Hearing Examiner may appeal
such decision to the Superior Court.
D. Upon consideration of the factors of this Chapter and the purposes of this
chapter, the Hearing Examiner may attach such conditions to the granting of variances
as it deems necessary to further the purposes of this chapter.
Article IV. Administration
15.68.130 Establishment of and re uirement to obtain flood lain development permit.
A. A Floodplain development permit shall be obtained before construction or
development begins within the Regulatory Floodplainu
°e~~hlieh°rl in Orr 1 ti ~Q f1Qn The permit shall be for all e~ri in~i it°e innli irliny VV~VINIIVIIVVI 111 ! 1VV I V.VV.VVV. VII ViVL1.l1 VV II IVIViVIII l
development
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~ • .1_.______________~~evf~____~___~~t~___~o___ n____s __~vf___~~___t~___~ _ ~___f~~____~~~~~~n
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Ordinance No. 6295
March 12, 2010 Page 16 of 44
onrv' ~h~~ rlnr V 114 e~ ~ l I cl ~ ~J VI rJ I
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B. _A _d_evel_opmentgroject is n_ot sub'ect to the re uirements of this cha ter if
it is located on land that can be shown to be
1. Outside the Protected Area and
2. Higher than the base flood elevation.
The floodplain administrator shall inform the applicant that the project may still be
sub'ect to the flood insurance purchase requirements unless the owner receives a
Letter of Ma Amendment from FEMA.
C. Non-Development Activities. Activities that do not meet the definition of
"development" in this chapter are allowed in the Regulatory Floodplain without the need
for a floodplain development permit under this chapter, provided all other Federal, State,
and local requirements are met. The following are examples of activities not considered
development or "man-made changes to improved or unimproved real estate."
1. Routine maintenance of landscaping that does not involve grading,
excavation, or filling;
2. Removal of noxious weeds and hazard trees and re lacement of non-
native ve etation with native ve etation'
3. Normal maintenance of structures, such as re-roofing and replacing
siding, as long as such work does not qualify as a substantial improvement;
4. Normal maintenance of above ground public utilities and facilities, such as
replacing downed power lines;
5. Normal street and road maintenance includin fillin otholes re avin
and installing signs and traffic signals, but not including expansion of paved areas.
6. Normal maintenance of a levee or other flood control facilit rescribed in
the operations and maintenance plan for the levee or flood control facility; and
Plowing and other normal farm practices (other than structures or filling)
on farms in existence as of the effective date of this ordinance.
D. Activities Allowed With a Floodplain Permit. The following activities are
allowed in the Regulatory Floodplain without the analysis required in Section
15.68.160C or the habitat impact assessment required under ACC 15.68.130K,
providing all other requirements of this ordinance are met, including obtaining a
flood lain develo ment ermit:
1. Repairs or remodeling of an existing structure, provided that the repairs or
remodeling are not a substantial improvement or a repair of substantial damage.
Provided further, that no habitat impact assessment shall be required if the re air or
remodel does not expand the existing building envelope.
2. Expansion of an existing structure that is no greater than ten percent
beyond its existing footprint, provided that the repairs or remodeling are not a
substantial improvement or a repair of substantial damage. This measurement is
counted cumulative) from the effective date of this ordinance. If the structure is in the
floodway, there shall be no change in the dimensions perpendicularto flow.
Ordinance No. 6295
March 12, 2010 Page 17 of 44
3. Activities with the sole ur ose of creatin restorin or enhancin natural
_______________p_____p______________________________________q~ q___________________________________a functions associated with floodplains, streams, lakes, estuaries, marine areas, habitat,
and riparian areas that meet Federal and State standards, provided the activities do not
include structures radin fill or im ervious surfaces.
4. Development of open space and recreational facilities, such as parks,
trails, _and hunting grounds, that do not include structures, grading, fill, impervious
surfaces or removal of more than 5% of the native vegetation on that portion of the
property in the Regulatory Floodplain.
E. Other Activities
All other activities not listed in 15.68.130C or D are allowed, as long as they meet
all the other requirements of this ordinance, including the analysis required in Section
15.68.160 and the habitat im act assessment and an miti ation re uired under Section
15.68.135K and Section 16.58.135E and a floodplain development permit is issued.
Co~~inn of ~ i ihi irn (`i~~i (lrrlin~nno I~In /I 1 QF n~eeorl nn Ilonomhor 1 F 1 QQ~ (Ord. vvv~ivi i v vi i ~unr~.+i i i vi~y vi ~aii ic.~i ivy i rv. ~ i vv ~✓cwvvw vii vvvvi i inrvi
i v, i vvv.
6161 § 1, 2008; Ord. 4820 § 1, 1995; Ord. 4357 § 2(4.1), 1989.)
15.68.135 Floodplain Development Permit Application.
Application for a floodplain development permit shall be made on forms furnished
b the flood lain administrator and shall include but not be limited to
A. One or more site lans drawn to scale showin
1. The nature, location, dimensions, and elevations of the property in
question,
2. Names and location of all lakes, water bodies, waterways and drainage
facilities within 300 feet of the site,
3. The elevations of the 10- 50- 100- and 500- ear floods where the data
are available. Additionally, for property located within the SFHA, base flood elevations
for shall be included as re uired in ACC 15.68.060.8.3
4. The boundaries of the Regulatory Floodplain, SFHA, floodway, riparian
habitat zone, and channel migration area, delineated in accordance with this chapter,
5. The proposed drainage system including, but not limited to storm sewers
overland flow paths, detention facilities and roads,
6. Existing and proposed structures, fill, pavement and other impervious
surfaces, and sites for storage of materials,
All wetlands,
8. Desi Hated fish and wildlife habitat conservation areas and
9. Existing native vegetation and proposed revegetation (see ACC
15.68.161 D).
B. If the ro osed ro~ect involves re radin excavation or fillin the site
plan shall include proposed post-development terrain at one foot contour intervals.
C. If the proposed project includes a new structure, substantial improvement, or
repairs to a substantially damaged structure that will be elevated, the application shall
include the FPE for the building site and the proposed elevations of the following:
1. The to of bottom floor includin basement crawls ace or enclosure
floor)
Ordinance No. 6295
March 12, 2010 Page 18 of 44
2.______________The__top__of _the__next__hig_h_er_fl_oo_r
3. The top of the slab of an attached garage
4. The lowest elevation of machinery or equipment servicing the structure
5. The lowest ad~acent finished rade next to structure
6. The highest adjacent (finished) grade next to structure
The lowest adjacent grade at the lowest elevation of a deck or stairs
including structural support
D. If the proposed project includes a new structure, substantial improvement,
or repairs to a substantially damaged nonresidential structure that will be dry
floodproofed, the application shall include the FPE for the building site and the elevation
in relation to the datum of the effective FIRM to which the structure will be dry
flood roofed and a certification b are istered rofessional en ineer or licensed
architect that the dry floodproofing methods meet the floodproofing criteria in this
chapter.
E. The application shall include a description of the extent to which a stream,
lake or other water body, including its shoreline, will be altered or relocated as a result
of the proposed development.
F. The application shall include documentation that the applicant will a I
for all necessary permits required by Federal, State, or local law. The 1 INV Nr./r./11VV1
a lication shall include acknowled ment that the a licant understands that the final
certificate of occu anc will be issued onl if the applicant rccc~~~c~! rovides copies
of the required Federal, State, and local permits or letters stating that a permit is not
re uired.
G. The application shall include acknowledgment by the applicant that
representatives of any Federal, State or local unit of government with regulatory
authority over the project are authorized to enter upon the property to inspect the
development.
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! The riparian habitat zone shall be delineated on the site plan by the
applicant at the time of application for sub-division approval or floodplain development
permit for all development proposals within 300 feet of any stream or shoreline.
I. If the ro~ect is located in the Re ulato Flood lain and includes activities
not listed in ACC 15.68130C and D, the application shall include a Habitat Impact
Assessment. If that Assessment determines that impacts would result from the project,
the a lication shall also include a Habitat Miti ation Plan.
J. Habitat Impact Assessment
Unless allowed under ACC 15.68.130C or D, an application to develop in the
Regulatory Floodplain shall include an assessment of the impact of the project on water
quality and aquatic and riparian habitat. The assessment shall be c±hvr:
Ordinance No. 6295
March 12, 2010 Page 19 of 44
1. A Biolo ical Evaluation or Biolo ical Assessment that has received
q q concurrence from the US Fish and Wildlife Service or the National Marine Fisheries
Service, pursuant to Section 7 of the Endangered Species Act; or
2. Documentation that the activity fits within a Habitat Conservation Plan
approved pursuant to Section 10 of the Endangered Species Act; or
3. Documentation that the activity fits within Section 4(dl of the Endangered
Species Act; or
4. An assessment prepared in accordance with Regional Guidance for
Floodplain Habitat Assessment and Mitigation, FEMA Region X, 2010. The assessment
shall determine if the project would adversely affect ;~NNc±:
(a) The primary constituent elements identified when a s ecies is listed as
threatened or endan erect
(b) Essential Fish Habitat designated by the National Marine Fisheries
Service,
(c) Fish and wildlife habitat conservation areas,
(d) Vegetation communities and habitat structures
(e) Water quality,
(f} Water quantity, including flood and low flow depths, volumes and
velocities,
(g) The channel's natural mc^n~!:,rin:; lanform pattern and migration
rocesses,
(h) Spawning substrate, if applicable, and/or
(i) Floodplain refugia, if applicable.
K. Habitat Mitigation Plan
1. If the assessment conducted under ACC 15.68.135) concludes the project
is ex ected to have an adverse effect mN^c± on water quality and/or aquatic or riparian
habitat or habitat functions, the applicant shall provide a plan to mitigate those impacts,
in accordance with Re Tonal Guidance ~~for Flood lain Habitat Assessment and
Mitigation, FEMA Region X, 2010.
(a) If the project is located outside the Protected Area, the mitigation plan
shall include such avoidance, minimization, restoration, or compensation measures as
are appropriate forthe situation.
(b) If the project is located in the Protected Area, the mitigation plan shall
n~inirJnr~nn rnn~nrn~inr~ nr nnrv~r►nr~nn+inr► inc u e suc ~i v ~.ii~,i~.ii ivy, i vv«.ii ~;~i;;i i, ;;i ;,;;i i iN;,i iv~.i~i~.ii i appropriate measures as are
needed to ensure that there is no nv± !o~c o{ hN"±N± fNnv±on adverse effect due to the
ro~ect. Minimization measures are not allowed in the Protected Area unless the in
combination with other measures, result in no adverse effect. nv± !oc~ o{ hN"±N±
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2. The Ian's habitat miti ation activities shall be incor orated into the
proposed project. The floodplain development permit shall be based on the redesigned
project and its mitigation components.
L. Third-Party Review.
For the habitat impact assessment required in ACC 15.68.135(K) or the habitat
miti ation Ian required in ACC 15.68.135 ~L , the Cit ma re uire third-part review
when the professional opinions of the applicant's representative and the City's reviewers
Ordinance No. 6295
March 12, 2010 Page 20 of 44
cannot be reconciled. Third-party review requires the applicant's habitat impact
assessment, habitat mitigation plan, andlor additional technical studies to be reviewed
by an independent third party, paid for by the applicant but hired by the City. Third-party
review shall be conducted b a qualified consultant as defined in the Floodplain Habitat
Assessment and Mitigation Regional Guidance, FEMA Region X, 2010.
15.68.136 Floodplain Development Permit Expiration.
If there has been no start of construction, a floodplain development permit shall
expire 180 days after the date of issuance. Where the applicant documents a need for
an extension beyond this period due to conditions beyond the applicant's control, the
floodplain administrator may authorize one or more extensions.
15.68.140 Designation of the Floodplain Administrator.2
The Director of the planning and development department, or the Director's
designee, is hereby appointed to administer and implement this Chapter by granting or
denying floodplain development permit applications in accordance with its provisions.
15.68.141 Duties of the Floodplain Administrator.
Duties of the floodplain administrator shall include, but not be limited to:
A. Review all flood lain develo ment ermits to determine that the ermit
re uirements of this ordinance have been satisfied.
B. Review all floodplain development permits to determine that all necessary
permits have been obtained from those Federal, State, or local governmental agencies
from which prior approval is required, including those local, State or Federal permits that
may be required to assure compliance with the Endangered Species Act andlor other
appropriate State or Federal laws.
C. Review all floodplain development permits to determine if the proposed
develo ment is located in the Protected Area. If located in the Protected Area ensure
that the applicable provisions of this chapter are met.
D. Ensure that all development activities within the Regulatory Floodplain of
the City meet the requirements of this ordinance.
E. Inspect all development projects before, during and after construction to
ensure compliance with all provisions of this ordinance, including proper elevation of the
structure.
F. Maintain for public inspection all records pertaining to the provisions of this
cha ter.
G. Submit reports as required for the National Flood Insurance Program.
H. Notify FEMA of any proposed amendments to this ordinance.
I. Coo erate with State and Federal a encies to im rove flood and other
technical data and notify FEMA of any new data that would revise the FIRM.
J. Make interpretations where needed, as to the exact location of the
boundaries of the Regulatory Floodplain, the SFHA and the Protected Area (e.g., where
2 NOTE: The City Code Section 15.68.140, entitled Designation of the city of Auburn engineering division, was
repealed by Ord. 6161. (See also Ord. 4820 § 1,1995; Ord. 4357 § 2(4.2),1989.)
Ordinance No. 6295
March 12, 2010 Page 21 of 44
there _appears _to _be _a conflict _betwee_n _the _mapped _SF_HA _bound_arY _and actual field
conditions as determined by the base flood elevation and ground elevations).
15.68.150 Duties and responsibilities of the c;t;; °ny;ne°°rpublic works department.
Duties of the ~ public works department regarding flood hazard areas
shall include, but not be limited to:
A. Permit Review.
1. Review all development permits to determine that the permit requirements
of this chapter have been satisfied;
2. Review all development permits to determine that all necessary permits
have been obtained from those federal, state or local governmental agencies from
which prior approval is required;
3. Review all development permits to determine if the proposed development
is located in the floodway. If located in the floodway, assure that the encroachment
provisions of ACC 15.68160C are met.
B. Use of Other Base Flood Data. When base flood elevation data has not
been provided in accordance with ACC 15.68. 0608, the city engineer shall obtain,
review, and reasonably utilize any base flood elevation and floodway data available
from a federal, state or other sources in order to administer 5: ~
1F ~Qn this cha ter.
C. Information to Be Obtained and Maintained.
1. Where base flood elevation data has not otherwise been ~ provided
+hrni inh +ho ~Innrl Ines ir~nr+o c+i irl„ nr rorri iirorl in accordance with this chapter~rr
. obtain and record the actual elevation (in relation to mean sea level) of the
lowest habitable floor (including basement) of all new or substantially improved
structures, and whether or not the structure contains a basement; This information shall
be recorded on a current FEMA Elevation Certificate (FEMA Form 81-31), signed and
sealed b a rofessional land surve or current) licensed in the State of Washin ton.
2. For all new or substantially improved floodproofed structures:
a Verify and record the actual elevation (in relation to mean sea level), and
b Maintain the floodproofing certifications required in ,,°,CC '!5.58.18^0
this chapter.
3. Maintain for public inspection all records pertaining to the provisions of this
chapter. This information shall be recorded on a current FEMA Floodproofinq Certificate
(FEMA Form 81-65), professional engineer, currently licensed in the State of
Washin ton.
D. Alteration of Watercourses.
1. Notify adjacent communities and the Department of Ecology prior to any
alteration or relocation of a watercourse, and submit evidence of such notification to the
Federal Insurance Administration;
2. Require that maintenance is provided within the altered or relocated
portion of said watercourse so that the flood-carrying capacity is not diminished. If the
maintenance program does not call for cutting of native vegetation, the system shall be
oversized at the time of construction to compensate for said ve etation rowth or an
other natural factor that may need future maintenance.
Ordinance No. 6295
March 12, 2010 Page 22 of 44
E. Interpretation of FIRM Boundaries. Make interpretations where needed as
to exact location of the boundaries of the areas of special flood hazards (for example,
where there appears to be a conflict between a mapped boundary and actual field
conditions). The person contesting the location of the boundary shall be given a
reasonable opportunity to appeal the interpretation.
F. Appeals of determinations made pursuant to this chapter shall be filed with
the city's public works director within 20 working days after the final city engineer
decision is issued. The public works director shall have 15 working days to review the
appeal, determine whether to uphold of modify the city engineer's decision, and notify
the applicant of such determination. The decision of the public works director shall be
final. The city engineer's and director's decision shall be granted consistent with the
standards of Section 60.6 of the Rules and Regulations of the National Flood Insurance
Program (44 CFR 59-76). (Ord. 6182 § 4, 2008; Ord. 6161 § 1, 2008; Ord. 4820 § 1,
1995; Ord. 4357 § 2(4.3), 1989.)
15.68.151 Duties and responsibilities of the ~ ~ ~ planning
and develo ment de artment.
Duties of the c;ty ";~;!d;ny d;Y~;s;ons planning and development department shall
include, but not be limited to:
A. Permit Review.
1. Review all building-related development permits to determine that the
permit requirements of this chapter have been satisfied including building, addition and
alteration permits;
2. Review all building-related development permits to determine that all
necessary permits have been obtained from those federal, state or local governmental
agencies from which prior approval is required; and
3. Review all building-related projects to determine that the procedures for
building projects within a special flood hazard area have been applied.
B. Information to be Obtained and Maintained.
1. Where base flood elevation data is provided through the Flood Insurance
Study or required as in ACC 15.68.150(8} obtain and record the actual elevation (in
relation to mean sea level} of the lowest floor (including basement} of all new or
substantially improved structures, and whether or not the structure contains a
basement;
2. For all new or substantially improved floodproofed structures:
a Verify and record the actual elevation (in relation to mean sea level); and
b Maintain the floodproofing certifications required in ~,CC 15.08.130(,°,; this
chapter;
3. Maintain for public inspection all building-related records pertaining to the
provisions of this chapter. (Ord. 6161 § 1, 2008.)
Article V. Provisions for Flood Hazard Protection
Ordinance No. 6295
March 12, 2010 Page 23 of 44
15.68.160 ~°n., a~ Standards of the ~ ; ;y;; ;eer~
public works department.
A. Utilities.
1. All new and replacement water supply systems shall be designed to
minimize or eliminate infiltration of floodwaters into the system.
2. New and replacement sanitary sewage systems shall be designed to
minimize or eliminate infiltration of floodwaters into the systems and discharge from the
systems into floodwaters.
3. On-site waste disposal systems shall be located to avoid impairment to
them or contamination from them during flooding.
4. All new streets shall be designed to ensure the lowest finished surface
elevation is a minimum of one foot higher than the adjacent 100-year flood elevation.
5. All new development shall be designed and located to minimize the impact
on flood flows, flood storage, waterquality, and habitat.
(a) stormwater and drainage features shall incorporate low impact
development techniques that mimic pre-development hydrologic conditions, such as
stormwater infiltration, rain gardens, grass swales, filter strips, disconnected impervious
areas, permeable pavement, and vegetative roof systems.
(b). If the proposed project will create new impervious surfaces so that more
than 10 ercent of the ortion of the lot in the Re ulato Flood lain is covered b
im ervious surface the a licant shall demonstrate that there will be no net increase in
the rate and volume of the stormwater surface runoff that leaves the site or that the
adverse mN~c±effect is mitigated as required in ACC 15.68.135(J) and ACC
15.68.135 K ±h~ c"~N±vr
6. The site plan required in this chapter shall account for surface drainage to
ensure that:
(a). Existing and new buildings on the site will be protected from stormwater
runoff and
(b). The project will not divert or increase surface water runoff onto
neighboring properties.
Utilities
~~vllater wells shall be located outside the floodway and shall be protected
to the FPE.
.~c.la2~
B. Subdivision Proposals.
1. All subdivision proposals shall be consistent with the need to minimize
flood damage.
Ordinance No. 6295
March 12, 2010 Page 24 of 44
2. All subdivision proposals shall have public utilities and facilities such as
sewer, gas, electrical, and water systems located and constructed to minimize flood
damage.
3. All subdivision proposals shall have adequate drainage provided to reduce
exposure to flood damage.
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C. Floodway Standards
1. In addition to the other re uirements of this ordinance a ro~ect to develo
in the floodwa as delineated ursuant to this Cha ter shall meet the followin criteria:
(a) The applicant shall provide a certification by a registered professional
engineer demonstrating through hydrologic and hydraulic analyses performed in
accordance with standard engineering practice that the proposed development would
not result in any increase in flood levels during the occurrence of the base flood
discharge.
(b) Construction or reconstruction of residential structures is prohibited within
designated floodways, except for the following. The following exceptions must still meet
all other re uirements in the ordinance.
i Re airs reconstruction or im rovements to a residential structure which
do not increase the ground floor area, providing the cost of which does not exceed 50
percent of the market value of the structure either, (a) before the repair, or
reconstruction is started, or (b) if the structure has been damaged, and is being
restored, before the damage occurred. Any project for improvement of a structure to
correct existing violations of State or local health, sanitary, or safety code specifications
which have been identified by a local code enforcement official and which are the
minimum necessar to assure safe livin conditions or to an historic structure ma be
excluded from the 50 percent calculations.
(ii) Repairs, replacement, reconstruction, or improvements to existing
farmhouses located in designated floodways and located on designated agricultural
lands that do not increase the building's total square footage of encroachment and are
consistent with all requirements of WAC 173-158-075.
(iii) Repairs, replacement, reconstruction, or improvements to substantially
damaged residential dwellings other than farmhouses that do not increase the building's
total s uare foota a of encroachment and are consistent with all re uirements of WAC
173-158-076; or
(iv) Repairs, reconstruction, or improvements to residential structures
identified as historic structures that do not increase the buildin 's dimensions.
2. In riverine Special Flood Hazard Areas where a floodway has not been
delineated pursuant to this chapter, the applicant for a project to develop in the SFHA
shall provide a certification by a registered professional engineer demonstrating through
hydrologic and hydraulic analyses performed in accordance with standard engineerinq
ractice that the ro osed develo ment and all other ast or future similar
developments would not cumulatively result in an increase of flood levels during the
Ordinance No. 6295
March 12, 2010 Page 25 of 44
occurrence of the base flood dischar e b more than one foot. (Ord. 6161 § 1, 2008;
Ord. 4820 § 1, 1995; Ord. 4357 § 2(5.1), 1989.}
15.68.161 ~°nor~l e~~nrl~rrle Standards of the ^f 0 i ihi irn hi iilrlinrr rlivieinn VVIIVIVII VL~►1I1V1VlIVIV VILy VI ! 11.iNIn1111 N~,.111W111~ VIIYIVIVII
tanning and develo ment department.
In all areas of special flood hazard the following standards are required:
A. Anchoring.
1. All new construction and substantial improvements shall be anchored to
prevent flotation, collapse or lateral movement of the structure.
