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US Army Corps
Igo,} of Engineers
BIOLOGICAL ASSESSMENT
1161V
SPRINGBROOK CREEK WETLAND AND HABITAT MITIGATION BANK
January 2006
Urban Corridors
401 2nd Avenue South, Suite 560
Seattle, WA 98104-3850
Prepared by:
Washington State Department of Transportation
I-405 Project Team
Executive
22 EXECUTIVE SUMMARY
23 The Springbrook Creek Wetland and Habitat Mitigation Bank (Springbrook Bank) is a
24 Washington State Department of Transportation (WSDOT) and City of Renton partnership
25 project that will re-establish, rehabilitate, enhance, and preserve approximately 131.5 acres of
26 wetland, wetland buffer, and riparian and upland habitat areas on five parcels of land (Units A,
27 B, C, D, and E) located in Renton, Washington. The Springbrook Bank will provide
28 compensation for unavoidable impacts to wetlands and other aquatic resources resulting from
29 future WSDOT projects and additional development projects in the City of Renton that are
30 within the bank's service area. The service area of the Springbrook Bank includes portions of
31 select basins in the Lake Washington/Cedar/Sammamish (Water Resource Inventory Area
32 [WRIA] 8) Watershed and the Green/Duwamish and Central Puget Sound Watershed (WRIA 9)
33 including the lower Green River, Black River, West and East Lake Washington, May Creek, Mill
34 Creek, and Lower Cedar River to State Route 18 (SR 18) basins. Credits from the Springbrook
35 Bank may be used to compensate for impacts to category I, II, III, and IV wetlands (per
36 Washington State Department of Ecology [Ecology] definitions) within the service area.
37
38 Activities included in the development of the Springbrook Bank include re-establishing,
39 rehabilitating, and enhancing wetlands; establishing and enhancing upland and riparian buffer
40 areas; and constructing an interpretive trail system through Unit A. Wetlands will be re-
41 established on Units C and E by removing historic fill material. Improvements to the
42 hydrologic regimes of Units A, B, and C will lead to rehabilitation of the existing wetlands
43 located within those units. Existing wetlands in Unit C will be enhanced by increasing plant
44 and habitat diversity in areas dominated by invasive non-native vegetation, and in the northern
45 portion of Unit D by supplementing existing hydrology to extend existing hydrologic regimes.
46 Wetlands in all of the units will be further enhanced through installing habitat structures (e.g.,
47 large woody debris and vertical snags) and restoring native wetland plant communities. With
48 the exception of Unit D, each unit will include enhancements to upland and/or riparian habitat
49 areas and establishment of a 40-foot wide setback buffer that will be planted with native woody
50 plant species. In total, the Springbrook Bank will re-establish 17.81 acres of historic wetlands,
51 rehabilitate 52.92 acres and enhance 33.61 acres of existing wetlands, enhance 14.68 acres of
52 upland and riparian habitat areas, and enhance and protect an additional 9.86 acres of wetland
53 and upland habitat area by establishing the 40-foot-wide setback buffer.
Biological Assessment ES-1 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Executive
54 The Springbrook Bank is an Early Environmental Investment (EEI) project under the I-405
55 Congestion Relief and Bus Rapid Transit Projects and is being permitted in accordance with
56 WSDOT's Wetland Compensation Bank Memorandum of Agreement (CBMOA) (WSDOT 1994a), the
57 Federal Guidance for the Establishment, Use, and Operation of Mitigation Banks (USACE et al. 1995),
58 and negotiations with state and federal wetland regulatory agencies.
59
60 This Biological Assessment (BA) addresses impacts to Endangered Species Act (ESA) listed
61 species that may occur in the project's action area including: bald eagle (Haliaeetus leucocephalus),
62 the Coastal -Puget Sound bull trout (Salvelinus confluentus) Distinct Population Segment (DPS),
63 and the Puget Sound Chinook salmon (Oncorhynchus tshaunytscha) Evolutionarily Significant
64 Unit (ESU), all of which are listed as threatened under the ESA. It also addresses impacts to
65 Chinook salmon critical habitat and Essential Fish Habitat (EFH) within the project's action
66 area. Springbrook Creek is designated as critical habitat for Chinook salmon and is EFH for
67 Chinook and coho salmon. Springbrook Creek is not designated as bull trout critical habitat or
68 pink salmon EFH.
69
70 This BA does not address impacts to Canada lynx (Lynx canadensis), grizzly bear (Ursus arctos
71 horribilis), marbled murrelet (Brachyramphus marmoratus marmoratus), northern spotted owl
72 (Strix occidentalis caurina), or golden paintbrush (Castilleja levisecta) listed as threatened; marsh
73 sandwort (Arenaria paludicola) or gray wolf (Canis lupus) listed as endangered; or fisher (Martes
74 pennanti) a candidate species, as these species do not occur in the action area and because no
75 suitable habitat for these species occurs in the action area.
76
77 The effects determinations from the project on listed species and associated critical habitat are
78 as follows:
79
Biological Assessment ES-2 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
80
81
82
83
84
85
86
Executive Summary
Table ES-1
Threatened, Endangered, and Candidate Species That May Occur in the Project Area
Critical Habitat
Effects
Critical
Effects
Species
Status
Agency
Determination
Habitat
Determination
Puget Sound Chinook salmon
Threatened
NMFS
NLTAA
Designated
NLTAA
(Oncorhynchus tshawytscha)
(Puget Sound ESU)
Bull trout
Threatened
No bull trout
(Salvelinus confluentus)
(Coastal -Puget
USFWS
NLTAA
Designated
critical habitat in
Sound DPS)
the action area
Bald eagle
Threatened
USFWS
No Effect
None
N/A
(Haliaeetus leucoceohalus)
designated
LTAA = Likely to adversely affect
NLTAA = Not likely to adversely affect
ESU = Evolutionarily Significant Unit
DPS = Distinct Population Segment
NMFS = National Marine Fisheries Service
USFWS = U.S. Fish and Wildlife Service
It has also been determined that the project will have No Adverse Effect on Chinook or coho
salmon EFH.
Biological Assessment ES-3
Springbrook Creek Wetland and Habitat Mitigation Bank
January 2006
Table of Contents
87 EXECUTIVE SUMMARY.................................................................................................................... ES-1
88 1 INTRODUCTION................................................................................................................................1
89
2 PROPOSED PROJECT........................................................................................................................ 3
90
2.1 Project Setting.............................................................................................................................3
91
2.1.1 Unit A....................................................................................................................................
5
92
2.1.2 Unit B.....................................................................................................................................
7
93
2.1.3 Unit C.....................................................................................................................................
8
94
2.1.4 Unit D..................................................................................................................................10
95
2.1.5 Unit E...................................................................................................................................11
96
2.2 Springbrook Bank Project Description..................................................................................12
97
2.2.1 Wetland Re-Establishment...............................................................................................13
98
2.2.2 Wetland Rehabilitation.....................................................................................................13
99
2.2.3 Unit C Wetland Enhancement.........................................................................................14
100
2.2.4 Unit D Wetland Enhancement.........................................................................................14
101
2.2.5 Forested Wetland Enhancement......................................................................................14
102
2.2.6 Upland Habitat Enhancement.........................................................................................14
103
2.2.7 Riparian Upland and Upland Habitat Enhancement...................................................14
104
2.2.8 Protection Setback Buffer..................................................................................................15
105
2.2.9 Trail Zone............................................................................................................................15
106
2.3 Construction Activities............................................................................................................15
107
2.3.1 Site Preparation..................................................................................................................15
108
2.3.2 Excavation/Grading...........................................................................................................16
109
2.3.3 Planting...............................................................................................................................17
110
2.3.4 Weed Management............................................................................................................18
111
2.3.5 Staging Areas..........................................................................................................•...........19
112
2.3.6 Conservation Measures.....................................................................................................19
113
2.4 Project Schedule.......................................................................................................................
23
114
3 ENVIRONMENTAL BASELINE.....................................................................................................24
115
3.1 Action Area...............................................................................................................................
24
116
3.1.1 Action Area Description...................................................................................................
26
117
3.1.2 Noise Considerations........................................................................................................
26
118
3.2 Physical Indicators...................................................................................................................
27
119
3.2.1 Water Quality.....................................................................................................................
27
120
3.2.2 Habitat Access....................................................................................................................
28
121
3.2.3 Habitat Elements................................................................................................................
29
122
3.2.4 Channel Conditions and Dynamics................................................................................
30
123
3.2.5 Flow/Hydrology.................................................................................................................30
124
3.2.6 Watershed Conditions.......................................................................................................30
125
4 SPECIES OCCURRENCE, EFFECTS ANALYSIS, AND EFFECTS DETERMINATION ........
32
Biological Assessment i January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Table of Contents
126
4.1 Chinook Salmon.......................................................................................................................
32
127
4.1.1
Status...................................................................................................................................
32
128
4.1.2
Critical Habitat...................................................................................................................32
129
4.1.3
Biology and Distribution..................................................................................................
33
130
4.1.4
Direct and Indirect Effects................................................................................................
34
131
4.1.5
Effects Determination........................................................................................................
39
132
4.1.6
Critical Habitat Effects Determination............................................................................
39
133
4.2 Bull Trout..................................................................................................................................
40
134
4.2.1
Status...................................................................................................................................
40
135
4.2.2
Critical Habitat...................................................................................................................
40
136
4.2.3
Biology and Distribution..................................................................................................
40
137
4.2.4
Direct and Indirect Effects................................................................................................
41
138
4.2.5
Effects Determination........................................................................................................
45
139
4.2.6
Critical Habitat Effects Determination............................................................................
45
140
4.3 Bald Eagle..................................................................................................................................45
141
4.3.1
Status...................................................................................................................................
45
142
4.3.2
Critical Habitat...................................................................................................................45
143
4.3.3
Biology and Distribution..................................................................................................
45
144
4.3.4
Direct and Indirect Effects................................................................................................
47
145
4.3.5
Effects Determination........................................................................................................47
146 5 REFERENCES.................................................................................................................................... 48
147
148
149 List of Tables
150 Table ES-1 Threatened, Endangered, and Candidate Species That May Occur in the Project
151 Area.............................................................................................................................. ES-3
152 Table 1 Springbrook Bank Mitigation Restoration Activities and Acreage Summary ......13
153 Table 2 Springbrook Bank Plant Materials List.......................................................................18
154
155
156 List of Figures
157 Figure 1 Springbrook Creek Wetland and Habitat Mitigation Bank Springbrook Bank
158 Aerial Photo...................................................................................................................... 4
159 Figure 2 Springbrook Creek Wetland and Habitat Mitigation Bank Springbrook Bank
160 Action Area..................................................................................................................... 25
161
162
163 List of Photos
164 Photo 1 Looking west into Unit A from Lind Avenue SW Boulevard
165 Photo 2 Looking southward at Springbrook Creek flowing between Units A and B
166 Photo 3 Looking south into Unit B from SW 27th Street
Biological Assessment ii January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Table of Contents
167
Photo 4
Looking north into Unit C from the historic fill pad
168
Photo 5
Looking west into Unit C from the historic fill pad
169
Photo 6
Looking west into Unit D
170
Photo 7
Looking west from the central portion of Unit E
171
172
173
List of Appendices
174 Appendix A Springbrook Creek Wetland and Habitat Mitigation Bank Construction Plans
175 Appendix B Essential Fish Habitat Consultation
176 Appendix C Species Lists from NMFS and USFWS
177 Appendix D Fisheries Review White Paper
178
Biological Assessment iii January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Introduction
179 1 INTRODUCTION
180 The Springbrook Creek Wetland and Habitat Mitigation Bank (Springbrook Bank) is a
181 Washington State Department of Transportation (WSDOT) and City of Renton partnership
182 project that will re-establish, rehabilitate, enhance, and preserve approximately 131.5 acres of
183 wetland, wetland buffer, and riparian and upland habitat areas on five parcels of land (Units A,
184 B, C, D, and E) located in Renton, Washington. The Springbrook Bank will provide
185 compensation for unavoidable impacts to wetlands and other aquatic resources resulting from
186 future WSDOT projects and additional development projects in the City of Renton that are
187 within the bank's service area. The service area of the Springbrook Bank includes portions of
188 select basins in the Lake Washington/Cedar/Sammamish (Water Resource Inventory Area
189 [WRIA] 8) Watershed and the Green/Duwamish and Central Puget Sound Watershed (WRIA 9)
190 including the lower Green River, Black River, West and East Lake Washington, May Creek, Mill
191 Creek, and Lower Cedar River to State Route 18 (SR 18) basins. Credits from the Springbrook
192 Bank may be used to compensate for impacts to category 1, II, III, and IV wetlands (per
193 Washington State Department of Ecology [Ecology] definitions) within the service area.
194
195 Activities included in the development of the Springbrook Bank include re-establishing,
196 rehabilitating, and enhancing wetlands; establishing and enhancing upland and riparian buffer
197 areas; and constructing an interpretive trail system through Unit A. Wetlands will be re-
198 established on Units C and E by removing historic fill material. Improvements to the
199 hydrologic regimes of Units A, B, and C will lead to rehabilitation of the existing wetlands
200 located within those units. Existing wetlands in Unit C will be enhanced by increasing plant
201 and habitat diversity in areas dominated by invasive non-native vegetation, and in the northern
202 portion of Unit D by supplementing existing hydrology to extend existing and/or provide
203 additional hydrologic regimes. Wetlands on all of the units will be further enhanced through
204 installing habitat structures (e.g., large woody debris and vertical snags) and restoring native
205 wetland plant communities. With the exception of Unit D, each unit will include enhancements
206 to upland and/or riparian habitat areas and establishment of a 40-foot wide setback buffer that
207 will be planted with native woody plant species. In total, the Springbrook Bank will re-
208 establish 17.81 acres of historic wetlands, rehabilitate 52.92 acres and enhance 33.61 acres of
209 existing wetlands, enhance 14.68 acres of upland and riparian habitat areas, and enhance and
Biological Assessment 1 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Introduction
210 protect an additional 9.86 acres of wetland and upland habitat area by establishing the 40-foot-
211 wide setback buffer.
