HomeMy WebLinkAboutReg 2020-11-16 Item 4F - Ordinance - Flood Plain ManagementCOUNCIL AGENDA SYNOPSIS
---------------------------------- Initials
Meeting Date
Prepared by M or 's review Council review
11/09/20
GL
11/16/20
GL
❑ Resolution
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®Ovdinance
Mtg Date 11/16/20
❑BidAavavd
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❑ Publz'c Heating
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ITEM INFORMATION
ITEMNO.
4. F.
, V.
STAFF SPONSOR: RYAN LARSON
ORIGINAL AGENDA DATE: 11/09/20
AGENDA ITEM TITLE Flood Plain Management Ordinance
CATEGORY ®Discussion
Mtg Date 11/09/20
❑Motion
Mtg Date
❑ Resolution
Mtg Date
®Ovdinance
Mtg Date 11/16/20
❑BidAavavd
Mtg Date
❑ Publz'c Heating
Mtg Date
❑ Other
Mtg Date
SPONSOR ❑Council ❑Mayor ❑HR ❑DCD ❑Finance ❑Fiore OTS ❑P&R ❑Po&e ®PWI ❑Court
SPONSOR'S The Federal Emergency Management Agency notified all Washington jurisdictions
SUMMARY participating in the National Flood Insurance Program (NFIP) that our Flood Ordinance
would require updates to comply with new federal and state regulations and to adopt
revised Flood Insurance Rate Maps (FIRMS). On 8/17/20, Council approved an Interim
Flood Plain Mgmt Ordinance. All reviews have now been completed with no changes to the
Ordinance. Council is being asked to approve the final Flood Plain Management Ordinance.
REVIEWED BY ® Trans&Infrastructure ❑ CommunitySvs/Safety ❑ Finance Comm. ❑ Planning/Economic Dev.
❑ LTAC ❑ Arts Comm. ❑ Parks Comm. ❑ Planning Comm.
DATE: 07/20/20 & 08/03/20 COMMITTEE CHAIR: C. DELOSTRINOS JOHNSON
RECOMMENDATIONS:
SPONSOR/ADMIN. Public Works Department
COMMITTEE Unanimous Approval; Forward to Committee of the Whole
COST IMPACT / FUND SOURCE
EXPENDITURE REQUIRED AMOUNT BUDGETED APPROPRIATION REQUIRED
$0.00 $0.00 $0.00
Fund Source:
Comments.
MTG.DATEI
RECORD OF COUNCIL ACTION
11/09/20
Forward to next Regular Meeting Consent Agenda
11/16/20
MTG. DATE
ATTACHMENTS
11/09/20
Informational Memorandum dated 07/17/20 (revised 11/6/20 for final adoption)
Draft Flood Plain Ordinance (revised after 7/20 T&I Committee)
Minutes from Transportation and Infrastructure Committee meeting of 7/20 & 08/03/20
11/16/20
Ordinance
, V.
50
Cl*ty
um of Tulcwi'l
Washington
AN ORDINANCE OF THE CITY COUNCIL OF THE CITY OF
TUKWILA, WASHINGTON, REPEALING ORDINANCE NO.
2633, INTERIM FLOOD PLAIN MANAGEMENT REGULATIONS
(TUKWILA MUNICIPAL CODE (TMC) CHAPTER 16.52);
REENACTING TMC CHAPTER 16.52 TO UPDATE FLOOD
PLAIN MANAGEMENT REGULATIONS AND POLICIES AS
REQUIRED OF JURISDICTIONS PARTICIPATING IN THE
NATIONAL FLOOD INSURANCE PROGRAM; PROVIDING FOR
SEVERABILITY; AND ESTABLISHING AN EFFECTIVE DATE.
WHEREAS, flood hazard areas in Tukwila are subjectto periodic inundation which
may result in loss of life or property, may create health or safety hazards, may disrupt
commerce or governmental services, may cause extraordinary public expenditures for
flood protection and relief, or might impair the tax base, all of which adversely affect the
public health, safety, and general welfare; and
WHEREAS, these flood losses may be caused by the cumulative effect of
obstructions in areas of special flood hazards that increase flood heights and velocities,
and damage uses in other areas when inadequately anchored; and
WHEREAS, uses that are inadequately flood -proofed, elevated or otherwise
protected from flood damage can contribute to losses due to flooding; and
WHEREAS, the Legislature of the State of Washington delegated the responsibility
to local governmental units of adopting regulations designed to promote the public
health, safety, and general welfare of its citizenry; and
WHEREAS, in Title 86 of the Revised Code of Washington, the Legislature of the
State of Washington authorized local governmental agencies to regulate use and
development of flood hazard areas within their jurisdictions in order to reduce such
hazards; and
WHEREAS, continued participation by the City of Tukwila in the National Flood
Insurance Program requires adoption of flood plain management standards and a
floodplain construction permit process; and
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WHEREAS, on July 27, 2020, the Tukwila City Council, following adequate public
notice, held a public hearing to receive testimony on the proposed ordinance; and
WHEREAS, review by the Washington State Department of Commerce, as well as
a SEPA (State Environmental Policy Act) comment and appeal period and final
determination, were required prior to adoption of final flood plain management
regulations, and were not expected to be complete prior to the FEMA deadline for
adoption of updated flood plain management regulations; and
WHEREAS, on July 24, 2020, the Department of Commerce notified the City of
Tukwila that it had met the Growth Management notice to state agency requirements in
RCW 36.70A.106 on the flood plain management regulations; and
WHEREAS, on August 17, 2020, the Tukwila City Council adopted Ordinance No.