2. All manufactured homes must likewise be anchored to prevent flotation,
collapse or lateral movement, and shall be installed using methods and practices that
minimize flood damage. Anchoring methods may include, but are not limited to, use of
over-the-top or frame ties to ground anchors. This requirement is in addition to other
anchoring requirements for resisting wind forces. (Reference FEMA's "Manufactured
Home Installation in Flood Hazard Areas"guidebookfor additional techniques.)
B. Construction Materials and Methods.
1. All new construction and substantial improvements shall be constructed
with materials and utility equipment resistant to flood damage.
2. All new construction and substantial improvements shall be constructed
using methods and practices that minimize flood damage.
3. Electrical, heating, ventilation, plumbing, and air conditioning equipment
and other service facilities shall be designed andlor otherwise elevated or located so as
to prevent water from entering or accumulating within the components during conditions
of flooding.
C. Review of Building Permits. Where elevation data is not available either
through the Flood Insurance Study or from another authoritative source {~A~
,applications for building permits shall be reviewed to assure that
proposed construction will be reasonably safe from flooding. The test of reasonableness
is a local judgment and includes use of historical data, high water marks, photographs
of past flooding, etc., where available. Failure to elevate at least two feet above grade in
these zones may result in higher insurance rates.
D. Native Vegetation
The site Ian re uired for develo ment in the re ulato flood lain shall show
existing native vegetation.
1. In the riparian habitat zone, native vegetation shall be left undisturbed,
exce t if in connection with an activit allowed in the Re ulato Flood lain without a
permit, and except for activities with the sole purpose of creating, restoring or enhancing
natural functions associated with floodplains, streams, lakes, estuaries, marine areas,
habitat, and riparian areas that meet Federal and State standards, provided the
activities do not include structures, grading, fill, or impervious surfaces.
2. Outside the ri arian habitat zone removal of native ve etation shall not
exceed 35 percent of the surface area of the portion of the site in the Regulatory
Floodplain. Native vegetation in the riparian habitat zone portion of the property can be
counted toward this re uirement.
Ordinance No. 6295
March 12, 2010 Page 26 of 44
3. If the ro osed ro~ect does not meet the criteria of this cha ter a habitat
p p p l impact assessment shall be conducted pursuant to ACC 15.68.135K and, if indicated by
that assessment, a habitat mitigation plan shall be prepared and implemented pursuant
to ACC 15.68.135L. (Ord. 6161 § 1, 2008.)
15.68.170 ~;f;~ Additional standards of the
planning and development department.
In all areas of special flood hazard where base flood elevation data is provided
as set forth in ACC 15 5Q nQn or 1 ti 5Q,15niR;this cha ter, the following provisions are
required:
A. Residential Construction.
1. New construction and substantial improvement of any residential structure
shall have the lowest floor, including basement, elevated one foot or more above base
flood elevation. Enclosed crawl space areas no taller than three feet, measured from the
lowest ground within the crawl space to the bottom of the structural system directly
supporting the floor slab or sheathing above, shall not be considered as a basement.
2. Fully enclosed areas below the lowest floor that are subject to flooding are
prohibited, or shall be designed to automatically equalize hydrostatic and hydrodynamic
flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs
for meeting this requirement must either be certified by a registered professional
engineer or architect or must meet or exceed the following minimum criteria:
a A minimum of two openings having a total net area of not less than one
square inch for every square foot of enclosed area subject to flooding shall be provided;
b The bottom of all openings shall be no higher than one foot above grade;
~c Openings may be equipped with screens, louvers, or other coverings or
devices; provided, that they permit the automatic entry and exit of floodwaters..
3. The structure shall be aligned parallel with the direction of flood flows.
4. The structure shall be anchored to revent flotation colla se or lateral
movement of the structure.
5. All materials below the FPE shall be resistant to flood damage and firmly
anchored to prevent flotation. Materials harmful to aquatic wildlife, such as creosote, are
prohibited below the FPE.
6. Electrical heatin ventilation duct work lumbin and air-conditionin
equipment and other service facilities shall be elevated above the FPE. Water, sewage,
electrical, and other utility lines below the FPE shall be constructed so as to prevent
waterfrom enterin oraccumulatin within them Burin conditions of floodin .
Fully enclosed areas below the lowest floor that are subject to flooding are
prohibited; Provided, that those areas may be used only for parking, storage, or building
access and only if they are designed to automatically equalize hydrostatic flood forces
on exterior walls by allowing for the entry and exit of floodwaters. Designs for meeting
this re uirement shall either be certified b are istered rofessional en ineer or
licensed architect or meet or exceed the following minimum criteria:
a. A minimum of two openings having a total net area of not less than one
s uare inch for every square foot of enclosed area subject to flooding shall be provided.
b. The bottom of all openings shall be no higher than one foot above grade.
Ordinance No. 6295
March 12, 2010 Page 27 of 44
c.___________________peni_n_gs___may_____ e__eauippe______wt______screen_s~_____ouvers~___or__ot___er___covenn s or
devices provided that they permit the automatic entry and exit of floodwaters.
B. Nonresidential Construction. New construction and substantial
improvement to any commercial, industrial or other nonresidential structure shall either
have the lowest floor, including basement, elevated one foot or more above the level of
the base flood elevation... , As a_n _alternative to _elevation, _a new or substantial
improvement to a nonresidential structure and its toy°t"°r Y^~;t" attendant utility and
sanitary facilities, may be dry floodproofed in A Zones. The project shall meet the
following requirements:
1. Be floodproofed so that below one foot above the base flood level the structure
is watertight with walls substantially impermeable to the passage of water;
2. Have structural components capable of resisting hydrostatic and
hydrodynamic loads and effects of buoyancy;
3. Be certified by a registered professional engineer or a registered
professional architect that the design and methods of construction are in accordance
with accepted standards of practice for meeting provisions of this subsection based on
their development andlor review of the structural design, specifications and plans. Such
certifications shall be provided to the official as set forth in ACC 15.68.150(C)(2);
4. Nonresidential structures that are elevated, not floodproofed, must meet
the same standards for space below the lowest floor as described in subsection (A)(2)
of this section;
5. Applicants floodproofing nonresidential buildings shall be notified that
flood insurance premiums will be based on rates that are one foot below the
floodproofed level (e.g., a building constructed to one foot above the base flood level
will be rated as one foot below that level).
C. Manufactured Homes. All manufactured homes to be placed or
substantially improved within zones Al-30, AH, and AE shall be elevated on a
permanent foundation such that the lowest floor of the manufactured home is one foot
or more above the base flood elevation and be securely anchored to an adequately
anchored foundation system.
D. Recreational Vehicles. Recreational vehicles placed on sites are required
to either:
1. Be on the site for fewer than 180 consecutive days; or
2. Be fully licensed and ready for highway use, on wheels or jacking system,
attached to the site only by quick disconnect type utilities and security devices, and
have no permanently attached additions; or
3. Meet the requirements of subsection C of this section and the elevation
and anchoring requirements for manufactured homes.
E. Hazardous Materials. No new develo ment shall create a threat to ublic
health, public safety, or water quality. Chemicals, explosives, gasoline, propane,
buoyant materials, animal wastes, fertilizers, flammable liquids, pollutants, or other
materials that are hazardous, toxic, or a threat to water quality are prohibited from the
Regulatory Floodplain. This prohibition does not apply to small quantities of these
materials ke t for normal household use or to materials ke t in a roved containers
above the FPE or in a dry floodproofed non-residential building.
Ordinance No. 6295
March 12, 2010 Page 28 of 44
F_. _Small _Structures. _A low _cost _buildin_g_____su_ch _as _a __detach_ed_____ga_rage~
boathouse, pole barn, or storage shed, that is no larger than 500 square feet and is not
used for human habitation may be exempt from the elevation requirement of this
cha ter rovided
1. It is used only for parking or storage;
2. It is constructed and placed on the buildin site so as to offer minimum
resistance to the flow of floodwaters;
3. It is anchored to prevent flotation which may result in damage to other
structures;
4. All portions of the structure below the FPE must be constructed of flood-
resistantmaterials;
5. Service utilities such as electrical and heatin a ui ment meet the
standards of this chapter;
6. It has openings to allow free flowage of water that meet the criteria of this
chapter;
The ro~ect meets all the other re uirements of this cha ter.
G. Location of structures. Structures and other development shall be located
to avoid flood damage.
1. If a lot has a buildable site out of the Regulatory Floodplain, all new
structures shall be located in that area.
2. If a lot does not have a buildable site out of the Re ulator Flood lain all
new structures, pavement, and other development must be sited in the location that has
the least impact on habitat by locating the structures as far from the water body as
possible or placing the structures on the highest land on the lot.
H. Critical Facilities.
1. Construction of new critical facilities shall be to the extent ossible
located outside the limits of the Regulatory Floodplain.
2. Construction of new critical facilities shall be ermissible if no feasible
alternative site is available, provided
(a) Critical facilities shall have the lowest floor elevated three feet above the
base flood elevation or to the height of the 500-year flood, whichever is higher. If there
is no available data on the 500-year flood, the permit applicants shall develop the
needed data in accordance with FEMA mapping guidelines.
(b} Access to and from the critical facility shall be protected to the elevation of
the 500-year flood. (Ord. 6161 § 1, 2008; Ord. 4820 § 1, 1995; Ord. 4357 § 2(5.2),
1989. )
15.68.180 a~ ~~Community Acknowledgement of FEMA Map
Amendments.
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Ordinance No. 6295
March 12, 2010 Page 29 of 44
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~~~~Notwithstanding any other provision of this chapter, the city may permit
encroachments within the adopted regulatory floodway upon receipt of approval of the
Federal Insurance Administrator and completion of the conditions of this section.
1. Prior to a developer being authorized to encroach upon the adopted
regulatory floodway to an extent which will cause base flood elevation increases in
excess of those permitted in subsection A of this section, the developer shall provide,
for city review and submission to the Federal Insurance Administrator, the following:
a. A request for conditional approval of map change and the appropriate
initial fee as specified by Section 72.3 of 44 CFR Ch. I Federal Emergency
Management Agency or a request for exemption from fees as specified by Section 72.5
of 44 CFR Ch. I Federal Emergency Management Agency. Sections 72.3 and 72.5 of 44
CFR Ch. I Federal Emergency Management Agency are herein adopted by reference in
their entirety including any future amendments thereto;
b. An evaluation of alternatives which would not result in a base flood
elevation increase above that permitted under subsection A of this section
demonstrating why these alternatives are not feasible;
c. Documentation of individual legal notice to all impacted property owners
within and outside of the community, explaining the impact of the proposed action on
their property;
d. Written concurrence of the chief executive officer of any other
communities impacted by the proposed actions;
e. Written certification that no structures are located in areas which would be
impacted by the increased base flood elevation;
f. A request for revision of base flood elevation determination according to
the provisions of Section 65.6 of 44 CFR Ch. I Federal Emergency Management
Agency. Section 65.6 of 44 CFR Ch. I Federal Emergency Management Agency is
herein adopted by reference in its entirety;
Ordinance No. 6295
March 12, 2010 Page 30 of 44
g. A request for floodway revision in accordance with the provisions of Section
65.7 of 44 CFR Ch. I Federal Emergency Management Agency. Section 65.7 of 44 CFR
Ch. I Federal Emergency Management Agency is herein adopted by reference in its
entirety.
B. City review of changes to flood hazard data.
1. All requests to revise or change the flood hazard data, includin~q requests
for a Letter of Map Revision and a Conditional Letter of Map Revision shall be reviewed
by the floodplain administrator.
(a). The floodplain administrator shall not sign the Community
Acknowledgement Form for any requests based on filling or other development, unless
the applicant for the letter documents that such filling or development is in compliance
with this ordinance.
(b). The floodplain administrator shall not approve a request to revise or
change a floodway delineation until FEMA has issued a Conditional Letter of Map
Revision that approves the change.
(c) Upon receipt of the Federal Insurance Administrator's conditional approval
of map change and prior to the approval of the proposed encroachments, the developer
shall compensate the city for all costs incurred by the city which are associated with:
(1) The city's adoption of floodplain management ordinances incorporating
the increased base flood elevations and/or revised floodway reflecting the post-project
condition;
(2) The city's submittal of evidence to the Federal Insurance Administrator of
the city's adoption of said revised floodplain management ordinances.
3. Within three months of completion of the proposed encroachments, the
developer shall be responsible for providing certified record drawings andlortechnical or
scientific data to the city for submittal to the Federal Insurance Administrator.
2. If an applicant disagrees with the regulatory data prescribed by this
ordinance he/she ma submit a detailed technical stud needed to re lace existin
data with better data in accordance with FEMA mapping guidelines or Regional
Guidance for "!-C1D-~~,!`. Hydrologic and Hydraulic Studies FEMA Region X, 2010. If the
data in question are shown on the published FIRM, the submittal must also include a
request to FEMA for a Conditional Letter of Map Revision.
3. All new hydrologic and hydraulic flood studies conducted pursuant to this
chapter shall consider future conditions and the cumulative effects from anticipated
future land use changes in accordance with Regional Guidance for n~~~p_~c,~,
H drolo is and H draulic Studies FEMA Re ion X 2010. If there is an stud in
existence on the date this provision becomes effective that meets the rest of this
chapter's criteria, it may be used, even if it does not account for future conditions. (Ord.
6161 § 1, 2008; Ord. 4820 § 1, 1995; Ord. 4357 § 2(5.3), 1989.}
15.68.190 Developments within areas of special flood hazard
Notwithstanding any other provision of this chapter, the city may permit
developments within s~special flood hazard areas. Prior to approval for a
development which will increase the water surface elevation of the base flood by more
than one foot, a developer must comply with the requirements set forth in ACC
Ordinance No. 6295
March 12, 2010 Page 31 of 44
15.68.180(~A~c.~a3~). (Ord. 6161 § 1, 2008; Ord. 4820 § 1, 1995; Ord. 4357 § 2(5.4),
1989. )
15.68.200 Compensatory storage requirements.
A. Development proposals shall not reduce the effective n~^ flood storage
volume at base flood ~c.~a=~~elevation. Where fill, grading or other activities that may
displace the effective base flood storage volume are proposed, compensatory storage
shall be required. Compensatory storage shall:
1. Provide equivalent volume at equivalent elevations to that being displaced;
2. Hydraulically connect to the source of the flooding;
3. Provide compensatory storage in the same construction season as when the
displacement of flood storage volume occurs. Allowances may be granted on a case-by-
case basis to allow sequential construction if the timing of the work cannot meet
wintertimelflood construction schedules; and
4.Occur on site or, if approved by the city engineer, at a hydraulically connected
off-site location.
5. Provide documentation of a restrictive easement acceptable to the engineering
division to ensure continued existence of the compensatory flood storage.
6 The newly created storage area shall be graded and vegetated to allow fish
access during flood events without creating fish stranding sites.
B. Certification by a registered professional engineer may be required as
documentation that the compensatory storage requirement shall be met by the
development proposal. (Ord. 6161 § 1, 2008.)
Section 3. Amendment to City Code. Section 16.10.010 of the Auburn
City Code be and the same hereby is amended to read as follows:
16.10.010 Purpose and intent.
A. The city of Auburn contains numerous areas that can be identified and
characterized as critical or environmentally sensitive. Such areas within the city include
wetlands, streams, wildlife habitat, significant trees, geologic hazards, ground water
protection areas, and flood hazards.
B. The city finds that these critical areas perform a variety of valuable and
beneficial biological and physical functions that benefit the city and its residents.
Alteration of certain critical areas may also pose a threat to public safety or to public and
private property or the environment. The city therefore finds that identification,
regulation and protection of critical areas are necessary to protect the public health,
safety and general welfare. The city further finds that the functions of critical areas and
the purpose of these regulations include the following:
1. Wetlands. Wetlands perform a variety of functions that include maintaining
water quality; storing and conveying storm water and flood water; recharging ground
water; providing important fish and wildlife habitat; and serve as areas for recreation,
education and scientific study, and aesthetic appreciation.
Ordinance No. 6295
March 12, 2010 Page 32 of 44
Wetland buffers serve to moderate runoff volume and flow rates; reduce
sediment, chemical nutrient and toxic pollutants; provide shading to maintain desirable
water temperatures; provide habitat for wildlife; and protect wetland resources from
harmful intrusion.
The primary goals of wetland regulation are to avoid adverse effects to
wetlands~c.lA~~ ~ ; to achieve no net loss of wetland function and value -acreage
may also be considered in achieving the overall goal; to provide levels of protection that
reflect the sensitivity of individual wetlands and the intensity of proposed land uses; and
to restore and/or enhance existing wetlands, where possible.
2. Streams. Streams and their associated riparian corridors provide
important fish and wildlife habitat; help to maintain water quality; store and convey storm
water and flood water; recharge ground water; and serve as areas for recreation,
education and scientific study and aesthetic appreciation. Stream buffers serve to
moderate runoff volume and flow rates; reduce sediment, chemical nutrient and toxic
pollutants; provide shading to maintain desirable water temperatures; provide habitat for
wildlife; and protect stream resources from harmful intrusion.
The primary goals of stream regulation are to avoid adverse effects ~ to
streams and associated riparian corridors; to achieve no net loss of functions and
values of the larger ecosystem in which the stream is located; to protect fish and wildlife
resources; to protect water quality through appropriate management techniques; and,
where possible, to provide for stream enhancement and rehabilitation.
3. Wildlife Habitat. Wildlife habitat provides opportunities for food, cover,
nesting, breeding and movement for fish and wildlife; maintains and promotes diversity
of species and habitat; coordinates habitat protection with elements of the open space
system; helps to maintain air and water quality; helps control erosion; serves as areas
for recreation, education, scientific study, and aesthetic appreciation; and provides
neighborhood separation and visual diversity within urban areas.
The primary goals of wildlife habitat regulation are to avoid adverse effects
to critical habitats for fish and wildlife; to achieve no net loss of functions and
values of the larger ecosystem in which the wildlife habitat is located; to implement the
goals of the Endangered Species Act; to promote connectivity between habitat areas to
allow for wildlife movement; to provide multi-purpose open space corridors; and where
possible to provide for fish and wildlife habitat enhancement and rehabilitation that
reflect the sensitivity of the species.
4. Ground Water Protection Areas. Ground water protection areas provide a
source of potable water and contribute to stream discharge/flow. Such areas contribute
to the recharge of aquifers, springs and/or wells and are susceptible to contamination of
water supplies through infiltration of pollutants through the soil.
The primary goals of ground water protection regulations are to protect ground
water quality by maintaining the quantity of recharge; avoiding or limiting land use
activities that pose potential risk of aquifer contamination; and to minimize or avoid
adverse effects ~ to ground water protection areas through the application of
performance standards, and to comply with the requirements of the Federal Safe
Drinking Water Act and Washington Administrative Code that require Group A public
water systems to develop and implement a wellhead protection program.
Ordinance No. 6295
March 12, 2010 Page 33 of 44
5. Geologic Hazard Areas. Geologic hazard areas include lands or areas
characterized by geologic, hydrologic and topographic conditions that render them
susceptible to varying degrees of risk of landslides, erosion, seismic or volcanic activity.
The primary goals of regulating geologic hazards are to avoid and minimize
potential impacts to life and property by regulating and/or limiting land uses where
necessary, and to conduct appropriate levels of analysis and ensure sound engineering
and construction practices to address identified hazards.
6. Flood Hazard Areas. Floodplains help to store and convey storm water
and flood water; recharge ground water; provide important areas for riparian habitat;
and serve as areas for recreation, education, and scientific study. Development within
floodplain areas can be hazardous to those inhabiting such development, and to those
living upstream and downstream. Floods also cause substantial damage to public and
private property that results in significant costs to the public and individuals.
The primary goals of flood hazard regulations are to limit or condition
development within the nn_y oar floodNla;; ; Regulatory Floodplain to avoid substantial
risk of damage to public and private property and that results in significant costs to the
public and individuals; to avoid significant increases in peak storm water flows or loss of
flood storage capacity; a~d~~~t~~~~~~~e~f~~~t ~~~fe~tfv ~~~~~fb~~~a~~~~~~~~
to protect critical habitat for fish and wildlife, and to
meet the ur oses set forth in Cha ter 15.68 of the Auburn Cit Code. Re uirements
for the identification assessment alteration and miti ation of flood hazard areas are
contained in Chapter 15.68 ACC.
C. This chapter of the Auburn City Code and other sections as incorporated
by reference contain standards, procedures, criteria and requirements intended to
identify, analyze, and mitigate potential impacts to the city's critical areas, and to
enhance and restore degraded resources where possible. The general intent of these
regulations is to avoid impacts to critical areas. Inappropriate circumstances, impacts to
specified critical areas resulting from regulated activities may be minimized, rectified,
reduced and/or compensated for, consistent with the requirements of this chapter.
D. It is the further intent of this chapter to:
1. Comply with the requirements of the Growth Management Act (Chapter
36.70A RCW) and implement rules to identify and protect critical areas and to perform
the review of development regulations required by RCW 36.70A.215;
2. Develop and implement a comprehensive, balanced and fair regulatory
program that avoids impacts to critical resources where possible, that requires that
mitigation be performed by those affecting critical areas, and that thereby protects the
public from injury, loss of life, property or financial losses due to flooding, erosion,
landslide, seismic events, soil subsidence, or steep slope failure;
3. Implement the goals and policies of the Auburn comprehensive plan,
including those pertaining to natural features and environmental protection, as well as
goals relating to land use, housing, economic development, transportation, and
adequate public facilities;
4. Serve as a basis for exercise of the city's substantive authority under the
State Environmental Policy Act (SEPA} and the city's environmental review procedures,
Ordinance No. 6295
March 12, 2010 Page 34 of 44
where necessary to supplement these regulations, while also reducing the city's reliance
on project-level SEPA review;
5. Provide consistent standards, criteria and procedures that will enable the
city to effectively manage and protect critical areas while accommodating the rights of
property owners to use their property in a reasonable manner;
6. Provide greater certainty to property owners regarding uses and activities
that are permitted, prohibited, and/or regulated due to the presence of critical areas;
Coordinate environmental review and permitting of proposals involving
critical areas with existing development review and approval processes to avoid
duplication and delay pursuant to the Regulatory Reform Act, Chapter 36.706 RCW;
8. Establish conservation and protection measures for threatened and
endangered fish species in compliance with the requirements of the Endangered
Species Act and the Growth Management Act requirements to preserve or enhance
anadromous fisheries, WAC 365-195-925;
9. Alert members of the public, including appraisers, assessors, owners,
potential buyers or lessees, to the development limitations of critical areas and their
required buffers.
E. Best Available Science. The city has considered and included the best
available science in developing these regulations, consistent with RCW 36.70A.172 and
WAC 365-195-900, et seq. This has been achieved through research and identification
of relevant technical sources of information, consultation with experts in the disciplines
covered by this chapter, and consultation and requests for technical information
regarding best available science from state and federal resource agencies.