212
213 The Springbrook Bank is an Early Environmental Investment (EEI) project under the I-405
214 Congestion Relief and Bus Rapid Transit Projects and is being permitted in accordance with
215 WSDOT's Wetland Compensation Bank Memorandum of Agreement (CBMOA) (WSDOT 1994a), the
216 Federal Guidance for the Establishment, Use, and Operation of Mitigation Banks (USACE et al.1995),
217 and negotiations with state and federal wetland regulatory agencies.
218
219 This Biological Assessment (BA) addresses impacts to Endangered Species Act (ESA) listed
220 species that may occur in the project's action area including: bald eagle (Haliaeetus leucocephalus),
221 the Coastal -Puget Sound bull trout (Salvelinus confluentus) Distinct Population Segment (DPS),
222 and the Puget Sound Chinook salmon (Oncorhynchus tshawytscha) Evolutionarily Significant
223 Unit (ESU), all of which are listed as threatened under the ESA. It also addresses impacts to
224 Chinook salmon critical habitat and Essential Fish Habitat (EFH) within the project's action
225 area. Springbrook Creek is designated as critical habitat for Chinook salmon and is EFH for
226 Chinook and coho salmon. Springbrook Creek is not designated as bull trout critical habitat or
227 pink salmon EFH.
228
229 This BA does not address impacts to Canada lynx (Lynx canadensis), grizzly bear (Ursus arctos
230 horribilis), marbled murrelet (Brachyramphus marmoratus marmoratus), northern spotted owl
231 (Strix occidentalis caurina), or golden paintbrush (Castilleja levisecta) listed as threatened; marsh
232 sandwort (Arenaria paludicola) or gray wolf (Canis lupus) listed as endangered; or fisher (Martes
233 pennanti) a candidate species, as these species do not occur in the action area and because no
234 suitable habitat for these species occurs in the action area.
235
Biological Assessment 2 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
236 2 PROPOSED PROJECT
237 2.1 Project Setting
238 The Springbrook Bank site is located in the southwestern portion of the City of Renton,
239 Washington, Sections 25 and 36, Township 23N, Range 4E; and Section 30, Township 23N,
240 Range 5E. It consists of five units (Units A, B, C, D, and E), totaling 131.54 acres, which
241 represent some of the last remaining large tracts of undeveloped land in the Lower Green
242 River Basin. Eight large jurisdictional wetlands totaling approximately 89 acres exist on -site
243 and Springbrook Creek flows through portions of the site, bordering portions of Units A, B,
244 and E (WSDOT 2005a). Figure 1 is an aerial photo of the Springbrook Bank site.
Biological Assessment 3 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
248 Springbrook Creek is part of the Springbrook, Mill, and Garrison Creek Watershed (SMG
249 Watershed) located on the east side of the Green River. The SMG Watershed covers about
250 15,763 acres (24.6 square miles) and can be delineated into two distinct topographical areas:
251 the valley floor and the foothill zone. Slopes in the watershed range from 0 to 70 percent
252 and elevations range between 10 and 525 feet above mean sea level (Harza 1995).
253
254 Springbrook Creek is the SMG Watershed's main water conveyance channel, with its
255 tributaries, Mill and Garrison Creeks, coming in from the west (in the City of Kent), and
256 Panther and Rolling Hills Creeks, originating on plateaus east of the Green River Valley.
257 The lower reaches of Springbrook Creek have been historically straightened, deepened, and
258 widened by farmers, local jurisdictions, the Natural Resources Conservation Service
259 (NRCS), and King County Drainage District No. 1 to accommodate past agricultural
260 practices, and they continue to be managed for flood control purposes (Kerwin and Nelson
261 2000). Springbrook Creek ultimately flows into the Black River via the Black River Pump
262 Station (BRPS). The BRPS and associated infrastructure prevents high flows in the Green
263 River from backing water up into Springbrook Creek, reducing the risk of flooding in
264 adjacent areas.
265
266 Further information about each of the five units that comprise the Springbrook Bank is
267 provided below.
268
269 2. 1. 1 Unit A
270 Unit A encompasses 26.33 acres and is located between SW 27th Street, and SW 34th
271 Street, west of Lind Avenue and east of Springbrook Creek. The site is bordered along
272 its northern and eastern sides by arterials serving industrial activities and on the west by
273 Springbrook Creek and Unit B. The southern boundary is an undeveloped road right-
274 of -way adjacent to developed industrial zoned property.
275
276 Springbrook Creek flows within a straight, bermed corridor between Units A and B.
277 Precipitation and stormwater inputs from adjacent roads and development are the
278 primary sources of hydrology to the site, along with elevated groundwater during
279 wetter portions of the year. A ditch along the southern property line in Unit A collects
280 stormwater from the development to the south, ponded water from precipitation, and
Biological Assessment 5 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
281 seasonally elevated groundwater, and directs flows to Springbrook Creek. The berms
282 along Springbrook Creek prohibit the creek from accessing this unit except during
283 extreme flood events.
284
285 Vegetation found in Unit A varies depending on its proximity to Springbrook Creek.
286 Areas closest to the creek have substantial native woody cover consisting primarily of
287 Pacific willow (Saiix lucida), Sitka willow (Salix sitchensis), some black cottonwood
288 (Populus balsamifera), and red alder (Alnus rubra). Areas farther from Springbrook Creek
289 are dominated by reed canarygrass (Phalaris arundinacea) and cattail (Typha latifolia and
290 Typha angustifolia) with patchy woody cover provided by willow species. Reed
291 canarygrass dominates the riparian area on the berm directly adjacent to Springbrook
292 Creek.
293
294 Photo 1 shows Unit A as seen from Lind Avenue SW and Photo 2 shows Springbrook
295 Creek flowing between the earthen berms that separate Units A and B from Springbrook
296 Creek.
297
298
299
300
301
Photo 1
Looking west into Unit A from Lind Avenue SW
Biological Assessment 6 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
302
303
304
305
306
Photo 2
Looking southward at Springbrook Creek flowing between
Units A and B
307 2. 1.2 Unit B
308 Unit B encompasses 36.49 acres and is located immediately south of SW 27th Street, west
309 of and adjacent to Springbrook Creek, and east of Oakesdale Avenue SW. The site is
310 bordered on both the north and south by industrial development and on the east by Unit
311 A.
312
313 As with Unit A, precipitation and stormwater inputs from adjacent roads and
314 development along with elevated groundwater during wetter portions of the year are
315 the primary sources of hydrology to Unit B. A small ditch in the eastern portion of Unit
316 B is the only existing connection between Unit B and Springbrook Creek. Also as with
317 Unit A, the berms along Springbrook Creek prohibit the creek from accessing this unit
318 except during extreme flood events.
319
320 Vegetation found in Unit B varies depending on its proximity to Springbrook Creek.
321 Areas closest to the creek have substantial native woody cover consisting primarily of
322 Pacific and Sitka willow, some black cottonwood, and red alder. Areas farther from
323 Springbrook Creek are dominated by reed canarygrass, water pepper (Polygonum
324 hydropiperoides var. hydropiperoides), and cattail with patchy woody cover provided by
Biological Assessment 7 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
325 willow species. Reed canarygrass dominates the riparian area on the berm directly
326 adjacent to Springbrook Creek. Photo 3 shows Unit B as seen from SW 27th Street.
327
328
329
330
331
332
Photo 3
Looking south into Unit B from SW 27th Street
2.1.3 Unit C
333 Unit C encompasses 47.90 acres and is located east of the Burlington Northern Santa Fe
334 (BNSF) Railroad and west of Oakesdale Avenue SW. The site is bordered to the north
335 by undeveloped land and to the south by both an industrial railroad facility and
336 undeveloped land. The entirety of Unit C was once comprised of wetlands; however a
337 portion of this unit was historically filled with up to 7 feet of fill material.
338
339 Existing hydrology in Unit C is provided by a combination of precipitation and a
340 seasonally high groundwater table.
341
342 The wetland re-establishment area of Unit C is comprised predominantly of non-native
343 grasses, common tansy (Tanacetum vulgare), and Himalayan blackberry (Rubus
344 armeniacus). Existing wetlands and uplands at the site are dominated by black
345 cottonwood, red alder, Pacific willow, Sitka willow, and red -osier dogwood (Cornus
346 sericea) intermixed with Himalayan blackberry. The portion of the site closest to the
347 BNSF right-of-way consists of a matrix of large areas of reed canarygrass and patchy
Biological Assessment 8 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
348 native shrub cover along with patches of Himalayan blackberry. Along the eastern edge
349 of the site adjacent to Oakesdale Avenue, common tansy, lance -leaf plantain (Plantago
350 lanceolata), teasel (Dipsacus sylvestris), bull thistle (Cirsium vulgare), Himalayan
351 blackberry, and other disturbance -tolerant grasses and forbs are predominant.
352
353 Photos 4 and 5 were taken from a historic fill pad located within the southeastern corner
354 of Unit C, and show northerly and westerly views into Unit C.
355
356
357
358
359
Photo 4
Looking north into Unit C from the historic fill pad
Biological Assessment 9 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
360
361
362
363
Photo 5
Looking west into Unit C from the historic fill pad
364 2. >.4 Unit D
365 Unit D encompasses 5.60 acres and is located immediately north of an existing
366 stormwater treatment/detention pond constructed by the City of Tukwila for the 180th
367 Street grade -separation project.
.:
369 On the northern portion of Unit D, a shallow inundated area exists that appears to be
370 supported by precipitation, seasonal groundwater, and a surface water connection (via a
371 culvert) from wetlands located west of the BNSF mainline. Unit D discharges to the
372 north via a culvert under an existing BNSF rail line and an existing conveyance ditch to
373 Unit C.
374
375 The forested canopy of Unit D is comprised of red alder, black cottonwood, Pacific
376 willow, and Oregon ash (Fraxinus latifolia). The shrub layer includes salmonberry (Rubus
377 spectablis), red -osier dogwood, and hardhack (Spirea douglasii). Vegetation in the
378 inundated area at the northern end of the site consists primarily of cattails, reed
379 canarygrass, and mild water pepper. A few patches of Himalayan blackberry and reed
380 canarygrass occur in the forested portion of the existing wetland.
381
Biological Assessment 10 January 2006
Sgringbrook Creek Wetland and Habitat Mitigation Bank
382
Proposed Project
Photo 6 shows Unit D as seen from the industrial property located immediately east of
383 this unit.
384
385
386
387
388
Photo 6
Looking west into Unit D
389 2.1.5 Unit E
390 Unit E encompasses 15.22 acres and is located south of SW 34th Street, west of
391 Springbrook Creek, north of SW 41st Street, and east of Oakesdale Avenue SW. It is
392 bordered to the north by developed light industrial properties.
