HomeMy WebLinkAbout2007 Shoreline Master Program Update - Shoreline Restoration Plan
CITY OF TUKWILA
Shoreline Master Program Update
Shoreline Restoration Plan
Prepared for: May 2007
City of Tukwila
Ecology Grant #G0600234
Tukwila Shoreline Restoration Planning – SMA Grant No. 0600234
May 2007 i
TABLE OF CONTENTS
1.0 Introduction........................................................................................................................1
1.1 Regulatory Background................................................................................................................1
1.2 Defining Restoration.....................................................................................................................3
2.0 Restoration Planning.........................................................................................................4
2.1 Restoration Framework ................................................................................................................4
2.2 Assessment of Functions..............................................................................................................6
2.2.1 Watershed Context and Shoreline Modifications...................................................................................6
2.2.2 Habitat and Species................................................................................................................................6
2.2.3 Land Use................................................................................................................................................7
2.2.4 Altered Ecosystem Processes.................................................................................................................7
2.3 Existing Plans and Programs........................................................................................................9
2.3.1 Regional.................................................................................................................................................9
2.3.2 City ......................................................................................................................................................10
2.4 Completed Projects.....................................................................................................................10
3.0 Restoration Opportunities...............................................................................................12
3.1 Potential Projects and Restoration Priorities ..............................................................................12
4.0 Policy Development..........................................................................................................19
5.0 Implementation................................................................................................................20
5.1 Funding and Partnership Opportunities......................................................................................21
5.1.1 Puget Sound Action Team...................................................................................................................21
5.1.2 Salmon Recovery Funding Board (SRFB)...........................................................................................21
5.1.3 King Conservation District..................................................................................................................21
5.1.4 Natural Resource Damage Assessment Funds.....................................................................................22
5.1.5 King County Flood Control District ....................................................................................................22
5.2 Timelines and Benchmarks.........................................................................................................22
5.3 Mechanisms and Strategies for Effectiveness ............................................................................23
6.0 Conclusions.......................................................................................................................24
7.0 References.........................................................................................................................25
8.0 Attachments......................................................................................................................27
List of Tables
Table 1. Restoration Planning Structure........................................................................................4
Table 2. General Restoration Potential within the Shorelines of Tukwila. ................................... 8
Table 3. Completed Restoration Projects in Tukwila................................................................... 11
Table 4. Potential Restoration Projects and Initial Project Ranking............................................ 14
List of Figures
Figure 1. Mitigation Versus Restoration in Shoreline Master Programs (Source: Department of
Ecology).................................................................................................................................. 2
Figure 2. Schematic View of Overall Restoration Framework (based on Palmer et al. 2005)...... 5
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1.0 INTRODUCTION
The Green/Duwamish River is a central feature in the City of Tukwila. The Green/Duwamish
River has long been an important nexus between upland freshwater and marine saltwater
environments, as well as a focus area for historical land use and urban development. The
Shoreline Management Act (SMA or the Act) (RCW 90.58) is charged with balancing how
shorelines should be developed, protected, and restored. The Act has three broad policies or
mandates; it strives to: 1) encourage water-dependent uses, 2) protect shoreline natural resources,
and 3) promote public access. Restoration planning is an important component of the
environmental protection policy of the Act.
This report supports the development of a restoration element to the City of Tukwila’s Shoreline
Master Program (SMP), originally adopted in 1974. The SMP is being updated to comply with
the SMA requirements (RCW 90.58), and the state’s SMP guidelines (Washington
Administrative Code [WAC] 173-26, Part III), which went into effect in 2003.
The SMP guidelines require that local governments develop SMP policies that promote
"restoration" of impaired shoreline ecological functions and a “real and meaningful” strategy to
implement restoration objectives. The City’s shoreline inventory and characterization report
(ESA Adolfson, 2006) identifies which shoreline ecological functions and ecosystem processes
have been impaired. Local governments are further encouraged to contribute to restoration by
planning for and supporting restoration through the SMP and other regulatory and non-regulatory
programs.
This report provides a framework to:
1. Identify primary goals for ecological restoration of the Green/Duwamish ecosystem;
2. Identify how restoration of ecological function can be accomplished;
3. Suggest how the SMP update process may accomplish the restoration of impaired
shoreline functions associated with the Green/Duwamish ecosystem; and
4. Prioritize restoration projects so that the highest value restoration actions may be
accomplished first.
1.1 Regulatory Background
The state has directed local governments to develop SMP provisions “…to achieve overall
improvements in shoreline ecological functions over time when compared to the status upon
adoption of the master program.” This overarching goal is accomplished primarily through two
distinct objectives:
1. Protection of existing shoreline functions through regulations and mitigation
requirements to ensure “no net loss” of ecological functions from baseline environmental
conditions; and
2. Restoration of shoreline ecological functions that have been impaired from past
development practices or alterations.
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This distinction is illustrated in Figure 1. below.
Figure 1. Mitigation Versus Restoration in Shoreline Master Programs (Source:
Department of Ecology)
The concept of no net loss of shoreline ecological function is embedded in the Act and in the
goals, policies and governing principles of shoreline guidelines and other federal and state
environmental protections (e.g., the Clean Water Act). Washington’s general policy goals for
shorelines of the state include the “protection and restoration of ecological functions of shoreline
natural resources.” This goal derives from the Act, which states, “permitted uses in the shoreline
shall be designed and conducted in a manner that minimizes insofar as practical, any resultant
damage to the ecology and environment of the shoreline area.” Furthermore, the governing
principles of the guidelines clarify that protection of shoreline ecological functions is
accomplished through the following (WAC 173-26-186):
• Meaningful understanding of the current shoreline ecological conditions,
• Regulations and mitigation standards that ensure that permitted developments do not
cause a net loss of ecological functions,
• Regulations that ensure exempt developments in the aggregate do not result in net loss of
ecological functions,
• Goals and policies for restoring ecologically impaired shorelines,
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• Regulations and programs that fairly allocate the burden of mitigating cumulative
impacts among development opportunities, and
• Incentives or voluntary measures designed to restore and protect ecological functions.
It is important to note that the restoration planning component of the SMP is focused on
voluntary mechanisms, not regulatory provisions. Restoration planning is focused on economic
incentives, available funding sources, volunteer programs, and other programs that can
contribute to a no net loss strategy. However, the restoration framework developed for these
non-compensatory mitigation projects can also be applied to compensatory mitigation projects.
In this way, all efforts to improve ecosystem functioning are coordinated, and will be designed to
work together.
1.2 Defining Restoration
There are numerous definitions for “restoration” in scientific and regulatory publications.
Specific elements of these definitions often differ, but the core element of repairing damage to an
existing, degraded ecosystem remains consistent. In the SMP context, the WAC defines
“restoration” or “ecological restoration” as:
“…the reestablishment or upgrading of impaired ecological shoreline processes or
functions. This may be accomplished through measures including, but not limited to,
revegetation, removal of intrusive shoreline structures and removal or treatment of toxic
materials. Restoration does not imply a requirement for returning the shoreline area to
aboriginal or pre-European settlement conditions” (WAC 173-26-020(27)).
Using the WAC definition of restoration in regards to state shorelines, it is clear the effort should
be focused on specific shoreline areas where natural ecological functions have been impaired or
degraded. The emphasis in the WAC is to achieve overall improvement in existing shoreline
processes or functions, where functions are impaired. Therefore, the goal is not to restore the
shoreline to historically natural conditions, but rather to improve on existing, degraded
conditions. In this context, restoration can be broadly implemented through a combination of
programmatic measures (such as surface water management; water quality improvement; public
education) and site-specific projects (such as setback levees or riparian plantings). It is
important to note that the guidelines do not state that local programs should or could require
individual permittees to restore past damages to an ecosystem as a condition of a permit for new
development (Ecology, 2004). The restoration planning element therefore focuses on the City as
a whole rather than parcel by parcel, or permit by permit.
Table 1 below summarizes the key elements included in restoration planning within the context
of an SMP update under the state’s current guidelines (WAC 173-26-201(2)(f)). These key
elements provide the organization and content for this report.
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Table 1. Restoration Planning Structure
Key elements for the shoreline restoration planning
process WAC 173-26-201(2)(f)
Section in this report
Identify degraded areas, impaired ecological functions, and
sites with potential for ecological restoration.
Assessment of Functions (Section 2.2);
Restoration Opportunities (Section 3)
Establish overall goals and priorities for restoration of
degraded areas and impaired ecological functions.
Restoration Priorities (Section 3.2);
Policy Development (Section 4)
Identify existing and ongoing projects and programs that are
currently being implemented which are designed to
contribute to local restoration goals (such as capital
improvement programs (CIPs) and watershed planning
efforts (WRIA habitat/recovery plans).
