HomeMy WebLinkAboutPANTHER CREEK WATERSHED REHABILITATION PLAN I
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1 PRELIMINARY DRAFT FOR MULTI-AGENCY PERMITTING
2 TEAM (MAPT) REVIEW
3 1-405 Water Resource Initiative at the Panther Creek Wetlands
4 1-405, 1-5 to SR 169 Master Plan
5 PANTHER CREEK WATERI iHf.D REHABILITATION PLAN
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MWashington State May 2007
Department of Transportation . y
�- r
COwoRECEIVED
DAVID EVANS JUN 2 0 2`007
ANoASSOCIATES INC.
pyTOpFQCAITG 1
TRANSMITTAL UTILITY SYSTEMS
DATE: June 18, 2007 PAGES: 1
TO: Ronald J. Straka,P.E. TELEPHONE NO: 1-425-430-7248
City of Renton FAX NO:
Surface Water Utility Engineering
Supervisor
1055 S. Grady Way-5th Floor
Renton WA 98055
FROM: Dale Anderson TELEPHONE NO: 425.519.6500
FAX NO: 425.519.5361
PROJECT: Panther Creek Watershed Rehabilitation Plan (PCWRP)
PROJECT NO: WDOT 0000 0354
❑ AS YOU REQUESTED ❑ FOR YOUR APPROVAL ❑ RETURN REQUESTED
® FOR YOUR INFORMATION ❑ RECORDS MANAGEMENT ® FOR YOUR USE
El
ITEM COPIES DATE DESCRIPTION
1 4 MAY 2007 Preliminary Draft-Panther Creek Watershed
Rehabilitation Plan -May 2007
1 4 5/30/2007 Transmittal Letter to MAPT-Co-Endorsement
Letter
COMMENTS:
Hi Ron—As noted on the report cover,this is the latest version of the PCWRP that was provided to the Multi-
Agency Permitting Team(MAPT) at the June 4`h briefing. We have started receiving agency comments and we
requested MAPT comments by June 22"a as noted in the co-endorsement letter. I'll keep you posted on results.
As you'll see, we added the Springbrook Trail and deleted the preservation language in this version of the
PCWRP. Let me know if you have questions. Regards, Dale
415 118th Avenue SE Bellevue Washington 98005-3518 Phone:425.519.6500 Facsimile:425.519.5361
AZonald J. Straka,P.E.
June 18, 2007
Page 2
Copies: I-405 Team Files
Attachments/Enclosures: PCWRP and Co-Endorsement Letter
Initials: dxan
File Name: P:W\WSOT00000354\300Com\31 lAgency
Project Number: WDOT 0354
I iCorridor Pr• •
Conqestion Relief& Bus Rapid Transit 600-108th Avenue NE,Suite 405
Bellevue,WA 98004
May 30, 2007 Main 425-456-8500
Fax 425-456-8600
Terry Drochak MS:NB82-250
Manager- Multi-Agency Permitting Team
Ecology NWRO
Attn: MAP Team
MS: NB-81
3190 160th Avenue SE
Bellevue, WA, 98008
Re: WSDOT and City of Renton Co-Endorsement of the Panther Creek Watershed
Restoration Plan (PCWRP) Concept
Dear�Mr. Drochak:
WSDOT, in partnership with the City of Renton, is pleased to submit the Panther Creek
Watershed Restoration Concept for the MAPT staff consideration.
WSDOT and the City administration agree that there are mutual environmental benefits
from the implementation of the concept described in the Panther Creek Watershed
Restoration Plan:
• Provides habitat benefits to Panther Creek and the Panther Creek Wetland
o Establishes off-channel fish refuge and rearing habitat in Panther Creek
Wetland
o Promotes water aeration by providing a new stream channel
o Provides riparian plantings to shade and reduce water temperatures
o Removes three fish passage barriers in Panther Creek
o Provides enhanced water quality treatment of highway drainage
o Enhances 33 acres of floodplain habitat
• Builds upon the City's Eastside Green River Watershed Plan
• Implements Springbrook Creek improvements within the City of Renton,
which provides progress towards implementation of the Regional Salmon
Habitat Plan and the Army Corp's Green River Ecosystem Restoration Project
• Improves surface water management and reduces flooding along East Valley
Road and the SW 34th Street drainage system
• Provides a unique opportunity for PCWRP implementation due to the I-405
Project's staged highway improvements
.ice
Washington State
,r Department of Transportation
Terry Drochak
May 30, 2007
Page 2
The City and WSDOT's co-endorsement of the PCWRP signifies our support for the
Conceptual Plan. We request the MAPT review and provide comments on the Plan. We
are interested in obtaining MAPT feedback on the plan from a permitting perspective;
particularly any potential problems you think we may encounter. We would also
appreciate any insight MAPT has on the overall concept of providing a watershed-level
stream mitigation plan for the I-405 Master Plan. WSDOT also plans to present the
PCWRP to the Muckleshoot Tribe Fisheries Division, after the MAPT has reviewed the
Concept, for their review and comment. WSDOT needs to determine if the PCWRP will
be accepted as a watershed—level plan to guide a portion of the stream mitigation and
stormwater management for the I-5 to SR 169,Tukwila to Renton Improvement Project.
The I-405 team will publish a NEPA Environmental Assessment for the Tukwila to
Renton Improvement Project in the fall of 2007. We would appreciate your comments by
June 22, 2007.
We appreciate the MAPT member's time and consideration of the PCWRP Concept.
Si e y,
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a ordan
I-405 rrect Environmental Manager
wil iordan@i405.wsdot.wa.gov
cc: Ron Straka, City of Renton; Dale Anderson, I-405 Water Resources Coordinator
25 PRELIMINARY DRAFT FOR MULTI-AGENCY PERMITTING
26 TEAM (MAPT) REVIEW
27 1-405 Water Resource Initiative at the Panther Creek Wetlands
28 1-405, 1-5 to SR 169 Master Plan
29 PANTHER CREEK WATERSHED REHABILITATION PLAN
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35 Prepared for
36 WSDOT
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41 Prepared by
42 1-405 Team
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46 May 2007
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49 WSDOT Acknowledgements
50 The following team members contributed to this work:
51 Allison Ray—1-405 Environmental Management Oversight
52 Alan Black—1-405 Drainage Engineering Oversight
53 Dale Anderson—Project Manager
54 Jon Gage—Assistant Project Manager and Primary Author-Concept Plan & Habitat Improvements
55 Barb Kittel—Senior Editor
56 Greg Konkel—GIS Analyst
57 Technical Assistance provided by:
58 Anthony Stirbys—Geotechnical Investigations
59 Derek Koellmann, Paul LaRiviere, Matthew Gray, Jack Bjork—Fish Passage&Fisheries
60 Larry Karpack, Andre Ball—Hydrologic Modeling/Water Surface Elevations
61 Mark Matthies&Torrey Luiting—Wetlands
62 Ralph Nelson &Michael Gisebert—Hydrology/Hydraulics Review
63 Terry Drochak-Permitting
64 Appreciation is expressed to the following City of Renton Staff for their participation:
65 Ron Straka
66 Allen Quynn
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TABLE;OF CONTENTS
69 TABLE OF CONTENTS
70 Glossary............................................................................................................................................................iii
71 Acronyms.........................................................................................................................................................vii
72 Introduction .......................................................................................................................................................1
73 What is the 1-405, 1-5 to SR 169 Master Plan? ...............................................................................................1
74 What is an 1-405 Water Resource Initiative?...................................................................................................1
75 What is this specific Water Resource Initiative for the 1-405, 1-5 to SR 169 Master Plan?.............................2
76 What are the key points of this Concept Plan?...............................................................................................4
77 Purpose.......................................................................................................................................................4
78 Benefits and Costs of Plan Implementation................................................................................................4
79 What are the implementation/permitting considerations?...............................................................................6
80 Schedule considerations.............................................................................................................................7
81 Existing Conditions ..........................................................................................................................................9
82 What watershed is being studied?..................................................................................................................9
83 What are the limiting factors in the watershed?..............................................................................................9
84 What is the current status of wetlands?........................................................................................................11
85 Panther Creek Wetlands west of SR 167.................................................................................................12
86 Panther Creek Wetlands east of SR 167..................................................................................................12
87 What are the constraints to stream rehabilitation within the Panther Creek Wetlands?...............................17
88 What is the current status of the streams &fish habitat in the watershed areas proposed by this concept
89 plan?..............................................................................................................................................................18
90 Springbrook Creek....................................................................................................................................18
91 Panther Creek...........................................................................................................................................20
92 East Fork— Downstream of SR 167 .........................................................................................................20
93 East Fork- upstream of SR 167 (South Wetland)....................................................................................22
94 West Fork—downstream of SR 167.........................................................................................................23
95 Rolling Hills Creek.....................................................................................................................................24
96 Thunder Hills Creek..................................................................................................................................25
97 What is the current status of water quality in Panther and Springbrook Creeks? ........................................27
98 What is the current status of stream flow diversions in the watershed?.......................................................28
99 What is the current status of wildlife in the watershed areas proposed by this concept plan?.....................28
100 Concept Development....................................................................................................................................31
101 What are the 1-405 improvements that this concept plan addresses?..........................................................31
102 What are the stream and wetland effects? ...................................................................................................32
103 What objectives are proposed to rehabilitate streams and fish habitat? ......................................................33
104 Stream Rehabilitation 1 (SR1) ..................................................................................................................34
105 Stream Rehabilitation 2 (SR2) ..................................................................................................................40
106 Stream Rehabilitation 3 (SR3) ..........................................................................:.......................................40
107 Stream Rehabilitation 4 (SR4) ..................................................................................................................42
108 Stream Rehabilitation 5 (SR5) ..................................................................................................................42
109 Stream rehabilitation summary.................................................................................................................43
110 What objectives are proposed for associated floodplain improvements?.....................................................44
111 North Wetland ...........................................................................................................................................44
112 South Wetland...........................................................................................................................................44
113 Floodplain Improvements summary..........................................................................................................46
114 What objectives are proposed for surface water?.........................................................................................47
115 How does this plan fit into the context of other watershed projects?............................................................52
116 What are the benefits and costs of implementing this concept?...................................................................53
117 What is the permitting strategy for this plan?................................................................................................54
118 What are the next steps to move forward? ...................................................................................................56
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TABLE OF CONTENTS
119 References.......................................................................................................................................................57
120 Published Documents ...................................................................................................................................57
121 Personal Communications............................................................................................................................59
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124 Appendices
125 A. Preliminary Geotechnical Investigation
126 B. Fish Habitat Memoranda
127 C. Green-Duwamish G.I. Ecosystem Restoration Feasibility Study— Project Description for Lower
128 Springbrook Reach
129 D. Hydraulic and Hydrologic Analyses Memoranda
130 E. Planning-Level Cost Estimate
131 F. Memorandum on Wetlands
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133 EXHIBITS
134 Exhibit 1. Project Vicinity Map.........................................................................................................................3
135 Exhibit 2. Benefits of the PCWRP as related to salmonid limiting factors in Panther Creek/Springbrook Creek
136 .................................................................................................................................................................5
137 Exhibit 3. Panther Creek Wetlands Existing Conditions and Planned City Trails (City of Renton, 1990 and
138 1992)......................................................................................................................................................13
139 Exhibit 4. Stream Reaches Evaluated for this Project..................................................................................19
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140 Exhibit 5. Stream Habitat Conditions Summary............................................................................................26
141 Exhibit 6. 2001 and 2002 Springbrook Creek and Panther Creek median base flow water quality values .27
142 Exhibit 7. Potential Stream Effects From Master Plan Footprint...................................................................32
143 Exhibit 8. Potential Wetland Effects From Master Plan Footprint.................................................................33
144 Exhibit 9. Concept Plan.................................................................................................................................35
145 Exhibit 10. Concept Plan Enlargement.........................................................................................................37
146 Exhibit 11. Summary of Proposed Stream Rehabilitation.............................................................................43
147 Exhibit 12. Typical Panther Creek Wetland Cross Section A-A....................................................................45
148 Exhibit 13. Summary of Associated Floodplain Improvements.....................................................................46
149 Exhibit 14. Predicted Average Monthly Panther Creek Stream Flows Entering the South Panther Creek
150 Wetland for Current Conditions Compared to the Recommended Flow Management Strategy...........48
151 Exhibit 15. Predicted Surface Water Elevations in the Panther Creek Wetland for Different Flood Flows for
152 Baseline (Existing) Conditions versus the Recommended Flow Management Strategy.......................49
153 Exhibit 16. Benefits of the PCWRP as related to salmonid limiting factors in Panther Creek/Springbrook
154 Creek .....................................................................................................................................................54
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Gl.,osSARY
156 GLOSSARY
100-year flood event A flood having a 1-percent chance of occurring in any given year.
alluvial fan An area of major sediment deposition,formed where a stream rapidly loses its transporting ability
because of either an abrupt reduction in slope or a sudden change from a confined to unconfined
channel, leading to flow divergence.
anadromous fish A fish species that spends a part of its life cycle in the sea and returns to freshwater streams to
spawn(reproduce). Examples of anadromous species include salmon and steelhead trout.
bankfull width The width of the stream channel between the top of the streambanks where, under high flow
conditions,the water level would be even with the top of the banks,or in a floodplain river,at the
pointjust before water would spill over onto the floodplain,
base flood A flood having a 1-percent chance of occurring in any given year;also called the 100-year flood.
base flow Base flow refers to the volume of flow in a stream or river during dry conditions,as opposed to
conditions influenced by storm runoff. The portion of a stream's flow that comes from the
groundwater.
best management practice Best management practices,referred to commonly as BMPs,are methods used to minimize or
avoid effects to water quality such as sediment getting into streams during construction.
Examples of BMPs include installing filter fabric fence downstream of all exposed slopes,around
existing drainage inlets,and along river,stream,and drainage channels near work areas to
prevent sediment-laden stormwater from entering streams.
box culvert A concrete box structure that drains open channels,swales,or ditches under a roadway or
embankment.
buffer A designated area along and adjacent to a stream or wetland that may be regulated to control
the negative effects of adjacent development on the aquatic resource.
compensatory floodplain The removal of material from a site in the same floodplain and at the same elevation to
storage compensate for the placement of any fill within the limits of the regulatory floodplain.
construction footprint The physical area impacted by project construction activities.
critical areas Critical areas include both hazard areas(such as floodplains and steep slopes)and
environmentally sensitive areas(like wetlands and streams). Critical areas also include areas
that are important for protecting groundwater. The state Growth Management Act requires
counties to protect the"functions and values"of critical areas. Examples of wetland functions
are filtering out pollutants,providing wildlife habitat,controlling floods,and recharging
groundwater.
critical habitat Under the Endangered Species Act,(1)the specific areas within the geographic area occupied
by a federally listed species on which are found physical and biological features essential to the
conservation of the species,and that may require special management considerations or
protection;and(2)specific areas outside the geographic area occupied by a listed species when
it is determined that such areas are essential for the conservation of the species.
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GLOSSARY
culvert A concrete structure that drains open channels, swales,or ditches under a roadway or
embankment.
ecosystem Community of organisms interacting with each other,and the environment in which they live.
emergent wetlands Wetlands comprised of plants that are rooted below the water but have foliage that extends out
of the water.
erosion The wearing away of soil or rock by the action of running water,wind, ice,or geologic agents.
For this report,erosion relates primarily to stormwater runoff.
fill Fill refers to materials placed to construct structures within waters of the United States, including
streams and wetlands. Fill materials can be rock, sand,or dirt.
floodplain The total area subject to inundation by a flood, including the floodway.
flow rate The volume of water that moves past a particular point in one second. The flow rate is measured
in cubic feet per second.
fluvial geomorphology Refers to"Geomorphology'which is the science of the shape of the earth's surface,the
processes that mold this surface,and consequently, how the surface will change its shape over
time. More specifically,"fluvial geomorphology'is the study of landform evolution related to
stream systems. As an integrative field it includes the related disciplines of geology, hydrology
and hydraulics,sediment transport,soil mechanics, and the mechanical effects of vegetation.
hydroperiod The period of time that a wetland is covered by water.
hydric soil Soils that develop anaerobic(absence of oxygen)conditions under persistently wet conditions.
hydrology The science dealing with the properties,distribution,and circulation of water.
hydrophytic vegetation Vegetation that is able to grow and thrive under wet soil conditions.
impervious surface Surfaces through which water cannot percolate such as pavement, roofs,and compacted or
hardened surfaces.
large woody debris Coniferous or deciduous logs, limbs,or root wads 12 inches or larger in diameter and a length of
at least 6.5 feet that intrude into or bridge above a stream channel.
nutrient Essential chemicals needed by plants and animals for growth,such as phosphorus.
ordinary high water mark The line on the shore established by the change in water levels and indicated by physical
characteristics such as a clear, natural line impressed on the bank or the presence of litter and
debris. The presence and action of water generally leaves an impression on the stream bed and
banks that makes a distinct separation between the stream and the adjacent areas and indicates
the location of the ordinary high water mark.
palustrine In the USFWS classification system,freshwater areas(having less than 0.5 parts per thousand
ocean-derived salts)dominated by trees,shrubs,persistent emergents, mosses,or lichens.
