HomeMy WebLinkAboutRS_South_Boeing_StreamHabitat_Narrative_240129_v1.pdf
STANDARD STREAM STUDY/HABITAT DATA REPORT
Boeing Renton South Bridge Seismic Retrofit
Renton, Washington
Prepared for
City of Renton
Renton, Washington
January 2024
Prepared by
WSP USA
1001 Fourth Avenue, Suite 3100
Seattle, Washington 98154
31405867.128
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page ii of iii
STANDARD STREAM STUDY/HABITAT DATA REPORT
BOEING RENTON SOUTH BRIDGE SEISMIC RETROFIT
RENTON, WASHINGTON
TABLE OF CONTENTS
SECTION PAGE
1.0 INTRODUCTION ............................................................................................................... 1
2.0 PROJECT DESCRIPTION ................................................................................................ 1
3.0 PURPOSE (REQUIREMENTS FOR SHORELINE EXEMPTION) .................................... 1
4.0 STANDARD STREAM STUDY NARRATIVE ................................................................... 2
4.1 Stream Classification ............................................................................................. 2
4.2 Vegetative Cover ................................................................................................... 2
4.3 Ecological Function ............................................................................................... 3
4.4 Fish and Wildlife .................................................................................................... 4
4.4.1 Mammals ................................................................................................... 4
4.4.2 Birds .......................................................................................................... 4
4.4.3 Amphibians and Reptiles ........................................................................... 5
4.4.4 Fish ............................................................................................................ 6
4.5 Measures to Protect Trees and Vegetation ........................................................... 7
4.6 No Net Loss of Ecological Function ...................................................................... 7
5.0 HABITAT DATA REPORT ............................................................................................... 8
5.1 Habitat Diversity .................................................................................................... 8
5.2 Migration Corridors ................................................................................................ 9
5.3 Species and Cover Types ..................................................................................... 9
5.4 Identification of Disturbed Areas............................................................................ 9
5.5 Existing Habitat Values and Functions ................................................................ 10
5.5.1 Temperature ............................................................................................ 10
5.5.2 Water Quality ........................................................................................... 11
5.5.3 Reach Sinuosity ....................................................................................... 11
5.5.4 Vegetative Conditions .............................................................................. 11
5.5.5 Floodplain Conditions .............................................................................. 11
5.5.6 Habitat Values and Functions at the Project Site .................................... 12
5.6 Habitat Alterations and Impacts and Proposed Habitat Management Program .. 12
6.0 REFERENCES ................................................................................................................ 13
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page iii of iii
LIST OF TABLES
Table 1. Small Mammals Reported to Occur along the Lower Cedar River1 ................................ 4
Table 2. Birds Reported to Occur along the Lower Cedar River1 ................................................. 5
Table 3. Amphibians Reported to Occur along the Lower Cedar River1 ....................................... 6
Table 4. Reptiles Occurring Along the Lower Cedar River1 .......................................................... 6
Table 5. Non-native Fish Species Introduced into the Lake Washington/Lake Union
System1 ............................................................................................................................. 7
Table 6. Mean Monthly Water Temperatures in the LCR at Renton 1992 through 2022 ............ 10
Table 7. Aquatic Life Temperature Criteria in Freshwater .......................................................... 11
LIST OF APPENDICES
Appendix A - Drawings
Appendix B - Photos
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 1 of 13
1.0 INTRODUCTION
The Boeing Company (Boeing) proposes a seismic retrofit to the South Bridge at the
Boeing Renton plant in Renton, Washington. The Boeing Renton South Bridge Seismic
Retrofit (project) will retrofit the Boeing South Bridge in order to increase the
structure’s capability of resisting modern seismic design forces. The bridge foundations
will be extended north and south at each end of the bridge and new steel micropiles will
be driven as part of the work.
Project activities are located within the 200-foot shoreline setback. As part of permit
applications for facility improvements adjacent to shorelines, the Renton Municipal
Code (RMC) requires a standard stream or lake study and a habitat data report to
document existing conditions and describe measures to be taken to protect shoreline
resources. This Standard Stream Study/Habitat Data Report has been prepared to meet
the requirements detailed in the RMC.
2.0 PROJECT DESCRIPTION
The project consists of retrofitting the South Bridge at the Boeing Renton plant with
seismic upgrades including two seismic retrofit structures, one at each abutment.
Project activities are located within the 200-foot shoreline setback. The retrofit
structures will consist of new steel micropiles, a pile cap, abutment bolsters, and
approach slabs. Approximately 5,744 square feet of existing impervious paved area will
be removed and replaced in-kind by the project. Approximately 3,582 square feet of
grass, exposed soil and landscaping will be temporarily impacted by clearing and
grubbing during construction and will be enhanced and replanted with native vegetation
and seed mixes resulting in a net environmental uplift.
Project drawings are included in Appendix A.
3.0 PURPOSE (REQUIREMENTS FOR SHORELINE EXEMPTION)
Under the RMC 4-9-190C1 (Shoreline Exemption Process), the City of Renton requires
the following environmental reports to be included with Boeing’s permit application
submittal for the proposed project:
· Standard Stream or Lake Study: A report shall be prepared by a qualified biologist,
including a narrative report describing the stream or lake classification, vegetative
cover of the site, ecological functions, observed or reported fish and wildlife,
measures to protect trees and vegetation, and demonstrate the proposal meets the
criteria of no net loss of ecological functions as described in RMC 4-3-090D2.
· Habitat Data Report: A narrative report shall be prepared to accompany the site
plan, which describes the layers, diversity, and variety of habitat found on the site;
the location of any migration or movement corridors; species expected to be found;
identification of any disturbed areas; summary of existing habitat functions and
values; and summary of proposed habitat alterations and impacts and proposed
habitat management program.
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 2 of 13
4.0 STANDARD STREAM STUDY NARRATIVE
This section presents the standard stream study narrative, providing information about
existing habitat conditions and functions of the lower Cedar River (LCR) adjacent to
the proposed project site.
4.1 STREAM CLASSIFICATION
According to RMC 4-3-050Q4 (City of Renton Water Class Map), the LCR in the
vicinity of the project site is Class 1 water.
