HomeMy WebLinkAboutSpecial 2025-01-12 Item 2B - Resolution - Hazard Mitigation Plan AnnexCity of Tukwila
Thomas McLeod, Mayor
Marty Wine, City Administrator
AGENDA BILL
ITEM NO.
4.B. &
Spec 2.B.
Agenda Item
Tukwila Hazard Mitigation Plan Annex Adoption
Sponsor Mindi Mattson
Mayor's Office
Legislative History January 12, 2026 Committee of the Whole
January 12, 2026 Special Meeting
Recommended Motion ❑ Discussion Only ❑x Action Requested
MOVE TO Adopt Hazard Mitigation Plan Annex
EXECUTIVE SUMMARY
Tukwila Participates in King County's Hazard Mitigation Program by annexing to the King County
Hazard Mitigation Plan. Tukwila's Hazard Mitigation Plan Annex is ready for review and adoption by
Council.
DISCUSSION
The Hazard Mitigation Plan for King County allows each City to provide a city -specific Annex to be
included in the County's plan. The plan and annexes outline the strategy for mitigating hazards in the
County. This includes identification of hazards, projects, funding, priorities and strategies for the County
and each individual city. The Tukwila Hazard Mitigation Plan Annex was developed with input from City
staff subject matter experts. Once adopted by Tukwila Council, the Annex will become part of the King
County Hazard Mitigation Plan. This maintains the City's ability to maintain eligibility to apply for hazard
mitigation grants to further the priorities identified in the Annex.
FINANCIAL IMPACT
N/A
ATTACHMENTS
Proposed Resolution
Proposed Tukwila Hazard Mitigation Plan Annex
8
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF
TUKWILA, WASHINGTON, ADOPTING THE TUKWILA HAZARD
MITIGATION PLAN; REPEALING RESOLUTION NO. 1995.
WHEREAS, the City of Tukwila and surrounding areas are subject to various hazards, including
flooding, earthquakes, landslides, severe windstorms and other natural and technological/man-made
hazards; and
WHEREAS, the City of Tukwila is committed to strengthening the City's resilience to the effects
of natural and technological/man-made hazards; and
WHEREAS, the Federal Disaster Mitigation Act of 2000, specifically Section 322, addresses local
mitigation planning and requires local governments to develop Local Hazard Mitigation Plans as a
condition of receiving Hazard Mitigation Grant Program funding, Flood Management Assistance, and
Pre -Disaster Mitigation funding from the Federal Emergency Management Agency (FEMA); and
WHEREAS, FEMA is completing a pre -adoption review of the City's Hazard Mitigation Plan
Annex and will approve the Plan upon receiving documentation of its adoption by the City;
NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF TUKWILA, WASHINGTON,
HEREBY RESOLVES AS FOLLOWS:
The City Council approves participation in the hazard mitigation planning process, development
of a City-wide Hazard Mitigation Plan Annex and adoption of the proposed Hazard Mitigation Plan
Annex subject to FEMA approval, hereby incorporated by reference as "Attachment A."
PASSED BY THE CITY COUNCIL OF THE CITY OF TUKWILA, WASHINGTON, at a Special
Meeting thereof this day of , 2026.
ATTEST/AUTHENTICATED:
Andy Youn-Barnett, City Clerk Armen Papyan , Council President
APPROVED AS TO FORM BY:
Office of the City Attorney
Filed with the City Clerk:
Passed by the City Council:
Resolution Number:
Attachment A: Tukwila Hazard Mitigation Plan ("City of Tukwila Plan Annex")
2026 Legislation: Hazard Mitigation Plan
Version: 1/5/2026
Staff: M. Mattson
Page 1 of 1
9
City of Tukwila Plan Annex
Introduction
Tukwila Snapshot (Using data from the U.S. Census Bureau,
Washington State Office of Financial Management, Puget Sound
Regional Council, and other sources):
• Tukwila is located in the heart of the Puget Sound region,
approximately 12 miles south of downtown Seattle, 17 miles north of
Tacoma, and just east of Seattle -Tacoma International airport.
• Tukwila is 9.2 square miles in size (2020), with a population of 2,373
persons per square mile.
• Tukwila had an estimated population of 22,780 in 2023 and had an
estimated employment of around 45,825 in 2022. Between 2018 and
2022, more than 82 percent of those 25 years and older reported
being a high school graduate, and 26 percent had a bachelor's degree
or higher.
• Tukwila is an increasingly diverse city, with more than 69 percent of
its population identifying as nonwhite in 2023, and 40 percent born
outside of the United States or Puerto Rico. Approximately 47
percent of the residents speak a language other than English at home.
• As of 2023, Tukwila had estimated 8,098 households with an
average of 2.64 persons per household.
• Tukwila's 2023 median household income was $76,331, and the
Census Bureau estimates that 13.3 percent of the city's residents live
in poverty.
• In 2023, 18 percent of the population was under 18 years old, and
11 percent were over 65 years old.
• Tukwila has more than 2,000 businesses, which comprise over
40,000 jobs. Businesses cover multiple sectors with concentrations in
retail, manufacturing, services, and distribution and specialties in
entertainment and aerospace.
• Between 2018 and 2022, 72 percent of the population age 16 and up
participated in the civilian labor force.
Governing Format
• Tukwila, incorporated on June 23, 1908, is a non -charter, optional
code city operating under a Mayor -Council form of government,
which includes a full-time Mayor, seven -member City Council elected
at large, and a City Administrator. All elected official terms are for a
period of four years. Mayor McLeod is the chief executive officer, and
the Council is the legislative branch and governing body. City
management includes a City Administrator, Deputy City
Administrator, nine department heads, 269 full-time employees and
91 part time employees. The current operating budget of the city for
2025 is $163,747,027
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City of Tukwila Hazard Mitigation Plan Page 1 ,� 0
Tukwila Snapshot (Using data from the U.S. Census Bureau, Washington State Office of Financial Management,
Puget Sound Regional Council, and other sources):
• Tukwila is located in the heart of the Puget Sound region, approximately 12 miles south of downtown Seattle, 17
miles north of Tacoma, and just east of Seattle -Tacoma International airport.
• Tukwila is 9.2 square miles in size (2020), with a population of 2,373 persons per square mile.