2633, which implemented interimflood plain management regulations; and
WHEREAS, on August 18, 2020, the City of Tukwila issued a Determination of
Non -Significance (DNS) on the flood plain management regulations; and
WHEREAS, on August24, 2020, the Tukwila City Council held a public hearing on
the interim ordinance forflood plain management regulations, including Findings of Fact
and/or Conclusions, as required within 60 days of the adoption of the interim ordinance;
NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF TUKWILA,
WASHINGTON, HEREBY ORDAINS AS FOLLOWS:
Section 1. Repealer. Ordinance No. 2633, "Interim Flood Plain Management
Regulations" (Tukwila Municipal Code (TMC) Chapter 16.52, "Flood Plain
Management,") is hereby repealed.
Section 2. TMC Chapter 16.52 Reenacted. TMC Chapter 16.52 is hereby re-
enacted to read as follows:
CHAPTER 16.52
FLOOD PLAIN MANAGEMENT
Sections:
Interpretation
16.52.010
Statutory Authorization
16.52.020
Purpose
16.52.030
Definitions
16.52.040
Applicability
16.52.050
Basis for Establishing the Areas of Special Flood Hazard
16.52.0 60
Interpretation
16.52.070
Warning and Disclaimerof Liability
16.52.080
Administration
16.52.090
Permits
16.52.100
Standards
16.52.110
Floodways
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16.52.120
Critical Facility
16.52.125
Compliance
16.52.130
Penalties
16.52.140
Abrogation and Greater Restrictions
Section 3. TMC Section 16.52.010 is hereby reenacted to read as follows:
16.52.010 Statutory Authorization
The Legislature of the State of Washington delegated the responsibility to the City
of Tukwila to adopt regulations designed to promote the public health, safety, and
general welfare of its citizenry.
Section 4. TMC Section 16.52.020 is hereby reenacted to read as follows:
16.52.020 Purpose
This chapter aims 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 to:
1. Protect human life and health;
2. Minimize expenditure of public money and costly flood control projects;
3. Minimize the need for rescue and relief efforts associated with flooding and
generally undertaken atthe expense of the general public;
4. Minimize prolonged business interruptions;
5. 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;
6. Help maintain a stable tax base by providing for the sound use and
developmentof areas of special flood hazard so as to minimize future flood blight areas;
7. Ensure that potential buyers are notified that property is in an area of
special flood hazard;
8. Ensure that those who occupy the areas of special flood hazard assume
responsibility for their actions; and
9. Participate in and maintain eligibility forflood insurance and disasterrelief.
Section 5. TMC Section 16.52.030 is hereby reenacted to read as follows:
16.52.030 Definitions
Unless specifically defined below, words or phrases used in this chapter shall be
interpreted to give them the meaning they have in common usage and to give this
chapter its most reasonable application.
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1. Alteration of watercourse: Any action that will change the location of the
channel occupied by water within the banks of any portion of a riverinewaterbody.
2. Appeal: A request for a review of the interpretation of any provision of this
chapter or a request for a variance.
3. Area of shallow flooding: A designated zone AO, AH, AR/AO or AR/AH
(or VO) on a community's Flood Insurance Rate Map (FIRM) with a one percent or
greater annual chance of flooding to an average depth of one to three feet where a
clearly defined channel does notexist, where the path of flooding is unpredictable, and
where velocity flow may be evident. Such flooding is characterized by ponding orsh eet
flow. Also referred to as the sheetfIow area.
4. Area of special flood hazard: The land in the floodplain within a
community subject to a 1 percent or greater chance of flooding in any given year. It is
shown on the Flood Insurance Rate Map (FIRM) as zone A, AO, AH, Al -30, AE, A99,
AR (V, VO, V1-30, VE). "Special flood hazard area" is synonymous in meaning with the
phrase "area of special flood hazard".
5. ASCE 24: The most recently published version of ASCE 24, "Flood
Resistant Design and Construction", published by the American Society of Civil
Engineers.
6. Base flood: The flood having a 1% chance of being equaled or exceeded
in any given year (also referred to as the "100 -year flood").
7. Base Flood Elevation (BFE): The elevation to which floodwater is
anticipated to rise during the base flood.
8. Basement: Any area of the building having its floor sub -grade (below
ground level)on all sides.
9. Building: See "Structure."
10. Building Code: The current editions of the building codes and
amendments adopted by Washington State and amended by the City of Tukwila.