4.2 VEGETATIVE COVER
WSP personnel conducted a site survey on January 19, 2024 to assess habitat
conditions and vegetative cover along the LCR shoreline adjacent to and within
100 feet upstream and downstream of the proposed project site. The project site is
defined as the South Bridge and those areas within the 200-foot shoreline setback
adjacent to the LCR. The Boeing facilities and Renton Municipal Airport in the vicinity
of the project that are within the 200-foot shoreline setback consist primarily of
concrete and asphalt surfaces.
The riparian zone along the east bank of the LCR adjacent to and within 100 feet
upstream and downstream of the project site comprises an approximately 70-foot-wide
vegetated band. The vegetated band is bisected by an approximate 9-foot-wide asphalt
path (Cedar River Trail) that runs in the upland parallel to the river. Existing
landscaping is present within 50 feet to the north and south of the bridge and is
predominantly mulched with minimal ground cover. Landscaped vegetation includes
snowberry (Symphoricarpos albus), horsetail (Equisetum hyemale), western swordfern
(Polystichum munitum), and Oregon grape (Mahonia aquifolium). Adjacent to the
landscaped area, the next 50 feet consist of a narrow strip approximately 16 to 22 feet
wide adjacent to the river of primarily planted and volunteer native trees, shrubs, and
herbaceous groundcover, with some non-native trees and shrubs present. Vegetation
observed on January 19, 2024 is described further below.
The riparian zone along the west bank of the LCR adjacent to and within 100 feet
upstream and downstream of the project site comprises an approximately 40-foot-wide
vegetated band. Approximately 50 percent of this band is grass ground cover or
exposed soil. To the west of the vegetated band is a concrete barrier wall and the
Renton Municipal Airport.
Representative photos of the riparian habitat adjacent to the project site are provided in
Appendix B.
Native trees and shrubs adjacent to the site include snowberry (Symphoricarpos albus),
Nootka rose (Rosa nutkana), red osier dogwood (Cornus sericea), western swordfern
(Polystichum munitum), Indian plum (Oemleria cerasiformis), Oregon grape (Mahonia
aquifolium), horsetail (Equisetum hyemale), Douglas fir (Pseudotsuga menziesii), shore
pine (Pinus contorta contorta), spruce (Abies sp.), and alder (Alnus rubra). Non-native
plants were observed primarily along the east banks Cedar River Trail and include red
maple (Acer rubrum), horse chestnut (Aesculus hippocastanum), and low cotoneaster
(Cotoneaster sp.). A small patch of common reed (Phragmites australis) was observed
on the west bank north of the project site. Approximately 25 percent of the upland area
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 3 of 13
on the east bank and approximately 60 percent of the upland area on the west bank
within 100 feet upstream and downstream of the project site are grass/lawn.
The limited riparian vegetation along the east and west banks adjacent to the project
site and the highly developed shorelines along both banks of the LCR (50 percent
grass/lawn cover, concrete barriers, and paved impervious surfaces) severely limit
habitat availability and use by multiple plant and animal species within the 200-foot
shoreline setback.
In addition to the Washington Department of Fish and Wildlife’s Priority Habitat and
Species database, a search of the Washington Department of Natural Resources’
Natural Heritage Program online mapper (https://www.dnr.wa.gov/NHPdata) was
performed. No rare plants and rare/high-quality ecosystems were identified in the
vicinity of the project site.
Critical wildlife species occurring at the project site include the salmonids identified in
Section 3.4, Fish and Wildlife.
4.3 ECOLOGICAL FUNCTION
Riparian habitats have important ecological functions other than providing habitat for
birds and other wildlife. Healthy riparian vegetation protects banks from erosion,
influences in-channel aquatic habitats, maintains favorable water temperature for fish
through shading, filters runoff, and provides nutrients. Riparian vegetation increases
habitat complexity, creates off-channel habitat, and can protect against scour during
severe storm events. Riparian habitats link upland and aquatic habitats. Upland habitats
have a critical role in watershed function and affect riparian and aquatic habitats,
particularly in drier, low-elevation sites.
The riparian zone along the east bank of the LCR adjacent to and within 100 feet
upstream and downstream of the project site located on the east side of the LCR is a
relatively narrow vegetated band consisting of trees, shrubs, and manicured lawn. A
paved pedestrian trail occurs in this area as well. Several invasive species also were
observed, as discussed in Section 3.2, Vegetative Cover.
The riparian zone along the west bank of the LCR adjacent to and 100 feet upstream
and downstream of the project site located on the west side of the LCR consists of trees,
shrubs, and grass within 40 feet of the LCR, and impervious paved surface within the
remaining riparian buffer.
The primary ecological functions provided by riparian vegetation along the east and
west banks of the LCR within 100 feet upstream and downstream of the project site
include:
· Nesting and foraging habitat for birds and small mammals
· Input of terrestrial insects from overhanging vegetation
· Input of allochthonous organic matter (via leaf fall)
· Limited erosion control
· Limited habitat complexity
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 4 of 13
The LCR is a man-made channel created in 1912 when the river was diverted as a
tributary to the former Black River directly to Lake Washington. The LCR is
channelized and substantially altered, so that there is very limited riparian area to
provide all the potential ecological functions of an unaltered habitat. Riparian
vegetation provides very little, if any, shading to the LCR because of the dominance of
small shrubs and the lack of large trees. Both banks of the river in the project area are
contained within levees and/or flood-control walls, so there is no potential for the
creation of off-channel habitat. Because of extensive development along both banks of
the river in the project area, there is little, if any, transition between riparian and upland
habitats.
4.4 FISH AND WILDLIFE
This section addresses fish and wildlife species that may use the LCR in the vicinity of
the project site.
4.4.1 Mammals
An Eastern cottontail rabbit (Sylvilagus floridanus) was observed during the site visit.
Given the level of development and paved surface area in the project area, it is likely
that only small mammals, such as beaver, squirrels, mice, rats, voles, moles, raccoons,
opossums, muskrats, and river otters, use the riparian areas along the LCR shoreline
adjacent to and within 100 feet upstream and downstream of the project areas. While
conducting small mammal surveys in a wetland along the LCR, Klaus Richter and
Amanda Azous (Azous and Horner, 1997) reported 13 species of mammals (Table 1).
These, as well as other small mammals common to the Puget lowlands, may occur
along the LCR adjacent to the project site.