These areas can be tidal(waters which alternate by rising and falling)or non-tidal. Palustrine
also includes wetlands lacking this vegetation but having the following characteristics: (1)area
less than 20 acres;(2)no active wave-formed or bedrock shoreline; (3)deepest water depth is
less than 6.6 feet at low water.
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GLOSSARY
palustrine emergent(PEM) In the USFWS classification system,a wetland characterized by erect,rooted, non-woody plants
such as cattails, rushes,and sedges.
palustrine forested(PFO) In the USFWS classification system,a wetland characterized by woody vegetation that is 20 feet
tall or taller.
palustrine scrub-shrub(PSS) In the USFWS classification system, areas dominated by woody vegetation less than 20 feet tall,
such as trees, shrubs or young trees that are stunted due to environmental conditions.
peak flow Peak flow refers to a specific period of time when the discharge of a stream or river is at its
highest point.The maximum instantaneous rate of flow during any given storm. For this report,
peak flow refers to the 100-year storm event.
refuge habitat An area of a stream that provides shelter or safety for aquatic species,
riparian corridor The land and the vegetation community directly adjacent to(or surrounding)a natural or artificial
waterway including streams, rivers,wetlands and lakes.
riparian habitat The aquatic and terrestrial habitat adjacent to streams, lakes,estuaries,or other waterways.
Riparian habitat areas are also commonly referred to as riparian buffers.
salmonid Any member of the family Salmonidae,which includes all species of salmon,trout,and char
(including bull trout).
scrub-shrub wetlands Wetlands dominated by woody vegetation less than 20 feet tall. Vegetation in scrub-shrub
wetlands includes tree shrubs,young trees,and trees or shrubs that may be stunted because of
environmental conditions. Scrub-shrub wetlands are flooded for extended periods during the
growing season.
sediment Material that originates from weathering and erosion of rocks,dirt,or unconsolidated deposits
and organic material. Sediment travels through the movement of water,particularly stormwater
runoff and is usually suspended within the water.
sedimentation Particles deposited or settling out of the water column and forming sediment on the bed of a
channel or water course,
side channel This is a secondary stream that splits off the main channel.
stormwater The portion of precipitation that does not naturally percolate into the ground or evaporate,but
flows overland, in channels,or in pipes into a defined surface water channel or a constructed
stormwater facility.
stormwater detention Storing stormwater in manmade facilities such as ponds and releasing the stormwater at a
controlled rate. This process helps control how much and how fast stormwater enters streams
and rivers. Controlling the flow of stormwater helps maintain existing base flood levels and
minimizes erosion of stream banks.
substrate Organic and mineral materials that form the bed of a body of water.
tributary A stream or other body of water that contributes its water to another stream or body of water.
turgidity A condition caused by suspended sediments or floating material that clouds the water and
makes it appear dark and muddy.
1-405 Water Resource Initiative at Panther Creek Wetlands
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PRELIIIIINARY DRAFT FOR MIILTI-AGENCY PERiMITTEVG TEAM(MLkPT)REVIEW
GLOSSARY
wetland Wetlands are formally defined by the U.S.Army Corps of Engineers, the U.S. Environmental
Protection Agency,the Washington Shoreline Management Act of 1971 (SMA),and the Growth
Management Act(GMA) as:
"... those areas that are inundated or saturated by surface or groundwater at a frequency and
duration sufficient to support,and that under normal circumstances do support,a prevalence of
vegetation typically adapted for life in saturated soil conditions. Wetlands generally include
swamps, marshes,bogs,and similar areas."
The SMA and the GMA definitions add:
"Wetlands do not include those artificial wetlands intentionally created from non-wetland sites,
including,but not limited to, irrigation and drainage ditches,grass-lined swales, canals, detention
facilities,wastewater treatment facilities,farm ponds,and landscape amenities,or those
wetlands created after July 1, 1990 that were unintentionally created as a result of the
construction of a road,street,or highway. Wetlands may include those artificially-created
wetlands intentionally created from non-wetland areas to mitigate the conversion of wetlands."
wetland boundary The point on the ground at which a shift from wetlands to nonwetlands or aquatic habitat occurs.
These boundaries usually follow topographic contours.
wetland hydrology The presence of water during a portion(between 5 and 12.5 percent)of the annual growing
season.
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ACRONYMS
158 ACRONYMS
BMP best management practice
BNSF Burlington Northern Santa Fe
BRPS Black River Pump Station
cfs cubic feet per second
Corps U.S.Army Corps of Engineers
DNR Washington State Department of Natural Resources
DO dissolved oxygen
EA Environmental Assessment
Ecology Washington State Department of Transportation
ESA Endangered Species Act
ESGRWP East Side Green River Watershed Project
FAA Federal Aviation Administration
GMA Growth Management Act
GP general-purpose
HOV high occupancy vehicle
HRM Highway Runoff Manual
I Interstate
KCDD1 King County Drainage District 1
KCDNR King County Department of Natural Resources
LF linear feet
LWD large woody debris
NB Northbound
nhc northwest hydraulic consultants
NMFS National Marine Fisheries Service
OHWM ordinary high water mark
PCW Panther Creek wetlands
PCWRP Panther Creek Watershed Rehabilitation Plan
PEM palustrine emergent
PFO palustrine forested
PSS palustrine scrub-shrub
ROW right-of-way
RTID Regional Transportation Improvement District
SB Southbound
SMA Shoreline Management Act
SR State Route
TSS total suspended solids
USFWS U.S. Fish and Wildlife Service
WDFW Washington State Department of Fish and Wildlife
WRIA Water Resource Inventory Area
WSDOT Washington State Department of Transportation
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ACRONYMS
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I-405 Water Resource Initiative at Panther Creek Wetlands
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IN-rRODI.TCTION
161 INTRODUCTION
162 What is the I-405, I-5 to SR 169 Master Plan?
163 The 1-405, 1-5 to SR 169 Master Plan (referred to as
164 Master Plan herein) is part of the long-term corridor
165 transportation plan for Interstate 405 (1-405). The
166 Master Plan addresses the need to improve personal
167 and freight mobility and reduce foreseeable traffic
168 congestion in the corridor, providing a transportation
169 system that is safe, reliable, and cost-effective.
170 The Master Plan is likely to be constructed in stages
171 as funding becomes available. Each stage includes
172 highway improvements that affect streams and
173 wetlands and increase the amount of impervious
174 highway surface within the existing watershed
175 landscape.
176 What is an I-405 Water Resource Initiative?
177 An 1-405 Water Resource Initiative looks beyond
178 conventional approaches to stream mitigation and
179 stormwater management.
180 In regards to stream mitigation, conventional
181 approaches typically provide mitigation in the
182 What is a watershed? immediate area of the effects and may not consider
183 A watershed is the region of land that drains the downstream or watershed context of the
184 into a specified body of water, such as a river, mitigation. Mitigation in the immediate vicinity of the
185 lake, sea, or ocean. Rain that falls anywhere effects may result in habitat improvements that have
186 within a given body of water's watershed will little, if any connectivity to downstream or upstream
eventually drain into that body of water.
187 habitat in urbanized watersheds.
188 In regards to stormwater management, the
189 Washington State Department of Transportation
190 (WSDOT) has published a Highway Runoff Manual
191 (HRM) that presents stormwater management
192 approaches. The HRM includes "conventional"
193 approaches that typically use large concrete vaults or
194 roadside ponds and swales to provide stormwater
195 detention and treatment within the highway right-of-
196 way (ROW. The conventional approach for highway
197 stormwater management represents a significant cost;
198 the cost is estimated to be in excess of$1 billion for
199 the 1-405 Corridor.
200 The 1-405 Water Resource Initiative focuses on stream
201 mitigation and stormwater management and provides
202 for:
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INTRODUCTION
203 1. Potential efficiencies/economies of scale by
204 combining with local agency projects and/or local
205 jurisdictions;
206 2. Environmental improvements outside of the
207 immediate highway ROW;
208 3. Possibilities to integrate contributions to other
209 social goals without compromising efficiency in
210 meeting transportation goals; and
211 4. The greatest environmental benefit while spending
212 the least amount of transportation funding.
213 What is this specific Water Resource Initiative for the I-405, I-5 to
214 SR 169 Master Plan?
215 The intent of the Panther Creek Watershed
216 Rehabilitation Plan (PCWRP) is to take a look at the
217 combined effects on streams and wetlands of all 1-405
218 Master Plan improvements and conduct a watershed
219 level assessment to determine appropriate stream
220 mitigation actions that can provide the most benefit to
221 the overall watershed.
222 WSDOT intends to provide wetland mitigation in this
223 portion of the 1-405 Corridor by debiting credits from
224 the Springbrook Creek Wetland and Habitat Mitigation
225 Bank.
226 This PCWRP water resource initiative provides a
227 watershed stream mitigation plan for the Master Plan
228 that can be staged to match the impacts of the staged
229 highway projects. The stream mitigation is intended to
230 mitigate impacts in the Panther Creek and lower
231 Springbrook Creek sub basins.
232 Highway drainage is an important factor affecting
233 streams in the 1-405 Corridor. This plan also
234 evaluates highway drainage and how it could be cost-
235 effectively managed to compliment the stream
236 mitigation work. Exhibit 1 shows the watershed
237 rehabilitation plan locations.
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INTRODUCTION
I-405 •
A Northern
' Project Limit ,
at SR 169
i ' P.1 Y C.d 41 1
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7 t�°" 169
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SR 167 `
r, Southern 515
I Project Limit
at SW 41st St
167
Arterial Road Master Plan
( � Project Limit
Freeway Panther Creek
Stream or Drainage S Watershed Rehabilitation
Lake Project Areas er
Wetland 5pringbrook Creek
5ubbasin
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[1 r' Municipality Panther Creek 0 025 0.5
238 5ubbasin _ `
239 Exhibit 1. Project Vicinity Map
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Panther Creek Watershed Rehabilitation Conceptual Plan 3
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240 What are the key points of this Concept Plan?
241 Purpose
242 The purpose of this concept plan is to identify a
243 watershed-level mitigation plan that can be
244 implemented in tandem with highway construction
245 stages by WSDOT and/or the City of Renton.
246 The Concept Plan serves as a communication tool to
247 gain support from and involve the City of Renton,
248 resource agencies, tribes, and citizens.
249 The plan identifies goals, objectives, benefits, and
250 planning-level costs. The concept plan evaluates
251 feasibility and defines design needs and challenges.
252 This document will provide a basis of design for
253 individual mitigation projects.
254 Benefits and Costs of Plan Implementation
255 The benefits of implementing this conceptual plan are
256 to provide:
257 • Stream mitigation for the 1-405, 1-5 to SR 169
258 Master Plan that addresses limiting factors at a
259 "watershed level."
260 . Fish habitat improvements via stream flow
261 management to: (1) provide more reliable
262 stream base flows, (2) create stream flow
263 changes that are compatible with wetland
264 floodplain enhancement, and (3) manage
265 stream flows to be compatible with
266 downstream flood control needs.
267 A direct discharge of treated highway
268 stormwater into the Panther Creek wetland
269 complex to provide additional project benefits.
270 A key benefit is to address the City of Renton
271 Airport Operator's air traffic safety concern for
272 building new open-water detention facilities
273 within the 1-405/SR 167 Interchange. These
274 facilities would be within a restricted area for
275 aircraft flight paths. Air traffic safety is a key
276 concern due to high costs and fatality issues
277 associated with bird strikes. The direct
278 discharge approach is also compatible with the
279 habitat mitigation proposal and more cost-
280 effective than conventional stormwater
281 management.
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282 As part of the watershed-level assessment, we
283 defined key factors that limit the production of fish,
284 specifically salmonids. Implementation of the PCWRP
285 will provide stream habitat improvements that address
286 limiting factors for salmonid production in Panther
287 Creek and a portion of Springbrook Creek. Exhibit 2
288 provides a summary of how the PCWRP addresses
289 limiting factors for salmonid production.
290
Exhibit 2. Benefits of the PCWRP as related to salmonid limiting factors in Panther
Creek/Springbrook Creek
salmonid Limiting Factors
DegradedLack of Salmonid Quality Lack of Functioning Riparian
Refuge Habitat
Establishes 0.50 Cascades to be provided in 7,750 linear feet(162,000 Removes 3
Benefits of the acre of off-channel new channel design(at square feet)of in-channel barriers(620 LF)
Panther Creek rearing habitat in alluvial fan)to provide water improvements,including 5,350 to fish passage
Watershed Panther Creek aeration and improve linear feet in Panther Creek within Panther
Rehabilitation Plan wetland dissolved oxygen and 2,400 linear feet in Creek and
concentrations in Panther Springbrook Creek connects up to 3
and Springbrook Creeks. miles of Panther
36.9 acres of associated Creek riparian
Riparian shade tree plantings floodplain improvements to habitat for fish use
to lower summer water stream buffer/wetlands
temperatures including 12.8 acres of stream
buffer restoration to left bank of
east fork Panther Creek to
provide required buffer width
Enhanced water quality
treatment of WSDOT
stormwater discharged to the
Panther Creek wetland
complex
291
292 How do project costs break out?
293 Stream Rehabilitation $5,075,000 The planning level cost to implement the watershed-
294 Floodplain Improvements $2,413,000 level stream mitigation plan is approximately $13.9
295 Fish Passage Improvements $2,115,000 million (See Break Out).
296 Springbrook Trail $906,000 The planning level cost (today's dollar) for highway
297 Subtotal $10,509,000 improvements in this area is $1.03 billion. The
298 Sales Tax (8.80%) $925,000 stormwater management (quantity and quality) portion
299 Contingency(10%) $1,051,000 of these highway costs, using conventional practices,
300 PSE &Permitting (11%) $1,373,000 is $46 million. The stormwater management cost
301 providing a direct discharge of treated stormwater, as
302 Grand Total $13,858,000 recommended in this PCWRP, is $29 million.
303 Costs are today's dollar and are approximate,based on
conceptual design.
ROW costs are not included.It is assumed the City of
Renton will provide their Panther Creek wetland
property for the project.
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304 What are the implementation/permitting considerations?
305
306 The draft PCWRP has been reviewed by the
307 City of Renton and an endorsement of the
308 Concept obtained by WSDOT. The draft
309 PCWRP will be reviewed by the Multi-agency
310 Permitting Team (MAP Team), and the
311 appropriate Tribes. Early coordination with the
312 agencies and the Tribes is critical to determine
313 their support for a watershed-level Plan that
314 could be permitted in stages as highway i
315 construction stages are built.
316 A final AGREEMENT between the City of
317 Renton and WSDOT for concept
318 implementation will need to be reached.
319 WSDOT ownership of the Concept sites is
320 limited to WSDOT right-of-way. The City of
321 Renton owns or has easements for areas
322 located within the Panther Creek wetlands.
323 . Approval for the proposed stormwater
324 management approach is needed from the
325 MAP Team.
326 0 Construction stages will be identified as
327 additional funding is obtained. Stream
328 mitigation, based on the PCWRP, will be
329 identified, as practicable, for each construction
330 stage.
331 . The current stream rehabilitation area
332 estimates in this plan are preliminary and
333 conceptual. It is important to note that this
334 plan is not intended to be a stream mitigation
335 plan for permitting purposes. This is a concept
336 plan and first step toward thoughtful planning
337 for the implementation of stream mitigation
338 projects for this section of the 1-405 Corridor.
339 Stream mitigation plan reports and final
340 designs (plans, specifications and estimates)
341 are still required for the opportunities identified
342 herein for permitting requirements.