11. Breakaway wall: A wall that is not part of the structural support of the
building and is intended through its design and construction to collapse under specific
lateral loading forces, withoutcausing damage to the elevated portion of the building or
supporting foundation system.
12. Critical facility: A facility for which even a slight chance of flooding might
be too great. Critical facilities include, but are not limited to, schools; nursing homes;
hospitals; police, fire and emergency response installations; and installations that
produce, use, or store hazardous materials or hazardous waste.
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13. Development: 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 or storage of equipment or
materials located within the area of special flood hazard.
14. Director: The Director of Public Works or designee.
15. Elevation Certificate: An administrative tool of the National Flood
Insurance Program (NFIP) that can be used to provide elevation information, to
determine the proper insurance premium rate and to support a request for a Letter of
Map Amendment(LOMA) or Letter of Map Revision based on fill (LOMR-F).
16. Elevated building: For insurance purposes, a non -basement building that
has its lowest elevated floorraised above ground level by foundation walls, shearwalls,
post, piers, pilings, or columns.
17. Essential facility: This term has the same meaning as "Essential Facility"
defined in ASCE 24. Table 1-1 in ASCE 24-14 further identifies building occupancies
that are essential facilities.
18. Flood or Flooding:
(a) A general and temporary condition of partial or complete inundation of
normally dry land areas from:
(1) The overflow of inland ortidal waters;
(2) The unusual and rapid accumulation or runoff of surface waters
from any source; and/or
(3) Mudslides (i.e., mudflows), which are proximately caused by
flooding as defined in subparagraph (a)(2) of this definition and are akin to a river of
liquid and flowing mud on the surfaces of normally dry land areas, as when earth is
carried by a currentof water and deposited along the path of the current.
(b) The collapse or subsidence of land along the shore of a lake or other
body of water as a result of erosion or undermining caused by waves or currents of
water exceeding anticipated cyclical levels or suddenly caused by an unusually high
water level in a natural body of water, accompanied by a severe storm, or by an
unanticipated force of nature, such asflash flood or an abnormal tidal surge, or by some
similarly unusual and unforeseeable event that results in flooding as defined in
subparagraph (a)(1) of th is defin ition.
19. Flood elevation study: An examination, evaluation, and determination of
flood hazards and, if appropriate, corresponding water surface elevations, or an
examination, evaluation and determination of mudslide (i.e., mudflow) and/or flood -
related erosion hazards. Also known as a Flood Insurance Study (FIS).
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20. Flood Insurance Rate Map (FIRM): The official map of a community on
which the Federal Insurance Administrator has delineated both the special flood hazard
areas and the risk premium zones applicable to the community. A FIRM that has been
made available digitally is called a Digital Flood Insurance Rate Map (DFIRM).
21. Floodplain or flood -prone area: Any land area susceptible to being
inundated bywater from any source. See "Flood or Flooding."
22. Floodplain Administrator: The community official designated by title to
administerand enforcethe floodplain management regulations.
23. Floodplain management regulations: Zoning ordinances, subdivision
regulations, building codes, health regulations, special purpose ordinances (such as
floodplain ordinance, grading ordinance and erosion control ordinance) and other
application of police power. The term describes such state or local regulations, in any
combination thereof, that provide standards for the purpose of flood damage prevention
and reduction.
24. Flood proofing: Any combination of structural and nonstructural
additions, changes, or adjustments to structures that reduce or eliminate risk of flood
damage to real estate or improved real property, water and sanitary facilities, structures,
and their contents. Flood -proofed structures are those that have the structural integrity
and design to be impervious to floodwater below the Base Flood Elevation.
25. Floodway: The channel of a river 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 a designated height.
Also referred to as "Regulatory Floodway."
26. Functionally dependent use: A use that cannot perform its intended
purpose unless it is located or carried out in close proximity to water. The term includes
only docking facilities, port facilities that are necessary for the loading and unloading of
cargo or passengers, and ship building and ship repair facilities, and does not include
long-term storage or related manufacturing facilities.
27. Highest adjacent grade: The highest natural elevation of the ground
surface prior to construction nextto the proposed walls of a structure.
28. Historic structure: Anystructure that is:
a. Listed individually in the National Register of Historic Places (a listing
maintained by the Department of the Interior) or preliminarily determined by the
Secretary of the Interior as meeting the requirements for individual listing on the
National Register;
b. Certified or preliminarily determined by the Secretary of the Interior as
contributing to the historical significance of a registered historic district or a district
preliminarily determined by the Secretary to qualify as a registered historic district;
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c. Individually listed on a state inventory of historic places in states with
historic preservation programs that have been approved by the Secretary of the
Interior; or
d. Individually listed on a local inventory of historic places in communities
with historic preservation programs that have been certified either:
the Interior, or
(1) By an approved state program as determined by the Secretary of
(2) Directly by the Secretary of the Interior in states without approved
programs.
29. Lowest floor: The lowest floor of the lowest enclosed area (including
basement). 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, provided that such enclosure is not built so as to
render the structure in violation of the applicable non -elevation design requirements of
this chapter (i.e. provided there are adequate flood ventilation openings).