Preparation of this chapter has included the use of relevant nonscientific
information, including consideration of legal, social, policy, economic, and land use
issues. This reflects the city's responsibilities under numerous laws and programs,
including other provisions of the Growth Management Act, and the need to weigh and
balance various factors as part of decision making to accomplish municipal objectives.
This may result in some risk to the functions and values of some critical areas. The city
will also use its authority under the State Environmental Policy Act (SEPA) to identify,
consider and mitigate, where appropriate, significant adverse effects on critical
resources not otherwise addressed by the regulations of this chapter.
The city intends to review and monitor implementation of its critical areas
regulations and to use an adaptive management approach. It will make adjustments to
the regulations, as appropriate, in response to changing conditions, new information
about best available science, or empirical data indicating the effectiveness of its
regulatory program. This will occur in the context of the city's ongoing review and
revision of its comprehensive plan and development regulations pursuant to the Growth
Management Act.
Additional information, both scientific and nonscientific, regarding compliance
with WAC 365-195-915(c), including identification of risks to resources, is contained in
the findings and conclusions and the overall record supporting adoption of Auburn's
critical areas regulations. (Ord. 5894 § 1, 2005.)
Ordinance No. 6295
March 12, 2010 Page 35 of 44
Section 4. Amendment to City Code. Section 16.10.070 of the Auburn
City Code be and the same hereby is amended to read as follows:
16.10.070 Critical area review process and application requirements.
A. Pre-Application Conference. Apre-application conference is available and
encouraged prior to submitting an application fora project permit.
B. Application Requirements.
1. Timing of Submittals. Concurrent with submittal of a State Environmental
Policy Act (SEPA) checklist, or concurrent with submittal of an application for projects
exempt from SEPA, a critical area report must be submitted to the city for review when
the city believes that a critical area may be present. The purpose of the report is to
determine the extent, characteristics and functions of any critical areas located on or
potentially affected by activities on a site where regulated activities are proposed. The
report will also be used by the city to determine the appropriate critical area
classification and, if applicable, to establish appropriate buffer requirements.
2. Report Contents. Reports and studies required to be submitted by this
chapter shall contain, at a minimum, the information indicated in the provisions of this
chapter applicable to each critical area. The director may tailor the information required
to reflect the complexity of the proposal and the sensitivity of critical areas that may
potentially be present.
C. Consultant Qualifications and City Review. All reports and studies required
of the applicant by this section shall be prepared by a qualified consultant as that term is
defined in these regulations. The city may retain a qualified consultant paid for by the
applicant to review and confirm the applicant's reports, studies and plans if the following
circumstances exist:
1. The city has technical information that is unavailable to the applicant; or
2. The applicant has provided inaccurate or incomplete information on
previous proposals or proposals currently under consideration.
D. Review Process. This section is not intended to create a separate critical
area review permit for development proposals. To the extent possible, the city shall
consolidate and integrate the review and processing of critical area-related aspects of
proposals with other land use and environmental considerations and approvals. Any
permits required by separate codes or regulations, such as flood plain development
^n° ^nn+r^' permits or shoreline substantial development permits, shall continue to be
required. (Ord. 5894 § 1, 2005.)
Section 5. Amendment to City Code. Section 17.04.300 of the Auburn
City Code be and the same hereby is amended to read as follows:
17.04.300 Regulatory floodway.
"Regulatory floodway" means
~rli Ian rl i~i+
ni imi il~+i~i°I~i innr°~~inrr +h° ~nr~~°r ~i irf~n° °I°~i~~inn by mnr° ~h~n nn° fnn+ inrlir►~~°rl vu. ~ ~u~u~~ v y .y Y~c,«vi vu. ~c.~vv v ~ u y ~ ~ ~ ~u~ ~ ivv~, ~uivc.«vu
Ordinance No. 6295
March 12, 2010 Page 36 of 44
lir+~ .the _ch_an_neI _o_____a___stream___or
other watercourse and the adjacent land areas that must be reserved in order to
discharge the base flood without cumulatively increasing the water surface elevation
more than one foot at an oint.
Section 6. Amendment to City Code. Section 17.09.050 of the Auburn
City Code be and the same hereby is amended to read as follows:
17.09.050 Development requirements.
A. Lot Area and Dimensions. Each lot created by short subdivision shall
contain sufficient square footage and lot dimensions to meet the requirements of ACC
Title 18. Each lot to be served by an on-site sewage disposal system shall be a
minimum of 15,000 square feet in area and shall also meet the minimum lot area
requirements of the county department of health rules and regulations. Land contained
in access easements, tracts or panhandles shall not be included in lot area or lot
dimension calculations for the purposes of this section.
B. Every lot within a short subdivision shall be capable of being reasonably
served by public or private sewage disposal, water, storm drainage facilities and streets.
The city will not approve a short subdivision for which a building permit cannot be
issued because of insufficient infrastructure.
C. Conformance with Adopted Plans. Street, water, sewer and storm
drainage facilities adjacent to or within the short subdivision shall be in conformance
with adopted city ordinances, standards and policies. Easements for utilities
recommended by such plans shall be provided to the city, with the exact location of
such easements to be determined by the city engineer.
D. Floods, Flood Control and Storm Drainage.
1. Where any portion of the proposed short subdivision lies within an area of
special flood hazard or regulatory floodway, conformance with adopted city flood hazard
area ordinances, standards and policies shall be required.
2. A conceptual storm drainagelsite grading plan shall be required to be
submitted, as part of the short subdivision application, unless waived by the city
engineer.
3. The proposed subdivision should c"~!! have one or more new lots in the
Regulatory Floodplain set aside for open space use through deed restriction, easement,
subdivision covenant or donation to a ublic a enc . The densit of the develo ment in
the portion of the development outside the Regulatory Floodplain may be increased in
accordance with applicable land use and subdivision regulations.
4. If a arcel has a buildable site outside the Regulatory Floodplain, it shall not be
subdivided to create a new lot, tract, or parcel within a binding site plan that does not
have a buildable site outside the Regulatory Floodplain. This provision does not apply to
lots set aside from development and preserved as open space.
E. Adjacent Streets. When any public street lying adjacent to the property
being short subdivided has insufficient width or for any other reason does not conform
to minimum street standards, in accordance with the city design and construction
Ordinance No. 6295
March 12, 2010 Page 37 of 44
standards, sufficient additional right-of-way shall be dedicated to the city and
appropriate improvements shall be made by the subdivider to conform the abutting half
of the street to such standards consistent with Chapter 12.64A ACC. Deferral of such
improvement requirements shall be in conformance with the city of Auburn design and
construction standards.
F. Access.
1. All short subdivisions shall border on an opened, constructed and maintained
public street. All lots within a short subdivision shall either border on an opened,
constructed and maintained public street or shall be served by a private street, access
easement, tract or panhandle having direct access to such a public street. Where
private streets and access easements are provided, they shall be improved or
guaranteed to the city of Auburn and be in conformance with the city of Auburn design
and construction standards.
2. All private streets, access easements and panhandles shall be capable of
meeting the fire access requirements of Chapter 15.36A ACC and the development
standards of Chapters 17.14 and 18.31 ACC, in addition to any other requirements of
this title, including, but not limited to, an adequate surface for access and minimum
turnaround requirements on dead-end streets or access easements as specified by the
fire department.
3. All ro osals shall ensure that all buildable lots shall have at least one access
road connected to land outside the Re ulato Flood lain with the surface of the road at
or above the FPE.
G. Dedication of Streets. Dedication of a public street or streets may be
required, whenever the city engineer finds that one or more of the following conditions
applies:
1. The general alignment of a proposed private street, access easement or
panhandle follows the general alignment of a future arterial as shown in the
comprehensive plan; or
2. The general alignment of a proposed private street, access easement or
panhandle can be reasonably modified to provide a desirable through-connection
between two or more existing or planned public streets or arterials; or
3. A public street would be necessary to provide adequate access to
adjacent property not subject to the proposed short subdivision.
H. Fire Hydrants. All lots within a short subdivision shall be capable of being
served by a fire hydrant as required by Chapter 13.16 ACC. Property zoned RC,
residential conservancy, may be exempt, provided the requirements of ACC 13.16.030
are met.
I. The final recorded subdivision plat shall include a notice that part of the
roperty is in the SFHA, riparian habitat zone andlor channel migration area, as
appropriate.
(Ord. 6239 § 1, 2009; Ord. 6186 § 12, 2008; Ord. 6006 § 3, 2006. Formerly
17.14.055)
Ordinance No. 6295
March 12, 2010 Page 38 of 44
Section Amendment to City Code. Section 17.14.110 of the Auburn
City Code be and the same hereby is amended to read as follows:
17.14.110 Floods and flood control.
The city may disapprove a proposed subdivision because of flood, inundation or
swamp condition if the city finds that such condition poses a threat to the public health,
safety or general welfare or causes a public nuisance.
Where any portion of the proposed subdivision lies within the ~ c;u! f!o
h~~~rrl ~r rho f~~~~,~-,y Regulatory Floodplain, the hearing examiner shall impose a 11{►tLVlltd VI ~IIV IIVVWYYW
condition on the preliminary plat requiring the subdivider to conform to the city's
h~~~rrl ,ro, Flood lain Develo ment requirements as set forth in Cha ter 15.68 of the 1 1 NL Vl 1 t.t Vl I V LA
Auburn City Code. In such cases, no development permit associated with the proposed
subdivision shall be issued by the city until said flood hazard area regulations have
been met.
The city may require dedication of land to any public body and/or the construction
of improvements and may impose other conditions necessary to protect against flooding
or inundation.
Section 8. New Section to City Code. Section 17.04.305 of the Auburn
City Code be and the same hereby is created to read as follows:
17.04.305 Regulatory Floodplain.
"Regulatory Floodplain" means the area of the Special Flood Hazard Area and all
Protected Areas within the City of Auburn. It also includes newly designated Special
Flood Hazard Areas and Protected Areas that are delineated pursuant to City
Ordinance.
Section 9. New Section to City Code. Section 17.04.335 of the Auburn
City Code be and the same hereby is created to read as follows:
17.04.335 Special Flood Hazard Area.
"Special Flood Hazard Area (SERA)" means the land subject to inundation by the
base flood. Special Flood Hazard Areas are identified by the Federal Emergency
Mana ement A , enc in the scientific and en ~ ineerin reports entitled "Flood Insurance
Study for King County, Washington and Incorporated Areas" dated April 19, 2005, and
any revisions thereto, and "Flood Insurance Study for Pierce County, Washington and
Unincorporated Areas" dated August 19, 1987, and any revisions thereto, and
designated on associated Flood Insurance Rate Maps with the letters "A" including AE,
A0, AH, Al-99.
Ordinance No. 6295
March 12, 2010 Page 39 of 44
Section 10. New Section to City Code. A New Section 18.70.025 of the
Auburn City Code be and the same hereby is created to read as follows:
18.70.025 Variances in Regulatory Floodplains
A. Subject to conditions, safeguards and procedures provided by this section,
the hearing examiner may be empowered to hear and decide applications for variances
from the terms of Chapter 15.68; provided the hearing examiner may approve a
variance only if the request conforms to all of the criteria in ACC 18.70.025.6. In
reviewing applications for a variance, the Hearing Examiner shall consider all technical
evaluations, all relevant factors, standards specified in other sections of this ordinance,
and:
1. The danger to life and property due to flooding or erosion damage;
2. The danger that materials may be swept onto other lands to the injury of
others;
3. The safety of access to the property in times of flood for ordinary and
emergency vehicles;
4. The expected heights, velocity, duration, rate of rise, and sediment
transport of the flood waters and the effects of wave action, if applicable, expected at
the site;
5. The susceptibility of the proposed facility and its contents to flood or
erosion damage and the effect of such damage on the individual owner;
6. The availability of alternative locations for the proposed use which are not
subject to flooding or channel migration and are not in designated fish and wildlife
habitat conservation areas;
The relationship of the proposed use to the comprehensive plan, growth
management regulations, and floodplain management program for that area;
8. The costs of providing governmental services during and after flood
conditions, including maintenance and repair of public utilities and facilities such as
sewer, gas, electrical, and water systems, and streets and bridges;
9. The potential of the proposed development project to destroy or adversely
.affect ~ a fish and wildlife habitat conservation area; and
10. The potential of the proposed development project to affect, or be affected
by, channel migration; and
11. Shall not result in a violation of this ordinance.
12. Must be compliant with the Endangered Species Act.
B. The examiner must enter findings of fact and conclusions of law which
support the following criteria and any conditions. No variance shall be granted to the
requirements of Chapter 15.68 ACC unless the applicant demonstrates that:
1. The development project cannot be located outside the Regulatory
Floodplain;
2. An exceptional hardship would result if the variance were not granted;
3. The relief requested is the minimum necessary;
Ordinance No. 6295
March 12, 2010 Page 40 of 44
4. The applicant's circumstances are unique and do not represent a problem
faced by other area properties;
5. If the project is within a designated floodway, no increase in flood levels
during the base flood discharge would result;
6. The project will not adversely affect fish or other wildlife habitat;
If the issue is not specific to the property, but is a problem faced by other
properties, the remedy should be a revision to the ordinance ratherthan a variance.
There will be no additional threat to public health, safety, beneficial stream
orwater uses and functions, or creation of a nuisance;
8. There will be no additional public expense for flood protection, lost
environmental functions, rescue or relief operations, policing, or repairs to streambeds,
shorelines, banks, roads, utilities, or other public facilities; and
9. All requirements of other permitting agencies will still be met.
C. Variances requested in connection with restoration of a historic site,
building or structure may be granted using criteria more permissive than the above
requirements, provided:
1. The repair or rehabilitation is the minimum necessary to preserve the
historic character and design of the site, building or structure; and
2. The repair or rehabilitation will not result in the site, building or structure
losing its historic designation.
D. Variances to the provisions of ACC 15.68.161 and 15.68.170 may be
issued for a structure on a small or irregularly shaped lot contiguous to and surrounded
by lots with existing structures constructed below the FPE, providing the other variance
criteria are met. The applicant for such a variance shall be notified, in writing, that the
structure (i) will be subject to increased premium rates for flood insurance up to
amounts as high as $25 for $100 of insurance coverage and (ii) such construction below
the FPE increases risks to life and property. Such notification shall be maintained with a
record of all variance actions.
E. Variances pertain to a physical piece of property. They are not personal in
nature and are not based on the inhabitants or their health, economic, or financial
circumstances.
Section 11. Repeal of Section of City Code. Section 17.04.045 of the
Auburn City Code (Definitions -Area of special flood hazard.) is repealed in its entirety.
TEXT OF REPEALED SECTION
17.04.045 Area of special flood hazard.
"Area of special flood hazard" means the land within the floodplain in a
community subject to a one percent or greater chance of flooding in any given
year, as indicated in the Flood Insurance Rate Map (FIRM) program entitled
Flood Boundary and Floodway Map. (Ord. 6239 § 1, 2009.)
Ordinance No. 6295
March 12, 2010 Page 41 of 44
Section 12. Incorporation of Guidelines. The "Floodplain Habitat
Assessment and Mitigation Regional Guidance", developed by the Federal Emergency
Management Agency drafted and dated January 2010, and any subsequent
amendments or versions promulgated by the Federal Emergency Management Agency,
and the "Regional Guidance for Hydrologic and Hydraulic Studies, developed by the
Federal Emergency Management Agency drafted and dated January 2010, and any
subsequent amendments or versions promulgated by the Federal Emergency
ManagementAgency shall be on file with the City Clerk, and incorporated herein by this
reference, for use in connection herewith.
Section 13. Ministerial Corrections. The Code Reviser is authorized
and directed to change all references to "Flood Control Zone Permits" in the Auburn City
Code to "Floodplain Development Permit."
Section 14. Repeal of Moratorium. The moratorium on the filing, receipt,
and approval of applications for development in the floodplain created by Resolution
4416 and extended by Resolutions 4442, 4476, and 4535 is hereby terminated as of the
effective date of this Ordinance.
Section 15. Fee schedule. The City of Auburn Fee Schedule shall be
amended to include the following fees:
Planning Department Fees
Floodplain development permit (when other City of Auburn development permits
required) $0
Floodplain development permit (stand alone permit; no other City of Auburn
development permits required) $50.00
Ordinance No. 6295
March 12, 2010 Page 42 of 44
Habitat Impact Assessment Report Review Fee (stand alone submittal) $250.00
Habitat Mitigation Plan Review Fee (stand alone submittal) $250.00
Combined Habitat Impact Assessment /Mitigation Plan Review Fee $500.00
and shall be further amended to delete the following fee:
Public Works Department Fees
6. Flood Control Zone Permit: (Per Ordinance No. 5819)
Base permit fee $50.00
The City Clerk is authorized to insert amend the City of Auburn Fee Schedule
consistent with this section without any further action by the City Council.
Section 16. Implementation. The Mayor is hereby authorized to implement
such administrative procedures as may be necessary to carry out the directions of this
legislation. This authority specifically includes making non-substantive changes to the
municipal code sections amended in this ordinance in order to comply with the direction
of the federal agencies reviewing this ordinance.
Section 17. Severabili The provisions of this Ordinance are
declared to be separate and severable. The invalidity of any clause, sentence,
paragraph, subdivision, section or portion of this ordinance, or the invalidity of the
application thereof to any person or circumstance shall not affect the validity of the
remainder of this ordinance, or the validity of its application to other persons or
circumstances.
Section 18. Effective date. This Ordinance shall take effect and be in force
as interim regulations five days from and after its passage, approval and publication as
provided by law. If the City receives approval of the ordinance from the federal
Ordinance No. 6295
March 12, 2010 Page 43 of 44
agencies, provisions herein shall automatically be effective as permanent regulations,
with the effective date the same as the effective date of the interim regulations.
INTRODUCED:
PASSED:
APPROVED:
CITY OF AUBURN
PETER B. LEWIS
MAYO R
ATTEST:
Danielle E. Daskam, City Clerk
APPROVED AS TO FORM:
Daniel B. Heid, City Attorney
Published:
Ordinance No. 6295
March 12, 2010 Page 44 of 44
h rht
~F~TU~,T'r~✓ ~ . ~ ~ ~ ~
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Floodplain Habitat
Assessment and Mitigation
Regional Guidance
2010
0 FEM,t-~.Region 10
Regional Guidance
for
Floodplain Habitat Assessment and Mitigation
Produced by FEMA -Region 10
January 2010
FEMA
Region 10
For additional information or copies of this guidance: Federal Emergency Management Agency
Attn: Mitigation Division
Federal Regional Center, Region 10
130 228th St. SW
Bothell, WA 98021-9796
(425) 487-4600 www. fema. gov/regionx/nfipesa. shtm
Contents
Introduction l
Background l
Definitions l
When to Conduct a Habitat Assessment 2
Allowed Activities 4
Conducting the Assessment 6
Step 1. Describe the Project Area 6
l.l. Project Area Description 6
1.2. Project Area Map 7
Step 2. Describe the Proj ect Area's Habitat 8
2.1. Background Research 8
2.2. Protected Species Identification 9
2.3. Site Investigation .......................................................................................10
2.4. Habitat Narrative ........................................................................................11
2.5. Habitat Area Map .......................................................................................12
Step 3 . Describe the Project ..................................................................................13
3.1. Final Project ...............................................................................................13
3.2. Construction Process ..................................................................................14
3.3. Protection Measures ...................................................................................14
Step 4. Assess the Impact ......................................................................................15
4.1. Types of Impacts ........................................................................................15
4.2. Report Format ............................................................................................17
4.3. Effects Determination ................................................................................17
4.4. Assessment Report .....................................................................................18
Habitat Assessment and Mitigation - i - January 2010
Preparing the Mitigation Plan ...............................................................................18
Step 5. Review Mitigation Alternatives (Mitigation Sequencing) ........................19
5.1. Avoidance ..................................................................................................19
5.2. Minimization 20
5.3 . Restoration 20
5.4. Compensation 21
5.5. Select the Best Approach(es) 21
Step 6. Prepare the Mitigation Plan 22
6. l .Objective 22
6.2. Format 23
6.3. Minimum Standards 24
Reviewing Habitat Assessments and Mitigation Plans 24
References and Resources 26
Federal and State Regulations 26
Maps and Databases 26
Water Quality and Quantity 27
Mitigation 27
Additional References 28
Habitat Assessment and Mitigation - ii - January 2010
Acknowledgements
This guidance document was developed by Region X of the Federal Emergency
Management Agency, as part of its continuing effort to improve floodplain
management practices and assist communities in meeting the requirements of the
Endangered Species Act.
It was prepared with the advice and assistance of a special advisory committee
that included representatives from:
- City of Auburn
- City of Carnation
- City of Everett
- Island County
- Jefferson County
- King County
- City of Lacey
- Lummi Nation
- City of Monroe
- Pierce County
- San Juan County
- Snohomish County
- City of Tukwila
- Washington State Department of Ecology
- Whatcom County
- The National Marine Fisheries Service
This document was drafted by French & Associates, Ltd., Steilacoom, ESA
Adolfson, Seattle, and PBS&J, Seattle, through an arrangement with the Insurance
Services Office and the Community Rating System.
Habitat Assessment and Mitigation -iii - January 2010
Habitat Assessment and Mitigation - iv - January 2010
Introduction
Background
This Regional Guidance is written for communities in the Puget Sound Basin. It will assist them
in meeting the requirements and criteria of the Endangered Species Act (ESA) as clarified in the
Biological Opinion issued by the National Marine Fisheries Service (NMFS) on September 22,
2008. This Regional Guidance is intended for environmental planners, wildlife, Foodplain,
stream, and wetland scientists, and other qualified habitat professionals.
This document is designed to support the NFIP-ESA Model Ordinance, which was also prepared
by FEMA Region X. The Model Ordinance includes a Biological Opinion Checklist which
provides a summary of what is required of communities by the Endangered Species Act. For
further details on the Biological Opinion's requirements, see the Model Ordinance Introduction
section and the Biological Opinion text in Appendix E of the Model Ordinance.
Communities have the option of adopting the Model Ordinance or ensuring that their existing
regulations fulfill all the Biological Opinion's requirements. Sections in the Model Ordinance are
referenced in this guidance to help the reader match the requirements with the Biological
Opinion and NFIP regulations. Additional references included in this assessment are listed at the
end of the document.
This guidance was prepared with technical input from local officials, engineers, natural resources
scientists, and planners. It is designed to assist qualified habitat professionals, representing both
permit applicants and permit officials to ensure that new development will not adversely affect
the habitat of protected threatened and endangered species in floodprone areas, including those
areas associated with stream, lake, and marine water bodies.
Although the Biological Opinion addresses ESA listed salmonid species and Southern Resident
killer whales, the Model Ordinance and this guidance were developed to address potential
impacts to all ESA listed species.