393
394 No wetlands currently exist on Unit E. The entirety of Unit E was once comprised of
395 floodplain wetlands; however, this unit was historically filled with approximately 10 to
396 15 feet of fill material.
397
398 Large portions of Unit E have been impacted by off -road vehicle use. In these areas,
399 vegetation is dominated by non-native grasses, common tansy, and Himalayan
400 blackberry. The remainder of Unit E is dominated by black cottonwood forest with an
401 understory comprised primarily of Himalayan blackberry.
402
403 Photo 7 was taken near the center of Unit E and shows a westerly view into this unit.
404
Biological Assessment 11 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
405
406
407
408
Photo 7
Looking west from the central portion of Unit E
Project
409 2.2 Springbrook Bank Project Description
410 The Springbrook Bank will re-establish, rehabilitate, enhance, and preserve approximately
411 131.5 acres of wetland, wetland buffer, and riparian and upland habitat areas on five parcels
412 of land (Units A, B, C, D, and E). In total, the Springbrook Bank will re-establish 17.81 acres
413 of historic wetlands, rehabilitate 52.92 acres of existing wetlands, enhance 33.61 acres of
414 wetland, enhance 14.68 acres of upland and riparian habitat areas, and enhance and protect
415 an additional 9.86 acres of wetland and upland habitat area by establishing the 40-foot wide
416 setback buffer. The restoration activities to occur on each unit are detailed in Table 1. In
417 addition to these restoration activities, the Springbrook Bank includes the development of a
418 new public boardwalk trail through Unit A.
419
Biological Assessment 12 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
Table 1
Springbrook Bank Mitigation Restoration Activities and Acreage Summary
Restoration Activity
Unit A
Unit B
Acreage
Unit C Unit D
-_.
Unit E
Total
Wetland Re -Establishment
0.05
0.12
9.70
-
8.37
17.81
Wetland Rehabilitation
= 20.30
31.43
1.19
_......
-
--....._......_-._..._..._-..._...
-
52.92
- -
-- -- -- --
Unit CWetland Enhancement
t
-
-
4.69
-
-
4.69
Unit D Wetland Enhancement
-
-
-
2.63
-
2.63
Forested Wetland Enhancement
-
-
23.32
2.97
-
26.29
Riparian Upland Enhancement
1 0.65
1.49
-
-
4.74
6.88
Upland Habitat Enhancement
-- ---... _......................................... _.._._... ............
-
-
__
7.80
_...__..
-
.....-._.._.._. ...-._..._....--
- ....__..
7.80
Protection Setback Buffer
2.67
3.45
1.63
-
"
2.11
9.86
Trail Zone
# 2.66
_......_......_........._--
.........
. ..........
-
2.86
Totals
26.33
36A9
j 47.90
G 5.60 !
15.22
131.64
Specific restoration activities to occur on Units A, B, C, D, and E are described in greater
detail below.
2.2. 1 Wetland Re -Establishment
Wetland re-establishment will primarily occur on Units C and E. Fill material will be
removed to allow ground and surface waters to restore hydrology to the historic
wetlands located in these units. After the fill material is removed, portions of an existing
earthen berm separating Unit E from Springbrook Creek will be breached to allow
Springbrook Creek to reconnect to its newly reclaimed historic floodplain. Native -
woody plant species will be installed in both units to increase plant species diversity.
Habitat structures (e.g. vertical snags, brush piles, and/or anchored logs) will be
installed to increase habitat diversity and complexity.
2.2.2 Wetland Rehabilitation
Wetland rehabilitation will occur in Units A, B, and C. The historic connection between
the floodplain wetlands in Units A and B and Springbrook Creek will be re-established
and additional water will be provided to the existing wetlands in Unit C. This will
improve the hydrologic regime and facilitate the rehabilitation of existing wetlands in
each of these units. Planting hummocks (a low mound or ridge of earth located in a
wetland area used to help establish upland or transitional zone plant species) will be
Biological Assessment 13
Springbrook Creek Wetland and Habitat Mitigation Bank
January 2006
Proposed Project
444 installed to provide additional habitat niches, enhance hydrologic regimes, and facilitate
445 conifer and deciduous tree establishment. Native woody plant species and habitat
446 structures will be installed in Units A, B, and C.
447
448 2.2.3 Unit C Wetland Enhancement
449 Existing wetlands in Unit C will be enhanced by treating and controlling invasive non-
450 native vegetation (reed canarygrass and Himalayan blackberry), and increasing plant
451 diversity and habitat complexity. This will be accomplished by implementing reed
452 canarygrass and Himalayan blackberry control measures, densely planting native trees
453 and shrubs, installing habitat structures, and establishing planting hummocks in reed
454 canarygrass removal areas.
455
456 2.2.4 Unit D Wetland Enhancement
457 Supplemental hydrology will be provided to existing seasonally inundated areas in the
458 northern portion of Unit D. Water will be diverted from an existing stormwater
459 treatment/detention pond outfall pipe at the southern end of Unit D and transported to
460 the northern end of Unit D via a new conveyance pipe. The additional hydrology will
461 extend the existing hydroperiod and/or provide additional hydrologic regimes to Unit
462 D. This additional surface hydrology will also benefit Unit C since surface hydrology
463 from Unit D drains northward to Unit C via an existing conveyance ditch.
464
465 2.2.5 Forested Wetland Enhancement
466 Wetland -tolerant, native conifer species will be underplanted in the existing deciduous
467 forested wetland portions of Units C and D.
468
469 2.2.6 Upland Habitat Enhancement
470 Invasive plant species will be removed and habitat structures installed to enhance
471 upland habitat in Unit C. In addition, Unit C will be densely planted with native -woody
472 plant species.
473
474 2.2.7 Riparian Upland and Upland Habitat Enhancement
475 Native riparian vegetation will be re-established on Units A, B, and E through a
476 combination of mechanical and chemical treatment of reed canarygrass and Himalayan
Biological Assessment 14 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
477 blackberry, and planting of native -woody plant species. In addition, habitat structures
478 will be placed in portions of Unit E.
479
480 2.2.8 Protection Setback Buffer
481 Forty -foot -wide protection setback buffers will be established on portions of all of the
482 units, except for Unit D. These wetland and upland buffers will be planted with native-
483 woody plant species to promote structural diversity and protect habitat from
484 disturbance from adjacent land uses.
485
486 2.2.9 Trail Zone
487 An elevated, 8-foot wide and average 3-foot high public boardwalk trail will be
488 constructed across the western edge of Unit A, roughly parallel to Springbrook Creek.
489 Use of the trail will be limited to pedestrian foot traffic only. A 40-foot-wide vegetated
490 buffer will be installed on each side of the trail (the vegetated buffer acreage is detailed
491 as a trail zone in Table 1). The elevated boardwalk will connect to local and regional trail
492 systems including King County's regional Interurban and Green River Trails. Benches
493 will be placed at two locations along the trail to facilitate passive recreation, such as bird
494 watching. In addition, interpretive signs will describe the unique natural features and
495 environmental benefits of the Springbrook Bank.
496
497 2.3 Construction Activities
498 2.3. f Site Preparation
499 Initially, high visibility fencing will be installed around the perimeter of the site and
500 around the perimeter of all proposed work areas to prevent equipment intrusion into
501 areas where no work is proposed. In addition, silt fencing will be installed along the
502 entire length of Springbrook Creek and a compost berm along the perimeter of all
503 proposed clearing, grubbing, and grading areas to prevent turbid water from entering
504 Springbrook Creek and adjacent areas where no work is proposed. Temporary
505 construction entrances and fire wash areas will be installed on each unit. The
506 construction entrances will be constructed using geotextile fabric topped with 4- to 8-
507 inch quarry spalls. The tire wash water will be discharged to a Baker tank and then
508 either hauled off or discharged into a sanitary sewer. The exact method of removal will
509 be determined by the contractor.
Biological Assessment 15 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
510 2.3.2 Excavation/Grading
511 Site grading and excavation related to the project consists of excavating large areas of
512 Units C and E to re-establish historic wetlands, installing earthen ditch plugs in the
513 existing conveyance ditch in Unit C, installing a stormwater pipe to supplement
514 hydrology in Unit D, and breaching the berms in Units A, B, and E to re-establish the
515 historic floodplain connection between these units and Springbrook Creek.
516
517 Approximately 100,000 cubic yards of fill from Unit C and 162,000 cubic yards of fill
518 from Unit E will be excavated from areas that were formerly wetlands. Excavation
519 depths in Unit C will range from a few inches to 7 feet, and in Unit E from a few inches
520 to approximately 12 feet depending on the location within each unit. Once the
521 excavation is completed, these units will be rough graded to provide microtopographic
522 variation (minor elevation changes throughout the graded area).
523
524 An existing conveyance ditch located on Unit C will be plugged with clean fill material
525 at regular spatial intervals so that it no longer conveys water flow. The height of the
526 ditch plugs will match the surface elevations on either side of the existing ditch.
527 Plugging the existing conveyance ditch will result in additional hydrology to the newly
528 created wetland on Unit C.
529
530 The existing earthen berms along Springbrook Creek will be breached along Unit A in
531 three locations, Unit B in four locations, and Unit E in three locations to reconnect
532 Springbrook Creek with its historic floodplain. The breaches on Units A and B will
533 measure 20 feet wide and approximately 2 to 3 feet deep to match the ground elevation
534 of the adjacent wetland surface. In Unit E, the breaches will range in measurement from
535 20 feet wide to nearly 100 feet wide and approximately 12 feet deep to a ground
536 elevation of approximately 8 feet. The berms will not be breached until the grading and
537 excavation within each unit landward of the berms is completed. Breaching of the
538 berms will occur during summer low flows so that no in -water work will be required in
539 Springbrook Creek. At Units A and B disturbed soil areas near Springbrook Creek will
540 be protected with coir or jute fabric and, at Unit E, quarry spalls interspersed with
541 plantings will be used to prevent erosion. The quarry spalls at Unit E will be located
542 approximately 5 feet from the toe of the slope and located up the slope a minimum of 3
Biological Assessment 16 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
543 feet, be incorporated into the ground surface, and will cover 754 square yards of the
544 surface of the breached berm.
545
546 Site work related to the project will be performed with standard construction equipment
547 including, but not limited to, track excavators, bulldozers, backhoes, and dump trucks.
548 All excavated material will be removed from the site and disposed at a WSDOT-
549 approved upland site.
550
551 Site grading and excavation work is detailed on the grading plans in Appendix A:
552 Springbrook Creek Wetland and Habitat Mitigation Bank Construction Plans.
553
554 2.3.3 Planting
555 Native vegetation will be planted on all of the units to increase the number and variety
556 of vegetation communities in the Springbrook Bank. Plant species were selected that are
557 known to occur naturally in the project area, will provide cover for wildlife, are tolerant
558 to flooding conditions, and have a high likelihood of success. Table 2 is a list of plants
559 that will be planted at the Springbrook Bank.
560
Biological Assessment 17 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
561 Table 2
562 Springbrook Bank Plant Materials List
563
Wetland Forest/Shrub #1 wetter
Riparian Upland Plantings
Oregon ash (Fraxinus latifolia)
— — Big -leaf maple (Acermacrophyllum)
—. — _.- __ .... ......
Black twinbery (Lonicera involucrata)
_ _ Red alder (Alms rubra)
Pacific ninebark (Physocarpus capitatus)
Sft ka spruce (Picea sdchensrs)
Black Cottonwood (Populus ba/samifera)
_ _ _ Douglas fir (Pseudotsuga menziesig
Nootka rose (Rosa nutkana)
scouleriana)
Sitka willow Salix sitchensis
Snowbe Sym hodca us albus
Wetland Forest/Shrub #2 wettest
Upland Habitat Planting
Red -osier dogwood (Comus sericea)
_. Big leaf mVle_(Acermacrophyllum)
Oregon ash (Fraxinus latifolia)
Serviceberry (Ame/anchier alnifolia1
— -- — - — _ ....