30. Manufactured home: A structure, transportable in one or more sections,
that is builton a permanent chassis and is designed for use with or withouta permanent
foundation when attached to the required utilities. The term "manufactured home" does
not include a "recreational vehicle."
31. Manufactured home park or subdivision: A parcel (or contiguous
parcels) of land divided into two or more manufactured home lots for rent or sale.
32. Mean sea level: For purposes of the National Flood Insurance Program,
the vertical datum to which Base Flood Elevations shown on a community's Flood
Insurance Rate Map are referenced.
33. New construction: For the purposes of determining insurance rates,
structures for which the "start of construction" commenced on or after the effective date
of an initial Flood Insurance Rate Map or after December 31, 1974, whichever is later,
and includes any subsequent improvements to such structures. For floodplain
management purposes, "new construction" means structures for which the "start of
construction" commenced on or after the effective date of a floodplain management
regulation adopted by a community and includes any subsequent improvements to such
stru ctu res.
34."NFIP" means National Flood Insurance Program.
35. One -hundred -year flood or 100 -year flood: See "Base flood."
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36. Reasonably safe from flooding: Development that is designed and built
to be safe from flooding based on consideration of current flood elevation studies,
historical data, high water marks and other reliable data known to the community. In
unnumbered"A" zones where flood elevation information is notavailable and cannot be
obtained by practicable means, "reasonably safe from flooding" means the lowest floor
is at least two feet above the Highest Adjacent Grade.
37. Recreational vehicle: A vehicle:
a. Builton a single chassis;
b. 400 square feet or less when measured at the largest horizontal
projection;
c. Designed to be self-propelled or permanently towable by a light-duty
truck; and
d. Designed primarily not for use as a permanent dwelling but as
temporary living quarters for recreational, camping, travel, or seasonal use.
38. Special Flood Hazard Area (SFHA): The land in the flood plain subject to
a 1% or greater chance of flooding in any given year. It is also referred to as the 100 -
year flood elevation or the base flood elevation. These areas are designated on Flood
Insurance Rate Maps (FIRMs) using the letters A or V. Special flood hazard areas
include flood -prone areas designated by the City.
39. Start of construction: Includes substantial improvement and means the
date the building permit was issued, provided the actual start of construction, repair,
reconstruction, rehabilitation, addition, placement, or other improvement was within 180
days from the date of the permit. The actual start means either the first placement of
permanent construction of a structure on a site, such as the pouring of slab orfootings,
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/orwalkways; nor does it include excavation
for a basement, footings, piers, or foundations 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 meansthefirst 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.
40. Structure: For floodplain management purposes, a walled and roofed
building, including a gas or liquid storage tank, that is principally above ground, as well
as a manufactured home.
41. Substantial Damage: Damage of any origin sustained by a structure
wherebythe cost of restoring the structureto its before -damaged condition would equal
or exceed 50 percent of the market value of the structure before the damage occurred.
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42. Substantial improvement: Any reconstruction, rehabilitation, addition, or
other improvement of a structure, the cost of which equals or exceeds 50 percent of the
market value of the structure before the "start of construction" of the improvement. This
term includes structures that have incurred "substantial damage," regardless of the
actual repair work performed. The term does not, however, include either:
a. Any project for improvement of a structure to correct previously
identified 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 necessaryto assure safe living conditions; or
b. Any alteration of a "historic structure," provided that the alteration will
not preclude the structure's continued designation as "historic structure."
43. Variance: A grant of relief by a community from the terms of a floodplain
management regulation.
44. Violation: The failure of a structure or other development to be fully
compliant with the community's floodplain management regulations. A structure or
other development without the elevation certificate, other certifications, or other
evidence of compliance required in this chapter is presumed to be in violation until su ch
time as that documentation is a grant of relief by a community from the terms of a
floodplain management regulation.
45. Water surface elevation: The height, in relation to the vertical datum
utilized in the applicable flood insurance study of floods of various magnitudes and
frequencies in the floodplains of coastal or riverine areas.
46. Water Dependent: A structure for commerce or industry that cannot exist
in any other location and is dependent on the water by reason of the intrinsic nature of
its operations.
Section 6. TMC Section 16.52.040 is hereby reenacted to read as follows:
16.52.040 Applicability
This chapter applies to all special flood hazard areas within the City of Tukwila
jurisdiction.
Section 7. TMC Section 16.52.050 is hereby reenacted to read as follows:
16.52.050 Basis for Establishing the Areas of Special Flood Hazard
A. The special flood hazard areas identified by the Federal Insurance
Administrator in a scientific and engineering reportentitled "The Flood Insurance Study
(FIS) for King County, Washington and Incorporated Areas" dated August 19, 2020,
and any revisions thereto, with accompanying Flood Insurance Rate Maps (FIRMs)
dated August 19, 2020, and any revisions thereto, are hereby adopted by reference
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and declared to be a part of this chapter. The FIS and the FIRMs are on file at 6300
South center Boulevard, Suite 100.