Existing Plans and Programs (Section
2.3);
Potential Projects (Section 3.1)
Identify timelines and benchmarks for implementing
restoration projects and programs and achieving local
restoration goals.
Implementation (Section 5)
Provide for mechanisms or strategies to ensure that
restoration projects and programs will be implemented
according to plans and to appropriately review the
effectiveness of the projects and programs in meeting the
overall restoration goals (e.g., monitoring of restoration
project sites).
Implementation (Section 5)
Identify additional projects and programs needed to achieve
local restoration goals, and implementation strategies
including identifying prospective funding sources for those
projects and programs.
Restoration Opportunities (Section 3);
Funding and Partnership Opportunities
(Section 5.1)
2.0 RESTORATION PLANNING
The guidelines for the SMP process direct that local shoreline master programs shall include
“goals, policies and actions for restoration of impaired shoreline ecological functions.” Under
the guidelines, restoration planning has a purpose distinct from development regulations and
mitigation standards. “The guidelines expressly focus restoration requirements on the use of
master program policies, as opposed to development regulations” (Ecology, 2004). Therefore, to
develop specific restoration goals and policies for Tukwila’s SMP, an overall restoration
framework was considered to maintain consistency with an approach to restoration currently
recommended at the national level. This restoration framework includes elements that go beyond
the traditional no net loss philosophy to target a long-term improvement in a broad base of
ecosystem functions where feasible in the City of Tukwila.
2.1 Restoration Framework
Significant national attention has been applied recently to the development of an approach to
restoring riverine ecosystems that will more consistently result in long-term improvement in
ecosystem functioning (Brinson, 1993, Kondolf, 1995, Palmer et al, 2005, Bernhardt et al, 2005).
The National River Restoration Science Synthesis project recently focused efforts on developing
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both: 1) a database of existing and proposed river restoration projects; and 2) criteria to
consistently determine if a restoration is successful (Palmer and Allan, 2006). This work is
intended to provide a consistent restoration approach across jurisdictions and to improve the
probability of future success by learning from existing river restoration projects.
These national efforts have resulted in recent publications of a recommended approach to river
restoration. This approach is synthesized in Figure 1, below, modified for use within this
restoration framework. The approach has three phases: (1) Decision, (2) Design and
Implementation, and (3) Monitoring and Assessment. This framework is offered here to provide
the following:
• Background and insight into how current approaches to ecosystem restoration have been
developed;
• A way to consider how to integrate new information as it comes available; and
• A basis for integrating the City’s efforts into regional efforts.
Figure 2. Schematic View of Overall Restoration Framework (based on Palmer et al. 2005)
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2.2 Assessment of Functions
Shoreline restoration planning begins with the identification of “degraded areas” or areas with
“impaired ecological functions.” The assessment of existing degraded areas and/or functions
relies heavily on the City of Tukwila Draft Shoreline Inventory and Characterization Report
(ESA Adolfson, 2006). The City’s inventory and characterization examined riverine and
estuarine ecosystem processes that maintain shoreline ecological functions; and identified
impaired ecological functions. Key findings of the inventory and characterization are
summarized below.
2.2.1 Watershed Context and Shoreline Modifications
The City of Tukwila is situated in the Puget Sound Lowlands at the transition from the fresh
water Green River to the tidally influenced Duwamish estuary ecosystem. Tukwila includes
approximately 12.5 miles of the Green/Duwamish River. The Green River basin is part of the
Green/Duwamish Water Resource Inventory Area (WRIA 9).
Historically, the Green/Duwamish River drained a significantly larger area than it does today.
River course changes and major engineering projects in the early part of the 20th century resulted
in both the White and Cedar Rivers being diverted to neighboring basins. As a result, the overall
freshwater discharge in the Green/Duwamish River has been reduced to around a third of the
pre-diversion era. The Green/Duwamish has undergone extensive modifications as part of past
river management with the intent of reducing channel migration and limiting the extent and
duration of valley flooding.
Levees and/or revetments have been constructed along the majority of the Green/Duwamish
River through the City of Tukwila to increase bank strength and reduce flooding. In addition,
flows within the Green/Duwamish River have been significantly modified by the construction of
the Howard A. Hansen Dam and installation of water diversions. These modifications have
significantly reduced the severity of floods that historically covered much of the valley bottom.
The condition of the current system of levees and revetments is a growing source of concern for
King County and the cities involved, as many of the levees are aging and would not meet current
standards for either flood conveyance or stability.
2.2.2 Habitat and Species
The Green/Duwamish River within the City of Tukwila provides important habitat for several
fish and some wildlife species, such as osprey. The aquatic environment within the channel is an
important corridor located at the transition from the freshwater riverine environment to tidal
estuarine environment of Elliot Bay. Almost every species of anadromous fish migrates through
this transition zone. The entire length of the Green/Duwamish River within the City of Tukwila
has been declared “critical habitat” for the Chinook salmon and bull trout. Both species are
listed as threatened under the Federal Endangered Species Act.
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The transition zone between fresh and salt water has effectively been pushed upstream from its
historic location due to: (1) a significant reduction (70%) of fresh water flowing into the
Duwamish estuary (owing to the diversion of the White and Cedar/Black Rivers), (2) channel
dredging, and (3) reduction of flows as a result of the Howard A. Hanson dam. The
establishment of heavy industrial uses in the transition zone has replaced wetlands with
impervious surfaces, and the stream banks have been replaced by levees and other armoring,
eliminating slow-moving flows through edge habitat and creating unrestrained downstream
flows. Spatial structure, residence time, and the habitat available for refugia and rearing
functions in the Duwamish estuary have therefore been reduced and constrained. High densities
of fish have been observed utilizing what is left of this specific habitat. At the watershed scale,
overall increases in salmonid survival rates are dependent on the availability of sufficient
transition zone habitat to accommodate fish while they adjust from fresh to salt water (WRIA 9
Steering Committee, 2005).
Modifications to the river system have resulted in reduced levels of ecosystem functioning,
including hydrology, water quality, riparian habitat, and in-stream habitat. Changes to hydrology
focus on modified flow regime due to dam construction, diversion, and urban development.
River management and levees have reduced the connection between the rivers and their
floodplains, changing the spatial extent of habitats, and increasing the potential for negative
water quality impacts. Disturbances to the channel banks have resulted in areas that are
dominated by non-native invasive species. Wood, in the form of riparian trees and in-channel
wood, is generally lacking through the system, which negatively impacts riparian and aquatic
habitats.
2.2.3 Land Use
The majority of the upper Green/Duwamish watershed, outside of the city limits, is in managed
forestland, parkland, or designated wilderness areas. Agricultural land covers much of the higher
river within the Green River gorge. The Kent-Auburn Valley is a transitional area between the
forest and agricultural activities upstream to the highly developed residential, industrial and
commercial development in the cities of Kent, Tukwila, and Seattle downstream in the Lower
Green / Duwamish River Valley.
Within the valley, industrial, commercial, and residential land uses dominate the former Green
River floodplain in the vicinity of Tukwila. South of the city, commercial and
warehouse/industrial land uses dominate on the right bank in the City of Kent, with agricultural
fields on the left bank within the Tukwila South annexation area. Commercial development is
prevalent between the southern city boundary and I-405. Residential development dominates
between I-405 and the I-5 Bridge. North of the I-5 Bridge to the turning basin, residential uses
give way to commercial uses. The upper turning basin, located at river mile 5.8, is the southern
boundary of the predominantly industrial area that extends to the northern city limit.
2.2.4 Altered Ecosystem Processes
Key findings regarding current levels of ecosystem functioning within the lower
Green/Duwamish ecosystem are reported in Chapter 5 of the City of Tukwila Draft Shoreline
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Inventory and Characterization Report (ESA Adolfson, 2006). The inventory report identified
key ecosystem processes, and provided a qualitative assessment of their levels of functioning at
both a watershed and city reach scale. Key ecosystem functions identified in the Inventory, their
level of alteration, and potential restoration actions are summarized below.
Table 2. General Restoration Potential within the Shorelines of Tukwila.
Function
Category Function Alterations to natural
functioning
Potential Restoration Action
within the City
Hydrologic
Channel -
Floodplain
Interaction
Presence of flood protection
structures (e.g., levees, river
bank revetments, flood gates)
and significant fill and
development along the shoreline
limit channel-floodplain
interactions in Tukwila.
1. Modify current levees and
revetments to increase channel and
floodplain interaction;
2. Excavate back or side channels;
Hydrologic
Upland
sediment
generation
Fine sediment contribution to
the river is increased due to
build-up and wash-off from
surrounding urban land uses.