Definitions
Four terms are used in this guidance and the Model Ordinance that may not be the same terms
used in a community's regulations: "Regulatory Floodplain", "Special Flood Hazard Area" (or
"SFHA"), "Protected Area," and "development." These terms are introduced in the Definitions
section of the Model Ordinance (Section 2). The first three are defined in more detail in Sections
3.1, 3.2 and 3.4 of the Model Ordinance.
The Regulatory Floodplain is comprised of the SFHA and the Protected Areas, where:
• The SFHA is the area subj ect to flooding by the base flood (as determined and mapped
for each community by FEMA within flood insurance studies and accompanying Flood
Insurance Rate Maps (FIRMS)); and
Habitat Assessment and Mitigation -1- January 2010
• The Protected Area is comprised of those lands that lie within the boundaries of the
floodway, the riparian habitat zone, and the channel migration area.
An example of how the Regulatory Floodplain, SFHA, and Protected Area interrelate is shown
on the next page. A community's ordinance may use a different term to delineate the same or a
larger area in order to reach the same objective of addressing adverse effects to aquatic and
riparian habitat in the most sensitive areas. However, as these terms are used throughout this
guidance, please refer to the full definitions included in Sections 2 and 3 of the Model Ordinance
in order to ensure full consistency with the Biological Opinion.
A fourth term is also used throughout this document. In Section 2, the Model Ordinance defines
"development" as
any man-made change to improved or unimproved real estate, including but not limited to buildings
or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations,
storage of equipment or materials, subdivision of land, removal of more than 5% of the native
vegetation on the property, or alteration of natural site characteristics.
When to Conduct a Habitat Assessment
Whenever a development project is proposed in the Regulatory Floodplain, the property owner
must obtain a floodplain development permit from the community (Section 4.1). Certain types of
projects can be permitted relatively quickly (see "Allowed Activities" on page 4). Applicants for
projects that are not listed as exempt from conducting a habitat assessment by the community's
floodplain management ordinance must assess the impact of the proposed development on
flooding and habitat.
An adverse impact on flooding is prevented through the ordinance requirements for a floodway
or encroachment analysis (Section 7.5) and compensatory storage (Section 7.6).
The impact of a proj ect on habitat is more complicated because there is often little or no
information on the site's natural features and different projects will have different impacts.
Therefore a habitat assessment is needed to 'identify those features and determine how the
proposed project will affect them (Section in the Model Ordinance).
There are only two circumstances where a habitat assessment would not be required:
1. Proj ects that are listed as exempt from conducting a habitat assessment in the
community's floodplain management ordinance; and
2. Projects that have undergone Section 7 consultation under the Endangered Species Act
(ESA) in order to obtain a federal permit.
It should be noted that projects requiring a federal permit under Section 404 of the Clean Water
Act would likely need a consultation process through the U.S. Army Corps of Engineers Regula-
tory Branch. The Section 404 permit process includes consultation with the US Fish and Wildlife
Service (USFWS), and/or NMFS. Such consultation is required as required under Section 7 of
the ESA.
Habitat Assessment and Mitigation - 2 - January 2010
Speciai Fiood Hazard Area and Floodway [hannei Migration Area Riparian Habitat Zone ~
_
~ ~~i t~ ~ ~ r~• ~ '
r~~ fiF a
.
iq'
~ ~ i~
~T
. v e
c • ".m§ i~.
F ~ 3 rt~
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fr
~ „ ~ P ri i+~., a;~e ~ •$k ie.~ ° f~ ~ :
, '~at q } T i,.~ ' . s'``. t .
~
~
~
~
~~i,~-"~ . ~u
a
Legentl ~
Stream centerline
h~
Fleodwray
x ffi"t
Riparian Nabitat 2one
ChannelMfgmtlonArea
~y"} Spetiat Flootl Hatard Area
0
'I PrumttedArea
e
This graphic shows the relative locations of the floodway, riparian habitat zone, and the channel migration area, the
determinants of the Protected Area. The Regulatory Floodplain includes all of the SFHA and all of the Protected Area.
Enforcing the ordinance throughout the Regulatory Floodplain is needed to comply with the Endangered Species Act.
A community can receive CRS credit if the Regulatory Floodplain extends beyond the SFHA.
Source: Pierce County, 2007, GeoEngineers, 2005; USDA, 2006 (Air Photo)
Habitat Assessment and Mitigation - 3- January 2010
If a permit applicant has prepared a Biological Evaluation or a Biological Assessment and has
received concurrence from USFWS or NMFS, the project is deemed to comply with the ESA. In
such cases, the additional habitat assessment requirements of this guidance are not required (see
Section 7.7.A of the Model Ordinance).
Once it is determined that a habitat assessment is needed, a step by step assessment process is
recommended in this guidance. This process is summarized in the flow chart on the following
page. Steps 1- 4 comprise the basic habitat assessment.
If the assessment finds an adverse effect, then the permit applicant must prepare a plan that
identifies steps the permit applicant will take to mitigate that impact (Section 7.8 in the Model
Ordinance and Steps 5 - 6 in this document) and must implement the mitigation plan.
It is recommended that applicants start with conceptual development plans and conduct a
preliminary impact assessment before they invest in detailed project plans and specifications.
Continued communication with community staff will also help identify problems and solutions
before too much time and/or money is spent on a proj ect that may require additional mitigation
measures.
A permit applicant should weigh the cost of preparing the assessment and the mitigation plan,
should one be needed, against the cost of locating the project outside the Regulatory Floodplain.
It may cost less in time and money to simply avoid the SFHA and the Protected Area.
Allowed Activities
A habitat assessment is not needed if it is not required for certain activities, as specified by the
community's Foodplain management ordinance. The Model Ordinance, in Sections 7.1 and 7.2,
identifies two types of activities that can proceed without the habitat assessment. The reader
must check the community's flood management ordinance because it may have a slightly
different list.
Section 7.1 o the Model Ordinance clarifies that some activities are not considered
"development" and therefore do not need a oodplain development permit, provided all other
State and local requirements are met. An example would be normal maintenance of structures,
such as re-roofing and replacing siding (provided they are not part of a larger proj ect that would
need a permit). The Model Ordinance's list is not included here, because the community's list
maybe different.
Section 7.2 of the Model Ordinance lists other activities which are allowed in the Regulatory
Floodplain without the floodway analysis or the habitat impact assessment required under
Sections 7.5 and providing they meet all the community's other requirements and a
Foodplain development permit is issued. Again, the Model Ordinance's list is not included here,
because the community's list maybe different and takes precedence.
Habitat Assessment and Mitigation - 4 - January 2010
Is the project in the
Regulated Floodplain?
YES~NO
~
Has a Bioiogical Evaluation been prepared
foY the project and have NMFS ahdlor USFWS
determined concurrence with the project
under Section 7 of the ESA 7 -
~YES~
NO
~
Is the development project
an allowed activity?
Conduct the Assessment ~YES- - - -
Step 1: Describe lhe ProjectArea NO
Step 2: Describe ihe Habitat
Step 3: Describe ihe Project
Step 4: Assess the Impact
Kli'11 the project cause_
an adverse impact?
Prepare the Mitigation Pla i NO
n YES
Step 5: Review Mitigation Allematives
Step 6: Prepare the Mitigation Plan
Redesign the project to incorporate the plan's
mitigation measures
Is the plan acceptable?
i YES
NO
~
Redesign the project or Proceed with the project,
the mitigation measures getting all required permits
Habitat Assessment Flow Chart
f-labitat Assessment and Mitigation - 5- January 2010
Conducting the Assessment
The following steps should be taken to adequately identify and address the impacts a proposed
project may have on habitat within the Regulatory Floodplain. In circumstances where an
approved habitat assessment (Steps 1 through 4) determines that no impacts to habitats
associated with ESA listed species will occur, development of a mitigation plan is not necessary.
However, for any activity requiring a habitat assessment within the Regulatory Floodplain, it is
highly likely that impacts to habitats associated with ESA listed species will occur. When habitat
impacts are identified, a mitigation plan must be prepared for the project, in accordance with
Steps 5 and 6.
Step 1. Describe the Project Area 4some,cases, The project area is generally the parcel being developthe project may extend
to a larger area, such as when a road to the parcelis;to be built or mp oved. Step 1 should
produce two documents:
l.l.
Project Area Description '
:z~ ~
If a Washington State Joint Aquatic Rrces Permit Applic tion (JARPA) form has been
prepared for the project, it will include all the project area°decription information needed for the
habitat assessment. The Washington Siate-JARPA°forrn templaie•can be found at:
www. nws.usace. army. mil/PublicMenu/Meriu.c fmsiteame=REG&pagename=Home_Page
~h~ ~
If the information is already bemg provided in a WashingtomState JARPA, the community may
accept the application foNrm as suff ei~nt for the,project area description. If a Washington State
JARPA has not been prepared for/tha-project, the,pcoject area description should include the
followmg iqformahon,
Location inform"atio'n:
~o°`dS eet address~
o City'and County
~
o Township'„section, ancl range
o Latitude nd 1'ongitude
o Tax parcel n mber(s) of the project location
v
o Type of ownership of the project (Federal, State, or locally owned public lands; tribal
lands; privately owned lands)
- Water resource information:
o Watershed name
o Water resource inventory area (WRIA). Information on Puget Sound basin WRIAs
can be found at the Washingron State Department of Ecology's watershed planning
webpage (http:/hvww.ecy.wa.gov/watershed/index.html) and mapping webpage
(http://www.ecy.wa.gov/services/gis/maps/wria/wria.htm)
Habitat Assessment and Mitiga[ion - 6- January 2010
o Water bodies in which work will occur, including water typing. For more information
on water typing and a map that designates the types for major water bodies, see the
Washington State Department of Natural Resources water typing webpage
(www.dnr.wa.gov/BusinessPermits/Topics/ForestPracticesApplications/Pages/fp_wat
ertyping.aspx)
o Water bodies bordering or adjacent to the project location, including water typing.
o Shoreline Management Areas associated with shorelines of the state, as managed by
the State Shoreline Management Act and local Shoreline Master Programs. Shoreline
Management Area information should include the Shoreline Environment designation
~
and a description of the approximate extent of jurisdiction. To identify associated
Shoreline Management Areas and Shoreline Envi'ronment designations, review the
jurisdiction's Shareline Master Program a~~ onfaet,the local permitting official.
i"' \ \
o Critical Areas associated with streams, desigriated pursua~t to the Gmwth
Management Act and the local critical ardordinance. CSritical areas management
information should include the critial areas designation and a,description of the
extent ofjurisdiction. ' <
- Fish and Wildlife Habitat Conservation A'reas`(name a d+short description). Fish and
Wildlife Habitat Conservation"'Areas are designated liyylocal governm nts pursuant to the
Growth Management Act Tfiey sould include w 2 rs of the state (i.e., Type S streams
and shorelines), habitats for speci s tha `ar,e`endange ed or threatened (including
designated critical habitats and areas wher'e-the presenee of listed species is documented),
,
~ \ ~".s'S'1s '4.r',01\
habitats for speoiesof-lo,c~al imporfance, and naturalTarea pr.eserves. The community
should have a list of-d'esignated FisNand W,ildlife~Habitat Conservation Areas and/or
criteria for d sigri ting them~
1.2. Project Area Map `T~,' A~ w`-~~~ v:,4....
Xy
!p~. The second,ifem needed for Ste 1*is a map'; dra„ wn to scale that delineates the following:
- ~T~ . ~ Parcel boundaries
- Area of\ the fimshed pr "ec4t (mcludmg roads)
\ 4.:..: \
- Any additional area(s) tfiaf`will be disrupted during construction (including access routes,
staging areas; nd areas to+be re-graded or filled)
~
- All water bodies
- Site topography, soiisand geology
- Fish and Wildlife Habitat Conservation Areas
- Existing native vegetation by vegetation community zones. For example, a map could
distinguish areas with existing coniferous forest cover vs. areas with existing shrub cover
vs. areas with existing meadow cover.
- Boundaries oP the following regulatory areas (see Section 3 of the Model Ordinance)
o Special Flood Hazard Area
o Floodway
Habitat Assessment and Mitigation - 7- January 2010
o Riparian habitat zone
o Channel migration area
- Depths of the 10 and 100-year floods at representative locations. This need only be
provided where flood data are available from existing studies or the community.
Step 2. Describe the Project Area's Habitat
During Step 2 of the habitat assessment, the applicant describes the existing habitat conditions of
. the project area. Tasks 2.1 and 2.2 of Step 2 are largely based on•existing scientific information
on the species use and habitat in the project vicinityr,
2.1. Background Research ~
Step 2 should start with an examination of existing s urces of information relevant to Ihreatened
or endangered species and their habitats in or near the project area. Tfie e,may be thorough
inventories already available. The following sources uld b~e c~hecke&\\ior-critical - The community's planning or environmental.pr,otecf~on.department areas
inventory maps, best availaBle s ience consistency"`~studies, designated Fisli and Wildlife
Habitat Conservation Areas, Shorel e,Master Prog am, flood control and floodplain
management plans, and watersliedkandliabitat studi
- The community's parks and/or natural resources departments for natural area studies
- National Marine Fistieri s Service ritical habitrai maps
(www.nmfs.noaa.gov/pr/sp cies/criticalhabitai.htm)
- US Fish and WildhfewServ'cet(critical ha6itat maps (http://criticalhabitatfws.gov/)
- USEwS National Wetland Inv`ento~ry-maps (www.fws.gov/wetlands/)
-lUSFWS and'NMFS ha~bitat'recoveryplans, when published for ESA listed species in the
project vicinity ~
X
o USFWS: ww~v.fws.gov/pacific
o~N~MFS: www.nwr.noaa.gov
- US Departm nt~of Agric ulture, Natural Resource Conservation Service soil survey maps
(http://websoilstirvey.nr6's;usda.gov/app/)
- Washington Departrrienf of Fish and Wildlife Priority Habitats and Species Database
(http://wdfw.wa.gov/1iab/phslist.htm)
- Washington State Department of Ecology Water Quality Assessment
(www.ecy.wa.gov/programs/wq/30')d/2008/index.html)
Flabita[ Assessment and Mitigation - 8- January 2010
2.2. Protected Species Identification
The review of the existing research should identify all federally-listed species and designated
critical habitats, Essential Fish Flabitat (EFH, defined by the Magnuson-Stevens Fishery
Conservation and Management Act) and affected EFH species, and Fish and Wildlife Habitat
Conservation Areas in, overlapping, or withitt 200 feet of the project site. The table below is an
example of how this information could be presented.
Occurr`ence of Listed ,Speciesand Critical Habdat.in or Neanith`e Project FArea'
3 ~ Sample'DisplaY)
r ,
Cntical _
.
Habitat r
7 '~Commori;Name yySci.entife,Name ESA Status,Jurisdiction j;, Present zq,
Puget Sound Evolutionarily Oncorhynchus Th eatened~ NMFS " Yes
Significant Unit (ESU) tshawytscha >
Chinook Salmon
~
Puget Sound Distinct O mykiss Threateried NMFS ~ None
Population Segment (DPS)
A:
Steelhead _N111
Coastal-Puget Sound DPS Salvelinu's Th~eatened USFWS Yes
Bull Trout conflue'ntus •
To determine what listed o posed species?an FH may,occur`in;the action area, check with
NMFS (www.nwr.noaa:gov) nd'ttie USFWS (www.fw gov%westwafwo/speciesmap.html) to
obtain a county list offederally listed/designated and propos d species and critical habitat.
EFH species-to-be.considered in.freshwater-„ systems:commonly include three species of Pacific
salmon: pink, coho nd Chiook sa`Imo If tfie.p~rojeac,t area includes estuarine and marine
systems numerous p c ei s~of groundfish and`coa~stal pelagic fishes may also need to be
considered~ ~
,
This task should'summanze thc biolog~cal:and ecological information that will be needed far the
11 t~?Appropriate iriformation on the species' life history, its habitat and
habitat assessmen
distribution, and other data on fac ors necessary to its survival, shoald be included to provide
background for analyses in lat r s'ections. It is important to note that even though the September
2008 Biological Opinion~foc Ised on salmon and EFH, all threatened or endangered species in
,
the project area need to be addressed in the assessment.
Existing documents can be referenced, where appropriate. Sources of existing species status
information include current NMFS Status Reviews, EFH information, current NMFS and
USFWS recovery plans, and Washington State Department of Fish and Wildlife management
recommendations (see the References section for links to these information sources). Another
source is the locally developed best available science documentation reports, which are required
to be prepared by each Puget Sound community for their critical areas standards under the
Growth Management Act.
Habitat Assessment and Mitigation - 9- January 2010
The Corps of Engineers' ESA Consultation /nitiation Template and NMFS' Consultalion '
Initiation Template and User's Guide provide similar guidance. This section's narrative could
follow the format and guidance provided in Section III.B Description of Species in these
Templntes. Both the Corps and NMFS use the following outline:
i. Biological requirements ii. Factors of decline .
a. Historical pressures on the species
b. Current pressures on the species
c. Limiting factors for recovery of the species
iii. Local empirical information (if available)
a. Current local population information Example Primary Constituent Elements
b. Ongoing monitoring programs (if any) (Chinook salmon and sleelhead trout, 50 CFR Part
c. Population trend of the species 226, Federal Register / Vol. 70, No. 170 / Friday,
/ September 2, 2005)
Following the description of the protected ~1 Freshwater spawning sites with water quantity
ecies, there should be a summaof the habitat and quality conditions and substrate supporting
sp ry spawning, incubation and larval development.
❑eeds f0[ eaCh SpeCiOS. ThiS SeCtiOn,Of th0 2. Freshwater rearing sites with water quantity and
narrative needs to identify and desccibeFY e key floodplain connectivity
factors that are important for the protected ~ 3. Freshwater migration corridors free of
species. These should include the primar.y~~ obstruction
constituent elements identified-in the fnal~rules 4. Estuarine areas free of obstruction
that list threatened and endangered species\\~\s. Nearshore marine areas free ot obstruction
Primary constituent'elema nts are tl eikey habitatf 6. offshore marine areas wim water quality
components required for an ESA listed species, ~ conditions and forage, including aquatic
as identified in the final critical habitat rules and invertebrates and fshes, supporting growth and
~-A/ '-1 maturation.
published/in the Federal Register for lis'tedl \l
species-(see e ple.in the box).',,:, V
~
2.3. Site Investigation
Tasks 2.1. and 2.2r'grve the appiicant guidance on where to look and what to look for regarding
species potentially'present at the site. Following completion of the first parts of Step 2, a site
visit is needed to dei rinine if there are habitat areas with which identified species have a
"primary association". "94abitatsof primary association" include critical components of the
habitats which, if altered, may~i-eduee the likelihood that the listed species will maintain and
reproduce over the long term. A site visit and determination of site-specific conditions is
necessary to determine what actual impacts ro ESA listed species, EI^H, arid associated habitats
may occur.
Habitats of primary association include, but are not limited to, winter ranges, migration ranges
and corridors, breeding sites, nesting sites, regular large concentrations, communal roosts,
roosting sites, staging areas, and foraging areas. This process must identify those areas discussed
in Step 2.2 as bein-, primary constituent elements for each ESA listed species within the project
area. For example, identification of Chinook sllmon habitat areas of primary association should .
Habita[ Assessment and Mitigation - 10 - January 2010
look for those constituent elements listed in the box above. This field work must include adjacent
lands and waters, upstream and downstream of the site.
The description of the project area habitat and conditions should also identify existing
modifications to the project site within the Regulatory Floodplain, including existing structures,
roads, impervious areas and graded ar filled areas. Any existing modification that is impairing
habitats of primary association and habitat functions identified and described in the next section
should be described. Including activities to restore habitat in these modified areas could help the
assessment conclude that there will be no adverse effects to habitat due to the project (see also
Task 3.3 of Step 3).
The Washington Department of Fish and Wildlife's Mana4emelnlt ecom mendations for
Washington's Priority Habitats: Ripurian (see Referen es anAesources section of this
guidance) describes common land uses and modificat ons ihat im
pau riparian habitats. The
om
References section lists guidance materials related to"other cmonifloodplain and aquatic
habitat types.
2.4. Habitat Narrative
<\,\210
The findings of the field investigatine,used to prepre adescription of the haliitat areas of
primary association that will need to batprotected. The naraiive for this paR of the assessment
report needs to describe the presence and qual.~t. y of,the natural features that relate to the primary
ientifed~in Tasks 2.2 and 23. As
constituent elements for all_species and habitat a eas'd
described in the final pa g~ap of Task 2.2 primar
y~contituent elements are the key habitat
~ , r `~.s-r.:.~.
components required,~-for an ESA listed species, asdidentifie,d:m~the fnal rules and published in
the Federal Register ~vh en speciesare listed
It is possible-that there \may.be.limit~ed;information available from the s4urces identified in Tasks
. ~i
21 and 2:2. The habitat-narrative should note where,ths occurs and clarify where statements are
/ , ~ . Ix -t. ~ `
based on°scientifc repor4s and data,and where they~,are based on the professional opinion of the
author ~
The habitat n~tive incl des-an as ssrrient of the components and processes for each of the
habitats of priinary ssociation id ntified during the site investigation. The narrative should
}.a;a
identify what components and processes have a high level of function and what components and
processes are impaired~by,previous site and/or area (i.e. watershed level, basin level)
modifications. The narratiue'~should include the following headings for each identified habitat
area to ensure that the assessment will cover all items required by the Biological Opinion
(Appendix A, part 3) and Section 7J.13 of the Model Ordinance:
A. The primary constituent elements. These are identified in the final rules that designated
critical habitat for listed threatened and endangered species (see the NMFS and USFWS
critical habitat map links within the References and Resources section to access final
rules for ESA listed species). For example, for an inland site with Chinook salmon habitat
(see box, previous page), the first three sections of the habitat narrative would cover
Preshwater spawning sites, freshwater rearing sites, and freshwater migration corridors.
Habitat Assessment and Mitigation - ll- January 2010
B. Water quality. Discussion of existing water quality should identify water quality levels
within project area water bodies and compare existing levels to state standards. The
standards for freshwater surface water quality in Washington State are set by WAC 173-
201 a and are detailed by the Department of Ecology (www.ecy.wa.gov/
programshvq/swqs/criteria.html). Information in Washington State's Water Quality
Assessment (303(d)) should be supplemented with any known site specific information
(information on 303(d) is found at www.ecy.wa.gov/Programs/wq/303d/index.html).
Local and county environmental managers or land use planners should be contacted to
assist in identifying relevant water quality information.