B. The best available information forflood hazard area identification as outlined in
TMC Section 16.52.080.C.2 shall be the basis for regulation until anew FIRM is issued
which incorporates this data.
Section 8. TMC Section 16.52.060 is hereby reenacted to read as follows:
16.52.060 Interpretation
In the interpretation and application of TMC Chapter 16.42, all provisions shall be:
1. Considered as minimum requirements;
2. Liberally construed in favor of the governing body; and
3. Deemed neither to limit nor repeal any other powers granted under State
statutes.
Section 9. TMC Section 16.52.070 is hereby reenacted to read as follows:
16.52.070 Warning and Disclaimer of Liability
The degree of flood protection required by TMC Chapter 16.52 is considered
reasonable for regulatory purposes and is based on scientific and engineering
considerations. Largerfloodscan andwilloccuron rare occasions. Flood heights may
be increased by man-made or natural causes. This chapter does not imply that land
outside the areas of special flood hazards or uses permitted within such areas will be
free from flooding orflood damages. This chapter shall not create liability on the part of
the City of Tukwila, any officer or employee thereof, or the Federal Insurance
Administration for any flood damages that result from reliance on this chapter or any
administrative decision lawfully made hereunder.
Section 10. TMC Section 16.52.080 is hereby reenacted to read as follows:
16.52.080 Administration
A. The Public Works Director is hereby appointed to administer, implement, and
enforce this ordinance by granting or denying development permits in accordance with
its provisions. The Floodplain Administrator may delegate authority to implement these
provisions.
B. The Director may:
1. Restrict or prohibit development that is 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;
2. Require that development vulnerable to floods be protected against flood
damage at the time of initial construction;
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3. Control the alteration of natural floodplains, stream channels, and natural
protective barriers, which help accommodate or channel floodwaters;
4. Control filling, grading, dredging and other development which may
increase flood damage; and
5. Prevent or regulate the construction of flood barriers that would unnaturally
divert floodwaters or that might increase flood hazards in other areas.
C. The Director's duties shall include, butshall not be limited to:
1. Permit Review.
a. Review all development permits to determine that the permit
requirements of this chapter have been satisfied.
b. 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.
c. The site is reasonably safe from flooding.
d. Review all development permits to determine if the proposed
development is located in the floodway, and ensure that the encroachment provisions of
TMC Section 16.52.110, "Floodways," are met.
Area.
e. Notify FEMA when annexations occur in the Special Flood Hazard
2. Special Flood Hazard Area.
a. When base flood elevation data has not been provided in A zones, th e
Director shall obtain, review, and reasonably utilize any base flood elevation and
floodway data available from a Federal, State or other source, in order to administer
TMC Chapter 16.52.
b. Where elevation data is not available either through the FIS, FIRM, or
from another authoritative source (TMC Section 16.52.080), applications for floodplain
development 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 the highest adjacent grade in these zones may
result in higher insurance rates.
c. Where needed, the Director shall interpret 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 Director
shall provide the person contesting the boundary location a reasonable opportunity to
appeal the interpretation. Such appeals 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).
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3. Changes to Special Flood Hazard Area.
a. If a project will alter the Base Flood Elevation (BFE) or boundaries of
the Special Flood Hazard Area (SFHA), then the project proponent shall provide the
community with engineering documentation and analysis regarding the proposed
change. If the change to the BFE or boundaries of the SFHA would normally requ ire a
Letter of Map Change, then the project proponent shall initiate, and receive approval of,
a Conditional Letter of Map Revision (CLOMR) prior to approval of the development
permit. The project shall be constructed in a manner consistent with the approved
CLOMR.
b. If a CLOMR application is made, the project proponent shall also
supply the full CLOMR documentation package to the Floodplain Administrator to be
attached to the floodplain development permit, including all required property owner
notifications.
4. Watercourse Alteration.
a. Notify adjacent communities and the Department of Ecology (DOE)
prior to any alteration or relocation of a watercourse, and submit evidence of such
notification to the Federal Insurance Administration through appropriate notification
means. (44 CFR 60.3(b)(6))
b. Require that maintenance be provided within the altered or relocated
portion of said watercourse so thatthe flood carrying capacity is notdiminished.
5. Information to be Obtained and Maintained.
a. Where base flood elevation data is provided through the FIS, FIRM, or
required as in TMC Section 16.52.080.C.2, obtain and maintain a record of the actual
(as -built) 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.
b. For all new or substantially improved flood -proofed nonresidential
structures where base flood elevation data is provided through the FIS, FIRM, or as
required in TMC Section 16.52.080.C.2:
(1) Obtain and maintain a record of the elevation (in relation to mean
sea level)to which the structure wasflood-proofed.
16.52.090, D.3.
issuance.
(2) Maintain the floodproofing certifications required in TMC Section
c. Certification required by TMC Section 16.52.110.A.1.
d. Records of all variance actions, including justification for their
e. Improvement and damage calculations.
f. Maintain for public inspection all records pertaining to the provisions of
this ordinance.