343 . Local, state, and federal permits as identified in
344 this plan will need to be obtained for each
345 construction stage.
346 . Coordination with King County Drainage
347 District No. 1 would be required for work on
348 Lower Springbrook Creek.
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INTRODUCTION
349 Easements may be required from private
350 property owners and have not been accounted
351 for in the planning level cost estimate.
352 WSDOT intends to provide wetland mitigation
353 in this portion of the 1-405 Corridor by debiting
354 credits from the Springbrook Creek Wetland
355 and Habitat Mitigation Bank.
356 Schedule considerations
357 WSDOT is currently preparing the
358 Environmental Assessment (EA) for the
359 Tukwila to Renton Improvement Project
360 (Tukwila to Renton). Stream mitigation for the
361 highway improvement effects on Panther
362 Creek and other tributaries to Springbrook
363 Creek will be addressed in the EA. If
364 approved, the PCWRP will be used to identify
365 stream mitigation for Tukwila to Renton effects
366 in the Panther and Springbrook sub basins.
367 Timely approval of the PCWRP by the spring
368 of 2007 will be necessary for completion of the
369 Tukwila to Renton EA, which is planned for
370 release in the fall of 2007.
371 The first stage of Tukwila to Renton roadway
372 construction will be the 1-405, 1-5 to SR 169
373 Stage 2 widening and SR 515 Interchange.
374 This stage is planned for construction in late
375 2008.
376 The HOV flyover ramps are part of the
377 Regional Transportation Improvement District
378 (RTID) funding which is pending public vote,
379 anticipated in the fall of 2007. The remainder
380 of the Tukwila to Renton highway
381 improvements and other Master Plan
382 improvements are unfunded at this time and no
383 funding timeline is set. The stream mitigation
384 for construction of the HOV flyover ramps
385 could be the first phase of implementation for
386 the PCWRP.
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INTRODUCTION l
387
i
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EXISTING CONDITIONS
388 EXISTING CONDITIONS
389 What watershed is being studied?
390 Panther Creek and Springbrook Creek are sub basins
391 located within the Green/Duwamish and Central Puget
392 Sound Watershed (Water Resource Inventory Area
393 [WRIA] 9). Panther Creek flows 3.4 miles from its
394 What is a Water Resource Inventory Area headwaters at Panther Lake to its confluence with
395 (WRIA)? Springbrook Creek. The Panther Creek wetlands
396 Washington State is divided into 62 WRIAs (PC" are approximately one-half mile upstream of
397 for water and aquatic-resource management the confluence with Springbrook Creek. The creek
398 issues. A WRIA may include more than one enters the wetlands east of SR 167 at the south end
399 watershed. However, the terms"WRIA"and and flows through a roadside wetland ditch and under
400 "watershed" are frequently used SR 167, at the SW 23rd Street culvert before its
401 interchangeably. confluence with Springbrook Creek. Springbrook
402 Creek drains to the Black River Pump Station (BRPS)
403 and eventually to the Green/Duwamish River. Exhibit
404 3 shows the existing conditions within the PCW to the
405 confluence with Springbrook Creek.
406 These sub basins are located within the Green River
407 Valley which has been greatly altered over the last
408 century. Historically, the extensive forested swamp
409 that covered much of the valley was cleared, diked,
410 drained, and converted to wet soil agricultural crops.
411 Rapid urbanization in the Green River Valley since the
412 mid 1960s has displaced agriculture with urban fill for
413 development.'
414 What are the limiting factors in the watershed?
415 The Panther Creek Watershed Rehabilitation Plan is
416 considered a watershed-level stream mitigation effort
417 because it considers habitat improvements throughout
418 much of the Panther Creek sub basin and in the lower
419 Springbrook Creek sub basin.
420 An important requirement of watershed-level
421 mitigation effectiveness is to understand the factors
422 limiting salmonid production within the watershed.
423 Past scientific literature was reviewed to determine
424 limiting factors for salmonid production in the
425 watershed. A key document found during this search
426 was Harza (1995), which contains a limiting factors
427 analysis for the Springbrook Creek sub basin.
P-9/Panther Creek Project Wetlands Inventory. The Coot Company. June 29, 1989.
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428 Panther Creek is a tributary to the Springbrook Creek
429 subbasin. Although the Harza report did not include
430 Panther Creek in its report scope, the analysis is
431 relevant due to the similar nature of Panther Creek to
432 other tributaries of Springbrook Creek, including
433 Garrison and Mill Creeks. In 2000, King County
434 provided a limiting factors analysis for the Springbrook
435 Creek subbasin that also references Harza (1995).
436 Harza's work served as the basis for the 2000 report
437 to define limiting factors. The most recent effort, King
438 County, 2005, is a summary of the earlier King County
439 work.
440 The following is direct quote from King County (2000)
441 that summarizes the limiting factors analysis for the
442 Springbrook Creek subbasin:
443 . Historically, it is believed that these creeks
444 were important areas of refugia to anadromous
445 salmonids that reared year round in the Green
446 River basin.
447 0 Water quality is degraded throughout much of
448 this subbasin.
449 . There is no functioning riparian habitat
450 throughout the lower reaches of Mill and
451 Springbrook Creeks. This absence of this
452 habitat contributes to the lack of stream
453 channel diversity, complexity, and ultimately
454 successful salmonid rearing capabilities.
455 . The Black River Pump Station is a partial fish
456 passage barrier and does not meet current fish
457 screening criteria. Adult salmonids that
458 migrate upstream of this structure cannot
459 migrate back into the mainstem Green River
460 because of facility design.
461 There are several known barriers to adult
462 salmonid passage in Springbrook, Mill, and
463 Garrison Creeks. Some of these barriers are
464 seasonal and/or dependent on annual
465 precipitation patterns.
466 Degraded water quality throughout the lower
467 reaches of Springbrook and Mill Creeks
468 adversely impact adult Chinook and coho
469 reproductive success along with cutthroat and
470 steelhead juvenile survival.
471 King County (2005) includes the Springbrook Creek
472 subbasin as a subset of the larger Lower Green River
473 subwatershed. For this larger area, the key salmon
474 habitat needs will:
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475 • Protect and restore side channels, off-channel
476 wetlands, tributary mouths, and pools that
477 provide shelter and habitat complexity for
478 young salmon;
479 • Protect and restore natural sediment
480 movement by reconnecting sediment sources
481 to the river;
482 . Preserve groundwater inflow from the historical
483 White River channel;
484 • Modify the Black River Pump Station to
485 improve fish passage.
486
487 The above discussion of limiting factors for salmonid
488 production in the Springbrook and Lower Green River
489 subwatershed is applicable to the Panther Creek, as a
490 tributary to Springbrook Creek. Hydrologic analyses
491 conducted for this planning effort revealed low stream
492 flows in Panther Creek as another important limiting
493 factor (see Appendix C— nhc Memorandum, February
494 2006). Modeling results showed stream flows were
495 essentially 0 cubic feet per second (cfs) in the east
496 fork of Panther Creek in May through August, due to
497 the dispersed flows across the alluvial fan that has
498 formed where Panther Creek flows onto the valley
499 floor. This information is considered in the stream flow
500 management planning for concept development in the
501 next chapter.
502 What is the current status of wetlands?
503 Washington State Department of Transportation
f 504 (WSDOT) performed wetland reconnaissance on the
505 approximately 65-acre PCW complex.
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506 Panther Creek Wetlands west of SR 167
507 The 6.5 acre wetland west of SR 167 is a scrub-shrub
508 What do the wetland categories mean? wetland confined to a long, narrow depression parallel to
509 SR 167. Rated as a Category III wetland, willow,
510 Wetland categories described in the Washington State Wetland Rating System for Himalayan blackberry, and reed canarygrass dominate
511 Western Washington State—Revised (Hruby the wetland. The west fork of Panther Creek flows
512 2004)rate wetlands based on uniqueness, through a culvert under SR 167 and provides hydrology
513 type, and functions. These categories are to this wetland.2
used to determine the level of mitigation
required when projects affect them. The two
514 categories that apply for the wetlands Panther Creek Wetlands east of SR 167
covered by this plan are:
515 The 58.5-acre wetland to the east of SR 167 is a
516 • Category 11 wetlands provide high levels depressional wetland that is categorized as a Category
517 of some functions and are difficult, II under the state rating system and a Category I under
though not impossible to replace. 2
518 the City of Renton rating system. Historically, the
519 • Category III wetlands provide moderate wetland was likely a more riverine-type associated with
520 levels of functions. They have been the floodplain of Springbrook Creek and the historic
disturbed and are often less diverse or E
521 more isolated from other natural floodplain of the Green/Duwamish River. The creek
522 resources in the landscape than and river are now separated from the wetland by
523 Category 11 wetlands. levees and urbanized/industrialized floodplain
524 development. The wetland relies on seasonally
525 elevated groundwater levels, perennial flows from
526 Panther Creek east fork, and hillside drainages and
527 seeps from the Talbot Hill to the east for its hydrology.3
528 The PCW extend east from the toe of the SR 167 road
529 fill to the toe of the forested slope (Talbot Hill). An
530 Olympic gas pipeline corridor runs east-west through
531 the complex at SW 23rd Street and parallel to SR 167
532 in vicinity of SW 19th Street (Exhibit 3). The pipeline
533 corridor's berm physically divides the wetland into two
534 :b �.< areas: north and south. SR 167 limits the outflow of
535 water from the Panther Creek wetland to three
536 „. culverts beneath SR 167: north (SW 19th Street),
537 central (SW 23rd Street), and south (SW 34th Street).
538 An Olympic gas pipeline corridor divides
the Panther Creek wetlands east of SR 167
I
2 1405, Renton Nickel Improvement Project, 1-5 to SR 169. Wetland Discipline Report.WSDOT. December 2005.
3 WSDOT Panther Creek Wetlands Assessment. Jones&Stokes. October 19, 2005.
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EXISTING CONDITIONS
Cascade Trail (H)
t, `J9'''
"' _ South Wetland
Springbrook Wetlands IM113
Trail (T)
(' r Panther Creek'
rail (S)
�' f „may; •-• - .:-' '
t . No rth Wetland,t, ..' . - - =_- -'� ®'ems.;�.r`� � EJ� -•� �•• - �",�r -;� •�, A '.:��;
t
i
- - ' ' a � r � 'I. a,•.
..
; a
4:
PEM
41
Wetland 1
r,
ti: r •c
- �•:•lam .ry - _ .. � � ..++.+f.....,�•,,,.. 'r.—
F a
y
I
.�
f
�I �• _.••j � �_,._. �. --ie , _ ..n. - hY �..�..,Y.._.. .-�Y"`r!'•fr` �. r k►1r-t
_ Wetlani 2L =
l� •1 • �a , �'- c-�sue• --!^" � •-
Legend
i �• ' Wetland Vegetation Communities:
Existing Contour(2 FT contour interval)
Utilities-Gas,Oil,Telecommunications PEM(canarygrass): palustrine emergent,monoculture
of reed canarygrass.
Utilities-Water,Sewer PEM(cattail): palustnne emergent,patches/monoculture
Wetland 4
of common cattail.
FAA Boundary(10,000 Feet)
Springbrook Trail (1) ' Streams(Open Channel PEM Canary rasa Cana with pat palustnne emergent-
) reed canarygrass matrix with patches/areas of cattail.
l — Streams(Piped) PSS1: palustnne scrub-shrub broad-leaved deciduous
Planned Trails-City of Renton thickets of shrubby willow,with various understory species.
(1990,1992)
a, PF01: palustnne forested broadleaf deciduous wetland
Misc.Wetlands(approx.) dominated by Pacific willow trees with Oregon ash and
black cottonwood trees and dense shrub layer of shrub
willows and various other shrubs and herbs.
Panther Creek Wetlands(approx.)
Extent of wetland vegetation communities are approximate
City Owned Properties/Easements and based on field investigations conducted October 6th and
10th,2005 by WSDOT.
0 200400 4ee
539
540 Exhibit 3. Panther Creek Wetlands Existing Conditions and Planned City Trails (City of Renton, 1990 and 1992)
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541 ,
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EmSTING CONDITIONS
542
543 The hydrologic functions the PCW perform include flood
544 flow alteration, sediment removal, nutrient and toxicant
545 removal from stormwater runoff, and erosion control and
546 shoreline stabilization. The biological functions the PCW
547 performs are production of organic matter and its export,
548 general habitat suitability, habitat for aquatic
549 invertebrates, habitat for amphibians, habitat for wetland
550 associated mammals, habitat for wetland associated
551 birds, general fish habitat. The social value for the PCW
552 is unique heritage and richness because it has been
553 identified by the City of Renton as having local
554 significance.4
555 North Wetland
556 The North Wetland covers approximately 13 acres and
557 is divided from the south wetland at SW 23rd Street.
558 This forested and scrub-shrub wetland comprises less
559 than one third of the total PCW. This portion has
560 seasonally elevated groundwater levels and likely
561 receives some overbank surface flows from Rolling
562 Hills Creek, Thunder Hills Creek, and seeps from
563 Talbot Hill. Saturated soils and areas of standing
564 water appear to be present throughout most of the
565 year. The forested and scrub-shrub communities in
566 this wetland are high quality. These wetland
567 The North Wetland has dense mature communities are experiencing water levels that may
568 vegetation be very near their upper limits of tolerance for
569 sustaining the types of wetland vegetation currently
570 found here. This is based upon the degree of soil
571 saturation observed during October 2005 site visits
572 and our general knowledge of the physiological
573 tolerances to inundation of the plant species observed
574 on the site.5
575 The North Wetland is a mature, forested wetland
576 community dominated by dense vegetation. Species
577 include Pacific willow, Oregon ash, black cottonwood,
578 red-osier dogwood, Douglas spirea, Scouler's/Sitka
579 willow. The eastern buffer is dominated by native
580 upland tree and shrub species. There presently is no
581 western buffer because of SR 167.
4 1-405, Renton Nickel Improvement Project, 1-5 to SR 169. Wetland Discipline Report.WSDOT. December 2005.
5 WSDOT Panther Creek Wetlands Assessment. Jones&Stokes. October 19,2005.
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EXISTING CONDITIONS
582 South Wetland
583 At approximately 45 acres, the South Wetland
584 comprises more than two thirds of the PCW.
585 What are invasive plant species and why Seasonally elevated groundwater levels, direct flow
586 are they a problem? from Panther Creek, and seeps and drainages from
587 Invasive plant species are those that do not Talbot Hill provide hydrology to this wetland. Two
588 naturally grow in a particular area, but thrive primary culverts cross under SR 167 in the South
589 once introduced. These plants are adaptable Wetland. The largest culvert, 72 inches in diameter, is
590 and aggressive, and they have a high at SW 23rd Street. Saturated soils and areas of
591 reproductive capacity. They can outcompete standing water appear to be present throughout most
592 native plants and take over plant of the year.
communities, disrupting the natural functions.
593 The South Wetland has a range of wetland
594 communities. Approximately 1,200 feet south from the
595 Olympic pipeline berm is a 10-acre scrub-shrub
596 community characterized by Pacific willow and
597 Scouler's/Sitka willow with Nootka rose and Douglas
598 spirea in small patches. Yellow-flag iris dominates the
599 understory.
600 This community abruptly changes to a 27-acre
601 emergent wetland community from SW 27th Street
602 approximately 3,400 feet southward. It is dominated
603 by reed canarygrass, common cattail, and small
604 thickets of willow/rose/spirea interspersed along the
605 eastern toe of the slope. At this point, South Wetland
606 (Exhibit 3) meets the alluvial fan for Panther Creek.
607 From here, the wetland transitions to an 8-acre
608 forested wetland community. It is dominated by
609 Pacific willow, red alder, black cottonwood trees, with
610 an understory of reed canarygrass, yellow-flag iris,
611 and some scattered native herbaceous and shrub
612 species.