Table 1. Small Mammals Reported to Occur along the Lower Cedar River1
Common Name Scientific Name Common Name Scientific Name
Creeping vole Microtus oregoni Montane shrew Sorex monticolus
Deer mouse Peromyscus
maniculatus
Shrew-mole Neurotrichus gibbsii
Ermine Mustela ermine Southern red-backed
vole
Clethryonomys gapperi
Forest deer mouse Peromyscus oreas Townsend’s chipmunk Tamias townsendii
Long-tailed vole Microtus longicaudus Trowbridge’s shrew Sorex trowbridgei
Marsh shrew Sorex bendirei Vagrant shrew Sorex vagrans
Masked shrew Sorex cinereus
1Source: Azous and Horner, 1997.
4.4.2 Birds
Several bird species were observed during the site visit, including American crow
(Corvus brachyrhynchos), an immature gull species (Larus spp.), and several
unidentified songbird species. Richter and Azous (Azous and Horner, 1997) conducted
bird surveys in a wetland of the LCR between late May and mid-June in 1988, 1989,
1991, 1992, and 1995 to determine distribution and relative abundance. They reported
58 species of birds (Table 2). It is likely that these, as well as other species of birds
common to the Puget lowlands, nest or forage in the project vicinity.
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 5 of 13
Table 2. Birds Reported to Occur along the Lower Cedar River1
Common Name Scientific Name Common Name Scientific Name
American crow Corvus brachyrhynchos Northern pygmy owl Glaucidium gnoma
American goldfinch Carduelis tristis Orange -crowned
warbler
Vermivora celata
American robin Turdus migratorius Pine siskin Carduelis pinus
Black-capped chickadee Parus atricapillus Pacific-slope flycatcher Empidonax difficilis
Belted kingfisher Ceryle alcyon Purple finch Carpodacus purpureus
Bewick’s wren Thryomanes bewickii Red-breasted nuthatch Sitta Canadensis
Brown-headed cowbird Molothrus ater Red-breasted sapsucker Sphyrapicus ruber
Black-headed grosbeak Pheucticus
melanocephalus
Red crossbill Loxia curvirostra
Brewer’s blackbird Euphagus
cyanocephalus
Red-eyed vireo Vireo olivaceus
Brown creeper Certhia Americana Rufous-sided towhee Pipilo erythrophthalmus
Black-throated gray
warbler
Dendroica nigrescens Ruffed grouse Bonasa umbellus
Bushtit Psaltriparus minimus Ruby-crowned kinglet Regulus calendula
Chestnut-backed
chickadee
Parus rufescens Red-winged blackbird Agelaius phoeniceus
Cedar waxwing Bombycilla cedrorum Sora Porzana Carolina
Cooper’s hawk Accipiter cooperii Song sparrow Melospiza melodia
Common raven Corvus corax Sharp-shinned hawk Accipiter striatus
Common yellow throat Geothlypis trichas Steller’s jay Cyanocitta stelleri
Dark-eyed junco Junco hyemalis Swainson’s thrush Catharus ustulatus
Downy woodpecker Picoides pubescens Townsend’s warbler Setophaga townsendi
European starling Sturnus vulgaris Vaux’s swift Chaetura vauxi
Evening grosbeak Coccothraustes
vespertinus
Violet-green swallow Tachycineta thalassina
Fox sparrow Passerella iliaca Virginia rail Rallus limicola
Great blue heron Ardea herodias Warbling vireo Vireo gilvus
Golden-crowned kinglet Regulus satrapa Western tanger Piranga ludoviciana
Hairy woodpecker Picoides villosus Willow flycatcher Empidonax traillii
Hermit thrush Catharus guttatus Wilson’s warbler Cardellina pusilla
Marsh wren Cistothorus palustris Winter wren Troglodytes hiemalis
MacGillivray’s warbler Geothlypis tolmiei Wood duck Aix sponsa
Northern flicker Colaptes auratus Yellow warbler Dendroica petechia
1Source: Azous and Horner, 1997.
4.4.3 Amphibians and Reptiles
No amphibians or reptiles were observed during the site visit; however, it is likely that
amphibian (e.g., anurans) and reptile species (e.g., turtles) found in the Lake
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 6 of 13
Washington basin may use the areas within the site vicinity. Richter and Azous (Azous
and Horner, 1997) reported the occurrence of six amphibian species in the LCR, as
listed in Table 3.
Table 3. Amphibians Reported to Occur along the Lower Cedar River1
Common Name Scientific Name Common Name Scientific Name
Ensatina Ensatina eschscholtzii Pacific tree frog Pseudoacris regilla
Long-toed salamander Ambystoma
macrodactylus
Red-legged frog Rana aurora
Northwestern
salamander
A. gracile Western red-backed
salamander
Plethodon vehiculum
1Source: Azous and Horner, 1997.
No information was located listing reptile species occurring along the LCR in the
project vicinity; however, reptiles listed for King County (King County, 2008) that
could occur in the project vicinity are listed in Table 4.
Table 4. Reptiles Occurring Along the Lower Cedar River1
Common Name Scientific Name Common Name Scientific Name
Common garter snake Thamnophis sirtalis Rubber boa Charina bottae
Northern alligator lizard Elgaria coerulea Slider Trachemys scripta
Northwestern garter
snake
T. ordinoides Western fence lizard Sceloporus
occidentalis
Painted turtle Chrysemys picta Western terrestrial
garter snake
T. elegans
1Source: King County, 2008.
4.4.4 Fish
No fish were observed in the LCR adjacent to the project site during the site visit. The
Lake Washington system, including the LCR adjacent to the project site, hosts many
fish species, including five salmonid species: Chinook salmon (Oncorhynchus
tshawytscha), coho salmon (O. kisutch), sockeye/kokanee salmon (O. nerka), coastal
cutthroat trout (O. clarkii), and steelhead/rainbow trout (O. mykiss). Anadromous forms
of each of these species use the Cedar River system as migratory, forage, nursery, and
spawning habitat, so individuals are present in the river both as adults during
migrations to spawning grounds and as juveniles (Kerwin, 2001). All these species
occur seasonally in the LCR adjacent to the project site. Additionally, there have been
isolated reports of coastal/Puget Sound bull trout (Salvelinus confluentus) occurring in
the Lake Washington system; however, it is believed that few bull trout occur in the
Lake Washington system, if they occur at all. Puget Sound Chinook salmon, Puget
Sound steelhead trout, and bull trout are federally listed species under the Endangered
Species Act (ESA).