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Section 11. TMC Section 16.52.090 is hereby reenacted to read as follows:
16.52.090 Permits
A. A Flood Zone Control Permit (FZCP) shall be obtained before construction or
development begins within any area of special flood hazard established in TMC Section
16.52.050. The permit shall be for all structures including manufactured homes, as set
forth in the "Definitions," and for all development including clearing, filling, grading, and
other activities, also as set forth in the "Definitions."
B. Application for an FZCP shall be submitted with the project application for a
clearing and grading permit, shoreline permit, plat or subdivision permit, or a building
permit, whichever comes first.
C. An FZCP is a Type 1 permit processed pursuantto TMC Section 18.108.010.
D. Application foran FZCP shall be made on forms furnished bythe City and shall
meet the City's standards for plan submittals. The applicant must provide the following
information:
1. Elevation in relation to mean sea level, of the lowest floor (including
basement) of all structures recorded on a current elevation certificate with Section B
completed by the Floodplain Administrator;
2. Elevation in relation to mean sea level to which any structure has been
flood -proofed;
3. Where a structure is to be flood -proofed, certification by a registered
professional engineer or architect that the flood -proofing methods forany nonresidential
structure meet flood -proofing criteria in TMC Section 16.52.100 B.2;
4. Description of the extent to which a watercourse will be altered or relocated
as a resu It of proposed development;
5. Where development is proposed in a floodway, an engineering analysis
determination of no rise of the Base Flood Elevation, and
6. Any other such information that may be reasonably required by the
Floodplain Administrator in order to review the application.
Section 12. TMC Section 16.52.100 is hereby reenacted to read as follows:
16.52.100 Standards
A. General Standards. In all areas of special flood hazards, the following
standards are required:
1. Elevation. Where flood elevation data is not available, either through the
FIRM or from another authoritative source, all new construction and substantial
improvements shall be elevated at least two feet above the highest adjacent grade.
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2. Anchoring.
a. All new construction and substantial improvements, including those
related to manufactured homes, shall be anchored to prevent flotation, collapse, or
lateral movement of the structure resulting from hydrodynamic and hydrostatic loads,
including the effects of buoyancy.
b. All manufactured homes shall 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 orframe ties to ground anchors.
3. Construction Materials and Methods.
a. All new construction and substantial improvements shall be
constructed with materials and utility equipment resistantto flood damage.
b. All new construction and substantial improvements shall be
constructed using methods and practices that minimize flood damage.
c. All new construction and substantial improvements on slopes shall
have drainage paths to guide floodwaters around and away from proposed structures.
d. Electrical, heating, ventilation, plumbing and air-conditioning
equipment and other service facilities shall be designed and/or otherwise elevated or
located so as to prevent water from entering or accumulating within the components
during conditions of flooding.
4. Storage of Materials and Equipment.
a. The storage or processing of materials that could be injurious to
human, animal, or plant life if released due to damage from flooding are prohibited in
special flood hazard areas.
b. Storage of other material or equipment may be allowed if not subject to
damage by floods and if firmly anchored to prevent flotation, or if readily removable from
the area within the time available afterflood warning.
5. Utilities.
a. All new and replacement water supply systems shall be designed to
minimize or eliminate infiltration of floodwaters into the systems;
b. A proposed water well shall be approved by Department of Ecology
and be located on high ground that is not in the floodway;
c. New and replacement sanitary sewage systems shall be designed to
minimize or eliminate infiltration of flood waters into the systems and discharges from
the systems into floodwaters; and
d. Onsite waste disposal systems shall be located to avoid impairment to
them or contamination from them during flooding.
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6. Subdivision Proposals and Development. All subdivisions, as well as new
development shall:
a. Be consistentwith the need to minimize flood damage;
b. Have public utilities and facilities — such as sewer, gas, electrical and
water systems — located and constructed to minimize or eliminateflood damage;
c. Have adequate drainage provided, to reduce exposure to flood
damage; and,
Cl. Where subdivision proposals and other proposed developments
contain greater than 50 lots or 5 acres (whichever is the lesser), base flood elevation
data shall be included as part of the application.
B. Specific Standards. In all areas of special flood hazards where Base Flood
Elevation data has been provided as set forth in TMC Section 16.52.050 or TMC
Section 16.52.080.C.2, the following provisions are required:
1. Residential Construction.
a. New construction and substantial improvement of any residential
structure shall have the lowest floor, including basement, elevated one foot or more
above the Base Flood Elevation. Mechanical equipment and utilities shall be
waterproofed or elevated one or more feet above the Base Flood Elevation.
b. Fully enclosed areas below the lowest floor that are subject to flooding
are prohibited, or shall be designed to automatically equalize hydrostatic 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,
and must meet or exceed the following minimum criteria:
(1) A minimum of two openings having a total netarea of not less than
one square inch for every square foot of enclosed area subject to flooding shall be
provided.
(2) The bottom of all openings shall be no higher than one foot above
grade.
(3) Openings may be equipped with screens, louvers, or other
coverings or devices provided that they permit the automatic entry and exit of
floodwaters.