• Tukwila had an estimated population of 22,780 in 2023 and had an estimated employment of around 45,825 in
2022. Between 2018 and 2022, more than 82 percent of those 25 years and older reported being a high school
graduate, and 26 percent had a bachelor's degree or higher.
• Tukwila is an increasingly diverse city, with more than 69 percent of its population identifying as nonwhite in
2023, and 40 percent born outside of the United States or Puerto Rico. Approximately 47 percent of the residents
speak a language other than English at home.
• As of 2023, Tukwila had estimated 8,098 households with an average of 2.64 persons per household.
• Tukwila's 2023 median household income was $76,331, and the Census Bureau estimates that 13.3 percent of the
city's residents live in poverty.
• In 2023, 18 percent of the population was under 18 years old, and 11 percent were over 65 years old.
• Tukwila has more than 2,000 businesses, which comprise over 40,000 jobs. Businesses cover multiple sectors
with concentrations in retail, manufacturing, services, and distribution and specialties in entertainment and
aerospace.
• Between 2018 and 2022, 72 percent of the population age 16 and up participated in the civilian labor force.
Governing Format
• Tukwila, incorporated on June 23, 1908, is a non -charter, optional code city operating under a Mayor -Council
form of government, which includes a full-time Mayor, seven -member City Council elected at large, and a City
Administrator. All elected official terms are for a period of four years. Mayor McLeod is the chief executive
officer, and the Council is the legislative branch and governing body. City management includes a City
Administrator, Deputy City Administrator, nine department heads, 269 full-time employees and 91 part time
employees. The current operating budget of the city for 2025 is $163,747,027
Development Trends
Since 1990, the City of Tukwila has experienced modest but steady population growth (not including
annexations). While Tukwila's residential population remains relatively small, the city functions as a major regional
employment and activity center, resulting in development patterns that differ from those of primarily residential
jurisdictions.
Tukwila's nighttime population is approximately 22,780 residents as of 2023 and is expected to grow gradually as
additional housing is delivered. In contrast, the city's daytime population remains significantly larger - estimated
between 150,000 and 170,000 people on a typical weekday - reflecting the concentration of employment, regional
retail, industrial uses, and transportation facilities. This daytime population, roughly seven to eight times greater
than the residential population, has important implications for infrastructure demand, emergency response, and
hazard mitigation planning.
11 City of Tukwila Hazard Mitigation Plan Page 2
Development activity in Tukwila is generally grouped into five areas: the Tukwila Urban Center/Southcenter area,
the Manufacturing/Industrial Center, the Tukwila International Boulevard corridor, Tukwila South, and the city's
remaining residential and commercial neighborhoods.
Tukwila Urban Center (TUC)/Southcenter Area — A high -density, regionally oriented mixed -use urban center
that includes major retail, employment, entertainment, and an expanding residential base. Development in this area
is primarily vertical, with mid -rise and high-rise buildings, and is supported by substantial transportation
infrastructure. The concentration of activity and critical facilities as well as the proximity to the Green and
Duwamish River makes this area a focal point for emergency preparedness and infrastructure resilience planning.
Manufacturing/Industrial Center — A large employment district along the Duwamish River characterized by
manufacturing, warehousing, logistics, and industrial uses. This area supports a significant share of the city's
employment base and includes critical freight and utility infrastructure. Portions of the area are located near flood -
prone or liquefaction -susceptible lands, requiring careful consideration of hazard exposure and continuity of
operations.
Tukwila International Boulevard (TIB) Corridor — A transitioning corridor anchored by Link light rail service
and characterized by mid -rise residential, mixed -use, and commercial development. Ongoing redevelopment is
increasing residential density and activity levels, particularly near station areas, while older commercial uses remain
interspersed along the corridor. Proximity to major transportation infrastructure and variable site conditions
present both redevelopment opportunities and hazard planning considerations.
Tukwila South — A large area at the southern end of the city along the Green River identified for long-term
redevelopment and intensification. The area includes extensive environmental constraints and infrastructure needs,
and development is expected to occur incrementally over time. Past and future site preparation, including grading
and floodplain management, play an important role in reducing flood risk and shaping long-term development
potential.
More broadly, the city continues to see strong market interest in mid -rise residential development, driven by
limited land availability and proximity to transit and services. Recently completed or soon -to -be completed.
projects such as Prose Tukwila in the Tukwila Urban Center and Village at 47th in the Ryan Hill area illustrate this
trend. These developments reflect a continued shift toward compact, multi -story housing forms that align with
Comprehensive Plan goals to concentrate growth in designated centers and corridors.
Recent state -required regulatory changes implementing middle housing provisions under HB 1110 have also begun
to influence development patterns. In Tukwila, this shift is reflected in the transition from the former Low Density
Residential (LDR) zoning designation to the new Community Residential (CR) zone, which combines elements of
the former LDR and Medium Density Residential (MDR) zones. Early development interest indicates growing
consideration of duplexes, triplexes, fourplexes, and other middle housing types on lots that were historically
developed with single-family homes. Over time, these changes are expected to incrementally increase housing
capacity while maintaining neighborhood -scale development patterns.
Overall development capacity remains constrained by limited land availability and existing development patterns.
As a result, most residential growth is likely to occur through middle housing infill on CR lots and the occasional
mixed-use/multi-family project in the TIB and TUC subareas. At the same time, continued development pressure
increasingly affects parcels encumbered by critical areas, including steep slopes, wetlands, and streams. While the
city regulates development to avoid direct impacts to these areas where feasible, their presence introduces
additional environmental risk and development challenges. These constraints require careful site design, mitigation,
and long-term monitoring and remain an important consideration from an environmental and hazard mitigation
perspective as Tukwila continues to grow.
City of Tukwila Hazard Mitigation Plan
Page 3 12
urisdiction Point of Contact:
Name: Pete Mayer
Title: EM Director/Deputy City
Administrator
Entity: City of Tukwila
Phone: (206)767-2305
Email: pete.mayer@tukwilawa.gov
Plan Prepared By:
Name: Mindi Mattson
Title: Emergency Manager
Entity: City of Tukwila
Phone: (206)673-7480
13 City of Tukwila Hazard Mitigation Plan
Page 4
City of Tukwila Risk Summary
Hazard Risk and Vulnerability Summary
HAZARD
Avalanche
Dam
Failure
Earthquake
HAZARD
SUMMARY
VULNERABILITY IMPACT
SUMMARY , SUMMARY
Tukwila is not NA NA
within an
avalanche
zone.