Species endemic to the Lake Washington system include the northern pike minnow
(Ptychocheilus oregonensis), peamouth (Mylocheilus caurinus), sculpins (Cottus spp.),
and longfin smelt (Spirinchus thaleichthys) (Weitkamp et al., 2000; Wydoski and
Whitney, 2003). Twenty-four non-native fish species (Table 5) have been identified in
the Lake Washington/Lake Union system. A number of these species are now believed
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 7 of 13
to be no longer present in the system. Some of these species are known to prey on
juvenile salmon (e.g., smallmouth bass) while others are potential competitors with
juvenile salmonids for food (Kerwin, 2001).
Table 5. Non-native Fish Species Introduced into
the Lake Washington/Lake Union System1
Common Name Scientific Name Common Name Scientific Name
American shad Alosa sapidissima Goldfish Carassius auratus
Atlantic salmon Salmo salar Grass carp Ctenopharengodon
idella
Black bullhead Ictalurus melas Lake Trout Salvelinus namaycush
Black crappie Pomoxis
nigromaculatus
Lake whitefish Coregonus
clupeaformis
Bluegill Lepomis macrocheilus Largemouth bass Micropterus salmoides
Brook trout Salvelinus fontinalis Pumpkinseed sunfish Lepomis gibbosus
Brown bullhead Ictalurus nebulosus Smallmouth bass Micropterus dolomieui
Brown trout Salmo trutta Tench Tinca tinca
Channel catfish Ictalurus punctatus Warmouth Lepomis gulosus
Cherry salmon Oncorhynchus masou Weather loach Misgurnus
angillicaudatus
Common carp Cyprinus carpio White crappie Pomoxis annularis
Fathead minnow Pimephales notatus Yellow perch Perca flavescens
1Source: Kerwin, 2001.
4.5 MEASURES TO PROTECT TREES AND VEGETATION
The proposed project footprint is approximately 9,326 square feet within the 200-foot
shoreline setback on the banks of the LCR. Of this, approximately 5,744 square feet is
existing impervious paved area that will remain paved impervious. The remaining
3,582 square feet is approximately 50 percent grass and exposed soil on the west bank
and is landscaped on the east bank with mulch and minimal ground cover. This area of
the buffer will be temporarily impacted by clearing and grubbing during construction
and will be enhanced and replanted with native vegetation and seed mixes resulting in a
net environmental uplift.
Temporary erosion and sediment control, including straw waddles and silt fence, will
be installed to prevent erosive conditions during construction and reduce impact to the
existing adjacent vegetation and habitat.
4.6 NO NET LOSS OF ECOLOGICAL FUNCTION
The project will result in no net loss of ecological function in the riparian zone of the
LCR adjacent to and 100 feet upstream and downstream of the project site. There will
be no change in impervious surface area within the shoreline setback. The existing
habitat condition on the site is approximately 50 percent grass and exposed soil on the
west bank and is landscaped on the east bank with mulch and minimal ground cover.
The west bank will be replanted and stabilized with 55 percent riverbank mix and
45 percent hydroseed mix. The east bank will be replanted with a mix of subalpine
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 8 of 13
spiraea (spiraea densiflora), red osier dogwood (cornus sericea), pacific ninebark
(physocarpus capitatus), nootka rose (rosa nutkana), and Oregon grape (mahonia
aquifolium compacta) and will result in reduction of open mulched area.
Under the bridge and within the bridge footprint, each bank is stabilized above the
ordinary high water mark (OHWM) with existing rip rap fill. The project will replace
this with light loose rip rap within the same footprint.
The concept of “no net loss” means to create, restore, and/or enhance an area so that
there is no reduction to total acreage and/or function. The project will restore the buffer
area temporarily impacted and will result in no reduction of vegetated area. The buffer
area temporarily impacted will be replanted with native vegetation and seed mixes that
will improve LCR habitat value and result in a net environmental uplift. The river bank
under the bridge will be stabilized with rip rap within the existing rip rap and bridge
footprint.
5.0 HABITAT DATA REPORT
This section presents the habitat data report, providing information about pertinent
habitat and ecological function at the proposed project site.
5.1 HABITAT DIVERSITY
The LCR downstream of Interstate 405 (approximately 1.6 miles) is an artificial
channel created early in the twentieth century and is completely constrained between
levees and revetments. This reach was regularly dredged to prevent flooding from the
time of its completion in 1912 until the mid-1970s. Portions of the reach were again
dredged in 1999 for the first time since the mid-1970s. Flood control dredging was
conducted during the summer of 2016. In-stream habitat in the reach is almost entirely
glide, with little habitat complexity. Land uses prevent floodplain connectivity and have
eliminated the potential for reconnection with a natural floodplain or the establishment
of a riparian corridor. Channelization and existing land uses also prevent significant
large woody debris (LWD) from accumulating in the channel. The reach is also very
low gradient and depositional, and the substrates have high levels of fine sediments
(U.S. Army Corps of Engineers [USACE], 2004).
The shoreline along the LCR adjacent to the project site consists of developed property
belonging to Boeing and the City of Renton. With realignment of the Cedar River into
Lake Washington in 1912, the zone of sediment deposition was localized through the
City of Renton (Perkins, 1994). The vast majority, if not all, of the non-suspendable
sediment load is now deposited along this reach because Lake Washington lies at the
river’s mouth. With the path of the river fixed by armored banks, progressive infilling
of the channel resulted. Sediment is continually deposited in the downstream 2 miles of
the river and in an enlarging delta in Lake Washington.
Aquatic habitat within the LCR adjacent to the project site consists of a low relief
benthic habitat composed of small cobbles with some gravel and no boulders. LWD in
the stretch of the LCR adjacent to the project site is extremely limited. River discharged
at the time of the site visit on January 19, 2024 was approximately 504 cubic feet per
second (U.S. Geological Survey [USGS], 2024). Channelization of the LCR has
eliminated meanders within the lower river, such that the lower 1.6 miles of river
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 9 of 13
consists of a uniform glide habitat with a nearly complete absence of riffles and pools.
Habitat diversity along the LCR adjacent to the project site is extremely limited.
5.2 MIGRATION CORRIDORS
A search of the Washington Department of Fish and Wildlife’s Priority Habitat and
Species database (http://wdfw.wa.gov/mapping/phs/) identified five salmonid species
that use the LCR as a migration corridor:
· Chinook salmon
· Coho salmon
· Sockeye salmon
· Steelhead and rainbow trout
· Coastal cutthroat trout
Two of the above species, Puget Sound Chinook salmon and Puget Sound steelhead
trout, are listed as threatened under the ESA.