Peafruit wild rose (Rosa pisocarpa)
_ _ _ _ Beaked Hazel (Coryulus comuta)
Pacific willow (Salix /ucida)
Ocean_ps ray jHokodiscus discolor)
Sitka willow (Salix sitchensis)
_ — _ Douglas fir (Pseudotsuga menziesr�
Snowbe S m honca us albus
Wetland Forest/Shrub #3 wet
Hummock Plantings
Sitka spruce (Picea sdchensis)
_ _Oregon ash (Frax�nus latrfolia)
Black Cottonwood (Populus balsamifera)
_ Pacificninebark (Physocarpus capitatu�
Nootka rose (Rosa nutkana)
Scoulers willow (Salix scoulenana)
Western red cedar hu a licata
Western red cedar hu a licata
Wetland Forest Under -Planting
Sitka spruce (Picea sitchensis)
Western red cedar (Thuja plicata)
Western hemlock su a hete h lla
564
565 Planting plans for the Springbrook Bank are detailed in Appendix A: Springbrook Creek
566 Wetland and Habitat Mitigation Bank Construction Plans.
567
568 2.3.4 Weed Management
569 Weeds will be managed at Springbrook Bank in accordance with King County Noxious
570 Weed Law and the Washington State Noxious Weed List, with additional focus on
571 reducing existing reed canarygrass and Himalayan blackberry, and limiting additional
572 reed canarygrass and Himalayan blackberry establishment. Reducing existing reed
573 canarygrass and limiting additional reed canarygrass establishment will be
574 accomplished through a strategy of increasing the overall amount of large woody plant
575 materials within the Springbrook Bank to shade out reed canarygrass over the long
576 term. This strategy initially involves mowing and spraying to suppress the existing reed
577 canarygrass colonies in Units A, B, C, and E.
578
579 Mowing will occur in June or July before reed canarygrass seeds are formed. Spraying
580 (e.g. glyphosate [Rodeo ft will be conducted in August and again in September while
581 carbohydrates are being translocated from the aboveground parts to the roots.
Biological Assessment 18 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
582 Herbicides will be applied in accordance with the herbicide label, by a licensed
583 applicator with an aquatic endorsement. This will provide the best possible control of
584 below ground roots and rhizomes (Antieau 1998; Tu 2004; Reinhardt and Galatowitsch
585 2004). This approach minimizes soil disturbance that would expose the existing reed
586 canarygrass seed bank to light and trigger seed germination.
587
588 Long-term control of reed canarygrass at all the units will involve densely planting
589 native trees and shrubs, and "spot -spraying" reed canarygrass colonies during the
590 monitoring period to ensure long-term success in establishing the desired native woody
591 plant community.
592
593 2.3.5 Staging Areas
594 Units C and E will be used as staging areas prior to being excavated. In addition, the
595 existing roadbed within Unit D will also be used as a staging area for the project.
596 Additional off -site staging areas may be necessary to complete the project; however, the
597 locations of these additional off -site staging areas have not been determined. Any off-
598 site staging area locations will ultimately be determined by the project contractor;
599 however, WSDOT will require the contractor to locate any additional off -site staging
600 areas more than 300 feet from any wetlands, ditches, or flowing or standing water.
601
602 2,3.6 Conservation Measures
603 Conservation measures will be employed to minimize impacts to threatened and
604 endangered species from the project. Specifically, the following conservation measures
605 will be implemented:
606
607 2.3.6.1 Environmental Compliance
608 WSDOT will utilize a commitment tracking system to identify all
609 commitments made during ESA consultation, State Environmental Policy Act
610 (SEPA), design, and permitting. All project commitments will be clearly
611 communicated in the Special Provisions to the contractor, who will in turn
612 communicate commitments to project office staff and supporting design
613 offices. Commitments will be tracked throughout the various stages of the
614 project delivery.
Biological Assessment 19 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
615 A Spill Prevention, Control, and Countermeasures (SPCC) Plan for the
616 project, will be prepared and submitted by the contractor to the project
617 engineer prior to commencing any construction.
618
619 2.3.6.2 Erosion Control
620 • Impacts to wetlands and streams will be minimized during construction
621 through the use of WSDOT-approved temporary erosion and sediment
622 control best management practices (BMPs).
623 • Impacts to streams will be minimized during work adjacent to water through
624 the use of approved BMPs.
625 • Prior to the start of construction, all sensitive areas and clearing limits will be
626 marked with high visibility construction fencing, and erosion control devices
627 will be placed to prevent runoff of sediment into areas where no work is
628 proposed (i.e., Springbrook Creek and other wetlands areas). The contractor
629 will confine construction projects to the minimum area necessary to complete
630 the project as defined by the flagged clearing limits.
631 • Excavation and grading in Units C and E will be conducted in the dry prior
632 to breaching the berm along Springbrook Creek.
633 • Breaching of the berm along Springbrook Creek will occur during low flow
634 periods and will not require any in -water work.
635
636 2.3.6.3 Staging
637 Temporary material storage stockpiles will not be placed in the 100-year
638 floodplain between October 1 and May 1. Material used within 72 hours of
639 deposition will not be considered a temporary material storage stockpile. All
640 temporary material storage stockpiles will be protected by appropriate BMPs
641 to prevent sediments from leaving the stockpiles.
642 When practicable, all fueling and maintenance of equipment will occur more
643 than 300 feet from the nearest wetland, ditches, or flowing or standing water
644 Fueling trucks, excavation equipment, and other similar equipment over 300
645 feet away from standing water may not be practicable.
646
Biological Assessment 20 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
647
2.3.6.4
Grubbing and Clearing
648
Vegetation will only be grubbed from areas undergoing permanent alteration
649
and for temporary construction access. All areas grubbed for temporary
650
construction access will be restored when construction is completed.
651
652
2.3.6.5
Herbicide Use
653
Herbicides will be applied in accordance with the herbicide label, by a
654
licensed applicator with an aquatic endorsement.
655
656
2.3.6.6
Trail Construction
657
•
Treated wood will be inspected before installation to ensure that there are not
658
any superficial deposits of preservative material on the wood.
659
•
Treated wood will not be stored within 300 feet of the nearest wetland, ditch,
660
or flowing or standing water, and will remain covered until used.
661
•
Non -creosote -treated wood will be treated using the April 17, 2002 revised
662
Amendment to Best Management Practices for the Use of Treated Wood in
663
Aquatic Environments; USA Version -Revised July 1996-Western Wood
664
Preservers Institute. The Western Wood Preserver Institute BMPs for Treated
665
Wood in Aquatic Applications and amendments can be found at the
666
following link:
667
http:/jwww.wwj2itistitLite.or Tk� mainpa,,,Es/tliebmi2swoodina!�uat.htm.
668
•
Fabrication of the trail will be completed over flowing water.
669
Debris resulting from construction of the boardwalk trail will be contained
670
from entering wetland, ditches, or flowing or standing water through the use
671
of tarps or other containment devices, to the greatest extent possible.
672
673
2.3.6.7
Lighting
674
•
No temporary project light, including mobile units, will shine directly on any
675
waters known to contain listed fish outside of the WDFW in -water work
676
window.
677
0
Within 300 feet of waters known to contain listed fish life, all temporary
678
project lighting will be minimized between sunset and sunrise from
679
November 1 to January 15, and from March 15 to May 15.
Biological Assessment
21 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
680
2.3.6.8 Fish and Wildlife
681
• Construction equipment will not enter any water body without authorization
682
from Washington Department of Fish and Wildlife (WDFW). Equipment
683
shall be operated as far from the water's edge as possible.
684
• WSDOT will provide advance notification to WDFW and Ecology before
685
work in an environmentally sensitive area commences, in accordance with
686
permit conditions.
687
688 2.3.6.9 Bank Protection
689 Living plant material and large woody debris will be incorporated in the
690 bank protection designs where appropriate.
691
692 2.3.6.10 Restoration and Revegetation
693 • Riparian vegetation will be replanted with species native to the region.
694 • Disturbed areas will be replanted with native plant species.
695
696
2.3.6.11 Miscellaneous
697
All excess excavated material will be removed and placed in upland locations
698
where it cannot enter waters of the state.
699
700
2.3.6.12 Construction Monitoring
701
• WSDOT will monitor site construction to assure work is completed according
702
to site plan sheets and permit conditions.
703
• Site elevations will be surveyed routinely in Units C and E during
704
construction to assure elevations are completed as shown on the project
705
plans.
706
• WSDOT will oversee construction to ensure compliance with contract
707
language, special provisions, existing WSDOT environmental procedures,
708
and permit conditions.
709
• Woody habitat structures and plant material will be inspected, properly
710
stored, and installed.
711
Biological Assessment 22 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Proposed Project
712 2.3.6.13 Long Term Maintenance/Compliance
713 • WSDOT and the City of Renton will provide assurance that all long-term
714 compliance expectations are communicated to the responsible parties.
715 • The site will be maintained for a period of 10 years or until performance
716 standards are met, whichever occurs later. Maintenance activities include,
717 but are not limited to, weed control, trash removal, vandalism repair, and
718 structure and/or signage maintenance.
719 • Long-term maintenance (Year 10 through Year 20) will be conducted by the
720 City of Renton to ensure that functional benefits of the Springbrook Bank are
721 not degraded.
722 • All structures and facilities within Springbrook Bank, including fences, the
723 elevated boardwalk, the pump -station diversion pipe and structures, and the
724 stop -log weir, shall be properly maintained in perpetuity or for as long as
725 each is needed to accomplish the goals of Springbrook Bank.
726 • After the 20-year period ends, the City of Renton will continue to manage the
727 site by fulfilling landowner obligations defined in the Conservation Easement
728 to maintain the ecological functions on the site. These obligations include
729 prohibiting activities that may convert the bank site into vacant land such as
730 burning, dumping, or harvesting wood. Landowner obligations also include
731 noxious weed control, emergency control of pests, and maintaining fences to
732 restrict human access.
733
734 2.4 Project Schedule
735 The wetland re-establishment areas in Units C and E, berm breaches in Units A and B, and a
736 portion of the wetland rehabilitation area in Unit C will be excavated and soils amended
737 during the dry weather season in 2007. Berm breaches in Unit E will occur during the dry
738 weather season in 2008. Control of reed canarygrass and Himalayan blackberry may begin
739 in the spring or summer of 2007. Woody plantings in all units will be installed during the
740 wet weather season in 2007/2008. Large woody debris will be installed during the dry
741 weather season in 2007. All berm breaching associated with Springbrook Creek will occur
742 during the WDFW-prescribed work window of June 15 — September 30.
Biological Assessment 23 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Environmental Baseline
743 3 ENVIRONMENTAL BASELINE
744 3.1 Action Area
745 The action area is the area to be affected directly or indirectly by the federal action (50 CFR
746 §402.02). The action area is the defined geographic area potentially affected by the project.
747 For the purposes of establishing baseline conditions from which to evaluate potential effects
748 of the project, the types of activities to be performed and physical site conditions were
749 examined and evaluated. Project components that pose potential impacts to endangered or
750 threatened species and designated critical habitat are construction noise, turbidity, and
751 sedimentation from construction activities. Figure 2 identifies the action area for the project.
Biological Assessment 24 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Environmental Baseline
754 3.1. > Action Area Description
755 The action area extends 800 feet from the project footprint. The 800 foot distance is
756 based on the distance at which construction noise levels are expected to attenuate to
757 background levels, as discussed below in Section 3.1.2, Noise Considerations. Within
758 this action area, waterbodies could be affected by sediment mobilization from
759 construction activities. Springbrook Creek could be affected by sediment mobilization
760 up to 200 feet downstream of construction activities. The distance of sediment
761 mobilization effects to the above -mentioned waterbodies are based on established
762 Ecology mixing zones.
763
764 The action area contains areas designated as Essential Fish Habitat (EFH; PFMC 1999)
765 and is in an area where environmental effects of the proposed project may affect EFH for
766 Chinook and coho (Oncorhynchus kisutch) salmon (PFMC 1999).
767
768 3. f.2 Noise Considerations
769 The project component with the greatest potential to affect endangered or threatened
770 species is noise generated during construction. For the purposes of this BA, the extent of
771 the action area is based on noise effects extending 800 feet from the project footprint.
772 Beyond 800 feet from the project area, construction noise levels are expected to attenuate
773 to background levels.
774
775 Sound is defined as a density disturbance that propagates through a medium. In -air
776 sound measurements are often recorded in dBA using the A -frequency weighing scale.
777 The A -weighted rating of noise is used because it relates to human interpretation of
778 noise. Peak sound emitted from a source is called Lmax. All sounds averaged during a
779 measured period of time are referred to as Leq.