Flood
protection for
much of
Tukwila that
is in the valley
is provided by
the Howard
Hanson dam.
The dam is a
USACE
project built
in 1962 and
located
approxitnately
35 miles
upriver from
Tukwila. The
King County
Flood Control
District assists
with
downstream
management
of flood
protection.
Like most of
the Pacific
Northwest,
earthquakes
are likely the
This likelihood
of a complete
dam failure is
very low due to
diligent,
competent
management of
the project by
the US Army
Corps of
Engineers.
However, an
event such as a
major
earthquake or
terrorist attack
could result in
dam failure.
Tukwila has a
significant
amount of
structures and
infrastructure
The total release
of water stored
at the dam
would result in
extensive
flooding to all
downstream
communities
including
Tukwila. Being
the furthest
community
downstream,
Tukwila would
have the most
time for
response efforts
including
evacuations and
hardening of
buildings in the
flood plane.
However, being
further
downstream may
result in larger
levels of debris
and hazardous
PROBABILITY OF
FUTURE
OCCURRENCE
(INCLUDE
EFFECTS OF
CLIMATE
CHANGE)
NA
material deposits
from upstream
communities.
An An earthquake
in or near
Tukwila could
result in
outcomes
To date the
USACE have
been able to
accommodate
for changing
weather patterns
resulting in
variations to the
water storage
needs at the
project.
Predictability of a
total dam failure
is very low
because the most
likely causes are
either less
predictable
hazards
(earthquakes)
and man-made
hazards
(terrorism).
While
earthquakes are
not predictable,
the historic
intervals and
City of Tukwila Hazard Mitigation Plan
Page 5 14
Flood
Landslide
highest
impact
disaster for
Tukwila. We
are
susceptible to
crustal,
intraplate, and
subduction
zone quakes.
The city is
bisected by
the Green and
Duivamish
River which,
runs the
entire city
from north to
south.
Landslides
typically occur
when the
earth is
unstable and
the slope is
excessive.
There is often
a triggering
event such as
excessive rain
or earthquake.
that were built
prior to curren
standards,
including
concrete tilt -up
buildings,
unreinforced
masonry, and
bridges. Bridges
are of high
concern due to
the potential
isolation of
some or many
of our
communities, as
well as the large
volume of
traffic that
passes through
Tukwila.
................................................
There are
multiple
residential and
commercial
properties
including a
professional
rugby/soccer
complex and a
golf course that
may be affected
by a100year
event.
There is one
known area
prone to
landslide in the
city adjacent to
Interurban Ave
South at the
15200 block.
Canyon Estates
Condos sit
above the
potential slide
area. The area is
marked and
slope
ranging from
inconvenient to
catastrophic
depending on
the severity. A
quake could
impact much of
the critical
infrastructure
making it
difficult to
provide essential
services. It
would greatly
overwhelm
regional services
and significantly
impact both
residents and
visitors.
With climate
change,
° population and
development
growth, impacts
from flooding
will remain
impactful.
A landslide in
the known area
could cause life
safety issues,
traffic issues,
and property
damage to public
and private
property.
years since the
last major quake
in this region
could be
interpreted as the
region being
"overdue" for a
major
occurrence.
While the
impacts of
climate change
are anticipated to
be significant for
our region, there
is not currently
data correlating
earthquake
outcomes and
climate change.
There is a plan to
reinforce the
levees
throughout the
City to lessen
flood impacts.
Climate change
may increase
rainfall amounts
to slide -prone
areas. The city
recently hired a
Geotech
consultant to
provide detailed
landslide
information and
mapping. The
report will be
available Q1
2026 and
15
City of Tukwila Hazard Mitigation Plan Page 6
Extreme
Weather
Tsunami
Volcano
Wildfire
stabilization
and debris
mitigation
measures have
been
implemented.
findings will be
incorporated in
this annex in the
future.
Tukwa ' Due to The :2021 Heat Occurrencesof
experiences demographics, Dome was an extreme weather
extreme geography and example of an will continue to
weather in the topography, extreme weather be irripactful to
orm of wind, Tukwila is event. There the city. Climate
in, snow, prone to have also been change may
ice, and heat. extreme significant rain, bring more
weather events snow, and ice frequent,
and their ' events causing extreme events.
outcomes.
A tsunami is
most likely to
occur from an
earthquake
creating wave
activity that
reaches
land/shore.
e Cascade
mountain
range
contains
multiple
active
volcanos that
could impact
e city.
Any tsunamic
activity that
reached the city
would come
through Puget
Sound and up
through the
Duwamish river
resulting in tidal
surge.
While lahars are
not likely to
reach the city,
debris and ash
flows could be
significant
depending on
wind and other
uweather.
conditions
While the city j Since the city is
is bordered by largely built out
mostly urban in terms of
areas, there business and
localized
flooding,
accidents,
damage to
property, loss
power and
disruption of
911'services.
Based on
tsunami
modeling for
Puget Sound, the
likelihood of
impacts in
Tukwila is
considered to be
low.
large ash
r deposit can pose
significant Health
risks for humans
ncl animalst It
would cause
igniftcant:
impacts to
agriculture,
transportation
1 and;
infrastructure
incltading
emergency`
ervices.
Fires in these
areas are
adequately
covered by
ee Earthquake
information
above. While the
modeling gives
us a good
indicator of
impacts,
prediction of an
earthquake is
very imprecise.
Predictions of
Volcanic activity
imprecise,
although often
activity will be
detected prior to
a large eruption.
The city would
ely on existing
geotechnical.
monitoring and
otiftcation of a
ending event.
While wildfire
risk in Tukwila is
considered low,
fire activity due
City of Tukwila Hazard Mitigation Plan
Page 7 16
Civil
Disturbance
Cyber
Attack
are several
green belts,
power
easements,
and
undeveloped
areas that
could be
prone to fire.