C. Water quantity. Site flood dynamics and hydrology sh6ould assessed. Flood and low
flow depths, volumes, velocities, and flow paths ha e an important effect on the way
habitat is formed. The habitat narrative should dsoribe [hese factors with an emphasis
t"" r \~X
placed on the effects of flood events on habitatsr.,Tributa ,ry streams, seeps, stormwater
outfalls, waterways that pass through the projct site, and otfie water sources should be
identifed and described. This discussion may rely on and refer' ce other flood and site
hydrology studies prepared for the project~and should be focused•on how flood dynamics
and hydrology impact local habitat areas.Generally a•q`ualitative asessment of water
tia
quantity should be sufficient„although projects~where, inore significant,impacts to water
quantity conditions may occur §liould indude quanfitaYive assessment of'e isting
conditions. \ \
D. Vegetation communilies and habitat~structhres. This should~include a discussion of
riparian vegetatio dwo~ody debns~along,the b nkstind'thioughout the mapped
channel migra'tion area. Faeshwater riparian.,conditions•should be characterized consistent
with the guidance.in Munagement Recomriiendations for"Washington's Prioriry Habitats:
I
Ripnrian. Characterization of marine shoreline conditions should be consistent with
guidance-from the W` shingto S te`Departments of Fish and Wildlife and Ecology
(L nd Use'Plann \g for, Salmon, SteelAead and Trout), and with other Puget Sound
~neaishore guid'anoe,matenals,listed in Yhe;References and Resources section of this
guRdance.
E. Spaw'itig9substrate (onlywneed d ior ESA listed fish species)
F. Floodplain refugia (onlyrneeded for ESA listed fish species)
4f -k ~V
2.5. Habitat Area Map
Once alI habitat areas of primary association are identified and described, they should be
delineated on a map. The map should be to the same scale as the project area map (Task 1.2) to
facilitate comparison of the habitat to be protected with the extent of the Regulatory Floodplain,
the Protected Area, the riparian habitat zone, and other relevant Features, such as watercourses
and wetlands.
Habitat Assessment and Mitigation - 12 - January 2010
Step 3. Describe the Project
There are two key parts of the project that need to be described at this stage of the assessment
report: the final project, i.e., what the area will look like and how it will be used when the
project is completed, and the constnzction process that will be Followed to get there. The final
project should be covered first. Measures taken by the developer to prevent or minimize damage
to the habitat areas should also be included and highlighted.
As with Task 1.1, if a Washington State Joint Aquatic Resources Permit Application (JARPA)
form has been prepared for the project, it will include all projecfdj scription information required
for the habitat assessment. JARPA is under the Washington,State Governor s Office of
Regulatory Assistance. More information and the JARPA/orm Yemplate can be found at:
www.ora.wa.gov/resources/permitting.asp.
l~
If the information is already being provided in arWashington State JAaRPA that includes the level
of detail described in this guidance, the comm nity may accept the apphcation form as sufficient
for the project description. ~
If a Washington State JARPA has not-been prepared~for-•theypro~ect, the project+a.~,rea description
should include the information included in Tasks 3.1 and 3.2 of this section.
3.1. Final Project .
i~
All features present when co s ction is fimshed should,be described. This includes:
C=~ _~V\ ~,I/
- A summary of the project mcluding all~features that will be present when construction is
nished ~
f ~V `
- Projeot ta ec gory (md"usYr'ial;~comriieroialz resid~ntial, institutional, transportation,
f - : r
re~eational.°ma~nt ~ance~~.environmenta,l.`eJnhancement)
K. ,
- All:structures, including b; a't launches, fences, docks, and pilings, etc.
- Roads bridges, cul evts; \ail\ n'~d°,~pavements
- All st cfures or facilit es that would impact water bodies or wetlands, including
aquacultu~`re;_buoys, miningl bank stabilization, channel modifications, culverts, dams,
levees ditche's; fshways," nioorage, outfall structures, etc. ,
- Above and underground'utilities
- Water supply
- Wastewater disposal
- Stormwater management facilities
- Non-native landscaping
Habitat Assessment and Mitigation - 13 January 2010
The level of detail for these descriptions may be generalized for those features located outside
the identified habitat areas. The features need to be shown on one or more maps that will
facilitate relating the project to the project area map ("I'ask 1.2) and the habitat area map (Task
2.5).
There should also be a description of:
- The ongoing activities that will be conducted at the site
- Ongoing activities that will affect adjacent areas, such as an increase in traffic, an
increase in stormwater runoff from the site, increased noise, and changes air quality.
3.2. Construction Process
At a minimum, this section should cover the fol i points:
- Land clearance (areas to be cleared and naCive vegetation that will be removed)
- Any work in water, including a descrip on of ~the m/ethods and m ie\_ als used
- Grading and filling
- Stormwater management measitres taken durmg construction
- Utility installation (includmg any ~~on siYewastewaterltreatment)
- Methods and techniques for construction ofstructures, mcluding buildings, roads,
bridges, paved.aeas;-retaining walls„shorehnc 1 modifications; and types of equipment.
- Constructiomphasmg and'anticipate\,d construction timing)
.
1.
- Mobihzation and.s at ging pla s.~
:
Tempo a'y~"co k~struction access°arid staging areas.
Maps and,a timeline are,needed to,show where and when each activity will occur.
3.3. Protection,Measures
There are sev~~
eral`Federal' State "and local regulatory requirements for developments to include
measures that minimrz~gxthcir imp;,act on the environment Others may be initiated by the permit
applicant These shoul~d be d ci~ibed here. They could include:
~
- Preserving a setback area from any disturbances
- Drainage/erosion contro] plan during construction
- Post-construction stormwater/drainage plan
- Use of low impact development techniques (which may eliminate or reduce runoff from
areasto be developed)
I-labitat Assessment and Mitigation - 14 - January 2010
- Actions to implement wetland mitigation plans
- Compensatory storage provisions to replace lost floodplain storage,
Those protection measures that benefit the construction process, such as a sedimentation basin,
should be included in the construction process timeline.
Step 4. Assess the Impact
The impact assessment must analyze the direct and indirect effects of the action on the aquatic,
riparian, and floodplain habitat areas identified in Step 2, as well as effects of future actions
reasonably certain to occur. Primary factors to be considere8tlinithe assessment of impacts
include:
- Proximity of the action to identified habitat a eas
„5'*y;,
- Distribution, timing, and nature of the effec - t
- Duration
- Disturbance frequency, intensity, and severity
4.1. Types of Impacts
The References section at the end of this,documenf 7i sts reso rces~~ have additional guidance
far the assessment of impacts:
IN
Direct effects Accordmg to ESA rules and regulations, direct.effects occur at or very close to
the time of the action sel£,Examples could incl'ude construction noise disturbance, loss of
habitat, or sedimentation tliat cesults fr`omlhe con'struction activity. The discussion should
include informario on~the tempo; hI and-spatial„lirriits of tbe effects, species tolerances, severiry
of effect, mortality a0other forms of take, and expected habitat loss as a result of the proposed
action
VN
Direct impacts~a,project may ha\ve on a tiabitat area include, but are not limited to:
- Permanent~~ i~ clearing and ~rading of any habitat area;
A
N":, r~'-"I
- Temporary clearing and"grading of any habitat area during construction;
- Permanent structu es;}pa ements, etc., constructed within or placed within a habitat area;
~ Compensatory Floodplain storage requirements are included in Section 7.6 of [he Model Ordinance. This section
requires that compensatory storage areas must be graded and vegetated to allow fish passage during Flood events
without creating fish stranding sites. Areas of compensatory flood storage should be designed to create floodplain
habitat whenever feasible. Compensatory storage should not be used in areas prone to avulsions because lowering
Floodplain elevations or digging pits in these areas may increase the probability of an awlsion.
' Habitat Assessment and Mitigation - 1 5- January 2010
- Modification of a stream channel or side channel including bank stabilization measures
and removal or changes to large woody debris (other than stream restoration efforts); and
- Diversion of water that will change the hydrology of the area
Indirect effects: Indirect effects are also caused by or result from the proposed action, however
they are likely to occur later in time. They may occur outside of the area directly affected by the
action. Indirect impacts include, but are not limited to:
- Disrupting high or low stream flows, including impacts from stormwater runoff;
- Contributing to sedimentation that fills in substrate; :
- Blocking a corridor that connects habitat areas; °
- Increases in water body temperature and othercwate q ality parameters through removal
of riparian vegetation; ~v ~
- Disturbance of riparian vegetation (for exa' mple, clearing vegetatiion to the edge of a
forested riparian area);
- Moving or removing large woody debris;
- Destabilizing banks and modifq'ing channel migrafiocesses; and
- Modifying wetland areas through°disturbance of adjalent vegetation or modification of
hYdrologY•
Interdependent and interre-~lated actions tDeterminmg,whether otfier activities are interrelated
to, or interdependentwith, the proposed project,should'be deti~mined by asking the question:
Would the o[her ucti'vities occur rn llie ubsen e'of the proposed projec! (i.e., do they depend on
the project for their juslifi ation or liave no indep ndent aitiliry without Ihe project)? If the
answer to these questions is iio theri=tlfe activit'tes are interrelated or interdependent and should
be analyzed,yvith the effects ofithetaction'.-, ~
Cumulative effects: Under the ESA, cumulative effects include the future effects of State, tribal,
local, or private actions thaY are~reasonably~certain to occur in the action area. Permit'officials are
required to review the cumulatiye~effects`ofa projecL If one project has a minimal impact and
looks like it should~be approved, ~there must still be a review of the impact of allowing all
similarly situated properties to copstruct similar projects. The result of everyone doing what
appears to bc a minor`projeot~coul'd have a major impact on aquatic and riparian habitat. 'I'he
permit applicant should keep this in mind during this assessment.
e;l/
Habitat Assessment and Mitigation - 1 6- January 2010
4.2. Report Format
The ouUine below is a variation on the NMFS and Corps guidance in Section V. Effects of the
Action in their Consultation Initiation Templates.
A. Direct effects
. First primary constituent element (e.g., freshwater spawning sites2);
2. Second primary constituent element (e.g., freshwater rearing sites);
3. Third primary constituent element (e.g., freshwater R~gration corridors);
4. Essential Fish Habitat designated by the National 1Vlarine Fisheries Service;
5. Fish and Wildlife Habitat Conservation Areas/ 6. Vegetation communities and habitat shuctures;
7. Water quality; .
8. Water quantity, including Flood and - lo fl w delumes and velocities;
3.
9. The channel's planform pattern and migration processes;
10. Spawning substrate, if applicable; nd/\~\~
11. Floodplain refugia, if applicable
B. Indirect effects (see the list o tn he,previous page andcmclude consideration of indirect "
effects to items A.l through A.1`l;,above, that are appLcable to the proposed project.
C. Effects from interdependent and in terrelated,actions c
D. Effects from ongang-pro~ect acti ities (e.g operations and3maintenance)
E. Effects determinahon ~^zk
F. Summary
4.3. Effects Determmahon\,
An effect"de' termmation needs to be made for each.identified habitat area. Determinations for
each a eacan then be used to make'an overall proj ct effect determination. For example, if there
are no effects to all the id ntified habitabareas, then the overall determination would be that the
project wouid fiave no effect~However if some habitat areas are affected, then the project would
be determinedto potentially have an effect. In such instances, effects determinations for each
identifed habital a`rea wouid inforin efforts to mitigate any adverse effects. It is important to
document how the eff cts deterininations were reached.
4
NMFS, USFWS, and the Corp`s use the following effects determination criteria:
~
- No Effect (NE): the project has no effeet whatsoever to the listed species or designated
critica] habitat.
2 Primary constitucnt elements are key habitat components for ESA Iisted species as specified in the Federal
Register at the time of critical habitat designation for listed species. Sce the discussion on page 10 of this guidance
for further inf'ormation. '
Habitat Assessment and Mitigation - 17 - January 2010
- May Affect, Not Likely to Adversely Affect (NLAA): the effects to the listed species or
designated critical habitat are insignificant and/or discountable. A determination of
NLAA would be made for those activities that have only a beneficial effect with no short
or long-term adverse effects.
- Likely ro Adversely Affect (LAA): the effects of the project will result in a short -or
long-term adverse effects on the identified species or designated habitat area.
If the effects determination is NLAA, the report should indicate what minimization and
conservation measures would help eliminate or minimize the impact. For example, the permit
applicant could time certain construction work to occur when the>species are not present in the
project area. [f such measures do not eliminate the potential%duerse effect(s), then mitigation
measures will be needed in the mitigation plan (steps 5- 6). •
4.4. Assessment Report
a .
If the assessment concludes No Effect (NE) oc.rMay Affect, Not Likely to,Adversely Affect
(NLAA) (with minimization and conservationV measures), then the report.s ould be prepared and
submitted to the community's permit office. For N~AA determinations thatc`nclude
minimization and conservation measures, the asse sment must include enougfi,detail to show
how the measures are related to potent aL`project imp cts. ~
\
The assessment report should indude\all the information needed to suppori the effects
determination and the rationale for reachi g the conclusion(s)\It could be organized to follow
Steps 1-4 as outlined m thi °s document The~level oPdeYil,should be commensurate with the
level of anticipated impacts. Projects with significant impacts or,potential Por significant impacts
(due to project [ype and%o~r project location) require,more detailed review and analysis.
If the assessment concl des L`ikely-t LAdversely Affect (LAA) or NLAA and there are no
~
minimizati n or co servatio ,measures included in~the project design, then the assessment will
r
need to pxoceed ot Step 5~`
Preparmg the MitigationTlan
The followi g sections (Step Sta d 6) provides guidance on preparing a mitigation plan,
.,.-Al
including reference 2o•other habitat-specific restoration and mitigation guidance materials
developed for the P geY Sound/region. The final objective of floodplain habitat mitigation should
be to ensure that there is, o~a dve`rse effect to habitat, in terms of features, area, and/or function.
s
Step 6, Task 6.1 of this guidan'ce provides additional guidance on mitigation objectives,
including specific requirements for mitigation within Yrotected Areas and the Regulatory
Floodplain.
For many development proposals, permi[ conditions and mitigation actions required to meet
other local and state permit requirements may also provide mitigation for the impacts determined
through Step 4 of this guidance. In such instances, permit conditions and mitigation actions may
ovedap to serve as mitigation for impacts to floodplain habitats as required by the local flood-
plain management ordinance. The conditions and mitigation proposed, however, must be
Habitat Assessment and Mitigation - 18 - Janoary 2010
sufficient to mitigate for all floodplain habitat impacts in order to meet the objective of no
adverse effect to habitat.
Step 5. Review Mitigation Alternatives (Mitigation Sequencing)
5.1. Avoidance
There are four major types of alternative mitigation approaches to rectify an adverse effect. They
are listed in order of preference and effectiveness: avoidance, minimization, restoration, and
compensation. They may work independently or in combination"1The final objective is to provide
r --d
sufftcient and appropriate mitigation to compensate for habitat impacts, in terms of features,
area, and/or function.
divoidance is the preferred approach. It is recommended thaE`a development project stay.out
of the Regulatory Floodplain rather than implernent activities need`e'cl-ta mitigate the project's
adverse effect on aquatic and riparian habitat.(Therefore, at this stage~the permit applicant
sh'ould give serious consideration to relocating o\ redesigning the proposecl project to avoid
floodplain habitat impacts and the need for a mitPgat\ plan~
~
'Che community may want to encourag fie,permit appl~cant to avoid the Regulatory Floodplain
with additional incentives. Puget Sound communities cuneritly use many strategies to encourage
conservation of certain areas by allowing for development at a1more intense level in other areas.
These are usually provi~ ns-of a zoning ord~i~nan e oseparateNdevelopment regulations. There
4~ `8"
are three approaches, amongst'others, that Rug\ jound Junsdiction's,use to encourage
conservation:
x< -
l. Providing density~mcentives to.indrndual;property owners: A density incentive or
. 9. ,
density credit,`yst m ~ ould~allo.~peo~`fie$Iand uses to occur at a more intense level
within a poi-tion,of a parcel.outside of the,floodplain as compensation for conservation of
(floodprone are s within the parcel. Fo example, if a 20 acre parcel is zoned for one acre
l4and half of thc paccel is iri~the Regulatory Floodplain, the communiry might consider
all w ng the ] 0"dry",ac`res to 6e`'d'eueloped with half acre lots, allowing the development
to still'co struct 20 lomes: This would allow for a higher densiry of development in a
portion of~the.property and;~would require the remaining, high habitat value floodplain to
be conserved.as a dedicated tract. This strategy is similar to clustering development
methods, such as-is,ofYen:used in planned unit developments. Under both approaches, the
overall project does~ ot e tceed the development density allowed by the zoning district.
2. Transferable development rights: Transferable development rights (TDR) systems have
been in limitcd usc by certain jurisdictions within the Puget Sound region in recent years.
TDR systems allow for the transfer of development density from one parcel of land (with
some conservation value, such as a floodplain or wetland) to another parcel or area that is
planned for higher density development. Implementation and administration of TDR
systems has proveu challenging in many circumstances, due to the required coordination
in establishing density receiving and density giving areas, and in negotiating density
Habitat Assessment and Mitigation - 19 - January 2010
credit values: However, a community, regional, or watershed based TDR system may be
a successful strategy for floodplain avoidance.
3. Tax relief for conservation lands: Tax relief is a financial incentive that has proven to
discourage development of sensitive lands. King County has an established system of
providing property tax relief for lands that are established as conservation areas. All
projects must meet certain criteria and approval is not automatic. Such a system could
provide an additional venue to encourage conservation of floodplain lands.
5.2. Minimization
If the entire project cannot avoid the Regulatory Floodpl~ain; ~Jbe that it can be designed to
minimize the areas of impact by keeping more disruptiv.e parts,of.the project out of identified
high value habitat areas. For example, while water access`may be neoessary for the project, the
design might place all buildings and pavements ou/t'of~the riparian hab~tat zone. Here are some
ideas for this approach:
\ <
- Site the project footprint away from the higher value habitat \areas.
/`=1
- Designate buffer areas that are not disturbed duiing or;after construction.(note that
Section 7.4 of the Model Ordinance,prohibits distucbing native vegetation in the riparian
habitat zone without mitigation
- Include vegetation enhancement ineasures,around~the site\"s,\active use areas.
Many adverse effects ar' jdue t~ disrup\oncaus'ed by co struction. E-lere are some ideas to
avoid these types of'problems
- Perform all work in dry ~weather and/or durmg the dry season
Incr~orporate.erosion and sedimentation control,measures
~Use vegetable oil,b sed hydraulic flwds in all equipment working in water
- Prepaie and tram crews,on a spil~;prevention and pollution control plan
- Storstage and refueleq ipment o tside the riparian habitat zone
\n K - Inspect equtpment dailylfoc leaks
~r~
- Time specific pfiases of`work to occur during "species work windows," when the species
are not present or~H+~~'llnot be affected
5.3. Restoration
A project's plans should include restoring or improving areas disrupted by the construction
process. Wetlands, channels, and riparian areas can be repaired or rebuilt aPter the land clearance,
grading and filling is done. All areas temporarily cleared should be re-vegetated with native
plants.
Habitat Assessment and Mitigation - 20 - January 2010
In some cases, restoration projects can be
improvements to conditions that existed before the project. The box to the right
~
provides an example, where a Jefferson ' F• 'F= a.
~
County stream was enhanced during a
bridge replacement project.
w !5 3~
,
5.4. Compensation
Restoration measures can mitigate the
4$° ~
impact of temporary disruption, as when ~ ' ~ 7;~ ~
an area is torn up for construction but
';..y, •.:sc
intended to remain as open space. Res- When the Tarboo Creek bridge was replaced in 2004,
toration can produce an equal or better .lefferson County used the opportunity to restore the
habitat at the Same loCation. stream to be more like it was before earlier bridges were
built. A long, narrow culvert was replaced with a deeper
channel, a wider opening, and woody debris. The former
Permanent changes to the land and water bridge and high stream velocities impeded travel of some
that cannot be avoided will need to be species of fish, including salmonids. The new
arrangement improves fsh passage and carries higher
compensated for. Compensation should flood Flows without overtopping the road.
always produce an equal or better habitat~_.,
even though it will be in a different loc iion (which may r may not be on the owner's propeRy).
It should be noted that the compensation~in e sure must account for the habitat functions and
elements identified in Step 2. Some funetions, such.as a-freshwater,migration corridor, will not
work in a different location
C ~•~::a t;~
The applicant should~also keep m mind that the`area required tor compensation is generally
greater than the area of impact. Because of the lengih of time it takes to successfully create a
stream side channel, wedand or<upland floodplain;habitat area, greater acreage should be
.
provided,to,comperi te for tRe lost hab t- aSee'the Auburn Narrows compensation
~
example, net page.) N X
5.5.
SelecttherBest Approac6(es)
1~"\
Selecting the best mitigation approaches for the proposed project is an iterative process. It should
consider avoidance as the prefer'red choice. If work must be done in a sensitive area, it should
,
consider the costs of re`strati n~and compensation. If those costs are too high, avoidance should
be reconsidered.
Selecting the best mitigation approach can and should be done in conjunction with the local,
State, and Federal regulatory offices. Involvement of their knowledgeable staff allows discussion
of the approaches and evaluation of preliminary project designs. This can save a lot of work
designing the mitigation project. Early and periodic meetings with appropriate regulatory
agencies can increase the likelihood of the mitigation plan meeling all regulatory requirements
and can reduce potential costs and schedule delays during the approval process.
Habitat Assessment and Mitigation - 21 - January 2010
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Auburn Narrows floodplain restoration project along lhe Green River, King Counly. This project was
funded by a developer of a nearby site in order to compensate for the adverse effect of a floodplain
development. The project included creation of side-channel habitat, off-channel habitat, and riparian
habilat.
- ESA Adolfson
~
~ x
Step 6. Prepare,-the Mitigat►on:Plan
61. ObJective
As noted in~Step\5, the objecri; ,of the mitigation plan is to assure that sufficient and appropriate
mitigation is provided to compensate for habitat impacts, in terms of features, acreage, or
function. If the ssessment cannotconclude that the project will have No Effect (NE) or May
Affect, Not Likely to-Adversely Affect (NLAA), then the mitigation plan needs to identify
activities that will resultLm,NE=orrNLAA. The plan document needs to be of sufficient detail to
demonstrale how this is done 'u'smg avoidance, minimization, restoration, and/or compensation
measures.
Objectives for mitigation are differentiated for those impacts occurring within Protected Areas
and those impacts occurring within the remainder of the Regulatory Floodplain. Mitigation
within the Protected Area must include such avoidance, restoration, and/or compensation
measures as needed to ensure that there is no adverse effect to habitat funetion due to the project.
The fourth type of mitigation alternative, minimization measures, are not allowed in the
Protected Area, unless they, in combination with other measures, result in no adverse effect to
habitat function (Model Ordinance Section 7.8.A.2).
,
Habitat Assessment and Mitigation - 22 - January 2010
The following are strategies by which the mitigation objective for Protected Areas may be
achieved:
- Doubling or tripling the area of compensatory mitigation to increase the mitigation ratio
(area of habitat impacts : area of compensatory mitigation provided).
- Identifying additional areas of previously degraded habitat within the project area and
developing and implementing a plan to restore them.