613 Reed canarygrass dominates the emergent The scrub-shrub wetland has an excellent density and
614 vegetation community in the South diversity of native scrub-shrub wetland community
615 Wetland type. The forested wetland in the extreme south end
616 has varying degrees of habitat diversity. However, the
617 large emergent wetland community, which comprises
618 almost 60 percent of the South Wetland, has low
619 habitat diversity and is dominated by monocultures of
620 reed canarygrass and common cattail.6
6 WSDOT Panther Creek Wetlands Assessment. Jones&Stokes. October 19, 2005. I
i
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621 What are the constraints to stream rehabilitation within the Panther
622 Creek Wetlands?
623 The majority of PCW outside of the WSDOT right-of-
624 way (ROW) are located on property owned by the City
625 of Renton as shown in Exhibit 3. The City has
626 drainage easements for the remaining parcels up to
627 elevation 20 (datum NAVD 88). Drainage easements
628 don't preclude the rehabilitation activities proposed by
629 this plan. Further investigation is required to verify
630 that none of the parcels currently have recorded
631 easement restrictions.
632 Underground and overhead utilities bisect the
633 wetlands (east-west) at three locations. Beginning at
634 the project's north end, the following utility crossings
635 occur:
636 . City water main at SW 19th Street
637 • Olympic Pipeline utility berm at SW 23rd Street
638 • King County Sewer line at approximately SW
639 39th Street
640 The King County sanitary sewer line is 18 inches in
641 diameter. Further investigation is required to confirm
642 location and depth of this line from Metro as-built plans.
643 The City of Renton (City of Renton 1990, 1992) has
644 planned trails in the vicinity (Exhibit 3), including:
645 major trails— Springbrook Trail (1) and the Cascade
646 Trail (H); and minor trails— Springbrook Wetlands Trail
647 (T) and the Panther Creek Trail. The City has asked
648 WSDOT to include the Springbrook Trail (1) as part of
649 this project and has also asked that this project not
650 preclude future construction of the other trails.
651 Federal Aviation Administration (FAA) guidelines
652 restrict open water areas within a 10,000-foot
653 boundary of the Renton Municipal Airfield because of
654 safety concerning aircraft encountering birds. This
655 restriction applies to those areas northward of the FAA
656 boundary shown in Exhibit 3. The boundary bisects
657 the wetlands approximately 400 feet south of SW 23rd
658 Street.
659 Slope stability analysis was conducted by WSDOT for the
660 PCW. Initial hydrologic analysis performed for this project
661 considered raising water levels 2 feet within the wetland.
662 This scenario is no longer being considered, however, the
663 geotechnical analysis for it is presented at the City of
664 Renton's request. The Preliminary Geotechnical
665 Investigation—Panther Creek Watershed Restoration
666 Project, November 3, 2005 (Appendix A), indicates that
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667 the slopes would be stable even if the groundwater level is
668 raised another 2 feet in the wetland.
669 What is the current status of the streams & fish habitat in the
670 watershed areas proposed by this concept plan?
671 Waterbodies located in the watershed project area
672 include Springbrook Creek, Panther Creek and its
673 associated wetland system, Rolling Hills Creek, and
674 Thunder Hills Creek. All of these streams ultimately
675 flow into the Green/Duwamish River. Exhibit 4
676 identifies the stream reaches evaluated for the
677 PCWRP.
678 Exhibit 5 summarizes the habitat conditions for the
679 stream reaches shown in Exhibit 4. The following
680 sections describe each stream.
681 Springbrook Creek
682 Springbrook Creek is the only known waterbody within
683 the watershed project area to contain Chinook salmon,
684 What is the Endangered Species Act? a species listed as threatened under the Endangered
685 Congress passed this act in 1973 to govern Species Act (ESA). Other species listed as threatened
686 how animal and plant species whose or endangered under ESA, such as bull trout and Dolly
687 populations are dangerously in decline or Varden, are not known to occur within the watershed
688 close to extinction will be protected and project area. Chinook salmon critical habitat within the
recovered.
689 watershed project area includes Springbrook Creek.
690 Physical conditions
691 Springbrook Creek is a receiving waterbody for
692 Panther, Rolling Hills, and Thunder Hills creeks.
693 Riparian habitat within Springbrook Creek does not
694 meet the National Marine Fisheries Service (NMFS)
695 criteria for properly functioning habitat and is
696 considered a limiting factor to natural salmonid
697 production.? Springbrook Creek is known to be used
698 by coho salmon, Chinook salmon, cutthroat trout, and
699 steelhead trout for spawning and rearing,$ however
700 Springbrook Creek at confluence with fish count information is still missing from the WRIA 9.
Panther Creek
7 Salmon and Steelhead Habitat Limiting Factors Report for the Cedar—Sammamish Basin (Water Resource Inventory
Area 8), Washington Conservation Commission. Kerwin. 2001.
8 Inland fishes of Washington.Wydosky and Whitney. 1979.
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 18
• r •
AL
Springbrook ' Thunder�H ill s'CrF
�! Creek ■
Rolling
*� Hills Creek -
�,. �, �' r RY VVAY a
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a
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r
Gilliam.*
Creek .1 QCL
=
r
Rollin Hills t
_Tributary �i g• 1
Creek
r " Roll nTHills Creek t n
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� Panther Creek
_ rr
jLU
m - Q C
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,F liner Or � -)3 � 4w
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ioil tf
» _
_
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i
PREI.IMINARI'DRAFT FOR MUI"TI-AGENCI'PERMITTING TEAM(1MAPT)REVIENV
EXISTING CONDITIONS
704 Fish passage
705 What are fish passage barriers? The BRPS is located upstream of the confluence
706 Fish passage barriers prevent or limit the between Springbrook Creek and the Green/Duwamish
707 ability of fish to move upstream past the River. The BRPS controls outflows from Springbrook
708 barrier. The fish passage standards Creek into the Black River, prevents flows on the
709 established by the Washington Department of Green River from backing up into Springbrook Creek
Fish and Wildlife in 2003 describe fish
710 barriers as"complete", "temporal", or"partial". during storm events, and provides a means of
711 releasing flood flows from the Springbrook Creek
712 system when the Green River has high flows as a
713 result of storms. The BRPS has been identified by the
714 Salmon Enhancement Plan9 and others as being in
715 need of fish passage improvements. A total of 262
716 upstream migrating adult salmonids were counted after
717 passing the BRPS during the 1994-1995 run. Of
718 these, 14 were Chinook salmon and 229 were coho
719 salmon. Overwintering salmonids observed during this
720 run included 84 juvenile coho salmon, 198 rainbow
721 ,4. trout and 4 cutthroat (Harza 1995). King County is
722 presently considering a proposal for fish passage
723 improvements to the BRPS which would in turn
724 improve fish passage to lower Springbrook Creek.
725 . . a Panther Creek
726 East Fork— Downstream of SR 167
727 Physical conditions
728 "`"°`''L' `"y`" Four culverts occur along the east fork of Panther Creek
729 Culvert outfall (underwater) under East from SR 167 to the confluence with Springbrook Creek.
730 Valley Road to SW 23rd Street open The first culvert moving downstream, the SR 167 cross
731 channel culvert, is a combination fish ladder and conveyance
732 structure between the PCW and the west side of SR 167.
733 The cross culvert is about 210 feet long, and is a 72-
734 inch-diameter pipe.
735 From the SR 167 cross culvert, Panther Creek flows
736 through another 72-inch-diameter pipe (approximately 70
737 feet long) under East Valley Road. This culvert outfalls
738 to an open channel system along SW 23rd Street. The
739 channel is primarily straight with few pools and limited in-
740 stream structures. A significant portion of the right bank
741 of this segment of Panther Creek borders an access road
742 that limits both riparian buffer establishment and a
743 connection with the creek's floodplain. Significant
744 portions of the left bank border are forested wetlands.
9 King County. 2005.
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 20
PRELIMINARI DRAFT FOR MULTI-AGENCY PERMITTING TEAM(MAPT)REVIEW
EXISTING CONDITIONS
745 Panther Creek crosses under Lind Avenue in twin arch
746 culverts that outfall to a pool. From here, Panther Creek
747 crosses under high pressure petroleum pipelines in a set
748 of culverts, a box culvert and a pipe. Installed in 1998,
749 these two culverts are 84 feet in length and are owned by
750 the Olympic Pipeline Company. From these two
751 culverts, the creek flows in an open channel with
752 - _ k —- significant portions of the left bank bordered by forested
753 k' ` "` i wetlands until the creek reaches its confluence with
754 Springbrook Creek.
755 Fish passage
756 ��, `' This portion of Panther Creek likely supports the same
757 species of fish as are found in Springbrook Creek.
758 The lower Lind Avenue culverts on Panther The fish ladder was evaluated for only one flow (34
759 Creek cubic feet per second (cfs)). This flow is estimated as
760 a 2-year peak storm flow. At this flow, it failed to meet
761 the suggested fish passage criteria for 3 feet of
762 freeboard, fishway bends, and depth over the weirs.
763 This structure may be a partial barrier to fish
764 passage.10 However, LaRivierell stated that "the fish
765 ladder appears to function as intended regarding
766 juvenile and adult fish passage; it conveys flow year
767 round, there are no drop barriers, and velocity barriers
768 are only temporal." The 210-foot cross culvert under
769 SR 167 appears to meet Washington State
770 Department of Fish and Wildlife (WDFW) fish passage
771 requirements.
772 Compared to the WDFW fish passage criteria for high
773 flows, velocities in the East Valley Road culvert at SW
774 , ,, 23rd Street are lower than the maximum allowable and
775 `, � ' a flow depths are greater than the minimum allowable.
776
Due to the downstream backwater, flow depths will be
777 *,, + adequate in low flow conditions. Consequently, it
778 appears that the culvert is not a barrier to fish passage
779 ti:` for a wide range of flows and no modifications are
780 ` '' needed at this time.12
781 4'.'• : `' Flow depth is adequate under low flow conditions
782 Y . ,r because the Olympic Pipeline culverts are submerged.
783 ', j `' The velocities and depths are acceptable according to
784Y the WDFW fish passage criteria for high flows.
785 •ra:�.. However, LaRiviere10 stated that underwater culverts
786 This fish ladder on Panther Creek east fork can be partial barriers to both upstream and
787 is a partial fish passage barrier downstream movement of fish because of the
10 Fish Passage at Evaluation at Central Panther Creek Outlet. WSDOT. 2006.
11 Panther Creek Fish Passage Memorandum. LaRiviere. 2006.
12 Fish Passage at Selected Panther Creek Culverts. RW Beck. 2006.
1-405 N1 ater Resource Initiative at Panther Creek NN etlands
Panther Creek Watershed Rehabilitation Conceptual Plan 21
PRELIMINARN,DRAFT FOR MULTI-AGENCv PERMITTING TEAM(NIAPT)REVIEH'
EXISTING CONDITIONS
788 submergence. Relocation of the Olympic pipelines
789 would improve fish passage. However, relocation
790 would be costly, and is a low priority to improve fish
791 passage in Panther Creek.12
792 { y
Subject to further analysis, there are no known
793 complete barriers that would preclude fish passage
794 between the confluence with Springbrook Creek and
795 the Panther Creek wetland complex."
796 East Fork - upstream of SR 167 (South
797 - Wetland)
798 Physical conditions
799 Panther Creek flows from Talbot Hill forming an
800 alluvial fan on the valley bottom in the PCW. At the
801 Panther Creek mainstem fork; east fork is upstream end of the alluvial fan, Panther Creek splits
802 to left and west fork to right of photo into two forks, hereafter referred to as the east and
803 west fork. Typical of alluvial geomorphology, Panther
804 Creek flows through this area are dynamic. WSDOT
805 reconnaissance between October 2005 and March
806 2006 observed the majority of flow shift from the east
807 fork to the west fork. Also, the alluvial fan is
808 characterized by numerous side channels, braids and
809 rivulets that change course with flood events. At the
810 confluence with the wetland, the east fork of Panther
811 Creek flows northerly through the wetland in a
812 roadside ditch along the east side of SR 167 for
813 approximately one mile before it outlets at the culvert
814 under SR 167. This portion of Panther Creek likely
815 supports the same species of fish as are found in
816 Springbrook Creek.
817 Little salmonid spawning habitat exists in Panther
818 Creek throughout most of the wetland area; however,
819 suitable spawning habitat is available upstream of the
820 alluvial fan.
821 Stream habitat in this reach is poor for the riparian
822 Panther Creek east fork upstream of zone width because of proximity to the road fill on the
823 SR 167 in South Wetland left bank as shown on Exhibit 5.
824 Fish passage
825 Panther Creek upstream of SR 167 is considered
826 accessible by fish and other aquatic species from
827 culverts under SR 167 (e.g., SW 23rd Street). Despite
828 the absence of a distinct stream channel through the
829 wetland between the fish ladder and the alluvial fan
830 area, there are no known barriers to fish passage
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 22
PRELIMINARI,DRAFT FOR NIULTI-AGENCY PFRMITTINc TEAM(MAPT)REYIENY
ExISTING CONDITIONS
831 within the PCW.13 Currently, fish passage in this area
832 is likely limited to flood events.
833 West Fork— downstream of SR 167
834 Physical conditions
835 The west fork of Panther Creek flows underneath
836 SR 167 in two culverts (one is the main crossing and
837 one is overflow crossing). The creek outlets on the
838 west side of SR 167 into a roadside ditch dominated
839 by reed canarygrass. It then turns westerly between
840 two businesses and flows through a managed, turf-
841 lined biofiltration swale before entering a City
842 stormwater system under East Valley Road. The
843 remaining 4,000 linear feet (LF) run primarily in a pipe
844 to the confluence with Springbrook Creek. What little
845 open channel does exist has no native riparian canopy
846 and completely lacks in-stream structures.
847 Fish passage
848 Due to the extent of piped channel combined with
849 extensive commercial development, the west fork of
850 Panther Creek is likely a complete barrier to upstream
851 fish passage.
852 Additional upstream barriers to fish passage in the
853 Panther Creek system
854 Upstream of the Panther Creek wetland complex,
855 WSDOT performed field reconnaissance to determine
856 whether other fish passage barriers existed in higher
857 portions of the watershed and at selected Panther
858 Creek culverts. Areas of concern were based on a
859 1989 Watershed Company Report that identified
860 several locations of concern for fish habitat and
861 passage. The field reconnaissance, described in RW
862 Beck (2006), identified three likely upstream barriers to
863 fish passage:
864 . Talbot Road culvert
865 . Carr Road culvert
866 . An earthen dam upstream of Carr Road
13 Fish Habitat Memorandum. Prepared by Derek Koellmann,Anchor Environmental. 2006.
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 23
PRELINI1NARl DRAFT FOR MULTI-AGENCY PERMITTING TEAM(MAPT)REVIEW
EXISTING CONDITIONS
867 '-` Panther Creek crosses under Talbot Road in a 120-foot-
868 long, 36-inch-diameter culvert. The pipe inverts have
869 been scoured away for about 3 feet on both the upstream
870 v "' � ,�' n y and downstream ends. The pipe goes through a large
871 rf,• ,,+ �� ; roadway embankment and is 27 feet below the road
872 `�, `Y�` surface. The drop from the culvert's downstream outlet
a�''E/ ,M
873 ,� " to the stream is approximately 4.2 feet. This drop from
874 the culvert outlet to the stream acts as a barrier to
875 ` upstream fish passage as do the high velocities and low
µ,�876 �' flow depths in the pipe. 14
877 s '` �►°*•-'' � �� '' Panther Creek crosses under Carr Road in a 150-foot-
878 Talbot Road culvert fish barrier at long, 6-foot-diameter culvert. The overall gradient is
879 downstream end 4.5 percent and the culvert goes through a road
880 embankment and is approximately 30 feet below Carr
881 Road. The culvert outlet has a drop of about 3 feet
882 l into an irregular series of cascades that drop into the
883 stream channel. From the culvert through the
884 IN, ` cascades, the creek drops 7 feet over a distance of 25
885 ;` feet. This creates difficult conditions for upstream
886 passage for most life stages of fish. This outlet is
887 considered a barrier to upstream fish passage.14
888 , ::' l' Approximately 120 feet upstream of the Carr Road
889 �. N 1 culvert, Panther Creek flows over an 11-foot-high
890 earthen and concrete dam. The dam has a trapezoidal-
891 '`` shaped concrete spillway that is failing. The dam and
892 Carr Road Culvert fish barrier at spillway are barriers to upstream fish passage.14
893 downstream end There are no other documented barriers to fish passage
894 between here and Panther Lake. The ravine upstream
895 t _ ka I of SE 192nd Street is in good condition with a forested
896 riparian canopy, instream logs, pools and spawning
897 gravel in some places. 15
898 t Rolling Hills Creek
899 Physical conditions
900 .•q, Rolling Hills Creek flows from the Rolling Hills
901 subbasin located south of 1-405 as shown in Exhibit 4.