1. Implement enhanced stormwater
BMPs for fine sediment removal in
stormwater runoff.
Water
Quality
Retention of
particulates
Levees and revetments are
virtually continuous along the
riverbanks, limiting the potential
to retain particulates in the
fluvially dominated reaches.
Particulates, including sediment,
are retained in the tidally
dominated reaches, as
evidenced by the need to
dredge the estuary turning
basin.
1. Modify current levees and
revetments to increase channel and
floodplain area;
2. Install native riparian species to
increase bank roughness.
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Function
Category Function Alterations to natural
functioning
Potential Restoration Action
within the City
Water
Quality Nutrient Cycling
As channel-floodplain interaction
was reduced, the channel
became a conduit for nutrients,
offering little opportunity for
contact time with soils.
1. Increase riverine wetland area;
2. Install native riparian plant
species.
3. Set back banks (revetments and
levees).
LWD and
Organics
Maintain
Characteristic
Plant
Community
The majority of the shoreline
within the City of Tukwila is
currently dominated by non-
native invasive weed species
(Himalayan blackberry, reed
canary-grass, and Japanese
knotweed). Some higher quality
areas of cottonwood, alder, and
willow exist in riparian areas
bordering open space, parkland,
and residential zones.
1. Remove invasive plants and
install native riparian species;
2. Incorporate LWD into bank
stabilization and restoration projects;
3. Institute programmatic weed
control activities along shoreline.
4. Promote bioengineering
techniques for shoreline stabilization
projects.
LWD and
Organics: Source of LWD
Despite the lack of many
sources for LWD, there are
some large cottonwoods and big
leaf maples occur along the
levees and revetment system.
1. Install native riparian species;
2. Incorporate LWD into bank
stabilization and restoration projects.
As noted in the inventory and characterization report and summarized above, many of the
alterations to shoreline functions and ecosystem processes in the Green/Duwamish River are due
to watershed scale issues within the upper watershed which cannot be fully restored or addressed
in the lower river section through Tukwila. However, hydrologic, water quality, and habitat
restoration measures in the City do have the potential to improve the overall functioning of this
important section of Green/Duwamish River ecosystem at the transition from fresh to salt water.
2.3 Existing Plans and Programs
2.3.1 Regional
The importance of the Green/Duwamish ecosystem within the Puget Sound has resulted in
significant focus on this area in terms of restoration potential. With the federal listing of
Chinook and bull trout as endangered species, watershed planning in the region (e.g., WRIA 9)
has focused on developing a Salmon Habitat Plan (WRIA 9, 2005), to which the City of Tukwila
is a party. The plan establishes goals, objectives, and programmatic and site specific actions to
address restoration of habitat critical to salmon species in the Green/Duwamish watershed. In
general, the approach used by the regional entities around Tukwila (e.g. WRIA 9, King County)
appears to be consistent with the overall national restoration framework in the sense that the
proposed projects address a broad base of ecosystem functions.
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To allow for the implementation of the restoration goals within a watershed context, it is
imperative that the City of Tukwila continue to coordinate its actions with other regional entities.
These entities often focus specifically on restoration (e.g., Puget Sound Action Team), or have a
broad mandate to address the Green/Duwamish system (e.g., King County, Green River Flood
Control Zone District).
2.3.2 City
Tukwila has already engaged in the greater regional restoration effort for the Green/Duwamish
River. The City Council has ratified the WRIA 9 Plan and contributes resources to maintain
operating staff. Tukwila has worked within the larger Green/Duwamish River Ecosystem
restoration project to acquire properties that are either currently functioning (Cecil B. Moses
park), or have the potential for restoration (North Winds Weir). WRIA 9 and other regional
partners are currently working together to monitor baseline conditions (e.g., Anchor, 2004;
Pentec, 2004; Terralogic and Landau, 2004).
2.4 Completed Projects
Several projects have already been completed in the Green/Duwamish River. These projects
provide an excellent opportunity to learn about what river restoration measures are the most
effective. For example, it appears that the back channel that was excavated at Codiga Farm
provides important habitat for migrating juvenile fish (Corps Seattle District, 2004). These
projects and their current status are shown below in Table 3, listed by river mile (RM). The
general location of these projects in Tukwila is shown on Map 1.
Tukwila Shoreline Restoration Planning – SMA Grant No. 0600234 February 2007 11 Table 3. Completed Restoration Projects in Tukwila Map Identifier Project Name Project Goals & ObjectivesCurrent Status/Stage Lead Agency or Agencies Funding River Mile C-1 Kenco Marine intertidal habitat restoration site (also referred to as the Turning Basin #3 Project) To restore the resources affected by releases of hazardous substances from CSOs and storm drains - with restoration of salmonid habitat being a priority. Completed project but maintenance and monitoring unknown at this time. Currently owned by Muckleshoot Indian Tribe. NOAA Fisheries did the contracting work for the project. Seattle, King County, and Ecology also involved. 1991 settlement moneys from suit filed by the United States against the City of Seattle and King County for “alleged injuries to natural resources”. RM 5.3 C-2 Coastal America Turning Basin restoration / enhancement site Clean up area that was developed and plant with native riparian and brackish marsh vegetation Completed project. Maintenance is ongoing as volunteer effort. Corps of Engineers RM 5.4 C-3 Cecil B. Moses Park off-site channel estuary wetland, intertidal habitat restoration site. Create off-channel, shallow water habitat in the transition zone to restore intertidal marsh. Completed project, maintenance schedule unknown. Monitoring program is in effect. Elliot Bay/Duwamish Restoration Panel (2000) Agency funded, 1991 settlement moneys from suit filed by the United States against the City of Seattle and King County for “alleged injuries to natural resources”. RM 6.2 Left bank C-4 Codiga Farm off-channel, estuary wetland site Create off-channel juvenile fish refuge and wetland habitat including deep- and shallow-water areas. Completed project, future improvement is being considered. The maintenance & monitoring program is incomplete. Corps of Engineers Long-term funding. Tukwila will be responsible for maintenance & monitoring RM 8.5 Right bank C-5 Desimone Levee (portion that has been repaired) Set back existing levee, increase bank strength; include LWD at toe to provide instream habitat Completed in phases in 1999 and 2002 King County Agency funded RM 15.4 Right bank 1,300 feet
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It is important to note that the monitoring and maintenance aspects of several of these completed
projects are not being fully executed. Implementation of effective monitoring and maintenance
of these projects is needed to match current national guidance for restoration and to maximize
the potential for restoration success.
3.0 RESTORATION OPPORTUNITIES
Based on the key ecosystem functions that are currently altered, there appear to be two specific
types of restoration actions that will most benefit the Green/Duwamish ecosystem in Tukwila.
These actions are intended to boost the levels of ecosystem functioning as part of a self-
sustaining ecosystem that will limit the need for future manipulation. While these projects are
intended to restore many ecosystem functions, the restoration activities will occur in the highly-
urban valley bottom, and as a result, cannot fully achieve pre-disturbance channel conditions. In
addition, some restoration actions must occur at the watershed scale, which will restore
ecosystem functions that cannot be addressed solely within Tukwila.
1. Enlarging channel cross-sectional area. This action will increase flood storage, allow
for more stable levees, restore floodplain area, provide a larger intertidal zone in this
important transitional area, and provide a more natural transition from aquatic to upland
habitats. This action could include the use of setback levees and revetments, and the
excavation of historic fill or floodplain materials to create back channels.
2. Enhance existing habitats. This action will improve the functioning of the existing
aquatic, riverine wetland, and riparian habitats that currently exist along the
Green/Duwamish River. These actions could include the removal of non-native invasive
vegetation, installation of native riparian vegetation, and installation of LWD below
ordinary high water.
3.1 Potential Projects and Restoration Priorities
Significant past work has occurred to identify specific restoration projects within the shorelines
of Tukwila (Pentec, 2004, Anchor 2003, WRIA 9, 2005 etc.). Many of these projects were
identified in the Inventory and Characterization Report, and are described below. Most of the
restoration projects are part of ongoing restoration planning through the WRIA 9 watershed
planning process. Table 4 includes a project description and notes the current status of each
project. The project number correlates to those locations shown on Maps 1 through 4 in Section
8., Attachments.
Opportunities exist to enhance riparian vegetation along the majority of the Green/Duwamish
River, as mentioned in previous reports (e.g., Anchor 2003). Since these opportunities are so
ubiquitous, they are not specifically addressed in Table 4.
To aid the City in developing an internal ranking system, a preliminary qualitative (high,
medium, low) project ranking system is employed.
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High priority projects will typically:
• Address both hydrologic and habitat ecosystem functions;
• Have opportunity for multiple funding sources;
• Include freshwater tributary channels; and/or
• Not require additional property acquisition.