- Implementing restoration actions which are targeted as a high priority by an adopted and
approved species recovery plan, when such actions are identified within the site and/or
within the same basin or reach area, and approved by,l cal? state, and federal permitting
agencies. ~ C
For all mitigation, the final plan (construction level detail)~;slioul'd not be drafted until the local
permitting office(s), in coordination with state and feder'al agencies, as necessary, has agreed that
r
the conceptual mitigation plan would meet the objective. Coordinat~ n~with local permitting
ti
officers will ensure that the scope of the plannedqiiiiYigation will be commensurate with the scale
of the impacts and will meet the objectives id nYitied above.
¢ ,
6.2. Format { 2ental l Many communities have tried and truefomafs,for nviroassessments. It may be easier
for all involved to keep to that Format. Othen°vise Ghapter 2\6 f W.etlund Mi/igulion in
Washingron State Part 2: Deyeloping Mrtigution Plansrhas defailed,guidelines on what to
include in a mitigation,plan._Phere is a recommendedloutlirie.in Appendix C ofthat publication
which is geared to larger projects involving complex habitat-impacts and mitigation. Smaller less
complex projects in olving small impacts may(nof= equire all the information in the outline
because ii may not be elevant~~ pplicable. r~
Here is an examp el t~gat\plan outl e, - .
1. Int~ro.,duction, backgroun~d, etc~
2. The j~,e,.ct area, wi h rr`iap (taken~from Step 1 of the assessment)
3. The projc~rea's habitat;)ZWith map (taken from Step 2 of the assessment)
4. Project descriphon (taken from Step 3 of the assessment)
5. [mpact on habitat (taken* from Step 4 of the assessment)
6. Alternatives considered (taken from Step 5, this should note why some alternatives,
especially avoidance, were not selected)
7. Mitigation concept (an overall explanation of the measures)
8. Construction measures a. Grading plan, with existing and post-construction topographical maps
b. Construction methods (e.g. equipment to be used)
c. Construction schedule
Habitat Assessment and Mitigation - 23 - January 2010
9. Permanent measures
a. Surface water management
b. Vegetation plan
c. Permanent buffer areas
d. Etc.
10. PosY-construction monitoring and maintenance plan
11. Bond arrangements
6.3. Minimum Standards
At a minimum, the mitigation plan's components 7, 8 q 10.;=and 1 1 should be consistent with the
f i N \
mitigation guidance requirements of the Seattle District of the Corps of Engineers and Wetland
Mitigation in Washington Stale Part 2: DeveZoping Mitigation P~lans.>,(see Reference section)
and with the community's critical areas regulations!If there are inco sistencies between these
~
requirements, the standards that provide the highest level of environme tal`protection and the
greatest likelihood of mitigation success take prece\ c`~~~ h
~
Reviewing Habitat Assessments and Mitigat►on Plans
ti
This section provides guidance for the 1'ocal permit,official. The,following strategies may be used '
to ensure that habitat asses~sm`ents and mitiga`ion pl ans-are prepa edby a qualified individual or
company and meet the int/ent' ^o~f'the Model`O\rd\inan,ce;ajnd~ t,his guidance.
Establishing a List oflQualified Gonsul-
t3tttS: The cOmmunity CO'UlC1 prOVid'ea liSt Example Qualification Criteria
of qualified consultants to developers and" The following qualifcation criteria could be used by a
X ~ , community to ensure that habilat assessments and
land owners~who fiave expenence<m the
~ ~ mitigation plans are prepared by a qualified consultant -
81"e3. -,!~\ROth t' Stl'3t0 y~`f\ enSUl'Ing t}l~ Reports and lans shall be re ared b
ualified consultants are used,could:include p P P y persons wno
9 have a minimum of a bachelor's degree in wildlife or
developing:qUalif CatiOn CI'itena for authors fisheries habitat biology, or a related degree in a
of habitat assesments and mitigation platisZ biological field from an accredited college or universiry
~~,a~ with a minimum of four years experience as a
see the box to the nght for an exmple of practicing fish or wildlife habitat biologisf.
~e=.•0.
one community's crtteita. When used, qualifying crileria should include specifica-
XX ~.v"tions for all wildlife, fsheries, habitat, and environmenlal
Public Comment Penod• After"habitat professionals that could be relied upon to address the
aSSeSSmentS and mitigatiOn plans are broad array of habitats and conditions that occur in
floodprone areas.
submitted, [he permitting official may 11 require a public comment period before
assessment conclusions and/or mitigation plans are approved. This approach could include a
requirement that public notice be posted in a publication of record. The intent of the public
comment period would be to ensure that interested third parties would have ample opportunity to
review and comment on proposed projects. This could alert the local perrnit official to issues or
impacts not adequately addressed by an assessment or mitigation plan.
Habitat Assessment and Mitigation - 24 - January 2010
Third Party Review: The community may establish a system of third party review(s) by
qualified consultants or agencies. Third party review is frequently implemented by local
jurisdictions in the Puget Sound region for other environmental permits and approvals. The cost
of third party review could be passed on to the applicant. This may require establishment of a
third party review system in the ordinance.
Establishing a system of third party review could augment internal review within the local
jurisdiction. Another option for certain jurisdictions could be formalizing a system of internal
review where qualified staff would determine the adequacy of submittal materials.
Review Checklists: Permit staff could develop a review checkl~ ist7for assessment and mitigation
plan submittals. A checklist would likely need to be tailored,to, Is/pecific rypes of development activity due to the site- and habitat-specific nature of habitat'assessments and mitigation plans.
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Habitat Assessment and Mitigation - 25 - January 2010
References and Resources '
Federal and State Regulations
"Endangered Species Act - Section 7 Consultation, Final Biological Opinion," National Marine
Fisheries Service, September 22, 2008
Model Ordinance for Floodplain Management Under the Natronal Flood Lnsurance Program
and the Endangered Species Act, FEMA 2010.
NFIP Floodplain Management Requiremen[s A Study Guide'& U'esk Reference for Local
Officinls, FEMA 480, 2005, www.fema.gov/library/viewRecord.do?id=1443
Mitigation guidance and JARPA Permit information;+Army Corps of~Engineers; Seattle District.
http://www.nws.usace.army.mil/PublicMenu/Men `:cfm?sitename~REG&pagename=Forms
X
N
CRS Credit for Habilat Protection, FEMA, 2010,h.ttp //training.fema.gov/EM[Web/CRS/
w,
Maps and Databases Critical habitat maps:
, 11 - NMFS: http://www:nmfs.noaa.gov/pr/species/criticalhabitat:htm
- US Fish and Wildlife Servic~,e: http //criucalhabitat.f\w~s:gov/'
< ~1
Forest Water Typing Syslem, . Washington Department of Natural Resources
www.dnr.wa.goy,/Business P,crm ivtslTopics/F,orestPracticesA pp I ications/Pages/fp_water[yping.aspx
~
A Framex~ rk for Delinent \g Chdnnel MrgrationkZones. Washington State Department of
Ecology.and Washingto`n.Sfate Department of Tcansportation, Gcology Publication # 03-06-027,
2003. http`./%www.ecy.wa goul , biblio%030a 6027.htm1
, v
Nationa( Wetlandlnvenloiy maps for the Puget Sound Region, U.S. Fish and Wildlife Service,
http://www.fws gov/weNands/
Prioriry llubilats und Species (PHS) Database, Washington Department of Fish and Wildlife,
http://wdfw.wa.gov/hab/pNfistist~.htm
Wushingron Nntural Herilage Dalubuse, Washington Department of Natural Resources,
http:/hvww.dnr. wa.gov/Research Sc i ence/'Copi cs/Natural l-leritage/Page s/amp_nh.aspx
Washington State Soil Survey data, see the USDA Natural Resource Conservation Service maps
or online Web Soil Survey, http://websoilsurvey.nres.usda.gov/app/
Habitat Assessment and Mitigation - 26 - January 2010
Regiona[ Guidance for Hydrologic and Hydraulic Studies.in Support of the Model Ordinance for
Floodplain Management under the National Flood Insurance Program and the Endangered
Species Act, FEMA Region X, 2010, www.fema.gov/abouUregions/regionx/NFIP_ESA/
hydrologicandhydraulicstudies.pdf
Water Quality and Quantity
How to Meet Ecolog,y's Constructdon Stormwater General Permit Reguirements: A Guide for
Construction Sites, Washington State Department of Ecology, 2008,
http://www.ecy.wa.gov/biblio/9937.htm1 !te, 14 Standards for freshwater surface water qualiry in WashingtonyStDepartment of Ecology
K~
http://www.ecy.wa.gov/programs/wq/swqs/criteria.html
Stormwater Management Manual for Western Wps ton, Washingtdn State Department of
Ecology, 2005, http://www.ecy.wa.gov/programslwq/stormwater/manu~3html
R~
Washington State Water Qualiry Assessment Washington State ~Departmen ~of Ecology,
http://www.ecy.wa.gov/programs/wql3~03d/2008/index~°htm X.
"
I0
s , F
t
Water level data: -~"`w
~01:~
- US Geological Su~rvey: http //wa:water usgs gov/data/ ~,tt
- Washington Depar' tmen .~ofEcology ~
htt p:www.eay~wa.gov/programs/eaplflow/shu_mam:html
~0,
Mitigatwn W'~~~'
~',P
u.,~,
Engineertng with Natur,e Alternatrve Technaques to''Riprap Bank Stabilization, FEMA Region gz7 Xf 2009
EFil'!a ~ ~4~ ~At~
Sp
V
j'i.i'S
Floodplam ahd,'riparian corri'do~rs Washmgton Department of Fish and Wildlife (Bolton and
~ , t°.
Shelberg, 2001) http://wdfw w : a:gov/hab/ahg/floodrip.htm)
Habitat Conservation Planning Handbook, US Fish & Wildlife Service and National Marine •
Fisheries Service, 1996;h1tp //w,;ww.fws.gov/endangered/hcp/hcpbook.html
~V'
Land Use Planning for Salmon, Steelhead, and Trout: A Land Use Planners Guide to Salmonid
Protection and Recovery, Washington State Department of Fish and Wildlife and Washington
State Department of Ecology, 2009, http://wdfw.wa.gov/habitat/plannersguide/index.html
Management Recommendations for Washington's Prlority Hafiitats: Riparian, Washington
Department of Fish and Wildlife, 1997; http://wdfw.wa.gov/hab/ripxsum.htm
Protection and Restoration of the Nearshore Ecosystems of the Puget Sound, Puget Sound
Nearshore Partnership, 2004, http://www.pugetsoundnearshore.org/technical_reports.htm
Habitat Assessment and Mitigation - 27 - January 2010
Stream Habitat Restoration Guidelines, Washington Department of Fish and Wildlife, 2004,
http://wdfw.wa.gov/hab/ahg/shrg/index.htm
Wetland Midgation in Washington State Part 2: Developing Mitigation Plans, Washington
Department of Ecology, US Army Corps of Engineers, and US Environmental Protection
Agency, 2006, http://www.ecy.wa.gov/biblio/060601 lb.html
Additional References
Invasive species information: Washington State Noxious Weed Control Board.
http://www.nwcb.wa.gov/weed_lisUweed_list.htm ~
Low Impact Development, Puget Sound Partnership A ailable
www.psp.wa.gov/stormwater.php
~ . !
Landscape Planning for Washington's Wildl:fe Managtng for Btodiversi ,ty of Developing Areas,
Washington Department of Fish and Wildlife, 2009, http://wdfw.wa.govab/,phsrecs.htm
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Habitat Assessment and Mitigation - 28 - January 2010
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Regional Guidance for
Hydrologic and Hydraulic Studies
In support of the Model Ordinance for
Floodplain Management and the Endangered Species Act
2010
F'EM1~.Region 10
ou$tj-,,,~~ .
Regional Guidance for
Hydrologic and Hydraulic Studies
in support of the
Model Ordinance for Floodplain Management
under the National Flood Insurance Program
and the
Endangered Species Act
Produced by FEMA - Region 10
January 2010
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y o oyF~~N~o-` .
FEMA
Region 10
For additional information or copies of this guidance:
Federal Emergency Management Agency
Attn: Mitigation Division
Federal Regional Center, Region 10
130 228th St. SW
Bothell, WA 98021-9796
(425) 487-4600
www. fema. gov/regionx/nfipesa. shfm
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NFIP-ESA H&H Guidance - ii - January 2010
Contents
I nt ro d u c t i o n 1
Background 1
Hydrologic and Hydraulic Study Guidance 1
Future Conditions Floodplain Studies ) ..y 3
Background 3
Types of Future Conditions ~e,...~ 4
When to Analyze Future CondiUons 6
Future Conditions Hydrologic Analy\sis~`................................ 7
Future Conditions Hydraulic Analysis~.:; . 7
I'uture Conditions Summary
~
8
;
CIZS Credit for Future Condirions~Mapping 8
Hydraulic Models 10 .
Current Models ] 0
Regional G dano~.X f 7 I1
V
CRS Credit for:HydrauLc~Modelmg\ 12
~r---~_-~
Channel Migration Zones 13
Background :...............'.........................v........................................................ 13
C ~ ~ X
Biological Opmioln Reqmrements 13
Regonal Guidance\. 14
NZI
CRS Gredit for Mapping Channel Migration Zones 16
Appendix A. References .y.:............................................................................... A- 1
f
Appendix B. Flow Control-Exempt Surface Waters B- 1
NFIP-ESA H&H Guidance - iii - January 2010
Acknowledgements
This guidance document was developed by Region X of the Federal Emergency
Management Agency, as part of its continuing effort to improve floodplain
management practices and assist communities in meeting the requirements of the
Endangered Species Act.
IC was prepared with the advice and assistance of a special advisory committee
that included representatives from:
- Citv of Auburn
- City of Carnation
- City of Everett
- Island County
- Jefferson County
- King County
- City of Lacey
- Lummi Nation
- City of Monroe ` r .
- Pierce County
- San Juan County~
- Snohomish Counry\,N
- City of Tu ;wila
- Wasfiington SfaYe Deparfinent of Ecology
W a ~oun y\ ~
~
~
~The National~Marine fisbe~rie~s Service
While some comments were not incorporated; the reviews oY each agency in a
common e`ndeavor to make)this a useful guidance tool are appreciated.
/
This document was drafted by French & Associates, Ltd., Steilacoom, ESA
Adolfson, Seattle, and'PBS&J, Seattle, through an arrangement with the lnsurance
Services Office and the Community Rating System.
NFIP-BSA H&H Guidance - iv - January 2010
' Introduction
Background
This Regional Guidance is written for communities in the Puget Sound Basin to assist them in
meeting the requirements and criteria of the Endangered Species Act (ESA) as claiified in the
Biological Opinion issued by the National Marine Fisheries Service on September 22, 2008. The
primary audience for this guidance is engineers and other technical staff involved with mapping
flood hazards.
This guidance was prepared with input from local officials„eng ers, natural resources
scientists, and planners. It will assist local officials and developers determine the most
appropriate ways to prepare flood hazard data that mee Jhe`~e uirements of the National Flood
Insurance Program (NFIP) and the ESA.
~
This document is designed ro support the NFI-P-ESA Model Ordmance; .which was also prepared
by FEMA Region X.
t,
' k.~,.'..
Hydrologic and Hydraulic Study Guidance ! FEMA develops flood data and flood-hazard maps to support the NFIP. The data are
summarized in Flood Insurance Studies%a d the; ps are k own as Flood Insurance Rate Maps
(FIRMs). These products define the SpeciaINFlood`Hazard~Area (SFHA), which is the area
predicted to be inundated by_affood having~~l-percent'proliability of being equaled or exceeded
, r ^4~~'~ a ' . ~
in any given year (also-referred to as the 100-yearflood or liase flood). The SFEIA designates the
minimum area that a community mtthe NFIP must` egulate. The "Regulatory Floodplain," as
defined in the model ordmance, iMlie-SFHA plus those areas of riparian habitat and channel
migration area's tffat-extend'beyond,theaSFHA
There are normally three major phases to a I'EMA;flood study of a stream or river:
1. Assess the flows (usual y mvolving,a hydrologic study)
, v
~ ~
2. Determme flood elevations and the floodway (via a hydraulic analysis)
3. Map the floodplam (Si'HA) and floodway
Flood studies conducted foritlie+NFIP are prepared by mapping partners, including state and
regional agencies and loca go ernments. FGMA's mapping criteria are spelled out in Guidelines
and Specifications for Flood Hazard Mapping Partners (called Guidelines and Specifications in
this document), which are available at http://www.fema.gov/plan/prevent/fhm/gs_mainshtm.
Guidelines and Specifications includes technical appendices which are updated as necessary. The
, primary technical appendix that relates to the issues discussed in this Regional Guidance is
Appendix C: Guidance for Riverine Flooditig Arialyses and Mapping (FEMA, 2002).
NFIP-ESA H&H Guidance - 1- January 2010
This Regional Guidance is intended to supplement existing guidance for communities who wish
to prepare studies in consideration of special ESA provisions for Washington State as explained
in the Biologica! Opinion. The Biological Opinion identified three specific areas where study
techniques need to be adjusted to provide better hazard data:
- Use foreseeable future land use changes to establish Future base flood elevations,
- Use unsteady one-dimensional or two-dimensional hydraulic models to analyze complex
riverine systems when applicable, and
- Include the channel migration area as part of the regulato,ry floodplain.
These three subjects are covered in the following three sections.~Communities are not required to
use this guidance and it does not define the oniy approaclies.to~follow. However, communities
e~l`5l^I' \ t
that do follow this guidance will meet the ESA requicements as s~pelled out in the Biological
Opinion, and have a more effective program to red ce te dangers~and damage cau"sed by floods
and migrating stream channels. ~ ~
~ Each section also includes a discussioniof how each of the \threemelements of
~ N-
this guidance relate to potential Com un~ty~RatvingbSystem (CRS),c edits. More
information on the CRS Lcan-be found in Ap ~ pendix'D of the NFIP-ES'A Model
Ordinance and at http://www.fema.govlbusine.ss/nfip/crs shtm.
iry 3{
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NFIP-ESA H&H Guidance - 2- January 2010
Future Conditions Floodplain Studies
Background
Flood Insurance Rate Maps serve several purposes:
- They guide local floodplain management programs,
- They establish insurance premium rates, and
- They are used to determine when a flood insurance policy is required under the .
mandatory purchase requirement. ~
Afrer a review of the legal issues, FEMA's counsel concluded that FIRMs used for the last two
purposes need to be based on the current conditions on the•ground. In 2001, FEMA issued a
report, Modernizing FEMA's Flood Hazard Mapping,Program: Rcommendations for Using
Future-Conditions Hydrology for the Nationa/l Floodllnseirance P og m. That report noted:
As discussed in Flood (nsurance Study Guidelines'and Specifrcations for Study,'Contractars" (FEMA
37, January 1995), flood hazard determinauons should be based on conditions thabare planned to
exist in the communiry within 12 months following completion;of~the draft Flood,lsurance Study (FIS) report. Examples of future c nditions to be consiclered'in Yhe context of FEMA'37 are public
works projects in progress, including~cliannel~modificatiis • liydraulic control structures, s[orm-
drainage systems, and o[her flood prot tit\ precta; Thes ar'~ch;nges that will be completed in the
near future for which completion can b6predicted~th,~~a~reasonabl~e~d~egree of certainty and their
completion can be confirmed prior to the NF~IP map becoming effective....
N .
The current procedurc for flood=insurance rahng~s~tfiat~structuresshown within tlie existing
4• r ~t, \ N i Ic ~:1
conditions I-percent-annual-chance;(100-year)flo~odplain are sub~ect to a manda[ory purchase
requirement. Due t stafutory con's[iaints at [his time, FEMA can not use future-conditions data for
flood insurance,purposes Thereforefliere will beoNchange in the use of existing conditions data for
estabhshing~flood`insurancearates:vTh'rough commumty,,participation in the CRS, reduced flood
~ i.. th~ • ~ b 1`-0nP t ~ A
insurance'rates are available for-,ttiose communmesethat enforce more stringent regulatory standards
than~uired by the~NFIP~,[pages 2~.3, 5]
While the SFHA on a FIRM cannot be based on future conditions, local floodplain management
programs are welcome to use future conditions maps, as long as the regulatory floodplain is at
least as large as the currendy effective SPI-IA. In fact, Recommendations for Using Future-
Conditions Flydrolo~ concludes y5ith a recommendation that FIRMs display the future
. 1 Fp .v. .S 3
conditions floodplain for informationa] purposes. This has been done where requested by the
r
community.
The 2008 Biological Opinion stated:
The FEMA will also revise map modeling methods to consider future conditions and the cumulative
effects from future land-use change, to the degree that such information is available (e.g. zoning,
urban growth plans, USGS Climate study infonnation). Future conditions considered should include
changes in the watershed, its floodplain, and its hydrology; climate change, and other conditions that
affect future flood risk. The FEMA shall ensure that jurisdictions use anticipated future land use
changes when conducting hydrologic and hydraulic calculations to determine flood elevations. [page
158]
NFIP-ESA H&H Guidance - 3- January 2010
This section shows how the Biological Opinion requirements can be met within FEMA's current
mapping guidance.
Types of Future Conditions
The term "future conditions" has a number of possible meanings in the context of mapping flood
hazards. From a flood study perspective, there are two general types of changes that can be
expected to occur in the future:
- Changes in the amount of rain and snow that feed floods-(climate change), and
- Changes in the watersheds tbat absorb the rain and snowmelt (land-use changes).
Changes in precipitation: Changes in precipitation dueto climate change are possible. Climate
varies at many timescales, from daily cycles to the.gPacial-intergla\ial pattems that occur over
many thousands of years. Changing climate pattems`can be difficult,to discern because of
significant year to year variation and the short o6se vational record.
Flood studies are necessarily dependent on past
precipitation and flow records, whicti do,not provide ~ / ~Natur6l GrowM Cover - information on flows generated under different dimatic ~ '
conditions. Therefore, existing informatinlis ot clear as fo~
how to alter peak flow predictions to account for< changing~ KeY
climate (see for example,Brekke et al., 2009, Elsn r,et,al~ ~
~ ~ r
2009, Rosenberg et i.~2/ 9)':R~~'"ucther, the gni~ de of~ ° z5% z,%
changes in peak flows due ro changmg climatic condit~ons
is expected to be muchsmaller thankchanges resulting from t+azoxve„eas~N~. - t
alterations to land use, de'scribed below:.Therefore~no
N \ .f' , ~
specific con`iderallonof changes in-peak flow due*to~.
climate cFiange is'iricluded in this guidance`°
~ ~
FEMA is~currently developing,a repoi\.that will assess how 3s-soxaa„oas~~iaea. t
a changing climate will affecf the NFIP\The report will
include estimY s of how climate change uld impact
inland floodplairis and coastlands. The report's findings will 20%is%
N. ~
be incorporated mto future versions of this guidance.