While civil
disturbance is
not a
common
occurrence ;in
Tukwila, the
city regularly
draws visitors
in large
numbers to
our shopping,
commercial,
retail, dining,
and recreation
offerings,
Cyber Attacks
on
government
occur every
day including
DDOS and
ransom
demands.
residential.
structures, there
aren't large
tracts of
forested land.
The
Department o
Homeland
Security has a
facility in,
Tukwila that
has been the
location of
s repeated;
protests in
2025. These
have been
manageable by
existing law
enforcernen
and mutual
resources. The
Mall and
surrounding
commercial
area are a
gathering spot
for hundreds of
thousands of
visitors,
especially
during the
holiday season..
While no
agency is 100%
immune from
cyber attacks,
Tukwila is
proactive in it's
actions to
prevent being
victimized.
existing
firefighting
resources.
A. -barge civil
disturbance
could result in
significant
disruption to
esidents,
businesses,;
emergency
/ Services,
transportation
and
Corrimunlcations.'
A large
attack could
disable city
government and
disrupt all city
services.
cyber
to climate change
is a rapidly
changing body of
science. Much is
being learned
about urban
interface
wildfires in
communities
with similar
building density.
Current political
conditions have
caused an
increase in
protests/marches
in the area which
have; been mostly,,
peaceful and not
rising to the level
of civil
disturbanc+
Future
occurrences :are
difficult to
edict.
As cyber
criminals become
more evolved,
city defenses
need to keep
pace with new
and novel
attacks. This will.
be a continual
cycle of finding
vulnerabilities
and blocking
them.
17 City of Tukwila Hazard Mitigation Plan
Page 8
Hazardous
Materials
Incident
Public
Health
Emergency
The use and
transport of ,.
hazardous
materials
through
Tukwila via
road and rail
allows for the
potential of
an accidental
discharge or.
spill that
could impact
the
communit
Several gas.
pipelines also
run through
e city.
Tukwila is
vulnerable to
the effects of
a variety of
public health
emergencies
ranging from
food/water
contamination
to rat
infestation to
pandemic.
Tukwila is
home to
transportation
infrastructure
that regularly
carries
hazardous
materials
(primarily rail
and major
highways). The
City also has
businesses
thin the city
that use and
store hazardous
materials.
Tukwila doesn't
have large
health care
providers in the
city. However,
we do
experience large
public
gatherings for
shopping,
recreating, and
sporting and
community
events.
The potential Tukwila's
for terrorism proximity to
is ever- 1 SeaTac I st'1
present. Airport and
ocation in the
greater
Seattle/Tacoma
metropolitan
area make it
vulnerable to a
variety of
terrorism
hreats, both
large and -small
Dependingon
the size,
location, and
material
spilled/released,
a hazrnat
incident in
Tukwila could
significantly
disrupt
government,
commerce,` and
public safety.
The primary
impacts from a
public health
emergency
would be to
government, our
residents,
businesses, and
economy (as
evidenced by
COVID).
Depending on
the type of
attack, the city
anticipates
impacts to <:
government,
public safety,
physical security,
and the
environment.
The City
on the
transporters and
users of
hazardous
materials to
comply with all
safety standards,
as well as the
Puget Sound
Regional Fire
Authority to
maintain
response
capability. The
city is also reliant;
on users,
transporters, and
spillers to work
with us to
mitigate, respond
o, and recover
om a hamat
ncident.
Leadership for
management of a
public health
emergency rests
with Seattle King
County Public
Health. The city
looks to them for
forecasting,
prevention,
mitigation,
response, and
recovery
guidance.
Tukwila PD.
meets all
standards for
erdiction for a
LE organization
of it's size. The
city is reliant on
the Washington
State Fusion
Center, as well as
other state, and
federal partners,
to provide
City of Tukwila Hazard Mitigation Plan
Page 9 18
in scale. Much
of Tukwila lies
inthe
floodplain
below the
Howard
Hanson Dam.
info r ation regarding
terrorism threats
and supportin
responding.
1 9 City of Tukwila Hazard Mitigation Plan
Page 10
Hazard and Asset Overview Map(s)
Hazard Areas:
Tukwila
King County
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City of Tukwila Hazard Mitigation Plan
Page 11 20
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Tukwila
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Floodplain (2020)
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mraie and are intended frn
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21 City of Tukwila Hazard Mitigation Plan
Page 12
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23 City of Tukwila Hazard Mitigation Plan
Page 14
Plan Update Process
Updating the Tukwila Annex to the King County Hazard Mitigation Plan took place over the course of about one
year. Representatives from Tukwila Emergency Management participated in kick-off and workshop events
provided by King County, promoting the county -wide survey conducted, participating in office hours and
individual technical assistance provided by the KCOEM Hazard Mitigation staff.
In partnership with Puget Sound Regional. Fire Authority (Fire/EMS provider for Tukwila), the city conducted an
additional survey to gather feedback more specific to the PSRFA-served cities of Covington, Kent, Maple Valley,
Seatac, and Tukwila. The results of both the county's survey and the PSRFA survey are incorporated into this
Annex.
An internal staff team was identified with the necessary subject matter expertise to oversee the process and update
of the Tukwila Annex. The work began with a comprehensive review of the 2020 Tukwila Annex, as well as the
recently adopted King County Hazard Mitigation Plan (2024). Due to staff turnover and governance changes, few
of the staff who worked on the 2020 Annex were available to provide history or context for the previous planning
efforts. The current Tukwila planning team aimed to understand the intent and provide continuity for the work
done in 2020, while setting forth a fresh vision for hazard mitigation in Tukwila moving forward. The work plan
was established through a series of meetings with Emergency Management, based on mitigation area and subject
matter expertise. Prioritization was done in consultation with department directors and senior city leadership.
Other city-wide planning efforts (including the recently completed Comprehensive Plan, Comprehensive
Emergency Management Plan, Continuity of Operations Plan, and the Capital Improvement Plan Dashboard)
were leveraged to inform this Annex.
As outlined in other sections of this Annex, Tukwila is unique in terms of risk profile, hazards, geography, tax
base, budget, development trends, socio-economic factors, and demographics. These factors influenced the final
contents of this Annex and the prioritization of the projects identified.