Medium priority projects will typically:
• Address limited ecosystem functions; and
• Be eligible for multiple funding sources, and/or require property acquisition.
Low priority projects will typically:
• Only focus on habitat enhancement;
• Will be used as mitigation to offset impacts elsewhere; or
• Not be eligible for multiple funding sources.
This ranking system is applied to the projects that have been proposed to-date, as described in
Table 4.
Tukwila Shoreline Restoration Planning – SMA Grant No. 0600234 May 2007 14 Table 4. Potential Restoration Projects and Initial Project Ranking Project Name / Location Project Description / Goals Ecosystem Processes / Shoreline Functions Addressed Current Status / Funding Lead Agency or Agencies Potential for Success Ranking Notes 1 Shallow water habitat creation - Hamm Creek stream and estuary restoration site RM 4.7-5.5 Restore intertidal mudflats and channel edge habitats to create low velocity and/or shallow water habitat. Rehabilitate riparian areas. Combined area totaling 10 acres. Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Targeted land area is not yet available for completion of project Funding not yet identified King County/WRIA 9 (2005,Project DUW-11) Good Similar to Codiga Farm in geomorphic context Medium High ecological priority; land would need to be acquired 2 Area to south of Coastal America Turning Basin restoration/enhancement site RM 5.4 Add to restoration that occurred under this project – south side of inlet, clear invasive vegetation, etc. Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Exploratory; Property acquisition needed Funding not yet identified To Be Determined Good Similar to Codiga Farm in geomorphic context Medium Addresses multiple ecosystem functions; would expand existing restoration, land would need to be acquired 3 Duwamish Riverbank Stabilization at S. 104th St. RM 5.8 Right bank Stabilize eroding bank, regrade, restore 400 lf of riparian vegetation Fluvial Sediment Transport Maintain Characteristic Plant Community CIP Project #94-DR05 Funding not identified yet To Be Determined Good Similar to previous bioengineering projects Medium Addresses limited ecosystem functions, does not increase channel area; land would need to be acquired 4 North Wind Weir off-site channel estuary wetland (Site #1), intertidal habitat restoration site. RM 6.3 Right bank Create two acres of off-channel, shallow water habitat in the transition zone to restore intertidal marsh area. Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community First phase of soil remediation is complete. Construction for fish and wildlife habitat is pending but scheduled for 2007 Project has initial funding to start construction King County/WRIA 9 (2005,Project DUW-10) Good Similar to Codiga Farm in geomorphic context High Addresses multiple ecosystem functions, land already acquired; some construction funds secured 5 Bank restoration & revetment setback RM 5.5 - 6.6 Left bank Protect & improve riparian vegetation. Remove existing bank armor and fill and increase area within the estuarine transition zone. Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Schedule not yet established Funding not yet identified King County/WRIA 9 (2005, Project DUW-9) Good Similar to Codiga Farm in geomorphic context Medium Addresses multiple ecosystem functions; land would need to be acquired 6 Riverton Creek channel and tidal wetland enhancements RM 6.6 Restore tributary access by removing fish passage barriers and modifying stream mouth area. Rehabilitate riparian and wetland slough areas in their current locations. Channel Floodplain Interaction Retention of Particulates Nutrient cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD Coordination with City and WSDOT in progress Funding not yet identified King County/WRIA 9 (2005, Project DUW-8) CIP# 98-DR06 Fair Removal of fish barrier will require careful design. High Addresses multiple ecosystem functions, land already in public ownership; opportunity to team with WSDOT
Tukwila Shoreline Restoration Planning – SMA Grant No. 0600234 May 2007 15 Project Name / Location Project Description / Goals Ecosystem Processes / Shoreline Functions Addressed Current Status / Funding Lead Agency or Agencies Potential for Success Ranking Notes 7 Shallow water habitat creation RM 5.5 - 7.0 Restore intertidal mudflats and channel edge habitat to create low velocity areas adjacent to river channel Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community No specific project is planned Phased project, funding not yet identified King County/WRIA 9 (2005, Project DUW-7) Good Similar to Codiga Farm in geomorphic context Medium Addresses multiple ecosystem functions; land would need to be acquired 8 Duwamish Gardens, off-channel habitat area (formerly called the Carasino property) RM 7 Right bank Create 2.1 acres of off-channel fish refuge habitat Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Land is available for the project and funding application has started Funding to purchase site is being sought King County/WRIA 9/City of Tukwila (2005, Part of Project area DUW-7 CIP Project #06-DR02 Good Similar to Codiga Farm in geomorphic context High Addresses multiple ecosystem functions, $726,000 in grant funds acquired to-date, land can be acquired; eligible for grant funding. 9 S. 115th St. Bank restoration and revetment setback RM 6.9 – 7.2 Right bank Remove existing armor, reshape and revegetate the river bank Same location as 10, below, but different strategy. Fluvial Sediment Transport Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community City owns eastern portion Funding unknown King County/WRIA 9 & City of Tukwila (2005, Project DUW-6) Good Similar to previous bioengineering projects Medium Addresses limited ecosystem functions; 10 Duwamish Riverbank Stabilization near S. 115th St RM 6.9 – 7.2 Right bank Stabilize 1200 lf, regrade and stabilize with bioengineering, maintain native mature trees and shrubs on 3700 lf Fluvial Sediment Transport Maintain Characteristic Plant Community City owns eastern portion Funding not identified yet Tukwila CIP Project #94-DR09 Good Similar to previous bioengineering projects (e.g. Desmoine levee) Low Does not set levee back (see Map ID 9 for alternative) 11 42nd Ave. S. Bank restoration RM 7.1 – 7.9 Improve riparian habitat throughout this segment. Relocate a water main pipe to reconfigure the east bank and allow for a low vegetated bench to be constructed. Add large woody debris component to the channel. Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD Schedule not yet established Funding not yet identified King County/WRIA 9 & City of Tukwila (2005, Project DUW-5) Fair Water line constrains design options Medium Addresses limited but important ecosystem functions 12 Potential estuary restoration & enhancement at mouth of Southgate Creek RM 8 Provide fish refuge area Transition from fresh to salt water Schedule not yet established Funding not yet identified City of Tukwila, land acquisition needed. Fair Located at dynamic area at end of Southgate Creek Medium Addresses limited ecosystem functions;
Tukwila Shoreline Restoration Planning – SMA Grant No. 0600234 May 2007 16 Project Name / Location Project Description / Goals Ecosystem Processes / Shoreline Functions Addressed Current Status / Funding Lead Agency or Agencies Potential for Success Ranking Notes 13 Bank restoration & revetment setback RM 8.2 – 8.9 Left bank Reshape existing revetment and relocate Green River Trail to create slow water areas, add native riparian plants and large woody debris Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD Schedule not yet established Funding not yet identified King County/WRIA 9 (2005, Project DUW-3) Good Similar to Codiga Farm in geomorphic context Medium Addresses multiple important ecosystem functions; funding not started 14 Shallow water habitat creation RM 7.0 – 11.0 Both banks Create a minimum of 15 acres of new off-channel shallow water / marsh habitat with associated riparian vegetation Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD Schedule or project plan not yet established. Property acquisition may be necessary Phased project, funding not yet identified King County/WRIA 9 (2005, Project DUW-1) Good Similar to Codiga Farm in geomorphic context Medium Addresses multiple ecosystem functions; requires property acquisition 15 Create off-channel, estuary wetland on right bank RM 9.9 -10.3 Enhance riparian areas & create off-channel shallow-water refuge habitat. Side channel construction is possible. Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD Schedule or project plan not yet established. Property acquisition required. Funding not yet identified King County/WRIA 9 (2005, Project DUW-2) Good Medium Addresses multiple ecosystem functions; requires property acquisition 16 Foster Golf Course Riverbank Improvements Approximately RM 10 LWD/revegetation along riparian edge as mitigation for USACOE requirement to remove trees from levees. Maintain Characteristic Plant Community Source of LWD Scheduled for 2007; CIP Project #03-PK06 Funding not identified City of Tukwila Good Low Site intended for use as mitigation, therefore should not be a focus for restoration efforts 17 Improve confluence of Black River and Green River by restoring riparian corridor and creating emergent marsh RM 11 Replace non-native vegetation with native species on the banks of the Green and Black rivers. Create emergent marsh area and incorporate large woody debris to increase nutrient productivity and improve salmonid fish refuge and rearing. Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD Conceptual plan Funding not yet identified King County/WRIA 9 (2005, Project LG-18), ERP project Good Medium Addresses multiple ecosystem functions