Bull trout, a member of the char family, may also be found in the LCR and is also listed
as threatened under the ESA. Population status information and extent of use of this
area are currently unknown. Adult and subadult size individuals have been observed
infrequently in the LCR (below Cedar Falls), Lake Washington, and at the Locks.
5.3 SPECIES AND COVER TYPES
The almost complete absence of riparian vegetation along the west bank of the LCR
within the 200-foot shoreline setback and the relatively narrow zone of riparian
vegetation along the east bank within the 200-foot shoreline setback adjacent to the
project site and the highly developed nature of the adjacent upland along both banks of
the LCR severely limit habitat availability and use by multiple plant and animal
species. The concrete flood-control wall on the west bank of the LCR adjacent to the
project site severely limits the width of the riparian zone and eliminates the transition
zone from riparian to terrestrial habitats.
Typical plant and animal assemblages and associations that would be expected along
the riparian corridor of the LCR are, for the most part, very limited or absent along the
stretch of the LCR adjacent to the proposed project site.
A search of the Washington Department of Natural Resources’ Natural Heritage
Program online database did not identify any plant or terrestrial animal species of
special concern in the vicinity of the project site
(http://www.dnr.wa.gov/ResearchScience/HowTo/ConservationRestoration/Pages/
amp_nh_data_order.aspx).
Critical wildlife species occurring at the project site include those salmonids identified
in Section 4.2 above.
5.4 IDENTIFICATION OF DISTURBED AREAS
The entire project area is highly developed and disturbed. As stated in Section 4.1,
Habitat Diversity, the lower 1.6 miles of the LCR is an artificially created channel with
extensive development along both banks. The majority of the 200-foot shoreline
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 10 of 13
setback and adjacent upland within the project vicinity is impervious asphalt and/or
cement with various structures, such as office buildings and aircraft hangers.
5.5 EXISTING HABITAT VALUES AND FUNCTIONS
The LCR adjacent to the project site has very limited habitat value and is low
functioning. A combination of two habitat assessment methods was used to provide a
qualitative assessment of the existing habitat values and functions. These habitat
assessment methods were the U.S. Environmental Protection Agency’s (EPA) Rapid
Bioassessment Protocols for Use in Wadeable Streams and Rivers (Barbour et al.,
1999) and the U.S. Forest Service’s Stream Inventory Handbook: Levels I and II
(USFS, 2012). Both methods incorporate the use of physicochemical and biological
parameters to assess habitat value and functionality. The EPA’s Rapid Bioassessment
Protocols incorporate both benthic invertebrate and fish assemblages’ data in evaluating
habitat value and function. For the purposes of this project, neither benthic invertebrate
nor fish assemblage data were collected as part of the evaluation process due to the
necessity of applying for and receiving the necessary permits to gather such data. The
habitat assessment is based on physicochemical conditions observed at the project site:
· Temperature
· Water quality
· Reach sinuosity
· Vegetative conditions of the stream banks and the riparian zone
· Condition of the floodplain (e.g., accessibility from the bank, overflow, and size)
Each of the above parameters is discussed below.
5.5.1 Temperature
Mean monthly water temperatures in degrees Celsius in the LCR at Renton for the
period of March 1992 through September 2022 (USGS, 2024) are listed in Table 6.
Table 6. Mean Monthly Water Temperatures in the LCR at Renton 1992 through 2022
Month Mean of Monthly
Temperature °C
January 6.1
February 6.4
March 7.6
April 9.5
May 11.6
June 13.5
July 15.8
August 16.1
September 13.9
October 11.0
November 8.2
December 6.4
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 11 of 13
The warmest water temperatures occur during the months of June, July, August, and
September; however, even the highest mean monthly temperatures are compliant with
Washington State aquatic life temperature criteria (WAC 173-201A Table 200 (1)(c))
listed in Table 7, with the exception of the char spawning and rearing and core summer
salmonoid habitat. Char (e.g., bull trout) do not spawn in the LCR, and it is highly
unlikely that they use the LCR as rearing habitat.
Table 7. Aquatic Life Temperature Criteria in Freshwater
Category Highest 7-DADMax °C
Char Spawning and Rearing 12.0
Core Summer Salmonoid Habitat 16.0
Salmonoid Spawning, Rearing, and Migration 17.5
Salmonoid Rearing and Migration Only 17.5
Nonanadromous Interior Redband Trout 18.0
Indigenous Warm Water Species 20.0
Note: 7-DADMAX = 7-day average of the daily maximum temperatures
5.5.2 Water Quality
No site-specific water quality data were found for the project site; however, water
quality monitoring has been conducted in south Lake Washington by the Washington
State Department of Ecology. Washington State’s Water Quality Assessment (303[d]
and 305[b] Report) (Ecology, 2018) identified exceedances of water quality standards
for temperature, pH, dissolved oxygen, and fecal coliforms in the LCR. No chemical
exceedances of state water quality criteria were identified for the LCR adjacent to the
project site.
5.5.3 Reach Sinuosity
As discussed above, the lower 1.6 miles of the LCR are channelized and much of the
shoreline on both banks is restrained by bulkheads. There is no sinuosity within the
entire 1.6 miles of the LCR. Stream sinuosity can provide increased habitat complexity
through the creation of pools, riffles, and glides, as well as the creation of off-channel
habitat.
5.5.4 Vegetative Conditions
As described previously, riparian vegetation is sparse along both banks of the LCR
within 100 feet of the project site. As such, habitat diversity and functionality along this
reach of the LCR is severely limited.
5.5.5 Floodplain Conditions
The LCR is an artificially created channel confined by levees and bulkheads on each
bank. Except in extreme discharge conditions, the LCR has very little connectivity with
its floodplain and virtually no potential for formation of off-channel habitat within the
floodplain. Because of the low gradient of the LCR, it functions as a sediment
depositional zone. The City of Renton and the USACE periodically dredges the LCR
for flood control purposes. Flood-control dredging was conducted during the summer
of 2016.
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 12 of 13
5.5.6 Habitat Values and Functions at the Project Site
A qualitative assessment of the LCR adjacent to the project site indicates that it
provides very low habitat value and function due primarily to the sparse riparian
vegetation and habitat complexity.