902 = Resident fish species likely to occur in the reaches of
903 - Rolling Hills Creek and its unnamed tributary within the
904 Concrete earthen dam fish barrier, 120 feet project area include sculpin and three-spine
905 upstream of Carr Road culvert stickleback.16
906 Approximately 1,000 feet south of the project area,
907 Rolling Hills Creek flows through a series of culverts
14 Fish Passage at Selected Panther Creek Culverts. RW Beck. 2006.
15 Panther Creek Salmonid Fish Habitat Restoration. The Watershed Company. 1989.
16 Inland fishes of Washington. Wydosky and Whitney. 1979.
1-405 NN ater Resource Initiative at Panther Creek NN etlands
Panther Creek Watershed Rehabilitation Conceptual Plan 24
PRELIMINARl DRAFT FOR MUI.'rl-AGENCI PERSIITTING TEAM(MAPT)REN'IENN
ENISTING CONDITIONS
908 under several commercial parking lots to where it
909 ultimately daylights on the north side of 1-405 into an
910 open channel between the Renton Cinema 8 parking
911 lot and 1-405. The creek then flows westerly under the
912 1-405/SR 167 interchange, outlets into an open
913 channel along the south side of the interchange, and
914 then into another culvert system beginning at SR 167
915 and continuing to its confluence with Springbrook
�,, '' '' Creek.
917 �`'� Stream habitat in this reach is poor for every habitat
�,. ter. ':�
918 - _ i1,_+ parameter observed except for canopy cover and pool
919 w�� - �-�' habitat, see Exhibit 5.
920 Rolling Hills Creek on north side of 1-405 Fish passage
921 No anadromous fish species are reported to occur in
922 Rolling Hills Creek or its unnamed tributary.17 This is
923 likely due to two downstream fish passage barriers.
924 What are Anadromous vs. Resident Fish? The Rolling Hills Creek culvert under the 1-405/SR 167
925 interchange is a partial fish passage barrier. The SW
926 stream Anadromous risk are born in freshwater 19th Street culvert system between SR 167 and
phase in the ocean,927 streams, rivers, a n, and return to their lakes, spend their adult Springbrook Creek has significant length to be
928 original waters to spawn. considered a complete fish passage barrier.18
Resident fish spend their entire lives in
929 freshwater systems and do not migrate into Thunder Hills Creek
saltwater environments.
930 Physical conditions
931 The headwaters of Thunder Hills Creek are located to
932 the southeast of 1-405. Resident fish species likely to
933 occur in the upper reaches of Thunder Hills Creek
934 include cutthroat trout, sculpin, and three-spine
935 _ stickleback."
936 ' Upstream of 1-405, Thunder Hills Creek flows in an
937 incised channel to where it crosses under 1-405
938 (Exhibit 4). After flowing under 1-405, it daylights into a
939 concrete outfall located directly behind Sam's Club.
940 After daylighting at the outfall, Thunder Hills Creek
941 combines with water flowing from a historic, now
942 abandoned coal mine. From the confluence of these
943 two flows, Thunder Hills Creek and the coal mine
944 runoff enter a three-sided concrete flume. The flume
945 Thunder Hills Creek in concrete flume on flows along the southeast edge of Sam's Club parking
946 north side of 1-405 lot and outlets into an open stream channel associated
947 with a wetland complex immediately east of Talbot
17 Distribution of Salmon and Trout Water Resource Inventory Area(WRIA)8 Lake Wash i ngton/Cedar/Sa m mamish
Watershed. KCDNR. 2001.
18 Panther Creek Watershed Restoration Project Existing Conditions Synopsis.Anchor Environmental. February 28,
2006.
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 25
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EXISTING CONDITIONS
948 Road South and north of 1-405. The creek then flows
949 west under Talbot Road and into a series of culverts
950 before it daylights and converges with Rolling Hills
951 Creek between the Renton Cinema 8 parking lot and
952 1-405.
953 Fish passage
954 Thunder Hills Creek shares the same barriers to fish
955 passage that are described for Rolling Hills Creek.
956
Exhibit 5. Stream Habitat Conditions Summary
Panther Creek East Fork — Panther
Habitat Springbrook Downstream of Upstream of SR 167 Creek West Rolling Hills Thunder
Parameter Creek SR 167 (South wetland) Fork Creek Hills Creek
DNR Stream S F F F F F
Type
Streambank Marginal Suboptimal Suboptimal Suboptimal Poor Optimal
Stability
Streambank
Vegetative Marginal Poor Marginal Poor Poor Poor
Protection
Riparian Zone Marginal Poor Poor Poor Poor Marginal
Width
Substrate Poor Poor' Poor Poor Poor Suboptimal3
Embeddedness
Canopy Cover Suboptimal Marginal Suboptimal Poor Marginal Suboptimal
LWD Poor Poor' Poor Poor Poor Marginal
Frequency
Pool Quality Suboptimal Marginal N/Az Marginal Suboptimal Marginal
Channel Marginal Poor Marginal Poor Poor Poor
Alteration -
DEFINITIONS
Optimal streams have stable banks,good canopy cover,a wide riparian zone,large woody debris(LWD)and a normal channel pattern,etc.
Suboptimal streams have moderately stable banks,average canopy cover,riparian zone and LWD and a normal channel pattern,etc.
Marginal streams have moderately unstable stable banks,below average canopy cover,an impacted riparian zone,LWD and a disrupted channel pattern,etc.
Poor streams have unstable banks,little canopy cover,an absence of LWD and severe channel alteration(e.g.,rip rap).
(For a full definition of these ratings,See Appendix B,Fish Habitat Memorandum,Anchor Environmental,2006.)
1. Due to the nature of the stream channel within the Panther Creek Wetland Complex,certain habitat parameters,such as substrate embeddedness and LWD,
are not readily applicable to the nature of the stream system and may be properly functioning based on the natural interaction between Panther Creek and its
associated wetland in this area.
2. No pools were found in the study reach.
3. A large portion of Thunder Hills Creek is contained in a concrete flume,and as such,the majority of the streambed is composed of concrete.
S=shorelines of the state;F=not classified as Type S,but are natural waters that have fish,wildlife,or human use.
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 26
PRELLN,IIN.ARY DRAFT FOR MITIM-AGENCY PERMITTING TEA-m(MAPT)REVIEW
ExiSTING CONDITIONS
957 What is the current status of water quality in Panther and
958 Springbrook Creeks?
959 During 2001 and 2002 Springbrook Creek and
960 Panther Creek were sampled as part of the Green-
961 Duwamish Watershed Water Quality Assessment.
962 Springbrook Creek was sampled in vicinity of its
963 mouth and downstream of 1-405. Panther Creek East
964 Fork was sampled east of SR 167 in the Panther
965 Creek Wetland. The median base flow water quality
966 values for temperature, dissolved oxygen and
967 dissolved copper from this sampling are shown in
968 Exhibit 6.
969 Chronic water quality problems in the Springbrook
970 basin include exceptionally low concentrations of
971 Dissolved Oxygen (DO), high turbidity, high levels of
972 fecal coliform bacteria, Total Suspended Solids (TSS),
973 and ammonia.19
974
Exhibit 6. 2001 and 2002 Springbrook Creek and Panther Creek median
base flow water quality values 20
QualityWater
Temperature Dissolved Oxygen
DissolvedLocation (degrees C) (mg/L)
Springbrook Creek 11.5 4.7 0.0011
Panther Creek 10.5 12.3 0.0012
975
976 State water standards for temperature define a
977 maximum 16.00 C in core salmonid rearing waters and
978 17.50 C in noncore salmonid rearing waters (as
979 determined on a seven-day average daily maximum).
980 State water standards require dissolved oxygen
981 concentrations exceed 9.5 mg/L in freshwaters
982 designated for core salmonid rearing and 8.0 mg/L in
983 freshwaters designated for noncore rearing.
984 Springbrook Creek is on the state's 1998 303(d) list as
985 impaired for temperature, DO and copper. King
986 County2l identified high temperature and low DO
19 Kerwin. 2001.
20 King County and Herrera. 2004.
21 King County. 2000.
I-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 27
PRELIMINARY DRAFT FOR MULTI-AGENCY PERMIITTING TEANI(MAPT)REVIEW
E:mSTLNG CONDITIONS
987 concentrations as a probable cause for the decline of
988 salmonids in Springbrook Creek.
989 What is the current status of stream flow diversions in the watershed?
990 Streams affected by diversions
991 Stream flows within this watershed have been altered
992 by diversions (City of Renton 1997), an important point
993 when considering a watershed rehabilitation plan.
994 Rolling Hills Creek, east of SR 167, has a flow split
995 (diversion) that can direct water into the north Panther
996 Creek wetland during flood conditions.
997 Panther Creek Stream flows can be split at the alluvial
998 fan that has formed where Panther Creek flows onto
999 the valley floor. For example, in recent years, more
1000 stream flow has been diverted into the west fork of
1001 Panther Creek (SW 34th Street system) and less into
1002 the east fork. More recently field observations
1003 confirmed that sedimentation in the alluvial fan has
1004 directed the majority of Panther Creek flows into the
1005 south Panther Creek wetland. A fish ladder was
1006 installed on the east fork of Panther Creek upstream
1007 of the SR 167 crossing. As part of this work, several
1008 SR 167 cross culverts were blocked in an effort to
1009 concentrate stream flow towards the fish ladder.
1010 Management of the stream flows at these locations is
1011 an important factor in development of the rehabilitation
1012 concept in the next chapter.
1013 What is the current status of wildlife in the watershed areas proposed
1014 by this concept plan?
1015 The wetlands and riparian corridors of the PCW have
1016 high quality habitat and support a higher abundance
1017 and diversity of wildlife compared to that provided by
1018 roadside and urban matrix habitats. The wetlands
1019 have several functions and values that are important
1020 to wildlife species such as providing shelter and
1021 foraging habitat for migratory and resident birds such
1022 as great blue heron, mallard duck, red-tailed hawk,
1023 and red-winged blackbird and small animals such as
1024 raccoons.
1025 Wildlife use of the wetlands is mainly limited to riparian
1026 bird species. Animals that rely on shallow marsh
1027 areas are restricted in number and variety, largely due
1028 to the lack of persistent, open water and low habitat
1-405 Water Resource Initiaths a at Panther Creep Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 28
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1029 diversity within the extensive stands of cattails and
1030 reed canarygrass.22
1031 Riparian corridors in this project area contain elements
1032 of both aquatic and terrestrial ecosystems. The riparian
1033 corridors typically support aquatic habitats and functions
1034 within the watercourse that they are associated.
1035 Streams and their associated riparian corridors
1036 frequently provide refuge and foraging opportunities and
1037 may provide an essential migratory route that links
1038 otherwise isolated wildlife populations.23
1039 No known terrestrial federally listed species or federal
1040 species of concern occur within the PCW as discussed
1041 in the Tukwila to Renton Improvement Project(1-5 to SR
1042 169—Phase 2) Upland Vegetation and KfiIdlife
1043 Discipline Report. No bald eagles occur within the
1044 PCW. For additional information on regulated species
1045 please refer to the Tukwila to Renton Improvement
1046 Project(1-5 to SR 169— Phase 2) Biological
1047 Assessment.
1048
22 P-9/Panther Creek Project Wetlands Inventory, June 29, 1989. The Coot Company.
23 Renton Nickel Improvement Project Upland Vegetation And Wildlife Discipline Report. WSDOT. 2005.
I-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 29
PRELIMINARY DRAFT FOR Mum-AGENCY PERNUTTING TEAM(MAPT)REVIEW
EXISTING CONDITIONS
I405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 30
PRELIMINARY DRAFT FOR MULTI-AGENCY PERMITTING TEAM(MAPT)REN'IEN
CONCEPT DEVELOPMENT
1049 CONCEPT DEVELOPMENT
1050 What are the I-405 improvements that this concept plan addresses?
1051 The PCWRP provides watershed-level stream
1052 `' ` mitigation for the effects to streams from the 1-405, 1-5
1053 to SR 169 Master Plan in the Panther Creek and lower
1054 Springbrook Creek watersheds. The 1-405/SR 167
1055 interchange reconfiguration and SR 167 realignment
1056 were reviewed to understand the effects (see before
1057 •_ and after figures, left). The proposed highway
1058 configuration minimizes these effects by using
1059 _ "stacked" freeway ramps within the interchange to
1060 �� reduce the roadway footprint.
1061 - WSDOT is currently preparing the Environmental
1062 Assessment (EA) for the Tukwila to Renton
1063 1-405/SR 167 Interchange "Existing" Improvement Project (Tukwila to Renton EA). As a
1064 result of the Tukwila to Renton EA, 1-405 Team
1065 engineers have estimated the effects to streams and
1066 wetlands from the Tukwila to Renton roadway
1067 footprint. Because the PCWRP is based on the
1068 Master Plan footprint (which does not have the same
1069 design detail as Tukwila to Renton), the 1-405 Team
1070 needed to understand the difference between the
1071 = Tukwila to Renton and Master Plan footprints.
1072 �_ The main differences between footprints for the 1-405
1073 :1,, _ `--� Master Plan and Tukwila to Renton Project are the
1074 - alignment of southbound (SB) SR 167 and the ramp
1075 connections between south and west segments of the
1076 interchange.
1077 1-405/SR 167 Interchange "Tukwila to In the Tukwila to Renton footprint, the SB SR 167 is
1078 Renton Project" reconstructed on a new alignment from about SW 27th
1079 Street to 1-405. In the Master Plan, SB SR 167 is
1080 I .: reconstructed on a new alignment from the SW 41 st
1081 Street off-ramp to just north of SW 27th Street and
1082 high occupancy vehicle (HOV) direct access ramps to
1083 SW 27th Street are constructed.
1084 �� Additional improvements to the 1-405/SR 167
1085 interchange included in the Master Plan but not in the
1086 Tukwila to Renton footprint include HOV direct
1087 / 1 -Ed"— connector ramps between the south and west legs of
1088 the interchange (northbound (NB) SR 167 to SB 1-405
1089 and NB 1-405 to SB SR 167), general-purpose
1090 (GP) direct connector ramp from NB SR 167 to SB I-
1091 1-405/SR 167 Interchange "Master Plan" 405, and HOV direct access ramps between 1-405 and
1092 Rainier Ave (SR 167).
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 31
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CONCEPT DEVELOPNIENT
1093 The 1-405 Master Plan will have a larger footprint than
1094 the Tukwila to Renton project in and around the SR
1095 167 and 1-405/ SR 167 Interchange area because of
1096 these additional improvements. Along SR 167, the
1097 additional realigning of SIB SR 167 increases the
1098 footprint along the west side of SR 167 from the
1099 SW 41 st Street off-ramp to just north of SW 27th
1100 Street. The new GP ramp from NB SR 167 to SIB I-
1101 405 increases the footprint along the east side of SR
1102 167 from about SW 27th Street to the north. The
1103 majority of this ramp is anticipated to be constructed
1104 as "above ground structure" to minimize the impacts
1105 on the Panther Creek Wetlands. The footprint of the
1106 west segment (leg) of the interchange will not increase
1107 as the additional ramps are constructed in median
1108 areas of the Tukwila to Renton project.
1109 What are the stream and wetland effects?
1110 The Master Plan will permanently affect approximately
1111 64,731 square feet of stream channel (below ordinary
1112 high water mark (OHWM)), approximately 5.48 acres
1113 of wetland and require replacement of the fish ladder
1114 structure at SW 23rd Street.
1115 Exhibits 7 and 8 summarize the potential permanent
1116 stream and wetland effects from the Master Plan
1117 Footprint (Exhibit 10) in the Panther/Springbrook
1118 Creek watersheds.
I
Exhibit 7. Potential Stream Effects From Master Plan Footprint
Permanent Effects'
Location of
Stream Effect DNR Type Below OHWM(SF) Stream Buffer(AC)
Rolling Hills Creek(09.SC-28) F 4,738 0.66
Unnamed Tributary to Rolling Hills Creek(09.RH-2.6) F 699 0.28
Thunder Hills Creek(09.RH-3.0) F 2,463 0.86
Unnamed Tributary to Thunder Hills Creek(Stream F 76 0.10
Tributary)
East Fork Panther Creek(09.SC-25.7) F 44,654 0.272
West Fork Panther Creek(09.SC-24.7) F 12,101 0.68
Total Effects 64,731 2.85
1.Permanent stream effects are approximate and based upon the Tukwila to Renton Ecosystems Discipline Report and potential Master
Plan effects for these locations.