Tukwila Shoreline Restoration Planning – SMA Grant No. 0600234 May 2007 17 Project Name / Location Project Description / Goals Ecosystem Processes / Shoreline Functions Addressed Current Status / Funding Lead Agency or Agencies Potential for Success Ranking Notes 18 Ft. Dent Park riparian area enhancement on east bank and levee setback RM 11.4 – 11.7 Right bank Setback the existing levee to create a low vegetated bench for low velocity and /or shallow water habitat. Plant native vegetation and add large woody debris. Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD No schedule or project plan established Funding not yet identified King County/WRIA 9 (2005, Project LG-17) Good Medium Addresses multiple ecosystem functions over a limited area 19 Gilliam Creek fish passage improvements and riparian rehabilitation RM 12.5 Left bank Remove existing flood control flap gate from mouth of Gilliam Creek and add fish ladder to restore fish passage but retain flood control. Approximately 2,000 feet of the Creek would be improved by widening the channel, adding spawning gravel, large woody debris, and riparian vegetation. Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Upland sediment generation Maintain Characteristic Plant Community Source of LWD Needs multiple agency coordination. Schedule or project plan not yet established. Funding not yet identified King County/WRIA 9 (2005, Project LG-16), Ecosystem Restoration Project City CIP Project #98-DR05 Fair Requires fish ladder to restore connectivity High Addresses important freshwater tributary and multiple ecosystem functions 20 Nelson Side Channel Off-channel habitat rehabilitation RM 12.5 – 12.65 Connect remnant river channel (Nelson wetland) with river to create off-channel refugia for juvenile fish. Restore river bank by re-sloping river side channel / adjacent levee and planting riparian vegetation. Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Conceptual planning stage Funding not yet identified King County/WRIA 9 (2005, Project LG-15) City CIP Project #03-PK04 Good Similar to Codiga Farm in geomorphic context High Addresses multiple ecosystem functions; conceptual design completed, property in public ownership. 21 Side channel project on riverward side of levee RM 12.8 Potential side channel creation in disconnected floodplain at Riverview Plaza. Create freshwater wetland habitat, flood storage, low velocity / shallow water areas for food production and fish refuge. Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD City-owned land, preliminary conceptual plan Funding not yet identified; coordination with WRIA 9 has begun City of Tukwila. Potential location for restoration and/or off-site wetland mitigation Good Medium Addresses multiple ecosystem functions; does not require property acquisition; coordination with WRIA 9 has begun to pursue eligibility for matching funds. 22 Off-channel and wetland habitat creation RM 12.5 – 13.5 Create an engineered side-channel to connect and enhance approximately 10 acres of wetland. Project would provide floodplain re-connection and juvenile Chinook habitat during peak time rearing and migration. Improve the river banks, enhance wetland areas, and create tributary channels. Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD Schedule or project plan not yet established. Requires participation of public and private landowners Funding not yet identified King County/WRIA 9 (2005, Project LG-14) Good Medium Addresses multiple ecosystem functions; requires property acquisition; could provide significant area 23 Acquisition, levee setback and habitat rehabilitation RM 14.7 – 15.3 Right bank Setback existing levee to widen the river channel, provide a low vegetated bench, install woody debris, and plant native riparian vegetation. Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD Conceptual planning stage. Requires acquisition of river right-of-way just north of Desimone levee setback project. Funding not yet identified King County/WRIA 9 (2005, Project LG-13) Good Medium Addresses limited ecosystem functions, requires property acquisition
Tukwila Shoreline Restoration Planning – SMA Grant No. 0600234 May 2007 18 Project Name / Location Project Description / Goals Ecosystem Processes / Shoreline Functions Addressed Current Status / Funding Lead Agency or Agencies Potential for Success Ranking Notes 24 Desimone Levee Projects 1-3 RM ~14-15 Levee set back projects to repair/replace existing oversteepened levees Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD CIP-level plans Funding unknown King County Flood Hazard Management Plan 2006 Fair River system has potential to be more dynamic in this area Medium Levee setback is less complex in this location since the property is undeveloped at this time; 25 Segale Levee Projects 1-2 RM ~15 Levee set back projects to repair/replace existing oversteepened levees Channel Floodplain Interaction Retention of Particulates Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD CIP-level plans Funding unknown King County Flood Hazard Management Plan 2006 Fair River system has potential to be more dynamic in this area Medium Levee setback is less complex in this location since the property is undeveloped at this time; 26 Acquisition and off-channel habitat rehabilitation – Johnson Creek RM 16 – 17.3 Off-channel wetland mitigation site and restore Johnson Creek and outlet to the River for fish access. Construct juvenile salmonid flood refuge and rearing habitat adjacent to the river. Remove fish passage barriers, re-align Johnson Creek, and re-connect habitats with the river channel. Add shallow water areas, create wetland habitats, and enhance degraded riparian area with native vegetation. Channel Floodplain Interaction Retention of Particulates Upland sediment generation Nutrient Cycling Transition from fresh to salt water Maintain Characteristic Plant Community Source of LWD Conceptual planning stage. Annexation proposal to Tukwila is under review. Funding not yet identified King County/WRIA 9 (2005, Project LG-11), Lead agency to be determined Fair Relocates Johnson Creek Medium Addresses multiple ecosystem functions, requires property acquisition
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4.0 POLICY DEVELOPMENT
The City of Tukwila has been a partner in several projects within the greater Green/Duwamish
River Ecosystem Restoration Project (e.g., North Winds Weir and Codiga Farm property
acquisitions). Both projects are excellent examples of focusing restoration resources and efforts
on projects that address both hydrologic and habitat ecosystem functions.
The initial success of these efforts underscores the importance of the City of Tukwila working
with other national or regional entities to pursue significant restoration opportunities. While the
City may be able to pursue some restoration or enhancement opportunities without regional
partners, these types of projects will typically be smaller scale, lower priority actions (e.g., weed
control, native plantings).
Seven general policies have been identified that the city could use to promote the restoration of
ecosystem functioning within the Green/Duwamish Ecosystem. The policies are not listed in
order or priority.
Policy 1. Identify specific restoration opportunities in or near Tukwila where the City can
support another lead agency.
Policy 1 is intended to allow Tukwila to support restoration efforts throughout the basin. As
noted in the Inventory and Characterization Report, there are some issues, including water
quality, that are better addressed at other points in the watershed. By the time high temperature
river water reaches Tukwila, it is not possible to cool the water sufficiently to have a meaningful
effect on local habitat conditions.
Policy 2. Identify specific restoration opportunities within Tukwila where the City can take the
lead with support from other regional entities.
Policy 2 is intended to continue Tukwila’s support of ecosystem restoration efforts. The
restoration framework and goals presented above provides a preliminary method for the City to
identify high-priority restoration projects. This method is intended to help the city focus its
efforts in an organized way.
Policy 3: Provide incentives to new projects and proposed re-development to preserve additional
area behind existing levees to allow for levee setback and back channel projects.
Policy 3 is intended to provide the city a way to preserve area along the river corridor, and to
provide additional area for future restoration activities. This policy is an incentive-based
approach to preserving the same level of economic development allowed under current zoning
while preserving the opportunity to accomplish effective restoration of the river corridor.
Policy 4. Provide stormwater utility rate incentives and/or new stormwater regulations to
promote enhanced water quality treatment measures.
Policy 4 is intended to improve water quality within the Green/Duwamish River. This is another
incentive-based approach to balance the impacts of new development. If successful, this policy
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could be expanded to address retro-fitting expanded treatment into existing systems. This policy
will also help to acknowledge the connection of areas outside of shoreline jurisdiction to the
shoreline. The recently issued Phase 2 NPDES will require changes in the City’s stormwater
regulations to meet the new requirements and promote improvements in water quality.
Policy 5. Provide monitoring and adaptive management of restoration projects implemented
within the city.
Policy 5 is intended to move the city into a leading role in monitoring and maintaining
restoration projects that occur within the City. It is appropriate for the City to take the lead on
day-to-day maintenance (e.g., maintenance of irrigation systems) and adaptive management of
these restoration sites to ensure that they have the highest potential for success. Monitoring and
maintenance are key elements of the restoration framework, and will be essential to the
continuous improvement for future restoration projects. However, staffing does not currently
exist to support these activities.
Policy 6. Use this restoration framework to integrate compensatory mitigation projects into the
broader restoration vision for the city.
Policy 6 is intended to recognize that future development allowed under the SMP may have
unavoidable adverse impacts to shoreline functions. In those cases, the restoration planning
element of the SMP should help inform development of mitigation.
Policy 7. Continue to work cooperatively with King County, the US Army Corps of Engineers,
and the Federal Emergency Management Agency to resolve Green River levee issues in a
way that enhances shoreline functions to the extent possible.