These graphics show the relative
- ~increase in runoff from a watershed
Changes in the watershed: Changes in land use and land as it is urbanized and the amount of
cover (e.g., conversion of forest or agricultural land to urban impervious surfaces increase.
land uses) can have significant impacts on the volume of - NAi roolkit, aSFPnn, 2003
surface water runoff resulting from a given precipitation
event. Changes in land cover typically increase peak flows
by greater than 50 percent in small Puget Sound watersheds, and change the timing of peak flows
(see the graphic, Booth et al., 2002, Grant et al., 2008).
NFIP-ESA FI&H Guidance - 4- January 2010
Forest harvest patterns in managed forest land can also influence runoff patterns. Harvest
patterns include re-growth, so it is assumed that future change from these processes is limited,
since the bulk of these impacts are already accounted for in past flow measurements.
Land-use and land-cover changes in the watershed are anticipated to have the most significant
impacts on peak flows. Therefore, the technical aspects of this guidance are focused on
anticipating and planning for flows generated from a more developed landscape.
Other physical changes in the floodplain include infrastructure changes, such as bridge
replacement, or land use conversion. If such changes are happening or schedu]ed within 12
months of a flood insurance study being undertaken, FEMA.already requires their inclusion in a
new flood study.
Development in the floodplain also has the potential-to r` esulcumulative affects on flood
storage. For example, if the fringe is flled, the base flood elevati n"~ ould rise by up to one foot.
To comply with the Biological Opinion, commi~inities will need to pre e t filling of the
c: "
floodplain or include mitigation measures sucfi,as,compensatory storage so_that man-made
changes in the tloodplain do not affect future flo s In addition>low impact,de elopment
techniques are required for any development allowed within the'4floodplain. Therefore,
development within the floodplain should'not have an mipact on downstream flood peaks.
On the other hand, there could be natural changes i_n~he floodplain that are not necessarily
addressed in Guidelines and Spec~ficati ns\Local`cntical area regulations encourage preserving
the natural and beneti` ial funct~~ion\ of the flo dpla~i~n-Ay ziipar~i~an plant communities develop,
they may provide greater roughnessalong the'channel~banks:and,overbank areas, increasing
flood elevations in those~areas.
Restoration.projects, including,levee,setback pro~ects; have the potential to change flooding
patternsAf an,analy,ss f_nds that thy do ffect'base\flood elevations or the floodway or SFHA
~ ,
boundaries, a CLOMR~from FEIvIA . ~s required~4A:~more projects are completed, they may have
a cumulat ve impact on flood'elevations. However, due to their expense, the few restoration
projects tHat have been complefed cove:rrelatively short reaches. The distribution and effects of
such future projects are difficult to pred ot;: This Regional Guidance does not provide a
mechanism to capture this type~of future condition.
Conclusion: Development in'thJ,watershed has a predictable and measurable impact on the
flow regime. This guidance recommends that communities evaluate changes to the base flood
y
from expected Yuture watershed development based on the development patterns laid out in their
local long range land use plans. At the request of the community, FEMA will reflect the results
of the community-initiated future conditions study on PIRMs when they are revised. The
flooding exten[ determined by future conditions analysis and mapping can be depicted as a
shaded X Zone on the FIRM; instead of the 500-year floodplain.
NFIP-ESA H&f-1 Guidance - 5- January 2010
When to Analyze Future Conditions
There are two situations where it is not necessary to analyze and map future conditions:
L Larger rivers: In general terms, the larger the river system, the less potential impact there
will be from changing land cover (see for example Grant et al., 2008, Herrera, 2004).
These larger systems where future conditions analysis is not required are the "flow
control-exempt" water bodies listed in the Washington State Department of Ecology's
Stormwater Management Munual for Western Washircgton. The list of these waters is in
Appendix 1-E of the Ecology manual and Appendix B ofthis Regional Guidance. The list
should be updated in future versions of the Ecology manual.
2. No change expected: Future conditions do noLn~to be,investigated in areas where the
contributing basin has already been developed a~d thes&conditions are reflected in
existing floodplain mapping. For instancefif the contributing, watershed is in, and is
expected to remain in agriculture or managed forest, these basins do not need to be
analyzed for future conditions.
It is most important ro capture future,conditions for smallerstreams that are located in or near
~ N . \ r y
areas that are likely to urbanize, such as m.or near a city~or rts urban growth area. For smaller
watersheds that are currently undeveloped or only partiallyAe aloped, it is important to
investigate potential changes in peak flows when more than four,percent of the overall watershed
will become effective impervious surface~(Booth etta'5l, 2002) s~general rule, future
conditions hydrology shoald.be determined for all cases wliere over~,ten percent of a stream s
t
contributing basin is c n'verted'from existinggforest.lands or~ha\s`ra,n increase in iuipervious
surface.
-
These criteria-are-summarized:in';Cable 1':
.y Analyze future
Situation conditions
hydrology?
,
Studyis fo \a large, flow control-exempt, water body No
The watershed,is developed up to the levels shown in the land No
use or comprehensive,plan
The watershed is ma aged forest or agriculture with no potential
for conversion No
> 4% of the watershed will become effective impervious surface, Yes
or a>10 % increase is likely if existing condition is >4%
All other situations Yes
Table 1. When to analyze for future conditions
NP1P-ESA H&1I Guidance - 6 - January 2010
Future Conditions Hydrologic Analysis
To develop a reasonable estimate of the future conditions 1 percent annual chance flow, it is
necessary to rely on rainfall runoff simulations with altered land use conditions. Gauge analysis
has the benefit of using measured data, but the data only reflect past land use, not the future.
All of the currently accepted hydrology models for peak flow determination (available at
http://www.fema.gov/plan/prevent/thm/en_hydroshtm) can be used to estimate future conditions
by changing land cover/use parameters. Some models, such as HSPF and SWMM, will be more
amenable to this type of analysis than others. All runoff models,should be calibrated to past flood
events before they are used for base flood determination.
Future land use conditions can be developed using compre" tSensiplans developed by
communities to comply with the Washington Grow[h Management~Act. These plans specify the
type of land uses and, sometimes, percentage of lot coverage allowedydurmg a foreseeable
planning horizon, such as 20 years.
It is recommended that a conservative assumpUon~e2n`sed t~af'all of the area'~in the watershed
will be developed as planned. This information can be.usedin ihe hydrologic model s land use-
to-land cover relationships to describ\e a bui\ld-out condition,ithin the watershed.
\ \i
Stormwater management regulations us :\ually requre,`tormwatermanagement facilities that will
1.
minimize the impact of development oniunoff. The,2005 Ecology manual requires that post-
development flow quantit'ies be managed u§ing flow fr`equencies ranging from 50 percent of the
V
2-year recurrence interval flow to the 50-year recurrence mterval flow.
XX
The influence of stormwater,.management facilities„on the 1 percent annual chance flood is
considered' to be negligible~fomhe follo ing reasons ~
~
-~Thly are required to have overflows suffictient to pass the post-development 100-year
flow, ~
- Th y= anfail due to mcfl-66dc~onditions or deficiencies in design, installation, or
maintenance, 1 ~
- Basic rete tio ,and detention regulations don't address timing, so there's no assurance
that future fl odmg will-not be increased by the facilities, and
N_
- The basic analyhcaF;technique is to ignore all private facilities because of long-tenn
maintenance issues.
Future Conditions Hydraulic Analysis
No changes to the existing hydraulic analyses techniques are necessary to develop future
conditions floodplain mapping based on land use changes as described above. The same models
and approach used for existing conditions can continue to be used with different flows devefoped
in the hydrologic analysis, with the exception of anticipating development of vegetation.
NPIP-ESA H&H Guidance -7- January 2010
Future conditions discharges are input into the hydraulic model to determine the future-
conditions flood hazards. Certain hydraulic parameters may also need to be adjusted based on
expected land-use and land-cover changes, as determined by the communiry.
Vegetation: It is a good floodplain management practice to consider the continuing
establishment of riparian vegetation along channel banks and in the floodplain. This
development could have significant influence on the study's roughness coefficient. For example,
using values from Chow, 1959, a central roughness coefficient (Manning's n) for cultivated land
with no crops is 0.030, and a central value for medium to dense brush in winter is 0.070 (in
Sturm, 2001). The influence of the roughness coefficient on velociry calculations is linear, so
doubling this value will ceRainly inFluence the hydraulic calculatiOns, the resulting base flood
elevation, and the extent of flooding.
Future conditions hydraulic modeling should consider the p/ot ntial~for riparian and floodplain
.
vegetation to establish and continue to develop2herefore, future conditions can assume a full
riparian forest community (e.g., >50 years old},Agricultural areas ca ' be,considered to remain in
production and do not require adjustments. \~t ~
~
Not ali areas will be allowed to develop to full rforesa communiry`has,an operations
and maintenance plan (or similar) that i cludes vegetation'yrriaintenance (e.g., t comply with
PL84-99), then future vegetation development•needs to be14s prescribed in the plan.
Future Conditions Summary
Communities should'analyzc h~ture conditionsfloo h zards*by using the rainfall runoff
models and hydraul c,models descnbed in Guedelines and Specifcations. Future conditions are
generally impacted by changes to thetiand cover conditions. These estimates should be predicted
by local land-use or compeh nsive pla In summary;
• The use of standard,rainfall ninoff models with changed land cover conditions to
simulate future watershed devePopment should be encouraged to predict future peak
fl wsand base flood'elevations~ These estimates should assume full build out as
predicted?by local land'u e,plans.
• Modelers s oul'c] also consider increasing roughness coefficients within the hydraulic
analysis to simulaYe'thecontinued growth of vegetation within the study area.
CRS Credit for Futurc Conditions Ma
PPing
NFI~
The Community Rating System (CRS) is summarized in the separate publication,
CRS Credit for Habitat Protection and explained in more detail in the CRS Coordinator's
Manital. Credit toward reducing flood insurance premiums is provided in communities that
implement floodplain management measures that are above and beyond the minimum require-
ments of die National Flood Insurance Program.
NFIP-ESA H&H Guidance - 8- January 2010
As discussed above, floodplain management regulations using a floodplain map based on future
conditions is above and beyond the guidance in FEMA's Guidelines and Specifccations for Flood
Hazard Mapping Partners. This can be credited by the CRS, provided:
- The hydrologic and hydraulic study techniques used are recognized in Guidelines and
Specifications. A technique that is not discussed there may be submitted to the FEMA
Regional OFfice for consideration for CRS credit.
- The study and floodplain map is adopted for use in the community's development
regulations. New buildings constructed in the regulatory floodplain must be protected to
the future condition's base flood elevation.
- A community may submit the study to FEMA for mcorporation into the next schedu]ed
DFIRM update for that community.
- At each CRS cycle verification visit (generally eve fry ve;years), the community must
document whether its regulatory floodplain data still reflectdfuture conditions. For
example, a study based on a 20-year land use plan prepared in\4995 will no longer reflect
future conditions in 2015.
Regulatory floodplain maps based on-future conditions are credrteder Section
~
411.a "Future conditions hydrology" is defned in the GRSiCoordinator's Manual as changes in
N
watershed land use as discussed in the;previous.pages If another technique is used to reflect
future conditions, an appropriate explanaYion can besubmiti dLr consideration.
~ ~ ~
The amount of credit is based omthe type of FIRM zone and-the amount of the Special Flood
~--l • 1+r1 f•. '4f ~
Hazard Area shown on-the FIRM that is affected by the /newst~y.
<
. ~ :4.
S
NFIP-ESA H&H Guidance - 9- January 2010
Hydraulic Models
Several elements of the Biological Opinion address the selection of appropriate hydraulic
analysis techniques. This section reviews how this can be done.
Current Models
FEMA maintains a list of currently accepted hydraulic models for use in floodplain delineation
on its website at: http://www.fema.gov/plan/prevent/fhm/en_hydrashtm. The currently accepted
hydraulic models for floodplain mapping fall into one of threeigeneral categories: steady one-
dimensional (1 D), unsteady 1 D, or unsteady two-dimensional.(2D). Key features of each type of
model are shown in Table 2. ' y
The imPortance of P- roPer en6ineering Judgment in,deternu" nin tliemost aPProPriate hYdraulic
g
model is underscored throughout Appendix C torCuidelines and Specifzcations. Thisjudgment
should continue to be the primary factor dnvmg m del selection.
Model t:~~
Description Geometry Advantages Disadvantages
TYPe \ 1.'.,,\ \ ' ~1
R
Steady 1D Unchanging flow Cross `section w..Easiest to set;up.and run • Simplifes flow processes
assumed to travel
•,Efficient ''T =A° to 1 D unchan9in9 in time
entirel in the mapping~tool
Y • Does not capture
downstream dire c`tion`
complex overbank flow
~ processes
• Does not address
overbank storage
Unsteady Changing flow (6.g ~ C'ross section : More accureteliming of • Simplifed flow processes
1 D inflow hydrograph)~ ~ ~~l"_'~ p
4eak~especially where to 1 D
"assumed to;travel ,,,multiple sources of water . Requires specifc data
~;e`ntirely in the~down- ~converge input to represent
< stream direciion . Overbank and structure significant water Flux info
~ flows can be simulated and out of overbank
using approximations at storage areas
locations entered by the . Less stable than steady
user models
Takes Floodplain storage . Requires additional data
inlo account development,
hydrographs
Unsteady Changing flow 3D Digital . More realistic simulation of • More data intensive to
and steady assumed to travel elevation complex flow patterns build DEM
2D both downstream and model (DEM) (e.g., strongly meandering . More prone to instability laterally across the streams, overbank flows, , Needs hydrograph for all
channel/floodplain flow compression at bridge major tributaries
piers)
Table 2. General characteristics of the three common types of hydraulic models
NFIP-ESA H&H Guidance - 10 - January 2010
Another consideration Yor the selection of models is the leve( of precision that is required for the
results. In many instances, a less precise hydraulic method will still provide sufficient detail for
mapping floodplains, especially if appropriately conservative assumptions are made during the
modeling and mapping steps.
Regional Guidance
Guidelines and Specifications suggests [he use of steady 1 D models, except when conditions are
too complex for these models to provide satisfactory answers. More complex hydraulic
approaches are used when there is reason ro believe that a steady.l D model will not produce a
reasonable estimate of the base flood elevation. This guidanc canhe found in Section C3.4 of
Guidelines and Specifications.
This Regional Guidance provides more specifc adv-ice`for pl ,different models, but is not
intended to supersede the technical requirements,for applying a specific model provided in the
revised Appendis C to Guidelines and Specifi tions~.
Y` £ ~L, ~ r •if'S + ' ~ M
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A .i s
a ~--~p ~ 5~~~~ ~r.
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2 . . 5'A h. ~
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+ ' r.., ~xC.yc
An unsteady 1D model was used by the Corps of Engineers to develop flood mapping for the Upper
Chehalis River. The Chehalis valley near Chehalis and Centralia is a hydraulically complex area that
includes the confluences of several major tributaries and significant floodplain storage volume. One
product is this map showing flood depths. The use of an unsteady 1 D approach in this location has
additional benefits in terms of supporting the design and analysis of potential flood mitigation
measures.
- NHC
NFIP-ESA H&H Guidance - 1 I- January 2010
Assessing the hydraulic aspects of the channel and floodplain: Several elements of the
Biological Opinion focus on requiring that the NF[P indude measures to avoid, minimize, and
mitigate potential impacts to floodplain storage and physical habitat provided within the channel
and floodplain system. It calls for more complex hydraulic analyses to support the identitication
of impacts and the determination of appropriate mitigation. Unlike steady-state hydraulic
models, unsteady-state models account for floodplain storage. In situations where storage is a
concem, unsteady-state models should be considered. The application of an unsteady 1 D model
will assist in:
- The identification of upstream and downstream impacts-(e.g., stage, velocity, duration) of
floodplain alterations, and
- The development of appropriate and effective mitig~io~nzmeasures.
Some hydraulic systems are best represented by a 246de' 1. Th'\instances include:
- Locations with uncertain and potentially cliangeable flow p
Bridges or other locations where flows experience significant lateral`.fl'ow compression
- Estuaries with flow reversals
~
For example, the use of a 2D model is common for scour analyses at bridge piers and for the
V. \\n, ~`k . ~..1
design of fsh habitat improvement pro)ects4Flow surround~ng;bridge piers has a strong lateral
component which cannot be captured with~a 1 D,a p oach. Similarly, a 2D model will be the
more appropriate choice,to capture post-projeot conditibn{;or habi4tat restoration projects that
include the use of engmeered-log jams to cre\ate moi compiex.flow-processes.
< ~J
CRS Credrt for.HydrauLc Modcling;
NFIP/CRS
~CRS c edit is available for some higher study standards. However, this credit is not
'
provided~wlier" e t"s'standard p aetice to use appropri Ye hydraulic analysis techniques for a
given situ Yion, as speei6ed`in Guidelines and Specrficakons.
NFIP-ESA FI&fi Guidance - 12 - January 2010
Channel Migration Zones
Background
Dynamic physical stream processes can
cause channels to move or "migrate" over ~
time. The area within which a river
channel is likely to move over a period of
time is referred to as the channel migra-
tion zone (CMZ). Channel migration is a
severe hazard that converts normally dry
ground to a river bed, ofren by undercut-
ting and destroying buildings, roads, and
in&astructure. The hydraulic models
approved in Guidelines and Specifica-
tions do not reflect possible changes in zt5
the channel bed during floods.
Keeping inappropriate development out of the CMZ will
prevent flood-related damage such as this. - Packwood,
The NFIP-ESA Model Ordinance uses washington, January 2007 i
the term "channel migration area," wliioh..
is defined as the mapped CMZ plus SO;feet: That is the area ubject to the regulatory
requirements of the ordinance. This R gional Guidance deals~with the hydrologic and hydraulic
aspects of mapping the CMZ Once the CMZ is mappedNthe area subject to regulations can be
quickly delineated
While a CMZ does not`account for dynam~c changes m the channel bed during floods, it does
delineate areas subject Yo'tenhazards The CMZ is not mapped as part of a Flood 1 nsurance Study
v
and is not includedon FIRIVIs; but it.is.appropriatefto-regulate and include within a convnunity's
~ k ~
mappi~g~atabase'
~
BiologicaCOpinion Reqwrements -
Identifying th~tent of the CM'L, is referenced in several parts of the 2008 Biological Opinion:
~N
The FEMA will ensure that effects from habitat alterations that are reasonably certain to occur but
might occur later in tuhe; sugfi as changes in storm water quantity, quality, and treatment, decreased
\ . V- -..:wi
riparian vegetation, lost.large oody debris, increased bank armoring, and impaired channel
N ~
migration, are also mitigated. [page 152]
Bank stabiliza[ion measures along salmonid bearing streams, channel migration zones, and along
estuarine and marine shorelines must be minimized to the maximum extent possible. [page 224]
No activity is allowed that limits the natural meandering pattern of the channel migration zone,
however, natural channel migration patterns may be enhanced or restored [page 224]
The Biological Opinion calls for higher regulatory standards within the Regulatory Floodplain,
which includes the CMZ (page 154). Special rules apply in the Protected Area, which indudes
the channel migration area (CMZ plus 50 feet). FEMA does not require the development of CMZ
NPIP-ESA H&H Guidance - 13 - January 2010
mapping, but if mapping has been completed and adopted for local regulatory purposes before
September 22, 2008, then this designation shall be used to define the channel migration area.
If a community chooses to map and regulate the CMZ, the mapping should be developed
consistent with this Regional Guidance.
Regional Guidance
There are several methods of delineating a CMZ, ranging from approximate to more rigorous
technical methods. 'I'he Washington State Department of Ecoj gy~eleased a CMZ delineation
method in 2003, A Framework for Delineating Channe[ Migration Zones (Rapp and Abbe, 2003)
(referenced here as the 2003 Framework). The 2003 Framewodwas devised to provide a
technical framework for delineating the likely CMZ anv ntended to be implemented by
experienced flwial geomorphologists.
0iologgical ~The 2003 Framework is the method cited in theOpinion as.the,basis for determining
the location of the CMZ. It is also the method recommended for use by thisRegional Guidance.
Key elements of the method are described here, but this discussion is not inten. ded to provide all
of the detail offered in Rapp and Abbe 2003.
The `design life' (how long into the futuRCMZ mapping`,is intended to capture) of the CMZ
mapping is an important consideration that will;infiuence the,applicability and use of the study
for use as the Regulatory Floodplain. T}ietBiologicai Opinion specifies that a 100 year timeframe
be used. This 100 year>hme'f_rame should 6e consideredydifferent y4han the "100-year",
terminology ty pically°psed in flood"plain managerriente'In floodplain terminology "1 QO-year" is
s~sa=-' "..Y
shorthand for an eventvwrth a one percent chance o"f occurring m any given year.
In CMZ delineation, a 100 year design•life.would establish the area the channel could occupy
, \
assuming that-current climatic,conditions and channel,processes continue to occur Por the next
100 years.iThe 100 year design lif.e can be expressed as the potential valley area that the channel
can migrate~within over ] 00 yearslIt,is recognized that the relative hazards of migration can
significanily vary within the ov8ra11 CMZ~\Communities have, and will, implement variable
regulations within,the CMZ.
~
The 2003 Frlmework'identifes`four generalized components of CMZ delineation. This approach
allows for a more detailed,description of physical processes and provides a method to build on
4-
each data collection step. In mosi cases, all of these components will need to be accounted for to
establish a CMZ delineation~: These components are described in Tabie 3 on page 15 and shown
graphically on page 16.
A number of data sources are available to support this work, as shown in Appendix D of Rapp
and Abbe 2003 and Appendix A of this Regional Guidance. The 2003 Framework assumes that
these sources will be used in conjunction with some level of field data collection. 'Chere is a
significant amount of interpretation necessary to accomplish mapping of the various components
of the CMZ. Judgments need to be made about data quality at each step, as the resolution of the
mapping will always be limited by a finite amount of data.
NFIP-ESA H&H Guidance - 14 - January 2010
Element Description Notes Include in the
mapped CMZ?
Historical Migration Zone The collective area the channel Dependent on extent and quality
(HMZ) occupied in the historical record of past records, including ~
Government Land Office maps,
Also referred to as the and past aerial photographs
Yes
Historical Channel
Occupation Tract (HCOT)
see for example
GeoEngineers, 2003
Avulsion Hazard Zone The area not included in the Dependent.on field measure-
(AHZ) HMZ that is at risk of avulsion ments and~idenlification of
over the timeline of the CMZ veAicat chann'el variation, bank
strafigraphy, and the presence Yes
and,location of relict channels
`andiseconiiary flowpaths on the
~floodplain
Erosion Hazard Area The area not induded in the/The EHA can result'f rom either
(EHA) HMZ or the AHZ that is at risk of erosion of the stre`am, bank, or
bank erosion from stream.flow or slope failures of the ban'k'that Yes
mass wasting over the timeline\ occur after erosion of the toe
af the CMZ
Disconnected Migration The portion of:llie,CMZ where ' ,Cere`ineeds lo be taken to ~
Area (DMA) man-made strud'ure`s;such as assess (1) whether the man-
major levees a`nd'Intersiate made;structures will actually
highways, physiczlty elimiriate preve'nt7.hannel movement (e.g.,
channel migrationNtin~some are leveesxsuffciently engi-
cases, a levee prolects,an area,,~ neered?) a`nd2(2) whether the
ihal is~o~important, ihwdl ~ s{ucture highway, or protecled
, wa rr ant:res'toring a mig'raied~ a a•is so'important that there is
~X
channel t`o its~eadier location ~no doulit that after a flood, the Case-by-case
~ channel would be restored to its
previous location. Clear evi-
\Xs dence of lhe presence of a DMA
• \would include: Corps certifed
.levees and a local adopted
maintenance agreement that
t~
k, states that flood fghting would
Noccur and any damage repaired
to prevent channel migration.