2.To avoid double counting for impacts to stream and wetland buffers,additional effects to stream buffers are included in the Panther
Creek Wetland Buffer effects found in Exhibit 8.
SF=square feet;AC=Acres;DNR Stream type: F=not classified as shorelines of the state,but are natural waters that have fish,wildlife,or
human use
1-405 Water Resource Initiative at Panther Creek Wetlands
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PRELI1bIINARY DRAFT FOR MULTI-AGENCY PERMITTING TEAM(INAPT)REVIEW
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1119
Exhibit 8. Potential Wetland Effects From Master Plan Footprint
Permanent Effects'
Location of Wetland Effect Category' Wetland (AC) Wetland Buffer (AC)
Panther Creek Wetland II 4.87 4.32
(24.7R)
7
Wetland East of SR 167 111 0.61 3.27
(25.OL)
Total Effects 5.48 7.59
1.Permanent stream effects are approximate and based upon the Tukwila to Renton Ecosystems Discipline Report and potential
Master Plan effects for these locations.
2.Washington State Wetland Rating System for Western Washington—Revised(Hruby 2004)
AC=acres
1120
1121 What objectives are proposed to rehabilitate streams and fish habitat?
1122 The PCWRP proposes the following objectives for
1123 rehabilitating streams and fish habitat that address the
1124 watershed limiting factors and capitalize on site
1125 specific opportunities:
1126 Remove/improve barriers to fish passage at
1127 three locations including the SW 23rd Street
1128 fish ladder, Talbot Road, and Carr Road to
1129 improve watershed connectivity. This will open
1130 up to 3 miles of fish habitat for resident and
1131 juvenile salmonid species between the SW
1132 23rd Street fish ladder and Panther Lake.
1133 Provide salmonid refuge for juvenile Chinook
1134 and coho from Springbrook Creek to use the
1135 Panther Creek Wetlands for overwinter rearing
1136 in off-channel wetlands and Panther Creek.
1137 Juvenile coho will also utilize the same
1138 overwinter habitat for rearing and feeding.
1139 Adults that try to access and use upper
1140 Panther Creek for spawning would also
1141 benefit.24
1142 Provide functioning riparian habitat with in-
1143 channel habitat structure (LWD). Increase
1144 native plant diversity and remove and/or
1145 control invasive species.
24 Panther Creek Fish Passage Memorandum. LaRiviere.2006.
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 33
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1146 Improve degraded water quality by steepening
1147 channel's longitudinal gradient near the alluvial
1148 fan (topography permitting) to aerate flows for
1149 increased dissolved oxygen. Riparian shade
1150 plantings near channel to lower summer water
1151 temperatures.
1152 To achieve the above objectives, these actions will be
1153 implemented as shown in Exhibits 9 and 10:
1154 Stream Rehabilitation 1 (SR1)
1155 The PCWRP proposes several off-site and out-of-kind
1156 mitigation opportunities for effects to Rolling and
1157 Thunder Hills Creeks. This is consistent with the
1158 watershed level approach and based on the following
1159 three factors:
1160 The affected stream reaches in Rolling and
1161 Thunder Hills Creeks have poor, fragmented
1162 habitat.
1163 Rolling Hills Creek is piped for more than 2,000
1164 LF between SR 167 and Springbrook Creek
1165 (SW 19th Street).
1166 Prioritization of Master Plan mitigation dollars
1167 to address watershed limiting factors.
1168 1-405 road widening will affect Rolling Hills Creek and
1169 Thunder Hills Creek. Rolling Hills Creek will be
1170 affected in the vicinity of the SR 515 and SR 167
1171 Interchanges in the locations described in Exhibit 7.
1172 The affected reaches will be piped as a result of ROW
1173 limitations and fills and retaining walls necessary for
1174 road widening (Exhibit 9). WSDOT proposes off-site
1175 and out-of-kind mitigation for these effects with stream
1176 rehabilitation on Lower Springbrook Creek. This
1177 location has been identified by the City of Renton,
1178 U.S. Army Corps of Engineers (Corps) and the King
1179 County 2005 Green/Duwamish and Central Puget
1180 Sound Watershed Salmon Habitat Plan.25
1181
25 Green/Duwamish and Central Puget Sound Watershed Salmon Habitat Plan. Washington State Department of Fish
and Wildlife. August 2005.
I-405 Rater Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 34
PREI-1 NIINARY DRAFT FOR MULTI-AGENCY PERMITTING TEAM(MAPT)REVIEW
CONCEPT DEVELOPMENT
`y
tiR5 (
SR4 �3
SR3 FI1 t
Ih,
K -
i o
�I
+ Rentm Nhkel SVeam Mitigation - ` '.,�•`
m SpnngE•opk Geek ` T
.. I
4 r.
. rg
-""YbbMll�� Legend
Enhance 25 acres of stream buffer/PEM wetlands
FI1 dominated by reed canarygrass and create off-channel
Master Plan Footprint wetland fish habitat.
Enhance 7.5 acres of stream buffer/PF01 wetland.
Stream Relocation for SR 167 HOV Lane FI2 Plant native understory and conifers.Control/remove
reed canarygrass.
Proposed Trail
SR1 Rehabilitate 2,400 LF of lower Springbrook Creek
erpx abler ap�np s—n y� Stream(Open Channel) stream bank(approved by WRIA9).
tn•n Fn••g•Mma�ai ,s ,.t
a Stream(Piped) 0Construct Springbrook Trail(2,400 LF).
u 161 1 - SR2 Replace SW 23rd Street fish ladder to improve fish
Stream Rehabilitation passage.
-Associated Floodplain Improvements Relocate 5,350 LF of Panther Creek and provide
off-channel wetland fish habitat. Deepen channel
Other Watershed Rehabilitation cross section.
Efforts Not Part of This Plan
c e SR4 Replace Talbot Road South culvert to eliminate fish
passage barrier.
0 500
+—i SRS Carr Road culvert modifications and earthen/concrete
_... ... 1. Feet dam removal to eliminate barriers to fish passage.
1182 j
1183 Exhibit 9. Concept Plan
I-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan z:
PRELIMINARY DRAFT FOR MULTI-AGENCY PERMITTING TEAM(MAPT)REVIEW
CONCEPT DEVELOPMENT
1184
1185
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 36
PRELIMINARY DRAFT FOR MULTI-AGENCY PERMITTING TEAM(NIAPT)REVIEW
CONCEPT DEVELOPMENT
'.
t
SR4 a
� FH
(, Permanent
- `' SR3 F11 Diversion
167 ;! ya
- •y �i
SR2
e I
S
L�
Legend
Enhance 25 acres of stream buffer/PEM wetlands
FIt dominated by reed canarygrass and create off-channel
Master Plan Footprint wetland fish habitat.
Existing Contour(2 FT contour interval)
Enhance 7.5 acres of stream buffer/PF01 wetland.
- i, • •••• �� Stream(Open Channel) FI2 Plant native understory and conifers.Control/remove
• • •• reed canarygrass.
I •• • Stream(Piped)
—E Proposed Stream
SR1 streamlita bank(approved r blower IA9). brook Creek
^ c. Stream Relocation for SR 167 HOV Lane O Construct Springbrook Trail(2,400 LF).
!� SR1
Proposed Trail Replace SW 23rd Street fish ladder to improve fish
SR2 passage
-Stream Rehabilitation
_ Relocate 5,350 LF of Panther Creek and provide
-Associated Floodplain Improvements SR3 off-channel welland fish habitat. Deepen channel
cross section.
S ®Other Watershed Rehabilitation
`) Efforts Not Part of This Plan SR4 Replace Talbot Road South culvert to eliminate fish
•• • - - —:"1 Direct Discharge Areas passage barrier.0• - from Master Plan Footprint Cart Road culvert modifications and earthen/concrete
T tr 0 250 SR5 dam removal to eliminate barriers to fish passage.
Feet
1187 Exhibit 10. Concept Plan Enlargement
I-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 3-
PRELIMINARY DRAFT FOR MULTI-AGENCY PERMITTING TEAM(MAPT)REVIEW
CONCEPT DEVELOPMENT
1188
1189
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 38
PRELIMINARY DRAFT FOR Mu►.,r►-AGENCv PERM11►"CT►NG Team(MAPT)REv►ENN
CONCEPT DEVELOPMENT
1190 The Corps Green/Duwamish River Basin Ecosystem
1191 _ Restoration Study(Site No. 7) proposed conceptual
1192 -$ , ' ' ' design (Appendix C) for channel and habitat
1193 Y modifications in the area identified in the City of
1194 Renton's 1997 East Side Green River Watershed
1195 Project(ESGRWP). WSDOT proposes to use
1196 implement a 2,400 LF reach of Site No. 7 as an
1197 alternative watershed project to mitigate effects to the
1198 Rolling Hills and Thunder Hills creeks (See SR1,
1199 ;. Exhibit 9). The goal of the Corps plan for the Lower
1200 Springbrook Creek reach is to create a natural habitat
1201 for rearing and storm refuge that increases the
1202 hydraulic capacity of the channel.
1203 Lower Springbrook Creek at Creek Mile 1.0, Limiting factors identified in the ESGRWP indicate that
1204 Project LG-19 in the WRIA 9 Salmon the reach is lacking native riparian vegetation and
Habitat Plan g p g
1205 reed canarygrass and black berries leave the stream
1206 surface open to solar insulation. There is essentially
1207 no instream habitat such as woody debris.
1208 In response, habitat improvements would include
1209 plantings in the riparian corridor and placement of
1210 large woody debris in the creek. The Corps identified
1211 locations for one stage and two stage channels (see
1212 typical cross sections Appendix C). The proposed
1213 channel would have a higher cross sectional area than
1214 that of the existing channel to prevent a decrease in
1215 hydraulic capacity.28 This plan proposes to implement
1216 a portion, 2,400 LF (70,000 SF below OHWM) of the
1217 Corps plan downstream of SW 23rd Street. Stream
1218 rehabilitation will include the following (Appendix C):
1219 . Place LWD (2 pieces every 50 feet) and
1220 plantings in a re-channeled reach with minimal
1221 disturbance of the low flow channel.
1222 . Create in-channel pools. Excavating moderate
1223 pools for placement of wood will prevent it from
1224 decreasing the hydraulic capacity of the
1225 channel.
1226 . Excavate channel branch dendrites.
1227 . Create a 1-stage and 2-stage (low- and high-
1228 flow) channel (where appropriate).
1229 . Create hummocks (every quarter mile) with cut
1230 material from dendrite construction and re-
1231 channeling will limit off-site haul and promote
1232 geochemical functions.
28 U.S.Army Corps of Engineers. 2000.
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 39
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1233 This work will require environmental easements through
1234 various private properties. Any instream habitat
1235 improvements will require the permission of the King
1236 County drainage district No. 1, which owns a 40-foot
1237 width of ROW along the creek.
1238 Stream Rehabilitation 2 (SR2)
1239 The fish ladder at SW 23rd Street will be relocated
1240 due to the Master Plan footprint east of SR 167. This
1241 plan proposes replacement of the fish ladder with a
1242 structure that meets the 2003 WDFW guidelines for
1243 freeboard, fishway bends, and depth over the weirs for
1244 a fish passage target flow of 34 cfs (Appendix B).
1245 Stream Rehabilitation 3 (SR3)
1246 Approximately 44,654 SF (East Fork) and 12,101 SF
1247 (West Fork) of Panther Creek will be affected by fills
1248 and retaining walls necessary for road widening
1249 (Exhibit 10). To mitigate for these effects, this plan
1250 proposes to rehabilitate approximately 5,350 LF
1251 (85,000 SF below OHWM) of East Fork Panther Creek
1252 located in the PCW. Stream rehabilitation will include
1253 G � ��`� '` 'f ;'� the following:
1254 Relocate Panther Creek out of the confined
1255 roadside ditch and restore a riparian
1256 buffer/wetland/stream complex that provides
1257 - s "` the 115-foot stream buffer required by
1258 Washington State Department of Natural
1259 Resources (DNR) for a Type F stream. This
1260 ,n� "" single action will restore 12.81 AC of riparian
1261n ... . : y- - µ buffer between SR 167 and the west bank of
1262 ` Panther Creek to improve water quality and
1263 Panther Creek east fork at alluvial fan riparian habitat.
exhibits extensive braiding and
1264 sedimentation during storm events Create a natural meandering channel
1265 morphology that is hydraulically connected with
1266 the riverine wetland.
1267 Create a deeper channel cross section (+/-3
1268 feet below existing grade, channel width to be
1269 determined) to provide for fish passage as
1270 base flow. Steepen the channel's longitudinal
1271 gradient near the alluvial fan (topography
1272 permitting) to aerate flows, increase dissolved
1273 oxygen and improve water quality.
1274 Match the new stream longitudinal profile to
1275 critical existing elevations. The downstream
1276 end will meet and match the existing fish
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 40
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1277 ladder invert elevation to maintain current
1278 groundwater levels in wetland and bed control.
1279 Allow for sediment trapping within alluvial fan
1280 area.
1281 Provide a permanent diversion of Panther
1282 Creek flows to the south Panther Creek
1283 Wetland. This will provide a more reliable
1284 water source to the east fork stream channel in
1285 the south wetland to avoid periodic flow shifts
1286 and resulting impacts to stream and wetland
1287 hydrology that have occurred in the past.
1288 Avoid the 18-inch King County sewer line.
1289 • Connect new channel with the "SR 167 HOV
1290 Lane Project" (where feasible) (Exhibit 10).
1291 This would occur downstream of the flow split
1292 due to elevation constraints.
1293 . Excavate degraded palustrine emergent (PEM)
1294 Panther Creek west fork at inlet to SR 167 +/-2 feet to flood out reed canarygrass and
1295 culvert looking northward provide off-channel wetland juvenile fish
1296 rearing habitat in key locations (Exhibit 12).
1297 Fluvial geomorphology, wetland hydrology,
1298 sedimentation, and geotechnical analysis are key
1299 What is a hydroperiod? design processes that WSDOT will evaluate to
1300 A hydroperiod refers to the period of time a relocate the stream to the middle of the Panther Creek
1301 wetland is covered with water. Changes to wetland. Wetland hydrology is likely dependent upon
1302 how long a hydroperiod lasts can alter the a combination of groundwater, overbank flood flows
1303 types of plants and animals that a wetland from Panther Creek and seeps/drainages from Talbot
1304 supports. Hill. Changes to the wetland hydroperiod associated
1305 with stream channel excavation and permanent
1306 diversion will likely help to stabilize south wetland
1307 hydroperiod.
1308 Sediment deposition is occurring at an accelerated
1309 rate in the alluvial fan. Stabilization of eroding
1310 streambanks upstream of the wetland and on-site
1311 maintenance (sediment traps) would likely address
1312 this problem.
1313 Construction of a channel in the south wetland will be
1314 challenging due to the high groundwater table and
1315 dense layer of reed canarygrass (generally +/-12
1316 inches deep). Channel construction will be feasible if:
1317 . Work is done in the dry season and within the
1318 appropriate in-water work windows.
1319 • Low-ground-pressure tracked equipment is
1320 used in conjunction with steel plates or lie
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 41
PRELIMINARY'DRAFT FOR NIUL'Il-AGENCI PERMITTING TEAM(MAPT)REVIENN'
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1321 down mats, and/or a temporary hog-fuel type
1322 road for construction access into the wetland.29
1323 WSDOT will evaluate these design elements further
1324 as funding becomes available. Evaluation will include
1325 collection of groundwater data using wells and borings
1326 from geotechnical exploration that will further refine
1327 this plan.
1328 Stream Rehabilitation 4 (SR4)
1329 The Panther Creek/Talbot Road 120-foot-long, 3-foot-
1330 diameter culvert is a complete barrier to fish passage
1331 due to the outlet drop (+/-4 feet) combined with high
1332 velocities and low flow depths in the pipe30 (Appendix
1333 B). This fish barrier eliminates fish connectivity to the
1334 upper reaches of the watershed. The PCWRP
1335 proposes the following fish passage improvements to
1336 the Panther Creek/Talbot Road culvert (Exhibit 9) as
1337 off-site, out-of-kind mitigation for effects to Rolling Hills
1338 and Thunder Hills Creeks:
1339 Replace the culvert with a 5-foot-high by 18-
1340 foot-wide stream simulation box culvert.