5.6 HABITAT ALTERATIONS AND IMPACTS AND PROPOSED HABITAT
MANAGEMENT PROGRAM
The project will not involve any in-water components or work below the OHWM.
Approximately 3,582 square feet of buffer consisting of existing grass and exposed soil
on the west bank and landscaping on the east bank will be temporarily impacted by
clearing and grubbing during construction and will be enhanced and replanted with
native vegetation and seed mixes. The project will restore the buffer area temporarily
impacted and will result in no reduction of vegetated area.
Temporary erosion and sediment control, including straw waddles and silt fence, will
be installed to prevent erosive conditions during construction and reduce impact to the
existing adjacent vegetation and habitat.
The buffer area temporarily impacted will be replanted with native vegetation and seed
mixes that will improve LCR habitat value and result in a net environmental uplift. No
habitat management or mitigation programs are required for the proposed tasks and
none are proposed.
Boeing Renton South Bridge Seismic Retrofit WSP USA, 31405867.128
Standard Stream Study/Habitat Data Report January 2024
Renton, Washington Page 13 of 13
6.0 REFERENCES
Azous, A.L. and Horner, R.R. (eds.) 1997. Wetlands and Urbanization – Implications for the
Future, Final Report of the Puget Sound Wetlands and Stormwater Management
Research Program. Washington State Department of Ecology, Olympia, King County
Water and Land Resources Division, Seattle, Washington, and University of Washington,
Seattle, Washington. Accessed at https://your.kingcounty.gov/dnrp/library/archive-
documents/wlr/wetlands-urbanization-report/wet-rept.pdf. January 16, 2024.
Barbour, M.T., Gerritsen, J., Snyder, B.C., and Stribling, J.B. 1999. Rapid Bioassessment
Protocols for Use in Streams and Wadeable Rivers. U.S. Environmental Protection
Agency, Office of Water, EPA 841-B-99-002, Washington, DC.
Kerwin, J. 2001. Salmon and Steelhead Habitat Limiting Factors Report for the Cedar-
Sammamish Basin (Water Resource Inventory Area 8). Washington Conservation
Commission, Olympia, Washington. Accessed at:
https://www.govlink.org/watersheds/8/pdf/WRIA_8_LimFactors_Summary.pdf. January
16, 2024.
King County. 2008. King County Biodiversity Report 2008. King County, Seattle, Washington.
Accessed at:
http://www.kingcounty.gov/environment/animalsAndPlants/biodiversity/king-county-
biodiversity-report.aspx. January 16, 2024.
Perkins, S.J. 1994. The shrinking Cedar River – channel changes following flow regime
regulation and bank armoring, in Proceedings of Effects of Human-Induced Changes on
Hydrologic Systems. American Water Resources Association 1994 Annual Summer
Symposium, p. 649-658.
U.S. Army Corps of Engineers (USACE). 2004. Cedar River at Renton Flood Damage
Reduction Operation and Maintenance Manual – Cedar River Section 205 (Renton,
Washington). U.S. Army Corps of Engineers, Seattle District, Seattle, Washington.
U.S. Geological Survey (USGS). 2024. USGS Surface-Water Monthly Statistics for
Washington – USGS 12119000 Cedar River at Renton. Department of the Interior,
USGS, National Water Information System, Accessed at:
https://nwis.waterdata.usgs.gov/wa/nwis/uv/?cb_all_00010_00060_00065=on&cb_00010
=on&cb_00060=on&cb_00065=on&format=gif_default&period=&begin_date=2013-05-
27&end_date=2016-12-31&site_no=12119000. January 16, 2024.
Washington State Department of Ecology (Ecology). 2018. Washington State’s 2018 Water
Quality Assessment (303[d] & 305[b] Report). Ecology. Accessed at:
https://geo.wa.gov/datasets/waecy::water-quality-assessment-305b-report-current/about.
January 16, 2024.
Weitkamp, D.E., Ruggerone, G.T., Sacha, L., Howell, J., and Bachen, B. 2000. Factors
Affecting Chinook Populations – Background Report. City of Seattle, Seattle,
Washington.
Wydoski, R.S., and Whitney, R.R. 2003. Inland Fishes of Washington. American Fisheries
Society, Bethesda, Maryland, and University of Washington Press, Seattle.
APPENDIX A
DRAWINGS
COVER SHEET G01
BOEING RENTON FACTORY
SHARED SERVICES GROUP
RENTON, WASHINGTON 98057
NORTH 6TH STREET
THE COMPANY
VICINITY MAP CODE SUMMARY DRAWING INDEX
CIVIL
STRUCTURAL
LANDSCAPING
SOUTH BRIDGE SEISMIC RETROFIT
PROJECT WORK
LOCATION
·
·PRELIMINARY - NOT FOR CONSTRUCTION
GENERAL NOTES G02 PRELIMINARY - NOT FOR CONSTRUCTION
SITE PLAN G03 PRELIMINARY - NOT FOR CONSTRUCTION
BRIDGE PLAN AND ELEVATION S01 PRELIMINARY - NOT FOR CONSTRUCTION
BUILDING 4-100
CONSTRUCTION SEQUENCE
S02 S--
ABUTMENT RETROFIT
PLAN AND ELEVATION
S03 PRELIMINARY - NOT FOR CONSTRUCTION
ABUTMENT RETROFIT DETAILS S04 PRELIMINARY - NOT FOR CONSTRUCTION
PILE CAP DETAILS 1 S05 S--
PILE CAP DETAILS 2 S06 S--
WINGWALL DETAILS S07 S--
·
·
·
MICROPILE DETAILS S08 PRELIMINARY - NOT FOR CONSTRUCTION
APPROACH SLAB DETAILS S09 S--
MISCELLANEOUS DETAILS S10 S--
1
SCALE: 1" =
0
FT
10'
10 20
SITE PREP AND TESC PLAN C01 S--
LEGEND:
STRAW WATTLES PER CITY OF
RENTON STD PLAN 213.40
SAWCUT
REMOVE PIPE
SILT FENCE PER CITY OF
RENTON STD PLAN 214.00
CLEAR AND GRUB LINE
FULL DEPTH PAVEMENT
REMOVAL
CLEAR AND GRUB
GENERAL NOTES:
1.LOCATIONS OF EXISTING SUBSURFACE
UTILITIES ARE APPROXIMATE
CONTRACTOR TO VERIFY
CONSTRUCTION NOTES:
CATCH BASIN INSERT PER CITY OF RENTON
STD PLAN 216.30
1.APPROVAL OF THIS EROSION AND SEDIMENTATION CONTROL (TESC) PLAN DOES NOT CONSTITUTE AN APPROVAL OF
PERMANENT ROAD OR DRAINAGE DESIGN (E.G., SIZE AND LOCATION OR ROADS, PIPES, RESTRICTORS, CHANNELS, RETENTION
FACILITIES, UTILITIES, ETC.).