780
781 Noise attenuates as the distance from the source of the noise increases. A general
782 equation shows noise propagation loss as 6 dBA for each doubling distance in areas of
783 hard ground cover. For example, if sound levels were measured at 85 dBA at 50 feet
784 from the source of the noise, at 100 feet the sound would have decreased to 79 dBA, at
785 200 feet it would decrease to 73 dBA, at 400 feet it would be 67 dBA, and so on. In
786 addition, land masses, buildings, and vegetation between a noise source and the
Biological Assessment 26 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Environmental Baseline
787 receptor can greatly reduce recorded noise levels. Freeways and buildings can reduce
788 noise from construction by between 10 and 15 dBA, respectively (USACE and Port of
789 Oakland 1998). Additional factors play into noise attenuation at greater distances from a
790 noise source. Atmospheric absorption effects decrease noise levels by an additional 1
791 dBA beyond 1,000 feet (USACE and Port of Oakland 1998) and molecular absorption
792 accounts for another 1 dBA beyond 2,000 feet (WSDOT 1994b).
793
794 The loudest construction activities anticipated for the project are from heavy equipment,
795 specifically from heavy trucks. In a worst case scenario, heavy trucks are expected to
796 generate Leq levels on the order of 82 — 96 dBA at 50 feet (WSDOT 2005b).
797
798 The project is surrounded by dense industrial and commercial development. Ambient
799 conditions are consistent with urbanized areas and are characterized by heavy truck,
800 helicopter, airplane, train, construction, and other human -induced noise. The site is also
801 in close proximity to the I-405 and SR 167 corridors and local high traffic roads such as
802 Lind Avenue SW and Oakesdale Avenue SW. These factors, as well as frequent
803 residential, commercial, and industrial construction related noise, increase ambient noise
804 levels well above 70 dBA (LaLonde 2005).
805
806 Based on the attenuation rates noted above, noise rates from heavy trucks would
807 attenuate to background levels of 70 dBA between 400 and 800 feet from the source. No
808 other noise impacts from the project would exceed these levels and, therefore, the action
809 area encompasses a worst -case scenario for noise related construction impacts.
810
811 3.2 Physical Indicators
812 3.2. 1 Water Quality
813 3.2.1.1 Temperature
814 Springbrook Creek is currently on the Ecology 303(d) list for exceeding allowable
815 water quality criteria for temperature (Ecology 1998). Water temperatures in some
816 tributaries of the Mill and Springbrook Creek subbasins have been historically high
817 and are probably of concern for salmonid rearing (Kerwin and Nelson 2000).
818
Biological Assessment 27 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Environmental Baseline
819
3.2.1.2 Sediment/Turbidity
820
Stream sediment loading within the SMG basin is contributed from two primary
821
sources: soil erosion and stream channel erosion (City of Renton 1993). Soil erosion
822
is caused primarily by land clearing activities associated with construction and
823
development. Sediment deposits in the lower section of Springbrook Creek have
824
reached depths of 5 feet (King County 1987; Kerwin and Nelson 2000).
825
826 3.2.1.3 Chemical Contamination/Nutrients
827 Springbrook Creek is currently on Ecology's 303(d) list for exceeding allowable
828 water quality criteria for cadmium, chromium, copper, mercury, and zinc (Ecology
829 1998).
830
831 3.2.1.4 Dissolved Oxygen
832 Dissolved oxygen (DO) levels are one of the most significant issues for salmonids in
833 the SMG basin. DO for incubation and rearing is a probable factor of decline for
834 salmonids in several tributaries, particularly Springbrook Creek (Kerwin and Nelson
835 2000).
836
837 3.2.2 Habitat Access
838
3.2.2.1 Physical Barriers
839
The BRPS is located at the most downstream end of Springbrook Creek. Although it
840
is equipped with upstream and downstream passage facilities, the BRPS still poses a
841
barrier to the upstream and downstream movement of salmonids at certain seasons
842
(Harza 1995). The upstream passage facility is normally operated annually from
843
mid -September through the end of January. The BRPS also has a downstream
844
passage facility that is operated Monday through Friday from early April to mid-
845
June each year, for approximately 8 hours per day. Fish attempting to move
846
downstream outside of that operational window are either prevented from exiting
847
the Springbrook system or must pass through the large, unscreened pumps (if
848
operational). Juvenile Chinook emerge and begin moving downstream in the
849
Middle Green River system and Soos Creek as early as February (Jeanes and Hilgert
850
2000). Consequently, early downstream migrants would be prevented from exiting
851
the Springbrook system. Adult salmonids cannot pass downstream via the
Biological Assessment 28 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Environmental Baseline
852 downstream fish passage facility at the BRPS due to the physical limitations of the
853 existing fish passage facility. Chinook salmon have been known to move upstream
854 and become trapped in the Springbrook Creek system, where there is little if any
855 suitable Chinook spawning habitat (Kerwin and Nelson 2000).
856
857 3.2.3 Habitat Elements
858 Under present conditions, the lack of suitable spawning habitat and questionable rearing
859 capacity due to degraded water quality, especially during warm summer months,
860 results in Springbrook Creek offering little in the way of fish habitat (City of Renton
861 1993).
862
863
3.2.3.1 Substrate Embeddedness
864
The lower reaches of Springbrook Creek are contained in the slack water pond
865
behind the BRPS. As a result, Springbrook Creek's in -stream substrate consists
866
exclusively of silts from the BBPS upstream to the SR 167 crossing upstream of the
867
action area (Kerwin and Nelson 2000).
868
869 3.2.3.2 Large Woody Debris
870 In Springbrook Creek, the area parallel and adjacent to SR 167 (within the action
871 area) consists exclusively of silts and contains no large woody debris (Harza 1995).
872
873 3.2.3.3 Pool Frequency and Quality
874 In the Lower Green River Subwatershed, increased fine sediment delivery from
875 upstream reaches and urbanized tributaries is filling pools and substrate interstitial
876 spaces, thereby reducing the amount and quality of habitat available for rearing
877 juvenile salmonids (Kerwin and Nelson 2000). Pool habitat makes up less than 1
878 percent of overall habitat in the lower reach of Springbrook Creek (Harza 1995).
879
880 3.2.3.4 Off -Channel Habitat
881 Within the action area, Springbrook flows mostly parallel and adjacent to SR 167. In
882 this area, the creek resembles a drainage ditch used for water conveyance (Kerwin
883 and Nelson 2000). During site investigations completed for the Springbrook Bank, it
Biological Assessment 29 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Environmental Baseline
884 was observed that this section of Springbrook Creek is entirely contained within
885 levees (earthen berms) for flood control purposes (Koellmann 2005)
886
887 3.2.4 Channel Conditions and Dynamics
888 3.2.4.1 Floodplain Connectivity
889 The entire Springbrook Creek subbasin has been adversely impacted by floodplain
890 modifications, the most significant of which is the BRPS (Kerwin and Nelson 2000).
891 During flood periods on the Green River, the pumping station acts as a dam,
892 preventing water from backing upstream into the lower Springbrook Creek subbasin
893 (Kerwin and Nelson 2000).
894
895 3.2.5 Flow/Hydrology
896 3.2.5.1 Change in Peak/Base Flows
897 Extreme volumes of water associated with storm events has caused streambank
898 erosion, scouring, and siltation in the SMG watershed (Bortz 1981). Low to moderate
899 downcutting in Springbrook Creek has been found in Springbrook Creek (Harza
900 1995).
901
902 3.2.6 Watershed Conditions
903 3.2.6.1 Road Density and Location
904 Road densities in the SMG watershed are greater than 3 miles of linear distance per
905 square mile, with many roads on the valley floor.
906
907 3.2.6.2 Disturbance History
908 It is evident that the creeks in the Springbrook Creek subbasin have undergone
909 extensive alterations to their historic stream channels by their drainage ditch
910 appearance, right angle turns along property lines, and straight channel lines
911 (Kerwin and Nelson 2000).
912
913 3.2.6.3 Riparian Conservation Areas
914 There is no functioning riparian habitat throughout the lower reaches of Mill and
915 Springbrook Creeks. The absence of this habitat contributes to the lack of stream
Biological Assessment 30 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Environmental Baseline
916 channel diversity, complexity, and ultimately successful salmonid rearing
917 capabilities (Kerwin and Nelson 2000).
918
Biological Assessment 31 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Species Occurrence, Effects Analysis, and Effects Determination
919 4 SPECIES OCCURRENCE, EFFECTS ANALYSIS, AND EFFECTS
920 DETERMINATION
921 4.1 Chinook Salmon
922 4. 1. > Status
923 The Puget Sound Chinook salmon ESU is listed as threatened.
924
925 4.1.2 Critical Habitat
926 On August 12, 2005, the National Marine Fisheries Service (NMFS) announced the
927 impending publication of Final Rules Designating Critical Habitat for 12 Evolutionarily
928 Significant Units (ESUs) of Pacific Salmon and Steelhead in Washington, Oregon, and Idaho.
929 These rules were published on September 2, 2005 (50 CFR Part 226), and became
930 effective on January 2, 2006. This designation includes the Puget Sound ESU of Chinook
931 salmon, which is currently listed as threatened under the ESA.
932
933 Critical habitat is designated for areas containing the physical and biological habitat
934 features, or primary constituent elements (PCEs) essential for the conservation of the
935 species or that require special management considerations. PCEs include sites that are
936 essential to supporting one or more life stages of the ESU and which contain physical or
937 biological features essential to the conservation of the ESU. The relevant PCEs related to
938 the project area are:
939 1. Freshwater spawning sites with water quantity and quality conditions and
940 substrate supporting spawning incubation and larval development.
941 2. Freshwater rearing sites with water quantity and floodplain connectivity to form
942 and maintain physical habitat conditions and support juvenile growth, and
943 mobility; water quality and forage supporting juvenile development; and natural
944 cover such as shade, submerged and overhanging large wood, log jams and
945 beaver dams, aquatic vegetation, large rocks and boulders, side channels, and
946 undercut banks.
947 3. Freshwater migration corridors free of obstruction with water quantity and
948 quality conditions and natural cover such as submerged and overhanging large
949 wood, aquatic vegetation, large rocks and boulders, side channels, and undercut
950 banks supporting juvenile and adult mobility and survival.
951
Biological Assessment 32 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Species Occurrence, Effects Analysis, and Effects Determination
952 Springbrook Creek is identified as critical habitat for the Puget Sound ESU of Chinook
953 salmon within the Duwamish Subbasin, Unit 11 (HUC 17110013).
954
955 4.1.3 Biology and Distribution
956 Puget Sound Chinook salmon are anadromous and semelparous. Adult females spawn
957 in redds with suitable gravel size, water depth, and velocity. The female guards the
958 redd for 4 to 25 days before dying (NOAA Fisheries 2004).
959
960 Chinook salmon exhibit great variability with respect to the duration and types of
961 habitats used for rearing. Juveniles can spend several days to a year in freshwater prior
962 to migrating to the estuary (Healey 1991). This variability can occur within a single
963 stock, but more typically, stocks are classified as "ocean type" or "stream type." Ocean
964 type salmon stay in freshwater only briefly (from a few days to several months) and
965 spend a greater amount of time feeding in estuaries than spring type Chinook salmon.
966 Stream type salmon can spend 1 to 2 years in freshwater as juveniles, and migrate
967 rapidly to marine waters. Ocean type Chinook salmon are more common in Puget
968 Sound.
969
970 Chinook salmon generally require habitat diversity within a single stream for their
971 spawning, rearing, and foraging activities. They also require cover for protection from
972 predators. In small streams, undercut banks with slower water velocities are often used
973 for rearing habitat. In larger rivers, nearshore areas of lower water velocity, such as
974 scour pools associated with logs and roots, serve as rearing habitat. Foraging is done in
975 faster waters, but access to lower -velocity areas, such as eddies behind boulders, are
976 important "holding" areas where the salmon can expend less energy while waiting for
977 prey to appear in the faster water (ISPG 2002). Salmonids are closely associated with
978 woody debris, which offers cover from predators (ISPG 2002).
979
980 Chinook salmon are presumed to use Springbrook Creek in the action area for rearing,
981 migration, and foraging. Chinook spawning likely occurs upstream of the action area,
982 as little to no suitable Chinook salmon spawning habitat exists within or downstream of
983 the action area.