City of Tukwila Planning Team
NAME 1 TITLE
ORGANIZATION
CONTRIBUTION
Mindi Emergency City of Tukwila
Mattson Manager Emergency Management
Maxwell Development Dept. of Community
Baker Supervisor Development
Roman GIS Technology and
Linsao Coordinator Innovation Services
Scott Admin. Support Communications/Mayor's
Kirby Coordinator j Office
Will Emergency
Lugo Management
Administrator
Sherry Levee Project I
Edquid Manager/Flood
Plain Manager j
Tony
Cullerton
Planning Coordination
Development Trends
Hazard Maps
Photographs/Logo
Puget Sound Regional
Fire Authority
Public Works Engineering
Deputy Finance Department
Finance
Director
Fire/EMS/EM Subject Matter
Expertise
evee/Flood Risk/Landslide,
formation
Budget Information
City of Tukwila Hazard Mitigation Plan
Page 15 24
Public Works Facilities
2023, 2024, 2025
2025
2025
Nancy'
Eklund
Adam
Cox
Jen
Tetatzin
Mindy
Roberts
Long Range
Planning
Manager
Transportation Public Works Engineering
Project
Manager
D partment + Public Works
Director:
Fiscal
Coordinator
Finance Department
Demographics/Comprehensive
Planning Expertise
Bridges/CIP Expertise
Oversight of PW Staff
Contributions and Project
Prioritization
Personnel Information
Shawn t Internal
Christie Operations
Manager
Plan Update Timeline
PLANNING ACTIVITY
King County Kick-off
Event, Workshop,
Zone 3 Presentation
Meetings with internal
and external subject
matter experts
Submission to King
County for evaluation
of Annex
Adoption By Tukwila
Council
Public Outreach Events
Survey
Conducted by
King County
PSRFA Served
Cities Public
Survey
Quarter 202E
August through
October 2024
City of Tukwila July/August 2024
Targeted Survey
25 City of Tukwila Hazard Mitigation Plan
City -owned Facilities Expertise
St TM'
Participated in these
events as described in the
base plan.
Identified participants
and solicited input for
plan update.
Submit Tukwila Annex to
KCOEM for review and
comment
Present Tukwila Ann
to City Council for
formal adoption
As described in King County
King County HM Residents
Base Plan
Cities of Residents of the
Covington I
Maple Valley, Cities
Seatac and Tukwila
promulgated a
survey through
octal media to
solicit public input,
on local/regional
hazards
Hazard survey
mailed to every
PSRFA Served
All Tukwila
addresses
Mindi Mattson
See "Planning Team"
listed above.
KCOEM Hazard
Mitigation Planning Staff
x I, Tukwila City Council
Page 16
Tukwila address as
part of our
Hazelnut
Newsletter.
The city was also involved in the regional Lower Green River Corridor Flood Hazard Management Plan and the Partner
Planning Committee led by the King County Flood Control District. This plan is a long-term vision for reducing risks
and protecting this vital region. This plan in the future will further outline the capital investment strategy along with
project implementation for the region.
City of Tukwila Hazard Mitigation Plan Page 17 26
27
Tukwila Hazard Mitigation Program
Hazard mitigation is an important part of a comprehensive
Emergency Management planning strategy in the City of Tukwila.
These efforts require the participation of subject matter experts
from multiple departments in the city to properly identify local
hazards and develop strategies to mitigate them. These strategies
were identified prioritized using the process described in the King
County base plan.
The city recently adopted the 2025 Comprehensive Emergency
Management Plan, which is the over -arching strategic plan for all
facets of emergency management, including Prevention,
Protection, Mitigation, Response and Recovery. This Hazard
Mitigation Plan Annex addresses with more specificity the
mitigation components of Tukwila's full -cycle planning efforts.
Plan Monitoring, Implementation, and Future Updates
King County leads the mitigation plan monitoring and update
process and schedules the annual plan check -ins and bi-annual
mitigation strategy updates. Updates on mitigation projects are
solicited by the county for inclusion in the countywide annual
report. As part of participating in the 2025 update to the Regional
Hazard Mitigation Plan, Tukwila agrees to convene their internal
planning team at least annually to review their progress on hazard
mitigation strategies and to update the plan based on new data,
recent disasters, changes in legislative requirement, and potential
funding sources.
As part of leading a countywide planning effort, King County
Emergency Management will send to planning partner any federal notices of funding opportunity for the Hazard
Mitigation Assistance Grant Program or any other funding opportunities that may be introduced in the future.
Proposals from partners will be assessed according the prioritization process identified in this plan and the county
will, where possible, support those partners submitting grant proposals. While the city does take mitigation into
account in establishing funding priorities, pursuing available grant funds will be a key strategy to fund
implementation of this plan.
The Hazard Mitigation Plan is scheduled to be updated every five years, with the next update anticipated in 2030.
The City of Tukwila will submit letters of intent to participate in the 2030 planning process convened by King
County.
Continued Public Participation
Public participation is a foundational strategy shared by King County and its partner cities. The information
developed through this Hazard Mitigation planning effort will he incorporated into outreach and public education
strategies. Any capital improvement projects that are developed from this plan will include appropriate
communication with residents about proposed projects, ensuring our public understands and has input into the
hazards, mitigation efforts, funding, and community impacts. This will include information about local hazard
mitigation efforts, as well as how local projects integrate with County, State and Federal mitigation strategies. The
outreach and mitigation teams will also continue to work with media and other agency partners to publicize
mitigation success stories and help explain how vulnerabilities are being addressed. When possible, the public will
City of Tukwila Hazard Mitigation Plan Page 18
Plan Goals
The goal of the 2025 King
County Regional Hazard
Mitigation Plan: Create a
framework that reduces the
impact and susceptibility of
the identified hazards on
people, property, and the
environment, prioritizing
historically underserved
communities. This framework
takes into account King
County's 15 Determinants of
Equity and Social Justice:
ht s:/iequity--indicators-
kingcounty.hub.arcgis.com/
These population -level
indicators help to better
understand disparities and
opportunities to make a
difference across the
communities we serve.
be given access to mitigation projects to allow community members to see the strategies in this plan brought to
fruition.
Hazard Mitigation Authorities, Responsibilities, and Capabilities
The Hazard Mitigation Plan is one of a suite of Tukwila plans that address the over -arching needs of the city.