1341 Install several upstream and downstream weirs
1342 to create a suitable gradient through the culvert
1343 for fish passage.
1344 Stream Rehabilitation 5 (SR5)
1345 The Panther Creek/SE Carr Road culvert is a barrier
1346 to upstream fish passage due to a 3-foot drop at the
1347 outlet and a series of irregular drops and cascades at
1348 the downstream end.31 The PCWRP proposes the
1349 following fish passage improvements to the Panther
1350 Creek/Carr Road culvert (Exhibit 9) as off-site, out of
1351 kind mitigation for effects to Rolling Hills and Thunder
1352 Hills Creeks:
1353 Install a series of weirs at the culvert outlet to
1354 step the channel up to the culvert.
1355 Replace 30 feet of culvert at downstream end.
1356 Retrofit existing portion of culvert with baffles.
1357 Remove earthen and concrete dam 120 feet
1358 upstream of Carr Road culvert. This would
29 WSDOT Panther Creek Wetlands Assessment. Jones&Stokes. October 19, 2005.
30 Fish Passage at Selected Panther Creek Culverts. RW Beck. February 24, 2006.
31 Fish Passage at Selected Panther Creek Culverts. RW Beck. February 24, 2006.
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 42
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1359 include reconstruction of 250 feet of natural
1360 channel at a gradient of about 6.5 percent and
1361 a step-pool channel configuration (Appendix B)
1362 to provide upstream fish passage.
1363 Stream rehabilitation summary
1364 As shown in Exhibit 11, the PCWRP provides 162,000
1365 SF (below OHWM) of stream rehabilitation.
1366
Exhibit 11. Summary of Proposed Stream Rehabilitation
Below OHWM Below OHWM Fish Barrier Stream Buffer
Location DNR Type (LF) (SF) Removal(LF) (AC)
SR1 (Springbrook S 2,400 70,000 4.40
Creek)
SR2(SW 23rd St. Fish F 800 75
Ladder)
SR3(Panther Creek) F 5,350 85,000
SR4(Panther Cr./Talbot S 1,200 120
Rd.Culvert)
SR5(Panther Cr.Carr F 5,000 425
Rd.Culvert)
Total Rehabilitation 7,750 LF 162,000 SF 620 LF 4.40 AC
Total Effects -- 64,731 SF -- 2.85 AC
Panther Creek stream buffer enhancements are shown in associated floodplain improvements,Exhibit 13.
OHWM=ordinary high water mark; LF=linear feet; AC=acres; SF=square feet
DNR Stream types: S=shorelines of the state; F=not classified as Type S,but are natural waters that have fish,wildlife,or human use
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 43
PRELIMINARI DRAFT FOR MULTI-AGENCY PERMITTING TEAM(MAPT)REVIEW
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1367 What objectives are proposed for associated floodplain
1368 improvements?
1369 North Wetland
1370 The North Wetland is characterized by a high quality
1371 palustrine forested and palustrine scrub-shrub
1372 (PF01/PSS1). WSDOT decided to not propose
1373 stream rehabilitation in this high quality wetland. In
1374 this area, the downstream fish barriers posed by the
1375 ; '' SW 19th Street pipe made off-site stream
1376 rehabilitation options elsewhere in the watershed a
1377 priority.
1378 South Wetland
1379 The south wetland is a combination of high quality PSS1
1380 (to the north) and PF01 (to the south) wetland vegetation
1381 communities that are separated by a large PEM
1382 community (Exhibit 3). The greatest opportunity for
1383 Ra } ! :; wetland enhancement in the PCW is in the south wetland
1384 because of invasive e.species
p (e.g., cattails and reed
1385 canarygrass) that predominate.
1386 The PCWRP proposes the following objectives for the
1387 Panther Creek South Wetland:
1388 a Increase native plant diversity.
1389 . Improve general habitat function.
1390 To achieve these objectives, the following actions will
1391 be implemented in locations shown in Exhibit 10:
1392 VVP2 is part of a palustrine scrub-shrub Floodplain Improvement Area 1 (FI1)
1393 wetland WSS11 with willow thickets Enhance +/-25 AC of floodplain that is PEM wetland
1394 and/or stream buffer as follows:
1395 Excavate (2 to 3 feet) to establish semi-
1396 permanently ponded deep PEM areas (where
1397 appropriate) for off-channel wetland fish habitat
1398 and to flood out reed canarygrass. Exhibit 12
1399 shows a typical cross section (A-A) through the
1400 south wetland.
1401 Improve wetland microtopographic complexity
1402 by mounding (+/-18 inches) along fringe PEM
1403 areas dominated by invasive species (e.g.,
1404 cattail and/or reed canarygrass) and planting
1405 with PFO/PSS vegetation (e.g., live willow
1406 stakes)for stream shading.
1407
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 44
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1408
1409 Exhibit 12. Typical Panther Creek Wetland Cross Section A-A
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 45
PREL►MINARI DRAFT FOR MELT►-AGENCY PERM►TT►NG TEAM(MAPT)REV►ENN
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1410 Install wetland habitat structures (e.g., snags,
1411 windthrow mounds, down logs, etc.).
1412 Floodplain Improvement Area 2 (FI2)
1413 . Enhance +/-7.5 AC of PF01 wetland
1414 community (Exhibit 10).
1415 . Remove and/or control invasive species in
1416 understory (e.g., Himalayan blackberry and
1417 reed canarygrass).
1418 . Infill mature PF01 wetland with native
1419 understory and evergreen tree plantings.
1420 Floodplain Improvements summary
1421 As shown in Exhibit 13, the PCWRP provides 32.5
1422 acres of floodplain improvements associated with
1423 stream rehabilitation in the south wetland.
1424
Exhibit 13. Summary of Associated Floodplain
Improvements
Ecologyand/or
Category'Location
F11 11 25.0
F12 11 7.5
Proposed Floodplain Improvement 32.5 AC
Total Permanent Wetland Effects 5.48
Total Wetland Buffer Effects 7.59
1.Washington State Wetland Rating System for Western Washington—Revised(Hruby 2004)
AC=acres
1425
1426 What is the Springbrook Creek Wetland Please note that floodplain improvements are
1427 and Habitat Mitigation Bank? necessary to provide for successful and self-
1428 The Springbrook Creek Wetland and Habitat sustaining stream rehabilitation in the PCW.
1429 Mitigation Bank are being developed as a PCWRP will not seek wetland mitigation for
1430 joint effort between WSDOT and the City of highway improvements with this plan because
1431 Renton. This `bank'will construct a new high WSDOT intends to provide wetland mitigation in
1432 quality wetland complex that will serve to this portion of the 1-405 Corridor by debiting credits
1433 replace other wetlands that are filled in by from the Springbrook Creek Wetland and Habitat
1434 projects such as the Renton Nickel Mitigation Bank.
Improvement Project. In addition to wetland
1435 mitigation, the site will also provide flood
storage mitigation.
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 46
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1436 What objectives are proposed for surface water?
1437 The PCWRP has several objectives for surface water
1438 management including:
1439 . Improve fish habitat, including stream flows;
1440 . Improve and/or preserve wetland functions and
1441 values;
1442 0 Reduce flooding downstream of the Panther
1443 Creek wetland complex;
1444 . Improve water quality;
1445 . Provide cost-effective freeway stormwater
1446 management that is compatible with the
1447 wetland and stream habitat.
1448 Strategy for stream flow management
1449 Each of the above objectives for surface water is
1450 discussed as they relate to a recommended strategy
1451 for stream flow management. Appendix C provides a
1452 summary of the hydraulic analyses and the technical
1453 memoranda that serve as the basis for this discussion.
1454 The strategy for stream flow management makes the
1455 following assumptions:
1456 ■ Panther Creek flows will be permanently
1457 diverted into the south Panther Creek wetland
1458 to provide adequate stream flow for fish
1459 habitat.
1460 ■ The above diversion will minimize flows out of
1461 SW 34th Street culvert and reduce
1462 downstream flooding.
1463 ■ More flow will be sent to the SW 19th Street
1464 drainage system, rather than the north Panther
1465 Creek wetland, while still meeting downstream
1466 flood control needs on the 19th Street system
1467 and Springbrook Creek.
1468 The 23rd Street outlet from the Panther Creek
1469 wetland will be slightly constricted when the
1470 fish ladder is replaced to compensate for the
1471 permanent diversion of Panther Creek into the
1472 south wetland and reduce downstream
1473 flooding.
1474 ■ The Renton Village storm system is already
1475 improved per City's plans to eliminate existing
1476 flooding.
1477 ■ The Master Plan Roadway footprint will be
1478 built.
1-405 Water Resource Initiative at Panther Creek Wetlands
Panther Creek Watershed Rehabilitation Conceptual Plan 47
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1479 A portion of the highway drainage will be
1480 directly discharged to Panther Creek wetland.
1481 Improve stream flows for fish habitat
1482 A characterization of the flows (nhc)30 for Panther
1483 Creek suggests that stream flows are limiting fish
1484 habitat when these flows are diverted to the SW 34th
1485 Street culvert by sedimentation in the alluvial fan.
1486 Exhibit 14 shows stream flows when the alluvial fan
1487 diverts flows to the SW 34th Street culvert. Also
1488 shown are stream flow predictions when stream flows
1489 are permanently diverted into the south Panther Creek
1490 wetland.
1491
Exhibit 14. Predicted Average Monthly Panther Creek Stream Flows Entering
the South Panther Creek Wetland for Current Conditions3' Compared to the
Recommended Flow Management Strategy
Flow statistic September November January April July
Existing Land Use and Most Panther Creek flows diverted into the south outlet along 34th street
Average flow 0.01 0.22 0.27 0.06 0.00
Low flow(10%) 0.00 0.00 0.00 0.00 0.00
Existing Land Use and Panther Creek flows are permanently diverted into the south Panther Creek wetland
Average flow 0.67 3.88 5.05 1.80 0.42
Low flow(10%) 0.24 1.40 2.02 0.74 0.25
1492
1493 From the information provided in Exhibit 14, we have
1494 concluded that a permanent diversion would be an
1495 important part of a preferred flow management
1496 strategy to improve fish habitat in the south Panther
1497 Creek wetland.
1498 Improve and/or Preserve Wetland Functions
1499 The PCW east of SR 167 is characterized by two
1500 distinct areas: a north forested wetland community and
1501 a south emergent wetland community that includes a
1502 mix of cattails and reed canarygrass. These areas are
1503 separated by a constructed berm (an Olympic gas
1504 pipeline corridor) near SW 23rd Street. Considering the
1505 higher quality forested wetland in the north, the strategy
30 Appendix C—Fish Passage Evaluation at Central Panther Creek Outlet. nhc. February 2006.
31 Assumes the alluvial fan in the Panther Creek wetland is diverting flows to the SW 34th Street culverts.
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1506 for stream flow management is to send more flow to the
1507 SW 19th Street drainage system while meeting
1508 downstream flood control objectives. As a result, this
1509 would reduce stream discharge into the north forested
1510 wetland community.
1511 The south Panther Creek wetland would receive more
1512 flow as a result of the stream flow strategy. The effects
1513 of this strategy on wetland hydrology were evaluated for
1514 changes in wetland water surface elevations and
1515 durations.
1516 A comparison of the stream flow strategy to baseline
1517 conditions for flows and wetland water surface
1518 elevations is provided in Exhibit 15.
1519 During high flood flows, the Panther Creek wetland
1520 water surface elevations vary from 0.2-foot to 0.8-foot
1521 increase, depending on which flood recurrence
1522 interval is considered (see Appendix C — page 5 and
1523 Table 6 in nhc December 2006). For lower, more
1524 frequent stream flows, the difference in wetland water
1525 surface elevations are less that 0.2 feet (see Table 7
1526 in nhc December 2006).
1527 The increase in wetland water surface elevations as a
1528 result of high flows will not occur for an extended
1529 period of time and the seasonal changes in wetland
1530 elevations are minimal (see page 5 and Table 27 in
1531 nhc December 2006).
1532
Exhibit 15. Predicted Surface Water Elevations in the Panther
Creek Wetland for Different Flood Flows for Baseline (Existing)
Conditions versus the Recommended Flow Management Strategy
y Panther Creek Water Surface Elevations
o, c
c o
2
X C • 1 • I • 11 year flow
W O
16.6 17.5 18.3 18.6
Panther Creek Water Surface Elevations
d
a T2 year flow 10 year flow 50 year flow 100 year flow
d
E 16.8 18.0 19.0 19.4
V N
Difference
7�07 0.5 0.7 0.8
Based on full build-out land use conditions—Data from Appendix C-nhc—December 2006—Table 6
I-405 Water Resource Initiative at Panther Creel:Wetlands
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I
1533
1534 Reduce flooding downstream of the Panther Creek
1535 wetland complex
1536 Specific locations were selected to evaluate the
1537 effects on flooding from the recommended flow
1538 management strategy. Some of the key areas
1539 included:
1540 ■ SW 23rd Street Channel
1541 ■ SW 19th Street Channel
1542 ■ SW 34th Street Drainage System
1543 ■ Springbrook Creek, downstream of confluence
1544 with SW 19th Street Channel
1545 For the SW 23rd Street Channel, a comparison of
1546 peak flows for the baseline (existing conditions) to the
1547 recommended flow management strategy (future
1548 condition) shows an increase in peak flows for more
1549 frequent floods (1/2 of the 2-year and 2-year) and a
1550 decrease in peak flows for less frequent floods (10-
1551 year, 50-year, and 100-year). This means
1552 implementation of the recommended flow
1553 management strategy would reduce peak flows and
1554 could help reduce backwater conditions in the 23rd
1555 Street channel which exacerbate flooding in the East
1556 Valley Road system (see Appendix C — pages 5 and 6
1557 in nhc December 2006).
1558 For the SW 34th Street drainage system, flooding is
1559 an existing problem (City of Renton 1997). During
1560 high flood conditions, Springbrook Creek actually
1561 backs water up into the SW 34th Street drainage
1562 system to cause flooding. Panther Creek flood flows,
1563 crossing SR 167 at the SW 34th Street culverts
1564 exacerbate this flood condition along East Valley
1565 Road. Implementation of the recommended flow
1566 management strategy would reduce higher flood flows
1567 (10-year, 50-year, and 100-year) at the south Panther
1568 Creek wetland outlet about 4-fold (see Appendix C —
1569 Table 6 in nhc December 2006).
1570 For Springbrook Creek downstream of the confluence
1571 with the SW 19th Street channel, the flow
1572 management strategy does not increase the peak
1573 flows (50-year and 100-year), even with the increase
1574 in flows down the SW 19th channel (see Appendix C—
1575 page 6 and Table 6 in nhc December 2006).
1576 Prior modeling (Appendix C) revealed flow increases
1577 attributed to coincident peak flows form the SW 19th
1578 Street system with peaks in Springbrook Creek.
1-405 Water Resource Initiative at Panther Creel:Wetlands
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1579 Under the recommended alternative, the slight
1580 constriction of the 23rd Street outlet from the Panther
1581 Creek wetland results in eliminating flow increases in
1582 Springbrook Creek (see Appendix C — page 6 and
1583 Table 6 in nhc December 2006).
1584 Effects on Water Quality
1585 Dissolved oxygen concentrations in Springbrook
1586 Creek are limiting to aquatic life. An opportunity exists
1587 to improve dissolved oxygen concentrations in
1588 Panther Creek as it flows through the south wetland at
1589 the location of the existing alluvial fan. This channel
1590 area will need to be modified to provide the permanent
1591 diversion of Panther Creek as part of the stream flow
1592 management strategy. WSDOT acknowledges the
1593 dynamic nature of the geomorphic conditions of the
1594 Panther Creek alluvial fan. This analysis indicates
1595 that any plan to provide habitat enhancements within
1596 in the south end of the Panther Creek wetland should
1597 incorporate improvements to ensure that Panther
1598 Creek continues to flow to this location. During
1599 channel design, providing fish passage to upstream
1600 areas will be a key objective. In addition, an effort will
1601 be made in channel design to create cascades to
1602 promote water aeration.