2. Nonresidential Construction:
a. New construction and substantial improvement of any commercial,
industrial or other nonresidential structure shall either have the lowest floor, including
basement, elevated one foot or more above the base flood elevation, or elevated as
required by ASCE 24, whichever is greater, or together with attendant utility and
sanitary facilities, shall:
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(1) Be dry flood -proofed so that below one foot or more above the
base flood level the structure is watertight with walls substantially impermeable to the
passage of water or dry flood -proofed to the elevation required by ASCE 24, whichever
is greater;
(2) Have structural components capable of resisting hydrostatic and
hydrodynamic loads and effects of buoyancy; and
(3) Be certified by a registered professional engineer or 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 and/or
review of the structural design, specifications and plans. Such certifications shall be
provided to the official as set forth in TMC Section 16.52.080.0.5.
b. Nonresidential structures that are elevated, not flood -proofed, must
meet the same standards for space below the lowest floor as described in TMC Section
16.52.100, B.1.b., for residential construction.
c. The City shall notify applicants who propose to flood -proof
nonresidential buildings that flood insurance premiums will be based on rates that are
one foot below the flood -proofed level (e.g. a building flood -proofed to the base flood
level will berated as one foot below). Flood -proofing the building an additional foot will
reduce insurance premiums significantly.
3. Manufactured Homes:
a. All manufactured homes to be placed or substantially improved on
sites, outside of a manufactured home park or subdivision, in a new manufactured
home park or subdivision, in an expansion to an existing manufactured home park or
subdivision, or in an existing manufactured home park or subdivision on which a
manufactured home has incurred "substantial damage" as the result of a flood, shall be
elevated on a permanent foundation such that the lowest floor of the manufactured
home is elevated one foot or more above the base flood elevation and be securely
anchored to an adequately -designed foundation system to resist flotation, collapse and
lateral movement.
b. Manufactured homesto be placed or substantially improved on sites in
an existing manufactured home park or subdivision that are not subject to the above
manufactured home provisions shall be elevated so that either:
(1) The lowest floor of the manufactured home is elevated one foot or
more above the base flood elevation, or
(2) The manufactured home chassis is supported by reinforced piers
or other foundation elements of at least equivalent strength that are no less than 36
inches in height above grade and be securely anchored to an adequately designed
foundation system to resist flotation, collapse and lateral movement.
4. Recreational Vehicles. Recreational vehicles placed on sites are required
to either:
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a. Be on the site for fewer than 180 consecutive days;
b. Be fully licensed and ready for highway use, on its wheels orjacking
system, be attached to the site only by quick disconnect type utilities and security
devices, and have no permanently attached additions; or
c. Meet the requirements for manufactured homes, including the
elevation and anchoring requirements for manufactured homes.
5. Enclosed Areas Below the Lowest Floor. • If buildings or manufactured
homes are constructed or substantially improved with fully -enclosed areas below the
lowest floor, the areas shall be used solely for parking of vehicles, building access, or
storage.
C. Green River. In addition to the general and specific standards in the section,
the following standards applyto all areas adjacent to the Green River:
1. Construction/Reconstruction of Dikes/Levees: As part of the flood -proofing
for developments adjacent to the Green River through Tukwila, construction or
reconstruction of the dike/levee system, in accordance with dike/levee plans and
engineering studies, and in accordance with the Green River Management Agreement
(AG No. 85-043), will be required as part of the plan submittal.
2. If dike/levee improvements are not required, and the natural riverbank is
allowed as bank protection, then a riverbank stability analysis shall be provided to the
Public Works Departmentfor review as part of the plan submittal.
3. Dedication of levee/dike/riverbank access construction and maintenance
easements on all properties adjacent to the Green River shall, as part of their
development, dedicate construction and maintenance easements for access and
maintenance of existing orfuture dikes/levees/riverbanks along the Green Riveras part
of their plan submittal. These easements shall be provided in such a manner so that
immediate access is allowed from other public rights-of-way for maintenance and
construction of dikes/levees.
Section 13. TMC Section 16.52.110 is hereby reenacted to read as follows:
16.52.110 Floodways
A. Located within areas of special flood hazard established in TMC Section
16.52.050 are areas designated as floodways. Since the floodway is an extremely
hazardous area due to the velocity of floodwaters that can carry debris, and increase
erosion potential, the following provisions apply:
1. No Rise Standard. Prohibit encroachments, including fill, new construction,
substantial improvements, and other development, unless certification by a registered
professional engineer is provided demonstrating, through hydrologic and hydraulic
analyses performed in accordance with standard engineering practice, that the
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proposed encroachment would not result in any increase in flood levels during the
occurrence of the base flood discharge.
2. Residential Construction in Floodways. Construction or reconstruction of
residential structures is prohibited within designated floodways, except for: (i) repairs,
reconstruction, or improvements to a structure that do not increase the ground floor
area; and (ii) repairs, reconstruction, or improvements to a structure, 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
that have been identified by the local code enforcement official and that are the
minimum necessary to assure safe living conditions, or to structures identified as
historic places, may be excluded in the 50 percent.