Policy 7 is intended to recognize that the levees may not currently meet management standards
or flood insurance certification requirements and a variety of other agencies have both
jurisdiction and varying objectives with regard to maintenance and management of the levee
system.
Policy 8. Encourage public involvement in the restoration of the shoreline.
Policy 8 is intended to provide opportunities for the citizens of Tukwila to take part in, and learn
about, the restoration of Tukwila’s shorelines. Example events include: clean-up days, invasive
species removal, native plantings, and monitoring projects. This policy also supports types of
projects that would not score highly on the priority ranking, above.
5.0 IMPLEMENTATION
The implementation portion of restoration planning typically requires more detailed site-specific
information than is available at this time. This section provides an implementation approach
consistent with the restoration framework and guidance for SMP development (WAC 173-26-
201(2)(f)(vi)).
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5.1 Funding and Partnership Opportunities
Funding opportunities for restoration projects include both federal and state grants and legislative
funds administered by state agencies. For potential projects in Tukwila, the greatest likelihood to
obtain funding would result from continued participation in the WRIA 9 forum and/or strategic
partnering with King County and state and federal agencies. Targeting funding requests to
address levee setback projects would fit well into the scientific and restoration plans/goals of the
organizations listed below. A few of these programs and organizations most relevant to Tukwila
are described below.
5.1.1 Puget Sound Action Team
The state legislature has appropriated a total of $182 million for state agencies and university
education programs for implementing the 2005-2007 Puget Sound Conservation and Recovery
Plan (PSAT, 2005). Funding is allocated by both priority area (e.g., habitat restoration (13
percent), stormwater (29 percent)) and state agency (e.g., Ecology, WDFW, WSU Extension,
etc.). The habitat restoration funds would be the best fit for opportunities in Tukwila.
5.1.2 Salmon Recovery Funding Board (SRFB)
With the listing of salmonid species under the Endangered Species Act in 1999, the Legislature
created the Salmon Recovery Funding Board. Composed of citizens appointed by the Governor
and five state agency directors, the Board provides grant funds to protect or restore salmon
habitat and assist related activities. It works closely with local watershed groups and has helped
finance over 500 projects. The Salmon Recovery Funding Board awarded $7.1 million during the
first five funding cycles for salmon habitat protection, restoration, and assessment projects in the
Green/Duwamish and Central Puget Sound Watershed (WRIA 9). These grants build on other
funding sources such as the King County Conservation District and Waterways 2000. The site-
specific opportunities in Tukwila (levee setbacks and off-channel habitat restoration on the
Green River) that have been identified in the WRIA 9 Salmon Habitat Plan are good candidates
and have the greatest likelihood of receiving SRFB funding.
5.1.3 King Conservation District
The King Conservation District (KCD) is a non-regulatory natural resources assistance agency
founded in 1949. The District promotes conservation through demonstration projects,
educational events, providing technical assistance, and, in some cases, providing or pointing the
way to funds that may be available for projects. The WRIA 9 Forum allocates approximately
$634,000 in King Conservation District funds annually to support habitat protection and
restoration projects, stewardship projects and programs, and essential technical assessments. As
of 2005, the highest priority for WRIA 9 KCD funding became projects and programs that are
informed by the strategies identified by the watershed Habitat Plan and the Strategic Assessment.
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5.1.4 Natural Resource Damage Assessment Funds
The history of industrial land use within the Green/Duwamish River valley has resulted in
discharge of pollutants to water and soils in the area. To remediate and mitigate for these
impacts, the United States brought litigation against the City of Seattle and King County. The
result of the settlement agreement resulted in the availability of National Resource Damage
Assessment (NRDA) funds for ecological restoration in the Duwamish. Several projects (e.g.,
Turning Basin 3, Herring’s House Habitat Restoration) have already been completed in this
vicinity. These funds are managed by NOAA, another partner in the Green/Duwamish River
Ecosystem Restoration Project.
5.1.5 King County Flood Control District
King County is in the process of developing a new Flood Control District to address flooding
issues throughout the county. Current plans call for spending $335 million to implement the
recommendations included in the recently adopted Flood Hazard Management Plan (King
County, 2006). These plans and projects include the installation of setback levees and inclusion
of habitat features as part of the overall flood control project. The plan was adopted by the King
County Council January 16, 2007 and on April 16, 2007 the Council adopted one flood control
district for the entire county.
5.2 Timelines and Benchmarks
In the context of the SMP update, restoration planning is a long-term effort. As stated earlier, the
SMP guidelines include the general goal that local master programs “include planning elements
that, when implemented, serve to improve the overall condition of habitat and resources within
the shoreline area” (WAC 173-26-201(c)). As a long-range policy plan, it is difficult to
establish meaningful timelines and measurable benchmarks in the SMP by which to evaluate the
effectiveness of restoration planning or actions. Nonetheless, the legislature has provided an
overall timeframe for future amendments to the SMP. In 2003, Substitute Senate Bill 6012
amended the Shoreline Management Act (RCW 90.58.080) to establish an amendment schedule
for all jurisdictions in the state. Once the City of Tukwila amends its SMP (on or before
December 1, 2009), the City is required to review, and amend if necessary, it’s SMP once every
seven years (RCW 90.58.080(4)). During this review period, the City could document progress
toward achieving shoreline restoration goals. The review could include:
• Re-evaluating adopted restoration goals, objectives, and policies;
• Summarizing both planning efforts (including application for and securing grant funds)
and on-the-ground actions undertaken in the interim to meet those goals; and
• Revising the SMP restoration planning element to reflect changes in priorities or
objectives.
Another mechanism that may serve to establish timelines and benchmarks would be
establishment of a shoreline restoration program organized like or integrated with the City’s
capital improvement program (CIP). Similar to an infrastructure CIP, a shoreline restoration CIP
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would be evaluated and updated regularly. The CIP would be focused on site-specific projects
and would be funded through grants. Further, other CIP projects, such as stormwater facility
improvements, could be evaluated to determine if their design could advance shoreline
restoration goals.
5.3 Mechanisms and Strategies for Effectiveness
The SMP guidelines for restoration planning state that local programs should “…appropriately
review the effectiveness of the projects and programs in meeting the overall restoration goals”
(WAC 173-26-201(2)(f)). Phase 3 of the restoration framework described previously (based on
Palmer et al, 2005) provides a general roadmap for assessing restoration actions and revising the
approach to meeting restoration goals. It includes the following objectives:
• Monitor post-restoration conditions;
• Adaptively manage restoration projects; and
• Use monitoring and maintenance results to inform future restoration activities.
These core objectives have been expanded upon by regional entities focused on restoration such
as the WRIA 9 Forum and the Puget Sound Nearshore Project (PNSP). Strategic principles and
concepts intended to guide ecosystem recovery are expressed in guidance publications (PSNP,
2004) and the WRIA 9 Salmon Habitat Plan (WRIA 9, 2006). The strategic principles and
concepts are very briefly summarized below:
• Purpose and Need. Potential restoration projects should be consistent with overarching
goals and objectives. For example, the WRIA 9 Salmon Habitat Plan establishes near-
term (the next 10 years) and long-term (50- to 100-year) goals to improve viable
salmonid population parameters, such as increased productivity (population
growth/abundance), improved genetic diversity, and improved distribution of habitat
throughout the watershed (spatial structure).
• Restoration Principles. Restoration planning should be strategic and restoration design
should be based on carefully developed goals and objectives. Follow-through, or
monitoring, should be employed, including development of performance criteria and use
of adaptive management in project development.
• Monitoring Principles. Three types of monitoring are defined: 1) implementation
monitoring to track which potential programs and projects are carried out; 2)
effectiveness monitoring to determine if habitat objectives of the program or project have
been achieved; and validation monitoring to confirm whether proposed restoration
actions are achieving the overall objectives for restoration. Monitoring should be driven
by specific questions, goals, and objectives and should be used as the basis for
determining if restoration goals are being met. Monitoring should be long-term and
interdisciplinary. Another component of monitoring is information management; data
should be well documented and available to others.
• Adaptive Management Principles. Adaptive management is a process that uses
research and monitoring to allow projects to proceed, despite inherent uncertainty and
risk regarding its consequences. Adaptive management is best accomplished at a
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regional or watershed scale, but can be used at a project level to increase knowledge
about ecosystems and how they respond to restoration actions.
6.0 CONCLUSIONS
State guidelines require all jurisdictions to address shoreline restoration planning as part of the
Shoreline Master Program update process (WAC 173-26-201(2)(f)). This restoration plan
presents an overall framework to allow the City of Tukwila to pursue the restoration of
ecosystem functioning within the Green/Duwamish River ecosystem. Key alterations to
ecosystem functioning were identified in previous inventory and characterization work:
1. The overall area over which key ecosystem functions occur is significantly reduced
from historic conditions. This area includes the important zone between fresh and salt
water that provides a transition for migrating fish.