Biological Assessment 33 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Species Occurrence, Effects Analysis, and Effects Determination
984 4.9.4 Direct and Indirect Effects
985 Direct effects that could result in impacts to Chinook salmon as a result of the project
986 include temporary construction impacts, including increases in sedimentation/turbidity,
987 vegetation removal, noise, and hazardous material spills, and overall improvements to
988 Chinook habitat resulting from changes to hydraulics, hydrology, and habitat
989 conditions.
990
991 4.1.4.1 Sedimentation/Turbidity
992 Excavation and grading could introduce fine sediments into Springbrook Creek
993 through erosion and sedimentation. Excessive fine sediment input into streams can
994 result in multiple impacts to salmonids. Potential impacts from erosion and
995 sedimentation include smothered salmon eggs in gravels and decreased micro and
996 macro invertebrate salmonid prey survival as a result of reduced DO; reduced visual
997 predators' capacity to capture prey, damaged gills and increased risk of anoxia (the
998 absence or reduced supply of oxygen in arterial blood or tissues), behavioral
999 changes, and stress that can lead to fish mortality.
1000
1001 Sedimentation will be highest in areas where construction activities occur adjacent to
1002 Springbrook Creek. Units A, B, and E will be affected by grading and excavation
1003 activities, mowing of invasive plant species, and placement of erosion control
1004 measures that may temporarily disturb soil resulting in erosion and sedimentation.
1005 The majority of these activities will be completed prior to breaching the berms that
1006 separate Units A, B, and E from Springbrook Creek, allowing for the berms to
1007 contain construction related sediment from entering Springbrook Creek. Breaching
1008 of the berms will occur during summer low flows to further limit sediment from
1009 entering Springbrook Creek.
1010
1011 BMPs, conservation measures, and performance standards will be implemented to
1012 minimize the impacts of sedimentation and turbidity. Turbidity levels will not
1013 exceed maximums defined by Ecology's Water Quality Certification (WQC). Even
1014 with BMPs, short-term effects to water quality from sediment (such as temporary
1015 increases in stream turbidity) are possible, particularly during storm events.
Biological Assessment 34 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Species Occurrence, Effects Analysis, and Effects Determination
1016 However, in general, these effects are expected to be small in magnitude and not
1017 likely to cause harm to fish.
1018
1019 4.1.4.2 Vegetation Removal
1020 Removal of riparian vegetation can affect fish by increasing stream temperature and
1021 potentially reducing DO, reducing the potential for large woody debris recruitment
1022 and contribution of organic material for macroinvertebrates, eliminating in- and
1023 over -stream cover, and decreasing bank stability.
1024
1025
Temporary riparian impacts will occur within Units A, B, and E within the project
1026
area when riparian buffers are enhanced by mowing invasive vegetation, installing
1027
erosion control measures, and planting or underplanting with native vegetation.
1028
Although existing riparian conditions vary, the majority of buffers in the action area
1029
are currently moderately to severely degraded. Therefore, many of the functions
1030
that riparian vegetation provides are already altered and will not be substantially
1031
affected as compared to existing conditions (WSDOT 2005c).
1032
1033
In areas where vegetation is temporarily removed, it will be replaced with native
1034
plant species appropriate for the project area. In addition, non-native invasive plant
1035
species will be removed and/or controlled throughout the project area.
1036
1037
The project will ultimately result in an overall increase in the amount and quality of
1038
riparian and upland vegetation in the action area.
1039
1040
4.1.4.3 Noise
1041
Although effects to fish from above -water construction noise are not as well
1042
understood as the impacts of underwater noise (pile driving), construction noise in
1043
general could disturb or displace fish near the project. Fish that are disturbed or
1044
displaced could alter their migratory behavior through actions such as holding up-
1045
or downstream for extended periods. Construction noise can also result in increased
1046
fish predation if fish are displaced from cover or habituated to excessive noise,
1047
which could decrease their ability to detect approaching predators.
Biological Assessment 35 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Species Occurrence, Effects Analysis, and Effects Determination
1048 Noise impacts will be greatest during construction along Springbrook Creek;
1049 however, this area is already exposed to a high level of ambient noise (highways,
1050 airport, railroad, and industry). Any noise impacts to fish will be minimized by
1051 limiting the timeframe associated with breaching of the berms next to Springbrook
1052 Creek to the WDFW in -water work window, when the fewest number of fish are
1053 expected to be present, and completing the work during summer low -flow
1054 conditions. In addition, pile driving has been eliminated from the design of this
1055 project.
1056
1057 4.1.4.4 Exposure to Hazardous Materials
1058 Hazardous materials could have lethal or sublethal effects on fish and micro- and
1059 macroinvertebrate prey within the action area. During construction, oil, fuel,
1060 industrial fluid, grease, paint, solvents, concrete, asphalt, tar, heavy metals, and
1061 other hazardous materials from construction equipment could enter Springbrook
1062 Creek. Contaminants can be suspended in the water column or settled on the
1063 bottom and may adhere to sediment particles. Many heavy metals and persistent
1064 organic compounds such as pesticides and polychlorinated biphenyls (PCBs) tend to
1065 adhere to solid particles. As the particles are deposited, these compounds or their
1066 degradation products can bioaccumulate in benthic organisms at much higher
1067 concentrations than in the surrounding waters. Contaminants can be assimilated
1068 into fish tissues by absorption across the gills or through bioaccumulation as a result
1069 of consuming contaminated prey or incidental consumption of sediments.
1070
1071 Impacts to listed species from construction of the trail include introduction of
1072 chemical contaminants (e.g., copper) from wood leachate and wood fragments from
1073 construction resulting in harm or mortality, avoidance reactions by fish from
1074 exposure to contaminants, and impacts from noise associated with construction of
1075 the trail. Drilling and cutting of treated wood may introduce contaminated wood
1076 fragments into aquatic habitat (Lebow et al. 2001). Exposure to precipitation may
1077 result in chemical contaminants from the wood being leached into the surrounding
1078 environment. Possible impacts associated with avoidance behavior include fish
1079 avoiding structures and becoming more subject to predation, or moving out of a
1080 stream system earlier than they otherwise would, leading to decreased survival.
Biological Assessment 36 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Species Occurrence, Effects Analysis, and Effects Determination
1081
Displaced fish may have to spend more time and energy procuring food if a
1082
structure is installed in a productive nursery area (Poston 2001).
1083
1084
Although treated wood contains chemicals that are potentially toxic, studies indicate
1085
that there are no measurable impacts on aquatic organisms if the wood is properly
1086
treated and installed. The potential environmental impact of treated wood can be
1087
minimized by specifying that the wood be treated using methods that ensure
1088
chemical fixation and prevent the formation of surface residues or bleeding of
1089
preservative. In addition, responsible construction practices, such as storage of
1090
treated wood under cover and containment and collection of construction residue,
1091 can further reduce the possibility of negative environmental impacts (Lebow et al.
1092 2001). Additionally, computer modeling and empirical evidence suggest that the use
1093 of waterborne wood preservatives in fresh or marine waters is not likely to increase
1094 dissolved copper concentrations by detectable amounts (Brooks 2004).
1095
1096 A SPCC Plan for the project will be prepared and submitted by the contractor to the
1097 project engineer prior to commencing any construction. BMPs will be implemented
1098 during project construction to reduce or eliminate potential sources of hazardous
1099 material contamination. Construction equipment will not enter Springbrook Creek
1100 below the wetted perimeter of the creek as breaching of the berms on Units A, B, and
1101 E will occur during summer low flows. Additional BMPs, conservation measures,
1102 and performance standards will be implemented to avoid, minimize, and control
1103 potential discharges of hazardous materials into the environment.
1104
1105 4.1.4.5 Modifications of Habitat Conditions
1106 The project will restore, rehabilitate, and enhance wetland and riparian areas, and
1107 enhance upland buffers throughout the project area. Habitat improvements include
1108 removal of invasive plant communities and replacement of those communities with
1109 diverse, native, multi -strata vegetation that will provide increased opportunity for
1110 food and shelter. Reconnecting Springbrook Creek to its floodplain will provide
1111 wider stream margins with slower velocity waters, which will provide off -channel
1112 refugia habitat for juvenile salmonids. Placement of large woody debris and other
1113 special habitat features within Springbrook Creek's floodplain and the associated
Biological Assessment 37 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Occurrence, Effects Analysis, and Effects Determination
1114 uplands will provide cover for prey species and salmonids. Improved groundwater
1115 connectivity will increase groundwater recharge and improve water quality by
1116 contributing cooler, cleaner water to Springbrook Creek.
1117
1118 4.1.4.6 Fish Stranding
1119 The berms that presently separate Springbrook Creek from Units A, B, and E will be
1120 breached to reconnect Springbrook Creek to its historic floodplain. The berms on
1121 Units A and B will be breached at an approximately 12 foot elevation to allow
1122 inundation during the 2-year flood event. Unit E will be breached at an
1123 approximately 8-foot elevation and will be inundated during typical Springbrook
1124 Creek baseflow. The existing berms are designed for flood protection up to the 25-
1125 year flood event (14.5 feet in elevation) and in some locations up to the 100-year
1126 event (15.0 feet in elevation) per the Hydrological Simulation Program - FORTRAN
1127 (HSPF) model dated May 2005. Unit E will be graded such that all water will
1128 directly drain out of the unit as floodwaters recede. However, Units A and B will
1129 have areas at elevations lower than 12 feet that will retain water after the
1130 floodwaters recede.
1131
1132 During flood events, juvenile salmon, like many small fishes, seek out shallow water
1133 areas with low velocities (Everest and Chapman 1972, Roper et al. 1994, and
1134 Bradford and Higgins 2001). Studies on juvenile Chinook behavior in floodplains
1135 show that juvenile Chinook salmon do not appear to be especially prone to stranding
1136 mortality, distribute equally throughout the entire floodplain during flood events,
1137 and show no obvious preferences for pools, heavy vegetation, or deep water habitats
1138 (i.e., depression zones) (Sommer et al. 2005; Sommer et al. 2001). Therefore, natural
1139 juvenile Chinook salmon behavior will limit stranding in Units A and B.
1140
1141 In larger flood events, such as a 25-year or greater event, the existing berms in the
1142 Springbrook system will overtop. These overtopping events will result in juvenile
1143 fish seeking shallower water areas with low velocities similar to those found
1144 landward of the overtopped berms. As floodwaters recede, the potential for juvenile
1145 fish stranding landward of the berms increases significantly because, once the
1146 floodwaters recede to below the level of the berms, fish have no opportunity to
Biological Assessment 38 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Species Occurrence, Effects Analysis, and Effects Determination
1147 access Springbrook Creek. In comparison, the built project will contain flood events
1148 of this magnitude within Units A and B and the associated floodwaters will
1149 ultimately drain out of these units. Therefore, although the potential for stranding
1150 still exists, the built project will result in a far lower number of stranded fish than
1151 under present conditions.
1152
1153 Additional information on fish stranding can be found in Appendix D: Fisheries
1154 Review White Paper.
1155
1156 4.1.5 Effects Determination
1157 The activities described in this BA will not result in long-term, permanent impacts to
1158 Chinook salmon populations. Construction activities may result in temporary impacts
1159 to water quality, noise increases, and stream -side vegetation. However, pile driving has
1160 been eliminated from this project and no other in -water work is planned in the action
1161 area. In addition, construction activities immediately adjacent to Springbrook Creek will
1162 be performed during the WDFW work window when Chinook salmon are least likely to
1163 be present. Treated lumber will be used for decking associated with the boardwalk trail
1164 in Unit A, but through use of BMPs during construction and Copper Azole treated
1165 wood, impacts from treated wood will be minimized. Over time, the project will result
1166 in improved habitat conditions for Chinook salmon through increased floodplain
1167 connectivity, improved water quality and water quantity conditions, increased habitat
1168 complexity, and restoration of native riparian plant communities throughout the project
1169 area. Therefore, it is concluded that the project may affect, but is not likely to
1170 adversely affect, Chinook salmon.