1603 The highway stormwater runoff from SR 167 and the
1604 1-405 interchange area will be treated with enhanced
1605 treatment prior to discharge to the Panther Creek
1606 wetland. The water quality of this discharge will be an
1607 improvement over existing conditions due to the
1608 improved treatment technology.
1609 Effects of a partial direct discharge of treated highway
1610 stormwater on wetland hydrology?
1611 WSDOT evaluated the engineering feasibility, wetland
1612 effects, and project cost savings of a direct discharge
1613 of treated highway stormwater to the south Panther
1614 Creek wetland. 1-405 team drainage engineers
1615 estimated that an area of about 28 acres of highway
1616 impervious surface could be routed and discharged,
1617 without detention, to the south Panther Creek wetland
1618 (see Exhibit 10). As noted above, this highway
1619 drainage discharge would receive enhanced water
1620 quality treatment but would not have flow control
1621 (detention). Nhc evaluated the effects of this
1622 discharge on the wetland hydrology of the Panther
1623 Creek wetland (nhc December 2006). Results
1624 showed that wetland hydrology in the Panther Creek
1625 wetland would not be impacted by the direct discharge
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1626 of this stormwater. Wetland water surface elevations
1627 would not be measurably affected by the direct
1628 discharge (see page 5, nhc, December 2006).
1629 The benefits of providing the directed discharge of
1630 treated stormwater include: 1) compliance with airport
1631 safety guidance, and 2) lower drainage costs. As
1632 previously mentioned, the Federal Aviation
1633 Administration has guidelines that restrict open water
1634 areas within a 10,000-foot boundary of the Renton
1635 Municipal Airfield because of safety concerning aircraft
1636 encountering birds. Open detention ponds within this
1637 area can be eliminated as a result of creating a direct
1638 discharge to the south Panther Creek wetland.
1639 How does this plan fit into the context of other watershed projects?
1640 Several other projects are planned that will contribute
1641 to overall watershed rehabilitation efforts (Exhibit 10),
1642 although not included in the PCWRP. Some of these
1643 are described below.
1644 Springbrook Creek Wetland and Habitat Mitigation
1645 Bank
1646 The Springbrook Creek Wetland and Habitat
1647 Mitigation Bank are being developed as a joint effort
1648 between WSDOT and the City of Renton. This
1649 mitigation bank is constructing a new high quality
1650 wetland complex that will replace other wetlands that
1651 are impacted by projects such as the 1-405: 1-5 to SR
1652 169 Widening Project. In addition to wetland
1653 mitigation, the site will also provide flood storage
1654 mitigation. The Springbrook Creek Wetland and
1655 Habitat Mitigation Bank is one of the first urban
1656 mitigation banks to be certified in Washington State.
1657 WSDOT West Fork Panther Creek Stream Mitigation
1658 for SR 167 HOV
1659 Upstream of SR 167 on the west fork of Panther
1660 Creek, 775 feet of stream channel will be relocated in
1661 association with the SR 167 HOV Lane Widening
1662 Project. The stream channel centerline will be
1663 relocated approximately 25 feet to the west of SR 167.
1664 The concept plan acknowledges this project and our
1665 plan's stream flow management strategy is to
1666 permanently divert Panther Creek flows to the south
1667 wetland. This would still leave the southern west
1668 branch tributary draining to the SW 34th Street culvert.
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1669 Renton Nickel Stream Mitigation on Springbrook Creek
1670 Also, the Springbrook Creek box culvert under 1-405
1671 will be removed and the streambed restored in that
1672 area as part of the construction of the new 1-405
1673 bridge that will span both Springbrook Creek and
1674 Oakesdale Avenue. These new bridge(s) are being
1675 constructed as part of the 1-5 to SR 169 Widening
1676 (formerly the 1-405 Renton Nickel Improvement
1677 Project). The new bridge(s) will replace the existing
1678 1-405 bridge over the Springbrook Creek side channel
1679 and Oakesdale Avenue.
1680 Upgrade Black River Pump Station (BRPS)
1681 WRIA 9 Salmon Habitat Plan identifies the BRPS for
1682 modification to improve fish passage. The existing
1683 fish passage system at the BRPS does not meet
1684 current national (NMFS) or state (WDFW) fish
1685 passage criteria. Harza (1995) recommended minor
1686 improvements to fish passage. More recently, HDR
1687 (2006) recommended major improvements, including
1688 construction of new pool and chute fish ladders, ladder
1689 height and fish screen adjustments and reduction or
1690 elimination of pipe transport to update the existing fish
1691 passage infrastructure to current design codes for
1692 juvenile upstream migration and adult downstream
1693 migration.
1694 King County issued a request for consultant proposals
1695 in 2006 and recalled the request after a short time.
1696 The current status of the implementation of upgrades
1697 to the Black River Pump Station is unknown at this
1698 time.
1699 WSDOT believes that modifications to the BRPS
1700 would complement other watershed rehabilitation
1701 strategies such as riparian restoration, small barrier
1702 removal, floodplain restoration, and water quality
1703 improvements.
1704 What are the benefits and costs of implementing this concept?
1705 Exhibit 16 provides a summary of how plan
1706 implementation addresses limiting factors for
1707 salmonids in the watershed.
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Panther Creek Watershed Rehabilitation Conceptual Plan 53
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CONCEPT DES ELOPD7ENT
1708
Exhibit 16. Benefits of the PCWRP as related to salmonid limiting factors in Panther
Creek/Springbrook Creek
salmonid Limiting Factors
Lack of Salmonid DegradedRiparian
Refuge Habitat
Establishes 0.50 AC Cascades to be provided in 7,750 LF(162,000 SF)of in- Removes 3
Benefits of the of off-channel new channel design(at channel improvements, barriers to fish
Panther Creek rearing habitat in alluvial fan)to provide water including 5,350 LF in Panther passage(620 LF)
Watershed Panther Creek aeration and improve Creek and 2,400 LF in within Panther
Rehabilitation Plan wetland dissolved oxygen Springbrook Creek Creek and
concentrations in Panther connects up to 3
Creek 36.9 acres of associated miles of Panther
floodplain improvements to Creek riparian
Riparian shade tree plantings stream buffer/wetlands habitat for fish use
to lower summer water including 12.8 acres of stream
temperatures buffer restoration to left bank of
east fork Panther Creek to
provide required buffer width
Enhanced water quality
treatment of WSDOT
stormwater discharged to the
Panther Creek wetland
complex
1709
1710
1711 The planning level cost to implement the watershed-
1712 How do project costs break out? level stream mitigation plan is approximately $13.9
1713 Stream Rehabilitation $5,075,000 million (See Break Out).
Floodplain Improvements $2,413,000
1714 The planning level cost (today's dollar) for highway
1715 Fish Passage Improvements $2,115,000 improvements in this area is $1.03 billion. The
1716 Springbrook Trail $906,000 stormwater management (quantity and quality) portion
Subtotal $10,509,000
1717 of these highway costs, using conventional practices,
1718 Sales Tax(8.80%) $925,000 is $46 million. The stormwater management cost
1719 Contingency(10%) $1,051,000 providing a direct discharge of treated stormwater, as
1720 PSE& Permitting (11%) $1,373,000 recommended in this PCWRP, is $29 million.
1721 Grand Total $13,858,000
1722 Costs are today's dollar and are approximate,based on
conceptual design.
1723 ROW costs are not included.It is assumed the City of
Renton will provide their Panther Creek wetland
1724 property for the project.
1725 What is the permitting strategy for this plan?
1726 WSDOT will partner with the City of Renton to obtain
1727 local permits and to work with the Multi-Agency
1728 Permitting Team (MAP Team) to obtain state and
1729 federal permits for the project. The MAP Team
1730 includes Washington State Department of Ecology,
1731 WDFW, WSDOT, U.S. Army Corps of Engineers, and
1732 King County Department of Development and
1-405 Water Resource Initiative at Panther Creek Wetlands
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1733 Environmental Services. Permits expected to be
1734 needed include: Section 404, National Pollution
1735 Discharge Elimination System, Section 401 Water
1736 Quality Certification, Coastal Zone Management
1737 Consistency Determination and Hydraulic Project
1738 Approval. Tribal consultation will occur during the
1739 NEPA/SEPA and permitting processes.
1740 WSDOT will work in a partnership with the City of
1741 Renton to ensure that the project complies with the
1742 City's Critical Areas Ordinances and obtains a
1743 Shoreline Substantial Development Permit for work
1744 near Springbrook Creek and a Public Works
1745 Construction Permit as needed. Also, any City
1746 easements within the project area will be reviewed.
1747 Early coordination with MAP Team, the City, U.S. Fish
1748 and Wildlife Service (USFWS), and NMFS will be
1749 critical in moving the project forward and providing the
1750 information necessary to obtain the required permits.
1751 The permit strategy is based on the following:
1752 Depending on funding and the needs of these
1753 transportation projects, WSDOT will develop
1754 the permitting strategy that is most appropriate
1755 for optimum and timely delivery of the road
1756 improvement projects.
1757 The rehabilitation sites currently owned by
1758 WSDOT are limited to the WSDOT ROW. The
1759 City of Renton owns or has easements for
1760 rehabilitation sites located within the Panther
1761 Creek wetland. None of the sites within the
1762 wetland are section 4(f) protected properties.
1763 Ownership of the remaining rehabilitation sites
1764 outside of this wetland complex is unknown at
1765 this time. It is also unknown if any of the
1766 rehabilitation sites are encumbered by land
1767 use restrictions that may preclude the
1768 proposed actions.
1769 Rehabilitation site SR1 is currently regulated
1770 by King County Drainage District No. 1
1771 (KCDD1). Rehabilitation site SR2 also may be
1772 regulated by KCDD1. Coordination with
1773 KCDD1 would occur before finalizing
1774 rehabilitation sites SR1 and SR2.
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1775 What are the next steps to move forward?
1776 A final AGREEMENT between the City of Renton and
1777 WSDOT for concept implementation will need to be
1778 reached. WSDOT ownership of the Concept sites is
1779 limited to WSDOT right-of-way. The City of Renton owns
1780 or has easements for areas located within the Panther
1781 Creek wetlands.
1782 Upon completion of the final AGREEMENT, Mitigation
1783 Report(s) in conformance with the WSDOT stream
1784 mitigation template (approximately 60 percent level of
1785 design) will be developed as standalone document(s) for
1786 the purpose of applying for permits. The Mitigation
1787 Report(s) will be identified as additional funding is
1788 obtained and include early coordination with MAP Team
1789 and the appropriate Tribes. At a minimum, the Mitigation
1790 Report will include contour grading plans and details,
1791 planting plans and details, construction and planting
1792 schedules and temporary erosion control plans and
1793 details. A site survey (including 1-foot contour
1794 information and location of areas of invasive species and
1795 individual significant trees) will be conducted. Additional
1796 information and studies required for the Mitigation Report
1797 may include:
1798 0 Refined hydrologic modeling informed by
1799 fluvial geomorphology analysis
1800 . Geotechnical data collection (borings) and
1801 channel design recommendations
1802 . Groundwater data collection (piezometers
1803 and/or wells)
1804 Sediment transport analysis featuring source
1805 and control/management recommendations
1806 The Mitigation Report will be submitted to the MAP
1807 Team to obtain the permits necessary for construction.
1808 The preparation of final construction documents would
1809 then follow as determined by 1-405 Corridor project
1810 needs.
1811
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REFERENCES
1812 REFERENCES
1813 Published Documents
1814 Anchor Environmental
1815 2006 Fish Habitat Memorandum. Prepared by Derek Koellmann.
1816 Harza
1817 1995 Final Report Comprehensive Fisheries Assessment of Mill Creek,
1818 Garrison Creek and Springbrook Creek System. Pgs. 99-104— Factors
1819 Limiting Salmon Production.
1820 HDR
1821 2006 Black River Pump Station Fish Passage Evaluation. January 2006.
1822 Hruby
1823 2004 Washington State Wetland Rating System for Western Washington —
1824 Revised.
1825 Jones & Stokes
1826 2005 WSDOT Panther Creek Wetlands Assessment. October 19, 2005.
1827 Kerwin, J.
1828 2001 Salmon and Steelhead Habitat Limiting Factors Report for the Cedar—
1829 Sammamish Basin (Water Resource Inventory Area 8), Washington
1830 Conservation Commission. Olympia, Washington.
1831 King County Department of Natural Resources (KCDNR)
1832 2000 Habitat Limiting Factors and Reconnaissance Assessment for Report
1833 Green/Duwamish and Central Puget Sound Watershed —Water Resource
1834 Inventory Area (WRIA) 9. Chapter 3.3 Springbrook Subbasin.
1835 2001 Distribution of Salmon and Trout Water Resource Inventory Area (WRIA)
1836 8 Lake Washington/Cedar/Sammamish Watershed [online] Available
1837 http://dnr.metrokc.gov/Wrias/8/fish-maps/distmap.htm, July 10, 2001.
1838 2005 Salmon Enhancement Plan: Making our Watershed Fit for a King—Green
1839 Duwamish and Central Puget Sound Watershed (WRIA) 9. Chapter 3.4 —
1840 Factors of Decline Specific to Subwatersheds.
1841 LaRiviere, Paul
1842 2006 Panther Creek Fish Passage Memorandum. January 12, 2006.
1843 National Oceanic Atmospheric Administration National Marine Fisheries Service (NMFS)
1844 1996 Habitat Publications & Related Guidance Documents —The Matrix Paper
1845 [Online] Available http://www.nwr.noaa.gov/Publications/Guidance-
1846 Documents/Habitat.cfm.
1847 northwest hydraulic consultants (nhc)
1848 2006 Panther Creek Watershed Rehabilitation Memo. Tukwila to Renton
1849 Improvement Project. December 22, 2006.
I-405 Water Resource Initiative at Panther Creek Wetlands
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REFERENCES
1850 2006 Fish Passage Evaluation at Central Panther Creek Outlet. February 17,
1851 2006.
1852 2005 Panther Creek Wetlands Supplemental Hydrologic December 23, 2005.
1853 2005 Part III of the South Renton Nickel Projects. May 19, 2005.
1854 RW Beck
1855 2006 Fish Passage at Selected Panther Creek Culverts. February 24, 2006.
1856 Renton, city of
1857 2005 SR 167 Alignment and Rainier Connection Recommendation. City of
1858 Renton Traffic Analysis Task Force. August 2005.
1859 1997 Eastside Green River Watershed Project Plan - Plan and Environmental
1860 Impact Statement. Prepared by RW Beck for the City of Renton.
1861 1992 Comprehensive Park, Recreation, and Open Space Plan. City of Renton.
1862 1991 City of Renton Trails Master Plan.
1863 U.S. Army Corps of Engineers (Corps)
1864 2000 Green/Duwamish River Basin Ecosystem Restoration Study. Final
1865 Feasibility Report. October 2000
1866 Washington State Department of Fish and Wildlife (WDFW)
1867 2005 Green/Duwamish and Central Puget Sound Watershed Salmon Habitat
1868 Plan. August 2005.
1869 2003 Design of Road Culverts for Fish Passage. May 2003.
1870 Washington State Department of Transportation (WSDOT)
1871 2006 Fish Passage at Evaluation at Central Panther Creek Outlet. Prepared by
1872 Matthew Gray.
1873 2006 Black River Pump Station Fish Passage Evaluation. January 2006.
1874 2005 1-405 Renton Nickel Improvement Project, 1-5 to SR 169. Wetlands
1875 Discipline Report. Prepared by Adolfson.
1876 2005 1-405 Renton Nickel Improvement Project, 1-5 to SR 169. Fisheries &
1877 Aquatic Resources Discipline Report. Prepared by Anchor
1878 Environmental.
1879 Wydosky, R.S. and R.R. Whitney
1880 1979 Inland fishes of Washington. University of Washington Press, Seattle,
1881 Washington.
1882 The Coot Company
1883 1989 P-9/Panther Creek Project Wetlands Inventory. June 29, 1989.
1884 The Watershed Company
1885 1989 Panther Creek Salmonid Fish Habitat Restoration May 10, 1989.
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REFERENCES
1886 Personal Communications
1887 Paul LaRiviere, HDR personal communication with Jon Gage on January 11, 2006.
1888
1889
I-405 Water Resource Initiative at Panther Creel:Wetlands
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REFERENCES
1890
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