2. Aquatic and wetland habitats are largely homogeneous in terms of both hydrology and
vegetative structure, and these habitats are typically restricted to the area within levees
and revetments within the City of Tukwila.
3. Degradation of water quality, especially water temperature, in the watershed above
Tukwila has effects that cannot be fully mitigated within the City.
4. Current levees would likely not meet current engineering standards.
Based on these alterations, we identified two key restoration actions for the aquatic ecosystems
within Tukwila:
1. Enlarging channel cross-sectional area. This action will increase flood storage, allow
for more stable levees and revetments, restore floodplain area, include the potential for
greater intertidal zone, and provide a smoother transition from aquatic to upland
habitats. This action could include the use of setback levees and revetments, and the
excavation of historic fill or floodplain materials to create back channels.
2. Enhance existing habitat characteristics. This action will improve the functioning of
the existing aquatic, riverine wetland, and riparian habitats that currently exist along the
Green/Duwamish River.
Based on the review of existing projects, it appears that these goals are at the core of most of the
projects being implemented via regional restoration efforts. The City of Tukwila is the lead on at
least one of these projects, and is pursuing additional projects. The City will maintain its active
role in regional restoration efforts, and continue to focus on improvement of functions in the
Green/Duwamish River ecosystem.
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7.0 REFERENCES
Anchor Environmental, LLC. 2004. Lower Green River Baseline Habitat Report. Prepared for
WRIA 9.
Brinson, M.M., 1993. A hydrogeomorphic classification for wetlands. Technical Report WRP-
DE-4, U.S. Army Waterways Experiment Station, Vicksburg, MS. NTIS No. AD
A270053.
E. S. Bernhardt, M. A. Palmer, J. D. Allan, G. Alexander, K. Barnas, S. Brooks, J. Carr, S.
Clayton, C. Dahm, J. Follstad-Shah, D. Galat, S. Gloss, P. Goodwin, D. Hart, B. Hassett,
R. Jenkinson, S. Katz, G. M. Kondolf, P. S. Lake, R. Lave, J. L. Meyer, T. K. O'Donnell,
L. Pagano, B. Powell, and E. Sudduth. 2005. Synthesizing U.S. River Restoration
Efforts. Science. 308(5722) 636-637.
ESA Adolfson. 2006. City of Tukwila Draft Shoreline Inventory and Characterization Report.
Prepared for the City of Tukwila. Seattle, Washington.
Green / Duwamish and Central Puget Sound Watershed Water Resource Inventory Area 9
Steering Committee (WRIA 9). August 2005. Salmon Habitat Plan – Making Our
Watershed Fit for a King. Prepared for the WRIA 9 Forum. Seattle, Washington.
King County. 2003. Lower Green River Corridor Assessment. Dated November 2003, King
County Department of Natural Resources and Parks. 24 pp.
King County. 2006. Draft Flood Hazard Management Plan: King County, Washington. King
County Department of Natural Resources and Parks, Water and Land Resources
Division, Seattle, Washington.
Kondolf, G.M. 1995. Five elements for effective evaluation of stream restoration. Restoration
Ecology 3(2):133-136.
Palmer, M.A., and J.D. Allan. 2006. Restoring Rivers; Policy Recommendations to Enhance
Effectiveness of River Restoration. Issues in Science and Technology, Winter 2006.
Accessable online at restoringrivers.org
Palmer, M.A., E.S. Bernhardt, J.D. Allan, P.S. Lake, G. Alexander, S. Brooks, J. Carr, S,
Clayton, C.N. Dahm, J. Follstad Shah, D.L. Galat, S.G. Loss, P. Goodwin, D.D. Hart, B.
Hassett, R. Jenkinson, G.M. Kondolf, R. Lave, J.L. Meyer, T.K. O’Donnell, L. Pagano,
and E. Sudduth. Standards for ecologically successful river restoration. Journal of
Applied Ecology. 42, 208-217.
Pentec Environmental. 2003. DRAFT Inventory of Shoreline Habitat and Riparian Conditions of
the Green/Duwamish River Within the City of Tukwila. Prepared for City of Tukwila.
January 7, 2003, Report: 12578-02.
Tukwila Shoreline Restoration Planning – SMA Grant No. 0600234
May 2007 26
Puget Sound Action Team (PSAT). 2005. 2005-2007 Puget Sound Conservation and Recovery
Plan. Olympia, Washington.
Puget Sound Nearshore Project (PNSP). 2004. Guiding Restoration Principles. Technical
Report 2004-03 available online: www.pugetsoundnearshore.org
Shared Strategy for Puget Sound (Shared Strategy). 2005. Draft Puget Sound Salmon Recovery
Plan. Submitted by Shared Strategy Development Committee. Seattle, Washington.
TerraLogic GIS, Inc and Landau Associates. 2004. Final: Lower Duwamish Inventory Report.
Technical report prepared for WRIA 9 Steering Committee. Seattle, WA.
United States Army Corps of Engineers (Corps Seattle District). 2004. Memorandum for
Record, Subject: Codiga Farms Baseline Monitoring Report. Reference: CENWS-PM-
PL-ER. July 23, 2004.
Washington Department of Ecology (Ecology). 2004. Restoration Planning and the 2003
Shoreline Management Guidelines. Ecology Publication No. 04-06-022. Olympia,
Washington.
Tukwila Shoreline Restoration Planning – SMA Grant No. 0600234
May 2007 27
8.0 ATTACHMENTS
Map 1. City of Tukwila Restoration Opportunity Sites: River Miles 4-7
Map 2. City of Tukwila Restoration Opportunity Sites: River Miles 7-11
Map 3. City of Tukwila Restoration Opportunity Sites: River Miles 11-15
Map 4. City of Tukwila Restoration Opportunity Sites: River Miles 15-17
Example Project Sheets
S
S
[
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[
[
[Per
i
met
er
Road1
1
5
7
9 108
6
4
C-3
3
C-1
C-2
2
River Mile 6
River Mile 5
River Mile 4
River Mile 7
11
S 112 St
S
R 9
9 East
Mar
gi
nal Way SS 102 St27 Ave SPer
i
met
er
RdS 94 Pl
S 87 Pl
S 86 Pl16 Ave SB o e i n g A c c e s s R d
P
eri
m
eter
R
d
Duwamish Riverbend
Hill Park
Cecil Moses
Park
S
S
[
S
!
!
[
[
[Per
i
met
er
Road1
1
5
7
9 108
6
4
C-3
3
C-1
C-2
2
River Mile 6
River Mile 5
River Mile 4
River Mile 7
11
S 112 St
S
R 9
9 East
Mar
gi
nal Way SS 102 St27 Ave SPer
i
met
er
RdS 94 Pl
S 87 Pl
S 86 Pl16 Ave SB o e i n g A c c e s s R d
P
eri
m
eter
R
d
Duwamish Riverbend
Hill Park
Cecil Moses
Park
City of Tukwila
Restoration Opportunity Sites:
River Miles 4 - 75/07
Legend
g
Scale: 1'=1200 feet
Shoreline Planning Area
Parks & Open Space
Tukwila City Limits
Potential Annexation Areas
Restoration Opportunity Areas
Complete
Restoration Sites:Status
Opportunity
Ongoing
1: Hamm Creek
Status: Opportunity
C-1: Kenco Marine/
Turning Basin #3 Project
Status: Complete
C-2: Coastal America
Turning Basin
Status: Complete
2: Area to south of
Coastal America
Turning Basin
Status: Opportunity
3: Duwamish Riverbank
Stabiliation atS 104th St
Status: Opportunity
4: North Wind Weir (Site #1)
Status: Ongoing
C-3: Cecil B. Moses Park
Status: Complete
5: Bank Restoration & Setback
Status: Opportunity
6: Riverton Creek
Status: Opportunity
7: Shallow Water Habitat Creation
Status: Opportunity
8: Duwamish Gardens
Status: Ongoing
9: S 115th Street
Status: Opportunity
10: Duwamish Riverbank
Stabilization
(near S 115th Street)
Status: Opportunity
S
![
P:\Jaimie\Restoration Maps
[S
[
[
[
§¨¦5
11
1 3
14
15
River Mile 9
River Mile 10
C-412River Mile 8River Mile 716
River Mile 11 17
11
14
12: Southgate Creek
Status: Opportunity
42 Ave SS 144 St
I
nt
er
ur
ban Ave SS 146 St
S 150 St 51 Ave St Macadam Rd S56 Ave S57 Ave S4
4 Pl
S
5
1
P
l
S
S 122 St
48 Ave S65S 152 St
M
artin L Kin
g Jr Wa
y S
S 137 St
S 129 St
S 143St
S 114 St
S 149 St
4
3
P
l
S
9
1
8
Foster Golf Course
Starfire at
Fort Dent Park
Foster Golf Course
Tukwila
Community
Center
Macadam
Wetlands
Park
Southgate Park
Codiga Farm
Park
Riverton
Park
Joseph
Foster
Memorial
Park
Park City of
Tukwila
Pool
Riverfront
Park
Hazelnut
Park
57th Ave. S.