1171
1172 4. >.6 Critical Habitat Effects Determination
1173 The action area falls within designated critical habitat for Puget Sound ESU of Chinook
1174 salmon. Chinook salmon are presumed to use Springbrook Creek in the action area for
1175 rearing, migration, and foraging. There is no suitable Chinook salmon spawning
1176 habitat, and limited migration, rearing and foraging opportunities exist in the action
1177 area. Construction activities associated with the project will not degrade critical habitat
1178 due to permit timing conditions and the use of BMPs. Floodplain connectivity, water
1179 quality and quantity conditions, and the amount of in -stream habitat in Springbrook
Biological Assessment 39 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Occurrence, Effects Analysis, and Effects Determination
1180 Creek to support rearing and migration will be improved as a result of the project.
1181 Natural cover throughout the project area will be increased allowing for better
1182 opportunity for adult and juvenile mobility and survival. Therefore, the project may
1183 affect, but is not likely to adversely affect, Puget Sound ESU Chinook salmon critical
1184 habitat.
1185
1186 4.2 Bull Trout
1187 4.2. 1 Status
1188 Bull trout are listed as threatened in Puget Sound.
1189
1190 4.2.2 Critical Habitat
1191
1192 Springbrook Creek has not been designated as bull trout critical habitat.
1193
1194 4.2.3 Biology and Distribution
1195 Bull trout are members of the char subgroup of the salmon family. The anadromous
1196 type inhabits upper tributary streams and lake and reservoir systems. Bull trout feed on
1197 terrestrial and aquatic insects, and as they grow in size, their diets include whitefish,
1198 sculpins, and other trout. Bull trout spawn from August through November when they
1199 reach maturity, between 4 and 7 years, and when temperatures begin to drop, in cold,
1200 clear streams. Bull trout can spawn repeatedly, and can live over 20 years. Adults and
1201 juveniles return to the marine environment between May and early July. Resident forms
1202 of bull trout spend their entire lives in freshwater, while anadromous forms live in
1203 tributary streams for 2 or 3 years before migrating to estuaries as smolts. Char species
1204 are generally longer -lived than salmon; bull trout up to 12 years old have been identified
1205 in Washington (Brown 1992).
1206
1207 Bull trout habitat requirements are similar to those of Chinook and coho salmon, but
1208 they need slightly colder water temperatures for successful spawning (ISPG 2002).
1209
1210 Adult bull trout is the only life history stage likely to occur in the action area, though
1211 their presence is unlikely due to the water quality found in Springbrook Creek.
1212
Biological Assessment 40 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Occurrence, Effects Analysis, and Effects Determination
1213 4.2.4 Direct and Indirect Effects
1214 Direct effects that could result in impacts to bull trout as a result of the project include
1215 temporary construction impacts, including increases in sedimentation/turbidity,
1216 vegetation removal, noise, and hazardous material spills, and overall improvements to
1217 bull trout habitat resulting from changes to hydraulics, hydrology, and habitat
1218 conditions. There are no indirect effects resulting from the built project that will impact
1219 bull trout.
1220
1221 4.2.4.1 Sedimentation/Turbidity
1222 Excavation and grading could introduce fine sediments into Springbrook Creek
1223 through erosion and sedimentation. Excessive fine sediment input into streams can
1224 result in multiple impacts to salmonids. Potential impacts from erosion and
1225 sedimentation include smothered salmon eggs in gravels and decreased micro and
1226 macro invertebrate salmonid prey survival as a result of reduced DO, reduced visual
1227 predators' capacity to capture prey, damaged gills and increased risk of anoxia (the
1228 absence or reduced supply of oxygen in arterial blood or tissues), behavioral
1229 changes, and stress that can lead to fish mortality.
1230
1231 Sedimentation will be highest in areas where construction activities occur adjacent to
1232 Springbrook Creek. Units A, B, and E will be affected by grading and excavation
1233 activities, mowing of invasive plant species, and placement of erosion control
1234 measures that may temporarily disturb soil resulting in erosion and sedimentation.
1235 The majority of these activities will be completed prior to breaching the berms that
1236 separate Units A, B, and E from Springbrook Creek, allowing for the berms to
1237 contain construction -related sediment from entering Springbrook Creek. Breaching
1238 of the berms will occur during summer low flows to further limit sediment from
1239 entering Springbrook Creek.
1240
1241 BMPs, conservation measures, and performance standards will be implemented to
1242 minimize the impacts of sedimentation and turbidity. Turbidity levels will not
1243 exceed maximums defined by Ecology's WQC. Even with BMPs, short-term effects
1244 to water quality from sediment (such as temporary increases in stream turbidity) are
Biological Assessment 41 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Occurrence, Effects Analysis, and Effects Determination
1245 possible, particularly during storm events. However, in general, these effects are
1246 expected to be small in magnitude and not likely to cause harm to fish.
1247
1248 4.2.4.2 Vegetation Removal
1249 Removal of riparian vegetation can affect fish by increasing stream temperature and
1250 potentially reducing DO, reducing the potential for large woody debris recruitment
1251 and contribution of organic material for macroinvertebrates, eliminating in- and
1252 over -stream cover, and decreasing bank stability.
1253
1254 Temporary riparian impacts will occur within Units A, B, and E within the project
1255 area when riparian buffers are enhanced by mowing invasive vegetation, installing
1256 erosion control measures, and planting or underplanting with native vegetation.
1257 Although existing riparian conditions vary, the majority of buffers in the action area
1258 are currently moderately to severely degraded. Therefore, many of the functions
1259 that riparian vegetation provides are already altered and will not be substantially
1260 affected as compared to existing conditions (WSDOT 2005c).
1261
1262 In areas where vegetation is temporarily removed, it will be replaced with native
1263 plant species appropriate for the project area. As a result, the project will result in
1264 enhancement of 14.68 acres of upland and riparian habitat areas, and enhancement
1265 and protection an additional 9.86 acres of wetland and upland habitat through
1266 establishing the 40-foot-wide setback buffer. In addition, non-native invasive plant
1267 species will be removed and/or controlled throughout the project area.
1268
1269 4.2.4.3 Noise
1270 Although impacts to fish from above -water construction noise are not as well
1271 understood as the impacts of underwater noise (pile driving), construction noise in
1272 general could disturb or displace fish near the project. Fish that are disturbed or
1273 displaced could alter their migratory behavior through actions such as holding up-
1274 or downstream for extended periods. Construction noise can also result in increased
1275 fish predation if fish are displaced from cover or habituated to excessive noise,
1276 which could decrease their ability to detect approaching predators.
Biological Assessment 42 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Occurrence, Effects Analysis, and Effects Determination
1277 Noise impacts will be greatest during construction along Springbrook Creek;
1278 however, this area is already exposed to a high level of ambient noise (highways,
1279 airport, railroad, and industry). Any noise impacts to fish will be minimized by
1280 limiting the timeframe associated with breaching of the berms next to Springbrook
1281 Creek to the WDFW in -water work window, when the fewest number of fish are
1282 expected to be present, and completing the work during summer low -flow
1283 conditions. In addition, no pile driving is planned for the project.
1284
1285 4. Z 4.4 Exposure to Hazardous Materials
1286 Hazardous materials could have lethal or sublethal affects on fish and micro- and
1287 macroinvertebrate prey within the action area. During construction, oil, fuel,
1288 industrial fluid, grease, paint, solvents, concrete, asphalt, tar, heavy metals, and
1289 other hazardous materials from construction equipment could enter Springbrook
1290 Creek. Contaminants can be suspended in the water column or settled on the
1291 bottom, and may adhere to sediment particles. Many heavy metals and persistent
1292 organic compounds such as pesticides and PCBs tend to adhere to solid particles. As
1293 the particles are deposited, these compounds or their degradation products can
1294 bioaccumulate in benthic organisms at much higher concentrations than in the
1295 surrounding waters. Contaminants can be assimilated into fish tissues by absorption
1296 across the gills or through bioaccumulation as a result of consuming contaminated
1297 prey or incidental consumption of sediments.
1298
1299 Impacts to listed species from construction of the trail include introduction of
1300 chemical contaminants (e.g., copper) from wood leachate and wood fragments from
1301 construction resulting in harm or mortality, avoidance reactions by fish from
1302 exposure to contaminants, and impacts from noise associated with construction of
1303 the trail. Drilling and cutting of treated wood may introduce contaminated wood
1304 fragments into aquatic habitat (Lebow et al. 2001). Exposure to precipitation may
1305 result in chemical contaminants from the wood being leached into the surrounding
1306 environment. Possible impacts associated with avoidance behavior include fish
1307 avoiding structures and becoming more subject to predation, or moving out of a
1308 stream system earlier than they otherwise would leading to decreased survival.
Biological Assessment 43 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Occurrence, Effects Analysis, and Effects Determination
1309 Displaced fish may have to spend more time and energy procuring food if a
1310 structure was installed in a productive nursery area (Poston 2001).
1311
1312 Although treated wood contains chemicals that are potentially toxic, studies indicate
1313 that there are no measurable impacts on aquatic organisms if the wood is properly
1314 treated and installed. The potential environmental impact of treated wood can be
1315 minimized by specifying that the wood be treated using methods that ensure
1316 chemical fixation and prevent the formation of surface residues or bleeding of
1317 preservative. In addition, responsible construction practices, such as storage of
1318 treated wood under cover and containment and collection of construction residue,
1319 can further reduce the possibility of negative environmental impacts (Lebow et al.
1320 2001). Additionally, computer modeling and empirical evidence suggest that the use
1321 of waterborne wood preservatives in fresh or marine waters is not likely to increase
1322 dissolved copper concentrations by detectable amounts (Brooks 2004).
1323
1324 A SPCC Plan for the project will be prepared and submitted by the contractor to the
1325 project engineer prior to commencing any construction. BMPs will be implemented
1326 during project construction to reduce or eliminate potential sources of hazardous
1327 material contamination. Construction equipment will not enter Springbrook Creek
1328 below the wetted perimeter of the creek as breaching of the berms on Units A, B, and
1329 E will occur during summer low flows. Additional BMPs, conservation measures,
1330 and performance standards will be implemented to avoid, minimize, and control
1331 potential discharges of hazardous materials into the environment.
1332
1333 4.2.4.5 Modifications of Habitat Conditions
1334 The project will restore, rehabilitate, and enhance wetland and riparian areas and
1335 enhance upland buffers throughout the project area. Habitat improvements include
1336 removal of invasive plant communities and replacement of those communities with
1337 diverse, native, multi -strata vegetation that will provide increased opportunity for
1338 food and shelter. Reconnecting Springbrook Creek to its floodplain will provide
1339 wider stream margins with slower velocity waters, which will provide off -channel
1340 refugia habitat for juvenile salmonids. Placement of large woody debris and other
1341 special habitat features within Springbrook Creek's floodplain and the associated
Biological Assessment 44 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Occurrence, Effects Analysis, and Effects Determination
1342 uplands will provide cover for prey species and salmonids. Improved groundwater
1343 connectivity will increase groundwater recharge and improve water quality by
1344 contributing cooler, cleaner water to Springbrook Creek.
1345
1346 4.2.5 Effects Determination
1347 The activities described in this BA will not result in long-term, permanent impacts to
1348 bull trout populations. Construction activities may result in temporary impacts to water
1349 quality, noise increases, and stream -side vegetation. However, no pile driving is
1350 planned in the action area and no in -water work will occur. Treated lumber will be used
1351 for decking associated with the boardwalk trail in Unit A, but through use of BMPs
1352 during construction and Copper Azole treated wood, impacts from treated wood will be
1353 minimized. Over time, the project will result in improved habitat conditions for bull
1354 trout through increased floodplain connectivity, improved water quality and water
1355 quantity conditions, increased habitat complexity, and restoration of native riparian
1356 plant communities throughout the project area. Therefore, it is concluded that the
1357 project may affect, but is not likely to adversely affect, bull trout.
1358
1359 4.2.6 Critical Habitat Effects Determination
1360 Springbrook Creek has not been designated as bull trout critical habitat.
1361
1362 4.3 Bald Eagle
1363 4.3.1 Status
1364 Bald eagles are listed as threatened.
1365
1366 4.3.2 Critical Habitat
1367 No critical habitat has been designated for bald eagles.
1368
1369 4.3.3 Biology and Distribution
1370 4.3.3.1 Nesting
1371 Nesting occurs from January 1 to August 15 (USFWS 1986). Abundant food is
1372 critical during nesting because young bald eagles are less tolerant to food
Biological Assessment 45 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Occurrence, Effects Analysis, and Effects Determination
1373 deprivation than adults. Bald eagle nests are frequently associated with water, such
1374 as the Puget Sound, and most often occur close to shorelines.