While the following list of plans represents "stand alone" documents, they have each been developed to function
in support and coordination of a comprehensive planning strategy.
Plans
PLAN TITLE
RESPONSIBLE POINT OF CONTACT RELATIONSHIP TO HAZARD MITIGATION PLAN
AGENCY
Comprehensive
Plan
Department
of
Community
Development
Nora Gierloff,
Director
The Comprehensive Plan is the "blueprint" that
explains the community's values and priorities to
guide growth and development. The Plan reflects
community involvement, technical analysis, state
and regional requirements, and the judgment of
decision -makers.
Comprehensive
Emergency
Management
Plan
Capital
Improvement
Plan
Emergency;
agemeni
Mayor's
11 flce
Ptufblic Works
Department
Continuity o
Operations Plan
Surface Water,
Water, Sewer,
Transportation
Emergency.
:Management,
Mayor's
Office
Public Works
Pete Mayer,
Director
Jen Tetatzin,
Director
Pete Mayer,
Director
Jen Tetatzin,
Director
Programs, Policies, and Processes
Hazard mitigation is addressed as part of the
Prevention, Protection, Mitigation, Response, and
Recovery scope of the CEMP.
The Capital Improvement Program (CIP) is a
comprehensive multi -year plan of proposed capital.
projects. The plan provides an ongoing framework
for identifying capital needs, scheduling projects
over a period of time, coordinating related projects,
and identifying future fiscal impacts. The city
recently created a dashboard traching all CIP
projects that is available to the public:
https; pis ortal tukwilawavovortaappsciash
boards/ab03a186bf5b4c799fca7d395c1777eb
Availability, suitability of city facilities and cii
departments' ability to function after
disaster/disruption area identified in the CC)C►P
Plans for surface water, water, sewer, and
transportation.
PROGRAM/POLICY
RESPONSIBLE AGENCY
POINT OF CONTACT RELATIONSHIP TO
HAZARD MITIGATION
PLAN
Building Code/Code
Enforcement
Department of
Community
Development
Nick Wagood, Building
Official
Local and international
building codes determine
the design and
City of Tukwila Hazard Mitigation Plan
Page 19 28
29
Emergency j Emergency Management
Management Program Mayor's Office
Critical Areas Department of
Ordinance Community
Public Works
Operations
Development
Public Works
Departments .°
Entities Responsible for Hazard Mitigation
Pete
rer,.Dire r
Nora Gierloff, Director
construction standards
for all projects.
Creates plans and policies
for the administration of
all phases of emergency
management.
Provides regulations for
wetlands, waterways, and
steep slopes.
Engineering,
maintenance and
operation of all ci
infrastructure,
AGENCY/ORGANIZATION POIN'
RESPON SI BIL
(s)
Public Works
Community
Development
Jen Tetatzin
Nora Gierloff
Director of Public Works
Director of Community Development > .
Office of the Mayor Marty Wine 1 City Administrator
Emergency j Pete Mayer r Emergency m Manageent Di
Manm ageent
Puget Sound Regional i Will Lugo 1 Senior Emergency Manager
Fire Authority
National Flood Insurance Program
National Flood Insurance Program Compliance
What department is responsible for
floodplain management in your
community?
Who is your co
admini strator?
rrunity';
le Jpos
7oodplain
ion)
What is the date of adoption of your
flood damage prevention ordinance?
When was the most recent Communit
Assistance Visit or Community
Assistance Contact?
Does your community have any
outstanding NFIP compliance
violations that need to be addressed?
If so, please state what they are?
Do your flood hazard maps adequately
address the flood risk within your
ommunity?ry If so, please state why.
Does your floodplain management
staff need any assistance or training to
support its floodplain management
City of Tukwila Hazard Mitigation Plan
Public Works
Sherry Edquid, Levee Project
Manager, Certified Flood Plain
Manager
2004
ay 2022
No
No known flooding has happened
outside of the identified Special Flood
Hazards
0
Page 20
program? If so, what type of
training/assistance is needed?
Does your community participate in
the Community Rating System (CRS)
If so, what is your CRS Classification
and are you seeing to improve your
rating?If not, is your community
interested in joining CRS?
How many Severe Repetitive Loss SRL: no
(SRL) and Repetitive Loss (RL) RL: no
properties are located in your
jurisdiction?
Has your community ever conducted ` I No
an elevation or buy out of a flood- No
prone property? If so, what fund
source did you use? If not, are you
interested in pursuing buyouts of flood
proneroperties?
Hazard Mitigation Strategies
Below are summaries of the strategies from the 2020 Annex, as well as the proposed strategies for 2025 moving
forward. These are intended to reduce vulnerabilities to hazards identified for Tukwila. The priorities for these
strategies is to reduce the effect of local hazards on all existing and future built environment and infrastructure.