2.THE IMPLEMENTATION OF THESE ESC PLANS AND THE CONSTRUCTION, MAINTENANCE, REPLACEMENT, AND UPGRADING OF
THESE ESC FACILITIES IS THE RESPONSIBILITY OF THE APPLICANT/ESC SUPERVISOR UNTIL ALL CONSTRUCTION IS
APPROVED.
3.THE BOUNDARIES OF THE CLEARING LIMITS SHOWN ON THIS PLAN SHALL BE CLEARLY FLAGGED BY SURVEY TAPE OR
FENCING, IF REQUIRED, PRIOR TO CONSTRUCTION (SWDM APPENDIX D). DURING THE CONSTRUCTION PERIOD, NO
DISTURBANCE BEYOND THE CLEARING LIMITS SHALL BE PERMITTED. THE CLEARING LIMITS SHALL BE MAINTAINED BY THE
APPLICANT/ESC SUPERVISOR FOR THE DURATION OF CONSTRUCTION.
4.STABILIZED CONSTRUCTION ENTRANCES SHALL BE INSTALLED AT THE BEGINNING OF CONSTRUCTION AND MAINTAINED FOR
THE DURATION OF THE PROJECT. ADDITIONAL MEASURES, SUCH AS CONSTRUCTED WHEEL WASH SYSTEMS OR WASH PADS,
MAY BE REQUIRED TO ENSURE THAT ALL PAVED AREAS ARE KEPT CLEAN AND TRACK OUT TO ROAD RIGHT OF WAY DOES NOT
OCCUR FOR THE DURATION OF THE PROJECT.
5.THE ESC FACILITIES SHOWN ON THIS PLAN MUST BE CONSTRUCTED PRIOR TO OR IN CONJUNCTION WITH ALL CLEARING AND
GRADING SO AS TO ENSURE THAT THE TRANSPORT OF SEDIMENT TO SURFACE WATERS, DRAINAGE SYSTEMS, FLOW
CONTROL BMP LOCATIONS (EXISTING AND PROPOSED), AND ADJACENT PROPERTIES IS MINIMIZED.
6.THE ESC FACILITIES SHOWN ON THIS PLAN ARE THE MINIMUM REQUIREMENTS FOR ANTICIPATED SITE CONDITIONS. DURING
THE CONSTRUCTION PERIOD, THESE ESC FACILITIES SHALL BE UPGRADED AS NEEDED FOR UNEXPECTED STORM EVENTS
AND MODIFIED TO ACCOUNT FOR CHANGING SITE CONDITIONS (E.G. ADDITIONAL COVER MEASURES, ADDITIONAL SUMP
PUMPS, RELOCATION OF DITCHES AND SILT FENCES, PERIMETER PROTECTION, ETC.) AS DIRECTED BY KING COUNTY.
7.THE ESC FACILITIES SHALL BE INSPECTED DAILY BY THE APPLICANT, ESC SUPERVISOR AND MAINTAINED TO ENSURE
CONTINUED PROPER FUNCTIONING. WRITTEN RECORDS SHALL BE KEPT OF WEEKLY REVIEWS OF THE ESC FACILITIES.
8.ANY AREAS OF EXPOSED SOILS, INCLUDING ROADWAY EMBANKMENTS THAT WILL NOT BE DISTURBED FOR TWO
CONSECUTIVE DAYS DURING THE WET SEASON OR SEVEN DAYS DURING THE DRY SEASON SHALL BE IMMEDIATELY
STABILIZED WITH THE APPROVED ESC METHODS (E.G., SEEDING, MULCHING, PLASTIC COVERING, ETC.).
9.ANY AREAS NEEDING ESC MEASURES THAT DO NOT REQUIRE IMMEDIATE ATTENTION SHALL BE ADDRESSED WITHIN SEVEN (7)
DAYS.
10. THE ESC FACILITIES ON INACTIVE SITES SHALL BE INSPECTED AND MAINTAINED A MINIMUM OF ONCE A MONTH DURING THE
DRY SEASON, BI-MONTHLY DURING THE WET SEASON, OR WITHIN TWENTY FOUR (24) HOURS FOLLOWING A STORM EVENT.
11.AT NO TIME SHALL MORE THAN ONE (1) FOOT OF SEDIMENT BE ALLOWED TO ACCUMULATE WITHIN A CATCH BASIN. ALL
CATCH BASINS AND CONVEYANCE LINES SHALL BE CLEANED PRIOR TO PAVING. THE CLEANING OPERATION SHALL NOT
FLUSH SEDIMENT-LADEN WATER INTO THE DOWNSTREAM SYSTEM.
12. ANY PERMANENT RETENTION/DETENTION FACILITY USED AS A TEMPORARY SETTLING BASIN SHALL BE MODIFIED WITH THE
NECESSARY EROSION CONTROL MEASURES AND SHALL PROVIDE ADEQUATE STORAGE CAPACITY. IF THE FACILITY IS TO
FUNCTION ULTIMATELY AS AN INFILTRATION SYSTEM, THE TEMPORARY FACILITY MUST BE ROUGH GRADED SO THAT THE
BOTTOM AND SIDES ARE AT LEAST THREE FEET ABOVE FINAL GRADE OF THE PERMANENT FACILITY. FLOW CONTROL BMP
AREAS (EXISTING OR PROPOSED) SHALL NOT BE USED AS TEMPORARY FACILITIES AND SHALL BE PROTECTED FROM
SEDIMENTATION AND INTRUSION.
13. COVER MEASURES WILL BE APPLIED IN CONFORMANCE WITH APPENDIX D OF THE KING COUNTY SURFACE WATER DESIGN
MANUAL.