3. Substantially Damaged Residences in Floodway.
a. For all substantially damaged residential structures located in a
designated floodway, the Floodplain Administrator may make a written request that the
Department of Ecology assess the risk of harm to life and property posed by the specific
conditions of the floodway. Based on analysis of depth, velocity, flood -related erosion,
channel migration, debris load potential, and flood warning capability, the Department of
Ecology may exercise best professional judgment in recommending to the local
permitting authority repair, replacement, or relocation of a substantially damaged
structure consistent with WAC 173-158-076. The property owner shall be responsible
for submitting to the local government and the Department of Ecology any information
necessary to complete the assessment. Without a favorable recommendation from the
Department for the repair or replacement of a substantially damaged residential
structure located in the regulatory floodway, no repair or replacement is allowed per
WAC 173-158-070(1).
b. Before the repair, replacement, or reconstruction is started, all
requirements of the NFIP, the state requirements adopted pursuant to 86.16 RCW, and
all applicable local regulations must be satisfied. In addition, the following conditions
must be met:
(1) There is no potential safe building location for the replacement
residential structure on the same property outside the regulatoryfloodway.
(2) A replacement residential structure is a residential structure built
as a substitutefora legallyexisting residential structure of equivalent use and size.
(3) Repairs, reconstruction, or replacement of a residential structure
shall notincrease the total square footage of floodway encroachment.
(4) The elevation of the lowest floor of the substantially damaged or
replacement residential structure is a minimum of one foot higherthan the Base Flood
Elevation.
(5) New and replacement water supply systems are designed to
eliminate or minimize infiltration of floodwater into the system.
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(6) New and replacement sanitary sewerage systems are designed
and located to eliminate or minimize infiltration of floodwater into the system and
discharge from the system into the floodwaters.
(7) All other utilities and connections to public utilities are designed,
constructed, and located to eliminate or minimize flood damage.
B. All Other Building Standards Apply in the Floodway. If TMC Section
16.52.110.A.1 is satisfied or construction is allowed pursuant to TMC Section
16.52.110.A.2, all new construction and substantial improvements shall complywith all
applicable flood hazard reduction provisions of TMC Section 16.52.100.
Section 14. TMC Section 16.52.120 is hereby reenacted to read as follows:
16.52.120 Critical Facility
Construction of new critical facilities shall be, to the extent possible, located outside
the limits of the Special Flood Hazard Area (SFHA). The Director may permit
construction of a new critical facility within the SFHA if no feasible alternative is
available. Critical facilities constructed within the SFHA shall have the lowest floor
elevated three feet above base flood elevation or elevated to the 500 -year flood
elevation, whichever is higher. Flood -proofing and sealing measures must betaken to
ensure that toxic substances will not be displaced by or released into floodwaters.
Access to and from the critical facility should also be protected to the height utilized
above. Access routes elevated to or above the level of the base flood elevation shall be
provided to all critical facilities to the extent possible.
Section 15. TMC Section 16.52.125 is hereby established to read as follows:
16.52.125 Compliance
All development within special flood hazard areas is subject to the terms of this
ordinance and otherapplicable regulations.
Section 16. TMC Section 16.52.130 is hereby reenacted to read as follows:
16.52.130 Penalties
No structure or land shall hereafter be constructed, located, extended, converted or
altered without full compliance with the terms of this chapter and other applicable
regulations. Violations 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 constitute a misdemeanor. Any person who violates
this chapter or fails to comply with any of its requirements shall upon conviction thereof
be fined not more than $1,000, or imprisoned for not more than 90 days, or both, for
each violation, and in addition shall pay all costs and expenses involved in the case.
Nothing herein contained shall preventthe City of Tukwila from taking such otherlawfu I
action as is necessaryto prevent or remedy anyviolation.
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Section 17. TMC Section 16.52.140 is hereby reenacted to read as follows:
16.52.140 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.
Section 18. Corrections by City Clerk or Code Reviser. Upon approval of the
City Attorney, the City Clerk and the code reviser are authorized to make necessary
corrections to this ordinance, including the correction of clerical errors; references to
other local, state or federal laws, codes, rules, or regulations; or ordinance numbering
and section/subsection numbering.
Section 19. Severability. This ordinance and the various parts thereof are hereby
declared to be severable. Should any Section of this ordinance be declared by the
courts to be unconstitutional or invalid, such decision shall not affectthe validity of the
ordinance as a whole, or any portion thereof other than the Section so declared to be
unconstitutional or invalid.
Section 20. Effective Date. This ordinance or a summary thereof shall be
published in the official newspaper of the City, and shall take effect and be in full force
five days after passage and publication as provided by law.
PASSED BY THE CITY COUNCIL OF THE CITY OF TUKWILA, WASHINGTON, at
a Regular Meeting thereof this day of , 2020•
ATTEST/AUTHENTICATED:
Christy O'Flaherty, MMC, City Clerk
APPROVED AS TO FORM BY:
Office of the City Attorney
Allan Ekberg, Mayor
Filed with the City Clerk:
Passed by the City Council:
Published:
Effective Date:
Ordinance Number:
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