These projects have been vetted internally be appropriate subject matter experts and reviewed by any
2020 Hazard Mitigation Strategy Status
STRATEGY
Bridge Boeing Access/Airport
Maintenance/Improvement Boeing Access/I5
Levee Improvements ; Segale-Gunter
Gaco-Western
Ratolo
Christensen Road
Seismic Upgrades to Fire Survey and
replace/retrofit all fire
stations
Stations
2025 Hazard Mitigation Strategies
STRATEGY
Facilities Tukwila Public
Improvements/Relocation Works/Jen Tetatzin,
Director
(Shawn Christie)
Tukwila Public
Works/Jen Tetatzin,
1 Director
(Sherry Eduid)
Medium
High
As funding comes
available
As, funding comes
available and partner
I agencies are willing .:
Completed. Control of
Fire Stations transferred
to PSRFA per
governance change 2023
PRIORITY
High
High
City of Tukwila Hazard Mitigation Plan
Page 21 30
Bridge Improvements
Hazard M
Tukwila Public
Works/Jen Tetatzin,
Director
(Adam Cox)
tigation Strategy
As funding comes
available and partner
agencies are willing
Lead Points
of Contact:
• Jen
Tetatzin
(Public
Works
Director) •
Shawn
Christie
(PW
Internal
Operations
Manager)
Partner Points of Contact
• King County Office of
Emergency Management
(OEM) — Regional
Coordination • Washington
State Emergency
Management Division
(EMD) — Grants &
Compliance • Public Health
Seattle & King County
— Shelter/ POD
coordination • Seattle City
Light (SCL) — Utility
coordination and
interconnection • American
Red Cross — Shelter
operations support •
Tukwila Parks &
Recreation — Facility
operations (TCC) • Tukwila
Technology and
Innovation Services (TIS) —
Network/Communication
continuity
Hazards Mitigated
/ Goals Addressed:
Upgrade Tukwila
Community
Center
HVAC/Generator
Operations
• Power loss and
service interruption
due to windstorms,
winter storms,
earthquakes, and
flooding •
Continuity of
Operations for life
safety services
(heating/cooling
shelter, POD,
public health,
animal shelter) •
Resilience and
equity: reliable
access to
heat/cooling,
refrigeration,
communications,
and charging for
community
members most
impacted
Funding
Sources and
Estimated
Costs
• Estimated
Total Cost:
$1,750,000
(equipment,
design,
permitting,
installation,
commissioning,
training) •
Potential
Funding
Sources: FEMA
BRIC /HMGP,
WA EMD
passthrough
grants, King
County OEM
support,
Department of
Commerce
Energy
Efficiency
Grants, City
Capital
Improvement
Program (CIP),
Local City
funds
Strategy Vision/Objective
The City of Tukwila Community Center is a major hub for community activities, as
well as the facility designated as a potential emergency shelter, community point of
distribution, public health shelter, animal shelter, and recovery center. A
permanently installed generator will ensure uninterrupted power to critical building
systems during all phases of an emergency.
High
31 City of Tukwila Hazard Mitigation Plan Page 22
Mitigation Strategy
Design, procure, and install a permanent standby generator with automatic transfer
switch (ATS) sized to support critical loads: HVAC for occupied shelter areas,
refrigeration (medications/food), kitchen equipment, lighting for safe egress,
IT/network, radio/charging stations, and life safety systems. Include fuel storage
(or natural gas interconnect), sound attenuation, emissions compliance, and secure
enclosure; update electrical panels; and integrate with facility emergency operations
plans.
2-Year Objectives
• Complete load analysis
and generator sizing for
critical circuits • Finalize
site selection, permitting,
and environmental review
• Prepare grant
applications (i.e. BRIC,
HMGP, King County )
and secure matching
funds Issue RFP and
award design -build or
design -bid -build contract
5-Year Objectives
• Complete installation,
commissioning, and staff
training • Prepare and adopt
Operations and Maintenance
Plan (O&M plan) • Implement
a preventive maintenance
schedule and vendor support •
Conduct annual shelter
activation exercise using
generator power
Implementation Plan/Actions
Long -Term
Objectives:
• Maintain >_ 95%
generator readiness
(tested
monthly/annually) •
Establish multi -year
fuel supply
contracts and parts
inventories •
Explore renewable
integration (solar +
storage microgrid)
to reduce fuel use
and operating cost
• Phase 1 (0-12 months): Load study, design criteria, funding strategy, grant
submissions, permitting • Phase 2 (12-24 months): Procurement, site prep,
electrical upgrades, ATS install • Phase 3 (24-36 months): Generator install,
commissioning, O&M plan, staff training, exercise
• Partners: Public Works (lead), Parks & Rec/Facilities (site operations), TIS
(network loads), SCL (utility), OEM/EMD (grant/admire), Red Cross (shelter),
Public Health (clinical operations)
Performance Measures
• Coverage of critical loads: Percent (%) of prioritized circuits powered during
outage (target >-90%)
• Activation time: ATS transfer and shelter spin -up within 5.5 minutes
• Exercise outcomes: Corrective actions closed within 90 days
• Community impact: Number (#) of residents served during activation;
satisfaction/after-action feedback
City of Tukwila Hazard Mitigation Plan
Page 23 32
Lead Points of
Contact
• Jen Tetatzin
(Public Works
Director) / Shawn
Christie (Internal
Operations
Manager) • Public
Works
Partner Points of
Contact
The Minkler
facility houses
Public Works
emergency
response vehicles
and supplies to
maintain city
infrastructure.
Anyone who
works, lives, or
travels in Tukwila
benefits from
reliable,
coordinated
response capacity,
and mutual aid
partners benefit
from a
nonfloodprone
staging location.
Strategy Vision/Ob ective
Hazards
Mitigated / Goals
Addressed
Relocate
Minkler Shops
to a location
with 500 year
flood protection.
• River flooding
exposure to
critical
fleet/equipment
and supplies •
Continuity of
Operations:
preserve response
capability during
flood events •
Asset protection:
reduce damage,
downtime, and
replacement costs
Funding Sources and
Estimated Costs
Estimated Total
Cost: $30,000,000
(planning, design,
permitting,
construction,
maintenance) •
Potential Funding
Sources: FEMA
BRIC / HMGP, WA
EMD pass -through
grants, King County
OEM support, City
Capital Improvement
Program (CIP), local
match / REET
Relocate Minkler Shops to higher ground outside the Green River floodplain and
construct a resilient Public Works operations center with seismic design, backup
power, secure storage, and all -hazards communications, ensuring uninterrupted
citywide infrastructure response.
Mitigation Strategy
Design and build a facility that is outside the floodplain with hardened utilities;
include permanent generator/ATS, fuel storage, and comms; plan phased move of
equipment and inventory; decommission the Minkler site
2-Year Objectives
• Finalize
SEPA/NEPA/environmental
review and permitting path •
Finalize concept design and
cost estimate • Submit grant
applications and identify local
match; begin property due
diligence
5-Year Objectives
• Demolish old T-
force Buildings,
complete design
development, and
obtain permits •
Begin construction
and phased transition
of fleet/equipment
Long -Term Objectives
• Commission new
facility; achieve full.
operational readiness •
Decommission/repurpose
old site, update flood
response plans and
staging • Maintain
preventive maintenance
and resilience upgrades
over lifecycle
33 City of Tukwila Hazard Mitigation Plan
Page 24
Implementation Plan/Actions
• Phase 1 (0-12 months): Design, environmental scoping, funding strategy
• Phase 2 (12-36 months): Site demolition, design, permits, early works
• Phase 3 (36-60 months): Construction, phased relocation, commissioning
• Partners: Public Works (lead), Finance/Procurement (funding/contracting), King
County, WA Ecology/FEMA/EMD (compliance/grants), Facilities/Real Estate,
Engineering (design)
Performance Measures
• Flood exposure reduction: % decrease in assets located in 100-year floodplain
(target:100% removal)
• Operational continuity: Response KPIs during flood events (downtime hours,
missed routes)
• Project delivery: Major milestones met on time/on budget; grant compliance with
no findings
Lead Points of
Contact:
Adam Cox
Partner Points of Contact
Tukwila Public Works
Maintenance and
Operations and Puget
Sound Fire Authority
Hazards Mitigated
/ Goals Addressed
Prioritize
preventative
maintenance to
bridge elements.