,
Table 3. Elements of the overell CMZ (Rapp and Abbe, 2003).
,ax
Note 1- In the case where;there,are features of aquatic habitat existing landward of the levee footprint,
the study should show how the'fiabit t would not be impacted by the selection of the levee as a boundary
to CMZ hazards. ~
The resultant mapping can include a hazard-based treatment of likely CMZ areas. The approach
allows for a ranking of, for example, severe, high, moderate, and low hazard areas throughout the CMZ. This ranking is allowed to be subjective, depending on the mapper's experience and
confidence after working through all of the delineation steps. The use of these designations is
optional and the criteria used to establish them can be determined by each community.
NFIP-ESA H&H Guidance - 1 5- January 2010
While the map should show the 100-year design life channel migration zone, the community
may adopt only the high hazard portion for its channel migration development regulations. For
the purposes of the NFIP-ESA Model Ordinance, the Regulatory Floodplain is based on the
channel migration area, which is the channel migration zone adopted by the community for its
development regulations, plus 50 feet.
CRS Credit for Mapping Channel Migration Zones
Mapping channel migration zones is covered under the CRS credit for uncertain flow
path hazards, found in the Special Hazards Supplement to the GRS Coordinator's Manual. A
stream subject to channel migration is considered a movable,bed stream. A separate supplement
is scheduled to be published in 2010.
Credit points for mapping a CMZ are provided if the eommumty,,also has special development
regulations that protect new development from migrating stream efiannels. The NFIP-ESA
Model Ordinance does not include such regulation`s, as the CMZ is onty;used to help delineate
the Protected Area. Therefore, for CRS credit`th'e communiry must have,ad'ditional CMZ
regulatory standards as well as a map prepared f raccordance with these guidel. ines.
~
FLQW
J ~ ~
B@dFOC{C
40 utcrop EHA
; :
AHZ
!
. • 'KDM~1 `:AHZ - • EHA
- _ ;
_ .
. . .
~ ^ A
'
1930 Active Channel 1950 Active Channel 1960 Active Channel
1970 Active Channel ` 1980 Active Channel 0 1990 Active Channel
2000 Active Channel Historical Migralion Zone • Avulsion Hazard Zon€s
Erosion Hazard Area (Erosion Setback+ Geotechnical Setback)
Oisconnected Migration Area Final CMZ Delinea#ion
Exampie figure of CMZ elements (Rapp and Abbe, 2003)
NFIN-ESA H&H Guidance - 16 - January 2010
The credit for CMZ mapping is provided if the local history of migration is "reflected in the
mapping process. For full credit, mapping must be based upon floodplain soils and historic
channel migration that indicate the probable extent of future migration." (Special Hazards
Supplement, page 30.) Any mapping that implements the 2003 Framework or similarly credible
methods will receive full credit under this element of the CRS.
Half the CMZ mapping credit can be provided when there are no studies that meet the criteria
above. Half credit is provided if a community uses a locally developed standard building setback
for unstudied streams in lieu of a detailed study by a developer. Such a locally developed setback
standard must be based upon data from the general area regulated.
,:'I.iN.•..,
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NFIP-ESA H&FI Guidancc - 17 - January 2010
Appendix A. References
Booth, D.B., D. Hartley, and C. R. Jackson. 2002. "Forest Cover, Impervious-Surface Area, and
the Mitigation of Stormwater Impacts." Journal of the American Water Resources Association.
Vol. 38: 835-845.
Brekke, L.D., Kiang, J.E., Olsen, J.R., Pulwarty, R.S., Raff, D.A., Turnipseed, D.P., Webb,
R.S.S., and White, K.D. 2009. Climate Change and Water Resources Management- A Federal
Perspective. U.S. Geological Survey Circular 1331. http://pubs.ugsg.gov/circ/1331/
Elsner, M.M., Cuo, L., Voisin, N., Deems, J.S., Hamlet, A.F:;~ Vano, J.A., Mickelson, K.E.B.,
Lee, S-Y., and D.P. Lettenmaier. 2009. "Implications of2'ls`Ce tury Climate Change for the
.
Hydrology of Washington State." Washington Climate"~Change lmpacts Assessment Report.
FEMA. 2003. Guidelines and Specifications for Flood Hazard Mapping Partners. Volume 1:
Flood Studies and Mapping. ~\Paithers. FEMA. 2002. Guidelines and Specifications for Flood HazardMapp~ng Appendix C.
Guidance for Riverine Flooding Analyses and Mapping~; ;
FGMA. 2008. Draft Guidelines and Specificattons for Flood Hazard Mapping Partners.
Appendix C. Gziidance for Riverine Flooding An lyses~and Mapping.
S
Federal Emergency Ma ~g m~Y~Agency (FyEMA)!200;•: Mode`rntzing FEMA's Flood /-lazard
Mapping Program: Recommendati ons for Using'Future-CondVOns Hydrology for the Nationa!
Flood Insttrance Program.
~
FEMA. 2007 Nationa\\ d Insiirance P'rogram Community Rating System Coordinator's
Manual1FIA=1'512007i http://www fema g v/li6rary`/viewRecord.do?id=2434
~
FEMA 2006. Special F/azards~Supplement to the CRS Coordinator's Munuul.
http://training fema.gov/em web/CRS%index.htm
4:e
\ , ~
FEMA, 2010, CRSCredit for Habitat Protection, http://training.fema.gov/EMIWeb/CRS/
FEMA 2010. Mode[ Or dinance for Floodp/ain Management Under the National Flood
lnsurance Prograrn and tli'e, Endangered Species Act
GeoEngineers, 2003. "Geomorphic Evaluation and Channel Migration Lone Analysis Puyallup,
Carbon, and White Rivers." Prepared for Pierce County Public Worka and Utilities
Environmental Services, Water Progams Division. June 19, 2003.
Grant, G.E., Lewis, S.L., Swanson, F.J., Cissel, J.H., McDonnell, J.J. 2008. G/(ects o/rorest
Practices on Peak Flows and Consequent Channel Response: A State-of-Science Report for
Westet-n Oregon and Wushington. Gen. Tech. Rep. PNW.GTR-760, Portland, OR: U.S.
Department of Agriculture, Forest Service, Pacific Northwest Research Station.
NFIP-GSA FI&FI Guidance A- 1 January 2010
1
Herrera Environmental Consultants, Inc. Northwest Hydraulic Consultants, 2004. "Discharge of
Stormwater to High Order Streams: Determining Exempt Reaches." Prepared for Washington
State Department of Transportation. April 13, 2004.
Mote, P., Petersen, A., Reeder, S., Shipman, H., and L. W. Binder. 2008. Sea Level Rise in the
Coastal Waters of YVashington State. University of Washington Climate Impacts Group and the
Washington State Department of Ecology. January 2008.
NMFS (National Marine Fisheries Service). 2008. Endangered Species Act - Section 7
Consultation Final Biological Opinion and Magnuson-Stevens ~~chery Conservation and
Management Act Essential Fish Habitat Consultation. Implemenfation of the National Flood
Insurance Prograrri in the State of Washington Phase Ona Doc ent - Puget Sound Region.
September 22, 2008. ~ . ~
Rapp, C.F and T.B. Abbe. 2003. A FrameworkforDneating chdnnel migration zones.
Ecology Final Draft Publication #03-06-027 hitp:(/www.ecy.wa.govlio/0306027.htm1
Rosenberg, E.A., Keys, P.W., Booth D.B. Hartl D, Burkey; J, Steinema n, A.C., and
y~"R~^`
Lettenmaier, D.P. 2009. Precipitataon Extremes ante Impacts of Climate Change on
~
Stormwater Infrastructure in WashangtorirS,tate. Implication,s~of 21 s~ century climate change for
the hydrology of Washington State Washington Climate Change Impacts Assessment Report.
March 2009. n\mz~
Sturm; T.W. 2001. Open~Gh`~r~n_n'el` Hydraukcs~ McGraw H~I1,,New~+York, NY.
fil
Washington State Department of Ecology 200N4~ Sto"rmwater Management Manual for Eastern Washzngton Publicati ner 04 310 076
"z-~- "~~~~~~~.t *~~~,a. ~s
Washingt'on`,State D p rtmenY of Ecology`2005'* Storin;water Management Manual for YVestern
Washa~ngton. PublicationzNumbers OS 10-029 through 05-10-033.
~
~4W
>
NFIP-ESA H&H Guidance A- 2 January 2010
Appendix B. Flow Control-Exempt Surface Waters
(Appendix I-E to Stormwater Management Manual for Western Washington)
Stormwater discharges that are otherwise subject to Minimum Requirement 47 - Flow Control,
to waters on this list must meet the following restrictions to be exempt from Minimum
Requirement #7. - Direct discharge to the exempt receiving water does not result in the diversion of
drainage from any perennial stream classified as Types6l;,2, 3, or 4 in the State of
Washington Interim Water Typing System, or Typess"S"; or "Np" in the Permanent
Water Typing System, or from any category I, II,F r"III~wetland; and
- Flow splitting devices or drainage BMP's are*applied to route natural runoff volumes
from the project site to any downstream Type>5 stream or category IV wetland:
~ ~
- Design of flow splitting devices or drainage BMP's will be based9on continuous
hydrologic modeling analysis. The design will ass e that flows~deliuered to Type 5
~ ,~"~w'
stream reaches will approximate but in no~+ casejexceed, durations ranging from 50%
of the 2-year to the 50 y aWpeak flow.
- Flow splitting devices or dramage BIvIP's,that deliver~flow to category IV wetlands
'~r°~ •
will also be designed usmg continuous hydrologic modelmg to preserve pre-project
wetland hydrologic,~conditions unless spe cif cally,t d or exempted by regulatory
agencies with'permiftmgajurisdicti6n,4and~
~ N
~n, ; ~ N
- The project site must=be dramed by a conveyance system that is comprised entirely of
~
mamriade°conveyan 'ce~,ele~rments~(eg„pipes~t,-ditches, outfall protection, etc.) and extends
to the=ordmarya;.hlgh water ]me of the exempt receiving water; and
se
0 ~ a C N
- The'conveyance systein betwe~~en, he project site and the exempt receiving water shall
have~anhydraulic capaoity, sufficientato convey discharges from future build-out
condition°s~(under curreiit:zoning) of the site, and the existing condition from non-project
areas from which runoffjs'or will be collected; and
- Any erodible elements,4f,the manmade conveyance system must be adequately stabilized
to prevent erosiori underythe conditions noted above.
NFIP-ESA H&H Guidance B- 1 January 2010
Exempt Surface Waters List
Alder Lake
Aston Creek Downstream of confluencewith George Creek
Baker Lake
Baker River Baker River/Baker Lake downstream of the confluence with Noisy
Creek
Bogachiel River 0.4 miles downstream of Dowans Creek
Calawah River Downstream of confluence with South Fork Calawah River
Carbon River pownstream of confluence with Sou\di Prairie Creek
Cascade River Downstream of Found Creek
Cedar River Downstream of confluence with Taylor Creek
Chehalis River 1,500 feet downstream ofconfluence with Stowe Creek
Chehalis River, South Fork 1,000 feet upstream of coiiflu n e4rth Lake Creek
Cispus River pownsVeam of conflii nce wi[h Ca[ Greek
Clearwater River pownstream of~c nflue ce with Chris[ na~eek
Columbia River pownstream of Ca adian border
Coweman River pownstream of coiifluence with Gobble Creek
Cowlitz River Downstream of conFluence of~Ohanapecosh Ri~nafid Clear Fork
tCowlitz River
Crescent Lake ~ -
Dickey River pownsh a\nfl\ nce with C\I Creek
Dosewa l lips River powns[ream o f con fluence wit t i Roc ky Brook
Dungeness River Downstream of confl ence with Gray,Wolf River
' Elwha River DownsVeam~ot conflence w~i Gold e River
Grays River Downstream of~o fluence withIHull Creek
Green River (WRIA 26-.Cowlrtz) ~'3.5 miles upstream of Devils Creek Hoh Rrver ~1 2 nules-downstream~of Jackson Creek
Humptuhps+River Down`Stream qf.conFlu nce with West and East Forks
KalamaRfver``' 2:0'milesdownstr~ea~n~ofJacksCreek
E_' ~N s
Lake Cushman ~
Lake Qui iault
Lake ShannotS
LakeSammam~i~stN,.,
Lake Union & Unioir$ay Ki,itg County
Lake Washington, Ship"Clinal & Salinon Bay
Lake Whatcom ~y
Lewis River ~Downstream of conFluence wi[h Quartz Creek
Lewis River, East Fork Downstream of confluence with Big Tree Creek
Lightning Creek DownsVeam of confluence with Three Fools Creek
Little White Salmon River pownstream of confluence with Lava Creek
Mayfield Lake
Muddy River pownstream of confluence with Clear Creek
Naselle River pownstream ofconFluence widi Johnson Creek
Newaukum River pownstream of confluence with South Fork Newaukum River
Nisqually River pownstream of conFluence with Big Creek
Nooksack River pownstream of confluence of North Fork and Middle Forks
NFIP-ESA H&H Guidance B- 2 January 2010
Nooksack River, North Fork Downstream of conFluence with Glacier Creek, at USGS gauge
12205000
Nooksack River, South Fork 0.1 miles upstream of confluence with Skookum Creek
North River pownstream of confluence with Vesta Creek
Ohanapecosh River powns[ream of confluence with Summit Creek
Puyallup River Flalf-mile downstream of confluence with Kellog Creek
Queets River pownstream of confluence with Tshletshy Creek
Quillayute River pownsVeam of Bogachiel River
Quinault River pownstream of conFluence with North Fork Quinault River
Riffe Lake
Ruby Creek Ruby Creek at SR-20 crossing dow stream of Granite and Canyon
Creeks / j
Satsop River pownstream of confluence of Middle and Eas[ Forks
Satsop River, East Fork Downstream of confluence Wrth Decker Creek
Sauk River pownstream of confl nce of South Fork and North Fork
Sauk River, North Fork North Fork Sauk'Ri'ver at Bedal Campground
Silver Lake Cowlitz County,~ ~
Skagit River pownstream of Canadian border,
Skokomish River pownstream of conFluence of Nortli and South Fork .
Skokomish River, South Fork Downstiream of conFluence th~Vance Creek
Skokomish River, North Fork Do nstream of confluence~with McTaggert Creek ~
\ \
Skookumchuck River I mile upstream of Bucoda aT SR 507 mile post 11.0
Skykomish River pownstream of South Fork
Skykomisli River, South Fork `~Downstream of confluei i e of Tye and Foss Rivers
Snohomish River pown stream of;confluencerot Sno,gualmie and Skykomish Rivers '
Snoqualmie River ' Downstream of onfluece ofthe,Middle Fork
Snoquahnie River, Middle Fo o nstream of confluence with Rainy Creek
Sol Duc Rrver~ Do nstream ofconfluence ofNorth and South Fork Soleduck River
Stillaguamish";R~ver"?,, Downstream of conFluence of North and South Fork
,,e I ~ I
Stillaguamuh~Rrver, North`Fork 7:7•highway mtles weshof Darrington on SR 530, downstream of
~K ~ on\ucnce wrth E'rench Creek.
Stillaguamish~ltiver, South Fork , Downstream of confluence of Ganberry Creek and South Fork
~
Suiattle Ri er Downs~ream.ofconfluence with Milk Creek
Sultan River 0A miles upstream of SR2
Swift Creek Reservoir..
Thunder Creek Downstream of the conFluence with Neve Creek
Tilton River Downstream of confluence with Nor[h Fork Tilton River
Toutle River North and South Fork ConFluence
"foutle River, North Fork Downstream of conFluence with t-loffstadt Creek
Toutle River, South Fork Downs[ream of conFluence with Thirteen Creek
White River pownstream of conFluence with Huckleberry Creek
Willapa River pownstream ofconFlucnce with Mill Creek
Wind River pownstream of confluence with Cold Creek
Wynoochee Lake
Wynoochee River pownstream ofconfluence with SchaferCreek
NFIP-ESA H&fi Guidance I3 - 3 January 2010
Draft
City of Auburn
Regulatory Floodplain
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Regulatory Floodplain: The Regulatory Floodplain is composed ' ='e~ ~
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of the Special Flood Hazard Area and the Protected Area as y,. ~ ~ y~',' 7~ " ~t 4~k~, t~"!
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FEMA 100 Year Floodplain ~ ll , ;~~`rv, "~.w ~ ~ ~ Y~ ,T~~~, ~y` 'y rMl ,I ~~t. w-!~ . ~
: r. ,.~i ~ . r~ I ~f ♦ i" r 4t ~a •
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Protected Areas `.d~T ~.:t. ' ~f 'r ,"~~?~r, ~9 ^ ~~y~ ~7 •~~.~f "~a, - ' „F ` j~~,~ ~ , ~t ~ ~ ~
~ FloodWfly ~i.:~ ~~'srK-'4~~'~~,~•i~"?3 ' ~ ; i ~y;~'I~~?x~ri~.`.~ ~ :u °'r ,r'•7 ~ ~,y{,.•-, } Y 3~k.
~ x l i. ; ,~T y~, ' - M, 1 ~ M~ ~ f~N ` ~ j, + . ,d1t~ ,s: r . ~ KZ .
Riparian Habitat Zone (RHZ) ~ ~ r ~ f a' "p~3 ~ ,J~ ~~c'.s`"v~
r - 1{ ~ r {I j ~ ~ ~ ~ M 1 lr' ~ r .C~ S ' ~ .C ~ e~*ti~. . r w'k,'J. ~ y1. ~ , , -11 PI.I. -j.. ~ ~ _ b! .~u f„r 4r ~L`. ti. ~x
ChannelMigrationArea (CMA) - ~ t 1 } ,"c" ~ i:~ 4„-i Gp,`~: z'~~t f1N r~S,~ yu~b v~Ya r
¢ 1~ Z ~f.. .+.w.~., . i a i ri • t: • p+ _ '~•~,i 3', ' ',~y '
. ~ 7 IM~ 1.•..*a-~.~ i ~ . ~ ~ , t C ,',r;y- yr
~ ~ "r `r`.. ~ ' l~ . I . ~ti~.~ l~. , t 't '.T'
Disclaimer: ~ '11'ti 4 ~_~,4 u ip I ~ } . i 3 t J~l**~• .i -~-~7 y ~ t ~ ~l 175111 R
".taps generally depicl regula[ory (toodplain boundarics in Ihe City a ~ ~ ti ~ '4 ~ ~'t~F~?~ ~ ,R,,.~ ~ . ~J - ~ ~ . +R~:~ ~i ~ . ~i i ~ ~ ,~y
of auburn. All 6oundaries arc approxima[e and are sub)ec[ R ~ - vw!' j~ ~ eaF j ~ . ~ a.~
m change wtith additionat daW. Maps do not incWde critical areas ' i, = ~ L' ~ ~ f, . . ~'~Y-~'` tr~} i ~ . F' ' tr.~ ,I~ ~ ~ ~ , *
or shorelinc da[a. Please note (or mapping and referencc purposes ~ 7: i - t~' ~ ~ ° ` - . Y% '
: ,aylt..- . - .ca...~ . ~ ~C. - } _L . vFj . ~ r { ~x ,f r -C a
iome daYa is shown beyond Auburn City Limlts; however, T _ ~ y~ ~ ~ i a~ `.r ,1 j ~ ,-ti i~ ~ 1~^_24~ -i,1~, ~ _ y q~ - 1 _
Gry ot Auburn Rcautatory Ffoodplain does no[ extend eo - t ; , -y. ~ ^„4 . :r ,ti; - ~ 4X,~w e°' ~ . .
areas outside the City. In(ormation shown is (or gene~a. ~ ;`,`J' '+t~~ + " ~ ,.a, ~ ~ ~ -r.w, . ~ <-e " `T' ~dy~
~e.~ w
rf4 jk , ,aw'~ .y,~ %h ^
~'eferen[c purposes onry and does not necessarily rcpresent ' . ~ ? ' ~~!~1 ~ - .'j ~i ~ 1 : iiCT.'~ ~'~v ~-,r ,
exact geographi[ or car[ographic data as mapped. . ' ~ ~ _ ~4 t.,~ ~ ~ . ,o- ` . y r ~ r ~r,~ 7, - i t '
be determined by Gty of Auburn Ordinance #6295, 3. r ~ :r ~ ~ ~ tl
~ ,c y~
~ ~ il
assocated City Code sections, and FEMA guidance documents. : a; ~ ~ . ~ ~ . ~t}„ t ,i~ t~ ~,A_5 ` .,~'j. ~ v_ , s
~ - ~ . r
DataSaurce: ~;ifq : ~ f~ . • -
1. FENJ. 100 Year Fioodptain and Floodway: FEMA Flood Insurance Rate Maps (19E' " w~ a - . ; V r""4~i: . . . . x ~ ~
Picrce County. 1995 King County) , ~ a t r. ~ ~ a+. ~ ~ j 1 ' ~ ~ ~ ~
2. Ripanan Habitat Zone: City o(Aubum OrdinanceN6295 i20101 N i~°+K'- - z.~.~J> ~~'o . ~ ~ _;r.~• ~ -
3. Channel Miaration Arca: King County Green River ~ S "1~ fi t~~. ~ ~t~' .1 ~ . ~ '~or - ry~~ ~ '/?Y - . r } _
Channel Migration Zone SWdy 11997! and City of Auburn S~`_ ~ t,~ •ft,~. y,'~., `li 1.^'s." ; . _
Ordinance46295120101 w ~ ~ ~ ,ti«..l:tH e. T3~ . C. 1~. `i~;?• k ~+ti~" .--.a._• ,a s..~+ ~'~3^.
U SCO 1,600 Z.400 3.260 4,000 I-' ~ ~ ~r . ~ ~ ~ ~ , 1~a'' a i. n A I 3 . ~ . .
Printed On "u2..... 70 _ z1 I-.A1F'~. ~*~..S'`~ .,~.r~~~ 4 + tiY' 2 _
~=P ~D. 3a3' FEET . H M1 A - _ _