1375
1376 The Pacific States Bald Eagle Recovery Plan (USFWS 1986) recommends limiting
1377 construction activities near bald eagle nests during critical wintering and nesting
1378 periods. The plan recommends construction and disturbance setbacks of 400 meters
1379 (1,313 feet) if the nest does not have a line of sight to the proposed construction
1380 activity, or 800 meters (2,625 feet) if the nest is within line of sight of construction.
1381 The nearest eagle nest is approximately 2.1 miles from the project area and 1.9 miles
1382 from the 0.2 mile action area boundary. The eagle's territory extends no closer than
1383 1.8 miles to the project area.
1384
1385 4.3.3.2 Foraging
1386 Foraging habitat for bald eagles is typically associated with water features such as
1387 rivers, lakes, and coastal shorelines where fish, waterfowl, and seabirds are preyed
1388 upon. Bald eagle foraging is opportunistic and they feed on dead or weakened prey.
1389 Their diets include fish such as salmon, catfish, pollock, cod, rockfish, carp, dogfish,
1390 sculpin, and hake. They also feed on marine birds and their offspring, and small
1391 terrestrial mammals. They prefer high structures for perching such as trees along
1392 the shoreline, but will also use other structures such as cliffs, piling, and open
1393 ground. They are usually seen foraging in open areas with wide views (Stalmaster
1394 and Newman 1979).
1395
1396 The Lake Washington shoreline, especially on Mercer Island across the water from
1397 the project area, provides good foraging habitat. Piling in the lake, both abandoned
1398 and part of actively used structures, furnish above -water perches in many places
1399 along the shoreline. The developed area close to the highway is of lower quality,
1400 supporting few prey mammals and lacking in suitable perching viewpoints.
1401
1402 4.3.3.3 Perching
1403 Perch sites may be used for activities including hunting, prey consumption,
1404 signaling territory occupation, and resting. Perches are most often associated with
1405 food sources near water and will have visual access to adjacent habitats (Stalmaster
Biological Assessment 46 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
Species Occurrence, Effects Analysis, and Effects Determination
1406
and Newman 1979). Bald eagles will often choose the highest tree on the edge of a
1407
stand, selecting the strongest lateral branches. Migrating eagles could fly over the
1408
site, but are unlikely to forage or perch there due to the lack of suitable perching
1409
trees and the limited prey availability.
1410
1411
4.3.3.4 Wintering
1412
Wintering activities for bald eagles occur from October 31 through March 31.
1413
During the winter months, bald eagles forage, construct nests, and engage in
1414
courtship activities. There may also be bald eagles from outside the region that
1415
forage along the coastline of Puget Sound in the winter. Winter is a high -stress
1416
period for bald eagles because food is scarce and adverse weather requires the birds
1417
to expend more energy to survive. There is no known bald eagle wintering habitat
1418
in the project action area. The nearest eagle territory does not extend to the project
1419
action area boundary.
1420
1421
4.3.4 Direct and Indirect Effects
1422 No bald eagle nesting, foraging, perching, or wintering habitat is documented in the
1423 action area and the nearest eagle territory does not extend to the project action area
1424 boundary. Therefore, there are no identified direct or indirect effects on bald eagles.
1425
1426 4.3.5 Effects Determination
1427 The closest bald eagle nest to the project is located 2.1 miles away and the nearest bald
1428 eagle territory is located 1.9 miles from the action area. In addition, bald eagles are not
1429 known to use or depend on habitat within the action area for perching, foraging,
1430 nesting, or roosting. Therefore, it is concluded that the project will have no effect on
1431 bald eagles.
1432
Biological Assessment 47 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
References
1433 5 REFERENCES
1434 Antieau, Clayton J. 1998. Biology and Management of Reed Canarygrass, and Implications for
1435 Ecological Restoration. Washington State Department of Transportation, Seattle, WA.
1436 http://w,.,vw.semw.org/docs.RCG.rtf
1437
1438 Bortz, B. 1981. Streambed, habitat, beneficial use and recommendations towards enhancement
1439 of Kent stream ecosystems. City of Kent Planning Department. 58 pp.
1440
1441 Bradford, M. and P. Higgins. 2001. Habitat-, season-, and size -specific variation in diel activity
1442 patterns of juvenile Chinook salmon (Oncorhynchus tshawytscha) and steelhead trout
1443 (Oncorhynchus mykiss). Canadian Journal of Fisheries and Aquatic Sciences 58:365-374.
1444
1445 Brooks, Kenneth. 2004. The affects of dissolved copper on salmon and the environmental
1446 affects associated with the use of wood preservatives in aquatic environments. Prepared
1447 for: Western Wood Preservers Institute. Vancouver, WA.
1448
1449 Brown, L. G. 1992. Draft management guide for the bull trout Salvelinus confluentus (Suckley)
1450 on the Wenatchee National Forest. Washington Department of Wildlife, Wenatchee,
1451 Washington. 75 pp.
1452
1453 Everest, F., and D. Chapman. 1972. Habitat selection and spatial interaction by juvenile
1454 Chinook salmon and steelhead trout in two Idaho streams. J. of the Fisheries Research
1455 Board of Canada 29(1):91-100.
1456
1457 Washington Department of Ecology (Ecology). 1998. Department of Ecology decision matrix
1458 for surface waters listed under section 303(d) included in 305B report of the Federal
1459 Clean Water Act (CWA). Ecology, Olympia, Washington.
1460
1461 Harza. 1995. Final Report — Comprehensive Fisheries Assessment of the Mill Creek, Garrison
1462 Creek and Springbrook Creek System. Prepared for the City of Kent, Washington.
1463
Biological Assessment 48 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
References
1464 Healey, M.C. 1991. Life history of chinook salmon (Oncorhynchus tshawytscha). Pages 311-393
1465 in C. Groot and L. Margolis (eds) Pacific Salmon Life Histories. University of British
1466 Columbia Press, Vancouver, British Columbia.
1467
1468 Integrated Streambank Protection Guidelines (ISPG). 2002. Washington State Aquatic Habitat
1469 Guidelines Program. A joint program comprising Washington Department of Fish and
1470 Wildlife, Washington Dept. of Ecology, and Washington State Dept. of Transportation.
1471
1472 Jeanes, E.D. and P. J. Hilgert. 2000. Juvenile salmonid use of lateral stream habitats in the
1473 Middle Green River, Washington. Report prepared for U.S. Army Corps of Engineers,
1474 Seattle District and City of Tacoma Public Utilities, Tacoma WA.
1475
1476 Kerwin, John and Nelson, Tom S. (Eds.). 2000. Habitat Limiting Factors and Reconnaissance
1477 Assessment Report, Green/Duwamish and Central Puget Sound Watersheds (WRIA 9
1478 and Vashon Island). Washington Conservation Commission and the King County
1479 Department of Natural Resources.
1480
1481 King County. 1987. Basin Reconnaissance report No. 14: Black River basin. Natural Resources
1482 and Parks Division and Surface Water Management Division, Seattle, WA.
1483
1484 Koellmann, Derek. 2005. Anchor Environmental, L.L.C. Personal observation during
1485 Springbrook Bank site review, July, 2005.
1486
1487 LaLonde. 2005. Personal communication between Ginette LaLonde of Jones & Stokes and
1488 Derek Koellmann of Anchor Environmental, L.L.C. September 2005.
1489
1490 Lebow, Stan T.; Tippie, Michael. 2001. Guide for minimizing the effect of preservative -treated
1491 wood on sensitive environments. Gen. Tech. Rep. FPL-GTR-122. Madison, WI: U.S.
1492 Department of Agriculture, Forest Service, Forest Products Laboratory. 18 p.
1493 httl2-[/www.f421.fs.fed.us/documnts/12df2004/fpl 20041ebow002.pdf
1494
1495 NOAA Fisheries. 2004. Office of Protected Resources. Chinook Salmon (Oncorhynchus
1496 tshawytscha). littp://www.nmfs.noaa.gov/prot res/species/fish/Chinook salmon.html
Biological Assessment 49 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
References
1497 Pacific Fishery Management Council (PFMC). 1999. Identification and Description of Essential
1498 Fish Habitat, Adverse Impacts and Recommended Conservation Measures for Salmon.
1499 Amendment 14 to the Pacific Coast Salmon Plan, Appendix A. PFMC. Portland, Oregon.
1500
1501 Poston, Ted. 2001. Treated Wood Issues Associated with Overwater Structures in Freshwater
1502 and Marine Environments. Prepared for the Washington State Departments of
1503 Transportation, Fish and Wildlife, and Ecology. Olympia, Washington.
1504
1505 Reinhardt, Carrie and Susan M. Galatowitsch. 2004. Best Management Practices for the
1506 invasive Phalaris arundinacea L. (reed canary grass) in Wetland Restorations.
1507 Minnesota Department of Transportation, St. Paul, MN [Final Report, May 20041.
1508 http://www.fws.gov/shorebirdplan[USShorebird/downloads/ReedCanaryGrassReport2O
1509 04.pdf
1510
1511 Renton, City of. 1993. Black River Basin Draft Water Quality Management Plan. Prepared by
1512 R.W. Beck and Associates and Herrera Environmental Consultants. Renton, WA.
1513
1514 Roper, B., D. Scarnecchia, and T. La Marr. 1994. Summer distribution and habitat use by
1515 Chinook salmon and steelhead within a major basin of the South Umpqua River,
1516 Oregon. Transactions of the American Fisheries Society 123(3):298-308.
1517
1518 Sommer, T., M. Nobriga, W. Harrell, W. Batham, and W. Kimmerer. 2001. Floodplain rearing
1519 of juvenile Chinook salmon: evidence of enhanced growth and survival. Canadian
1520 Journal of Fisheries and Aquatic Sciences 58:325-333.
1521
1522 Sommer, T., W. Harrell, and M. Nobriga. 2005. Habitat use and stranding risk of juvenile
1523 chinook salmon on a seasonal Foodplain. North American J. of Fish. Management.
1524 25:1493-1504.
1525
1526 Stalmaster, M.V. and J.R. Newman. 1979. Perch -site preferences of wintering bald eagles in
1527 northwest Washington. Journal of Wildlife Management. 43:221-224.
1528
Biological Assessment SO January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank
References
1529 Tu, Mandy. 2004. Reed Canarygrass: Control and Management in the Pacific Northwest. The
1530 Nature Conservancy, Portland, OR.
1531 http://tncweeds.ucdavis.edu/moredoc:slphaaruOl.pdf
1532
1533 U.S. Army Corps of Engineers (USACE) and Port of Oakland. 1998. Oakland Harbor
1534 Navigation Improvement [-50 foot] Project Environmental Impact Statement 1998-
1535 http://www.50ftdredge.com/EIS/ EIS_5.8.html
1536
1537 USACE et al. 1995. Federal Guidance for the Establishment, Use, and Operation of Mitigation
1538 Banks. Vol. 60, No. 228, pp 228, pp. 58605-58614. November 28,1995
1539
1540 U.S. Fish and Wildlife Service (USFWS). 1986. Recovery Plan for the Pacific Bald Eagle.
1541 Portland, Oregon. 160 pp.
1542
1543 Washington State Department of Transportation (WSDOT). 1994a. Washington State
1544 Department of Transportation Wetland Compensation Bank Program Memorandum of
1545 Agreement. Signatories include U.S. Army Corps of Engineers, U.S. Environmental
1546 Protection Agency, U.S. Fish and Wildlife Service, National Marine Fisheries Service,
1547 Federal Highway Administration, Washington State Department of Fish and Wildlife,
1548 and Washington State Department of Transportation.
1549
1550 WSDOT. 1994b. Field note sound level measurements, Friday Harbor Wingwall Replacement,
1551 December 1994.
1552
1553 WSDOT. 2005a. Draft Springbrook Creek Wetland and Habitat Mitigation Bank, Mitigation
1554 Bank Instrument. October 19, 2005
1555
1556 WSDOT. 2005b. Advanced Training Manual. Biological Assessment Preparation for
1557 Transportation Projects. September 2005.
1558
1559 WSDOT. 2005c. Draft Fisheries and Aquatic Resources Discipline Report, Renton Nickel
1560 Improvement Project. July 2005.
1561
Biological Assessment 51 January 2006
Springbrook Creek Wetland and Habitat Mitigation Bank