Monitor and
maintain bridge
conditions and
make
improvements as
required.
Funding
Sources and
Estimated
Costs
WSDOT Local
Bridge
Program,
PSRC, and
Move Ahead
Washington
are funding
agencies for
bridge projects
Strategy Vision/Objective
Ensure all 24 bridges in the City have a National Bridge Inventory rating for the
substructure, superstructure, and deck be in satisfactory to good condition. There
are a total of 16 vehicle and 8 pedestrian bridges in the City of Tukwila with two
vehicle bridges being jointly owned with neighboring jurisdictions.
Mitigation Strategy
By studying the required routine bridge inspections, the City has implemented a
Bridge Program that conducts an annual report to observe and document the
current condition of both vehicle and pedestrian bridges. Results from the annual
report will illustrate repair recommendations and future bridge upgrades.
City of Tukwila Hazard Mitigation Plan
Page 25 34
2-Year Objectives
Begin the replacement
of the 42nd Ave S
Bridge.
5-Year Objectives
Monitor bridges that
require seismic upgrades
and possible
repairs/rehabilitation.
Long -Term Objectives
Maintain preventative
maintenance procedures
to extend the design life
of the structures.
Implementation Plan/Actions
Analyzing the Annual City Bridge Inspection Report, City owned structures will
receive prioritization of replacement, rehabilitation, and repair recommendations.
Based on the 2024 report, there are a total of three bridges that require a wearing
surface/deck repair/upgrades. The 42nd Ave S Bridge Replacement project is
currently under design and anticipated to start construction in 2027. The project
will replace a 75+ year old structure that has structural damage due to an over
height freight truck strike resulting in restricting the bridge to one way traffic. The
project currently has local, state, and federal funding grants to complete the
replacement.
Performance Measures
The bridges in the City will continue to be inspected and analyzed for future
repairs to extend the life of the structures.
Lead Points
of Contact
Sherry Edquid
Partner Points
of Contact
King County
Flood Control
District
Hazards Mitigated /
Goals Addressed
Upgrading levees to
provide 500 year flood
protection and repairing
the Fort Dent Levee.
Funding Sources
and Estimated Costs
King County Flood
Control. District
Strategy Vision/Objective
Update and improve the following levees: Tukwila 205, Tukwila South and
Desimone through new floodwalls and setback or raising of the existing earthen
levees to protect the City of Tukwila by raising these levees to 500-year flood.
protection plus 3 feet of freeboard. . Repair a portion of the Fort Dent Levee
where the bank has eroded and setback the levee. Note: This is just a repair and
will not add additional flood protection.
35 City of Tukwila Hazard Mitigation Plan
Page 26
Mitigation Strategy
By prioritizing the Tukwila 205 Levee improvements in an upstream to
downstream direction, the percent of landprotected steadily increases over time. If
construction were to instead progress downstream to upstream, levee
failure could occur upstream of newly raised levees, and therefore flood the land
area behind the improved levee section. For alternative analysis, design, and
construction prioritization, the Tukwila 205 Levee has been
divided into three main segments that correspond with the three Tukwila capital
improvement projects identified in the Green River SWIF, then with further
subdivision of each of these segments into two or three
smaller subsegments. Prioritization is also informed by prior analyses of the
existing Tukwila 205 Levee system that evaluated Green River water surface
elevations and levee overtopping risk, scour, and geotechnical
levee stability. The King County Flodd Control District is beginning design on the
Desimone Levee which was previously damaged. In the meantime there is an
emergency action plan in place should the Auburn USGS gage reach 10,000 cfs.
2-Year
Objectives
Repair and
setback the
Fort Dent
Levee.
Certify the
Tukwila 205
Levee with
FEMA.
5-Year
Objectives
Upgrade and
setback the
Gunter and
Desimone
Levee
Long -Term Objectives
Upgrade the Ratolo upper, middle and
lower levees and Christensen Road levee
Implementation Plan/Actions
The City of Tukwila sent a letter to the King County Flood Control District (FCD)
on May 1, 2019 and requested that FCD include budgets to reconstruct the
Tukwila 205 levees within the next ten (10) years based on NHC report findings
that the majority of the levee system in its current condition cannot be accredited
to provide 100-year flood protection. However, the SQRA by the Army Corps of
Engineers did recommend accreditation of the levee which the City is currently
pursuing certifying the levee with FEMA.
The existing Tukwila 205 Levee must be updated and improved through new
floodwalls and setback or raising of the existing earthen levees to protect the City
of Tukwila from flooding. The Green River System -Wide Improvement
Framework (SWIF) declared the level of protection standard as the 500-year flood
event plus three feet of freeboard. As important as the freeboard standard, the
levees also must meet factors of safety for geotechnical stability under a variety of
conditions including flood induced scour, drawdown, and seismic
events.
The proposed priority sequence for construction of these flood protection
improvements generally starts at the upstream end of the Tukwila 205 Levee, near
river mile 16.7, and then proceeds downstream to near river mile 12.4 (see previous
map). Upstream of the Tukwila 205 Levee, near South 200th Street, there are
existing levees that currently provide 100-year level of flood protection (this
includes the Frager Lowest Levee between the Tukwila 205 Levee and South 200th
Street). The Tukwila 205 Levee will tie into these 200th Street levees,
which also need to be improved in order to provide 500-year event plus three feet
City of Tukwila Hazard Mitigation Plan
Page 27 36
Performance Measures
Have our levees meet the protection standard.
37 City of Tukwila Hazard Mitigation Plan
Page 28