Mini ParkRiverton
Mini
Park
[S
[
[
[
§¨¦5
11
1 3
14
15
River Mile 9
River Mile 10
C-412River Mile 8River Mile 716
River Mile 11 17
11
14
12: Southgate Creek
Status: Opportunity
42 Ave SS 144 St
I
nt
er
ur
ban Ave SS 146 St
S 150 St 51 Ave St Macadam Rd S56 Ave S57 Ave S4
4 Pl
S
5
1
P
l
S
S 122 St
48 Ave S65S 152 St
M
artin L Kin
g Jr Wa
y S
S 137 St
S 129 St
S 143St
S 114 St
S 149 St
4
3
P
l
S
9
1
8
Foster Golf Course
Starfire at
Fort Dent Park
Foster Golf Course
Tukwila
Community
Center
Macadam
Wetlands
Park
Southgate Park
Codiga Farm
Park
Riverton
Park
Joseph
Foster
Memorial
Park
Park City of
Tukwila
Pool
Riverfront
Park
Hazelnut
Park
57th Ave. S.
Mini ParkRiverton
Mini
Park
City of Tukwila
Restoration Opportunity Sites:
River Miles 7 - 115/07
Legend
g
Scale: 1'=1200 feet
Shoreline Planning Area
Parks & Open Space
Tukwila City Limits
Potential Annexation Areas
Restoration Opportunity Areas
Complete
Restoration Sites:Status
Opportunity
Ongoing
S
![
H:\GIS\Shoreline\Restoration map edits
Duwamish
Park
11: 42nd Ave S
Status: Opportunity
13: Bank Restoration &
Revetment Setback
Status: Opportunity
14: Shallow Water
Habitat Creation
Status: Opportunity
15: Create Off-Channel
Estuary Wetland
Status: Opportunity
16: Foster Golf Course
Riverbank Improvements
Status: Opportunity
17: Improve Confluence
of Black River &
Green River
Status: Opportunity
C-4: Codiga Farm
Status: Complete
18: Fort Dent Park
Status: Opportunity
[[
[
§¨¦405
19 20
21
River Mile 12
River Mile 13
River Mile 14
§¨¦5
River Mile 15In
t
er
ur
ban Ave SWest Valley HySouthcenter Blvd
Southcenter PkyAndover Park W51 Ave SAndover Park ES 180 St57 Ave STukwila Pky65 Ave SS 178 St
152 St
Industry DrMinkler Blvd
SW 43 St
t
Costco Dr
ark B DrMidland Dr
S 149 St
23
22
2 4
1
8
Starfire at
Fort Dent Park
Tukwila
Pond
Tukwila
Park
Park
Crystal
Springs
Park
Bicentennial
Park
Minkler Pond /
P-17 Pond Park
Hazelnut
Park
Ikawa
Park [[
[
§¨¦405
19 20
21
River Mile 12
River Mile 13
River Mile 14
§¨¦5
River Mile 15In
t
er
ur
ban Ave SWest Valley HySouthcenter Blvd
Southcenter PkyAndover Park W51 Ave SAndover Park ES 180 St57 Ave STukwila Pky65 Ave SS 178 St
152 St
Industry DrMinkler Blvd
SW 43 St
t
Costco Dr
ark B DrMidland Dr
S 149 St
23
22
2 4
1
8
Starfire at
Fort Dent Park
Tukwila
Pond
Tukwila
Park
Park
Crystal
Springs
Park
Bicentennial
Park
Minkler Pond /
P-17 Pond Park
Hazelnut
Park
Ikawa
Park
City of Tukwila
Restoration Opportunity Sites:
River Miles 11 - 155/07
Legend
g
Scale: 1'=1200 feet
Shoreline Planning Area
Parks & Open Space
Tukwila City Limits
Potential Annexation Areas
Restoration Opportunity Areas
Complete
Restoration Sites:Status
Opportunity
Ongoing
S
![
H:\GIS\Shoreline\Restoration map edits
18:Fort Dent Park
Status: Opportunity
19: Gilliam Creek
Status: Opportunity
20: Nelson Channel
Status: Opportunity
21: Side Channel Project
Status: Opportunity
22: Off-Channel &
Wetland Habitat
Creation
Status: Opportunity
23: Acquisition,
Levee Setback &
Habitat Rehabilitation
Status: Opportunity
24: Desimone
Levee Projects
Status: Opportunity
S
Frager RdS 194th St
S 190th St
S 196th St
S 200th StOrillia Rd SS 188th St
River Mile 15
River Mile 16
River Mile 17
24: Desimone
Levee Projects
Status: Opportunity
C-5: Desimone Levee
(portion that has
already been fixed)
Status: Complete
S 180 St
178 St
SW 43
Riverside Dr
C-5
2 6
25
2 4
Briscoe
Meander
Park
S
Frager RdS 194th St
S 190th St
S 196th St
S 200th StOrillia Rd SS 188th St
River Mile 15
River Mile 16
River Mile 17
24: Desimone
Levee Projects
Status: Opportunity
C-5: Desimone Levee
(portion that has
already been fixed)
Status: Complete
S 180 St
178 St
SW 43
Riverside Dr
C-5
2 6
25
2 4
Briscoe
Meander
Park
City of Tukwila
Restoration Opportunity Sites:
River Miles 15 - 175/07
Legend
g
Scale: 1'=1200 feet
Shoreline Planning Area
Parks & Open Space
Tukwila City Limits
Potential Annexation Areas
Restoration Opportunity Areas
Complete
Restoration Sites:Status
Opportunity
Ongoing
S
![
H:\GIS\Shoreline\Restoration map edits
Duwamish
Park
25: Segale Levee Projects
Status: Opportunity
26: Johnson Creek
Status: Opportunity
North Wind Weir
Site
•Salmon Plan Site DUW 10
•Part of Ecosystem Restoration
Project
•Potential for ~2 acres of
back/side intertidal channel
habitat
Project Purpose
•Acquire available undeveloped
property along the Duwamish Estuary
•Increase channel area
•Enhance habitat characteristics in the important transition zone between fresh and
salt water
•High Priority Restoration Action.
Completed project on the left bank
Current Status
•Property acquired in 2001
•Joint project between Tukwila, USACOE, and King County (lead)
•Funding provided by SRFB, Elliot Bay/Duwamish Restoration program, Washington
State, King County, Seattle, and Tukwila.
•Construction anticipated to be completed in 2007
Riverton Creek
Site
•Salmon Plan Site DUW 8
•Part of Ecosystem
Restoration Project
•Potential for ~3.4 acres
intertidal channel habitat
on freshwater input point.
Project Purpose
•Replace flap gate with self-regulating tide gate
•Increase intertidal area area
•Enhance habitat characteristics in the important transition zone between fresh and
salt water
Current Status
•Funding source not identified
•Site is in public ownership
•Opportunity to team with WSDOT.
Duwamish
Gardens Site
•Salmon Plan Site DUW 7
•Part of Ecosystem
Restoration Project
•Potential for ~2.1 acres
of intertidal channel
habitat.
Project Purpose
•Increase intertidal area area
•Enhance habitat characteristics in the important transition zone between fresh and
salt water
Current Status
•SRFB funding obtained for property acquisition
•CIP# 98-DR06
•Coordination with WSDOT underway.
Gilliam Creek Site
•Salmon Plan Site LG-16
•Part of Ecosystem Restoration Project
•City CIP 98-DR05
•Potential for ~2,000 linear feet of channel
restoration.
Project Purpose
•Remove existing fish passage barrier
•Install fish ladder
•Enhance in-stream habitat characteristics with large wood and riparian vegetation.
Current Status
•Funding not yet identified
•Coordination with WSDOT underway.
Nelson Side Channel Site
•Salmon Plan Project LG-15
•City CIP 03-PK04
•Potential for ~2 acres of channel
rehabilitation.
Project Purpose
•Connect remnant river channel to the river to create off-channel refugia for
juvenile fish.
•Restore river bank by sloping river side channel and adjacent levee.
•Install riparian vegetation.
Current Status
•Conceptual planning stage.
•Funding not yet identified.