14. PRIOR TO THE BEGINNING OF THE WET SEASON (OCT. 1), ALL DISTURBED AREAS SHALL BE REVIEWED TO IDENTIFY WHICH
ONES CAN BE SEEDED ON PREPARATION FOR THE WINTER RAINS. DISTURBED AREAS SHALL BE SEEDED WITHIN ONE WEEK
OF THE BEGINNING OF THE WET SEASON. A SKETCH MAP OF THOSE AREAS TO BE SEEDED AND THOSE AREAS TO REMAIN
UNCOVERED SHALL BE SUBMITTED TO THE DLS-PERMITTING INSPECTOR.
NOTE: ALL INSTANCES OF "APPLICANT/ESC SUPERVISOR" ABOVE SHALL BE CONSIDERED "CONTRACTOR/CONTRACTOR'S
ESC LEAD".
TESC NOTES:
1
SCALE: 1" =
0
FT
10'
10 20
CIVIL PLAN C02 S--
LEGEND:
APPROACH SLAB, SEE SHEET
S09 FOR DETAILS
HMA 6" CL 1/2" PG 58H-22 OVER
4" OF CSBC
STORM DRAINAGE PIPE
CATCH BASIN TYPE 1 PER CITY
OF RENTON STD PLAN 200.00
GENERAL NOTES:
1.SURVEY ELEVATIONS ARE APPROXIMATE.
CONTRACTOR TO SURVEY EXISTING
PAVEMENT LOCATIONS AND CONFIRM
EXISTING GRADE.
2.CONTRACTOR TO FIELD VERIFY RIM
ELEVATIONS BASED ON EXISTING
TOPOGRAPHY.
3.OUTFALL ELEVATIONS ARE FIXED, HOWEVER
UPSTREAM INVERTS AND CONNECTIONS TO
EXISTING PIPES NEED TO BE FIELD VERIFIED
AND SYSTEM CONFIRMED TO MIN 1% SLOPE
PRIOR TO ORDERING DRAINAGE
STRUCTURES.
CORNUS SERICEARED OSIER DOGWOODPHYSOCARPUS CAPITATUSPACIFIC NINEBARKHYDROSEED MIXMAHONIA AQUIFOLIUM 'COMPACTA'OREGON GRAPEROSA NUTKANANOOTKA ROSESPIRAEA DENSIFLORASUBALPINE SPIRAEAAPPROX. LIMIT OF FLOOD CONTROL WALL (VERIFY IN FIELD)APPROX. LIMIT OFDISTURBANCE (VERIFY IN FIELD)APPROX. LIMIT OFDISTURBANCE (VERIFY IN FIELD)RIVERBANK MIX PLANTINGPLANTING PLANL01S--SCALE:PLANTING PLAN1"=1'-0"1SCALE: 1" =0FT10'1020NEWSGENERAL NOTES:1.IRRIGATION - PROTECT IN PLACE. FIELD MODIFY AS REQUIRED.G
UY MICHAELSENNO. 730 EXP. 2/12/
2
025
STA
T
EOFWASHINGTONLANDSCAPE ARCHIT
E
CT
BACKFILL W/ PLANTING SOILSCORE ROOTBALL ON (3)SIDES TO 1/2" DEPTHUNDISTURBED ORCOMPACTED SUBGRADEPROVIDE WATERSAUCER BELOW MULCHFERTILIZER (NOTSHOWN) AS SPECIFIEDINSTALL 1" BELOWMULCH FINISH GRADEGROUNDCOVER PER PLANMULCH AS SPECIFIEDSPACING PER PLAN(TRIANGULAR UNLESS OTHERWISE NOTED)WEED BARRIER2X ROOT BALL DIAMTER1111ROOT BALL DIAMETERUNDISTURBED ORCOMPACTED SUBGRADEBACKFILL W/PLANTING SOILTAMP SOIL AROUND ROOTBALL W/ FOOT SO ROOTBALL DOES NOT SHIFTSHRUB PER PLANINSTALL 1" BELOWMULCH FINISH GRADEMULCH AS SPECIFIEDFERTILIZE (NOT SHOWN)AS SPECIFIEDPROVIDE WATERSAUCERWEED BARRIERSHRUBSQTY BOTANICAL NAMECOMMON NAMESIZE SPACINGCOMMENTS79CORNUS SERICEARED OSIER DOGWOOD3 GAL18" O.C.47MAHONIA AQUIFOLIUM 'COMPACTA'OREGON GRAPE5 GAL30" O.C.39PHYSOCARPUS CAPITATUSPACIFIC NINEBARK5 GAL48" O.C.46ROSA NUTKANANOOTKA ROSE1 GAL30" O.C.42SPIRAEA DENSIFLORASUBALPINE SPIRAEA3 GAL30" O.C.GROUNDCOVERS, PERENNIALS, GRASSESQTY BOTANICAL NAMECOMMON NAMESIZE SPACINGCOMMENTS565 SFRIVERBANK MIX10% CAREX OBNUPTASLOUGH SEDGE1 GAL12" O.C.20% CAREX STIPATASAWBREAK SEDGE1 GAL12" O.C.20% JUNCUS EFFUSUSCOMMON RUSH1 GAL12" O.C.10% JUNCUS ENSIFOLIUSDAGGERLEAF RUSH1 GAL12" O.C.10% JUNCUS TENUISSLENDER RUSH1 GAL12" O.C.10% JUNCUS PATENSGRAY RUSH1 GAL12" O.C.10% IRIS MISSOURIENSISWESTERN BLUE IRIS1 GAL12" O.C.10% SCIRPUS MICROCARPUSSMALL-FRUITED BULRUSH1 GAL12" O.C.470 SFHYDROSEED MIXPT 652 PACIFIC NORTHWESTWILDFLOWER MIX FROM PT LAWN SEEDSCALE:SHRUB PLANTING1"=1'-0'1SCALE:GROUNCOVER PLANTING1-1/2"=1'-0"2PLANTING SCHEDULE AND DETAILSL02S--G
UY MICHAELSENNO. 730 EXP. 2/12/
2
025
STA
T
EOFWASHINGTONLANDSCAPE ARCHIT
E
CT
APPENDIX B
PHOTOS
Photo 1: East Shoreline Looking South
Photo 2: East Shoreline Looking North
Photo 3: East Shoreline Landscaping
Photo 4: West Shoreline Looking South
Photo 5: West Shoreline Looking North
Photo 6: West Shoreline