HomeMy WebLinkAboutEx_09_Stream_Assessment
ATTACHMENT 20: STANDARD
STREAM OR LAKE STUDY
Exhibit 9
Docusign Envelope ID: D31D61AF-180E-439C-B708-0C917E2644A7
425-869-2670 ■ 15325 SE 30th Place, Suite 300 ■ Bellevue, Washington 98007 ■ www.dowl.com
Stream Classification
The Windsock Apron is adjacent to (within 200 feet of) the Cedar River and its floodplain area.
The Cedar River is classified as a Shoreline of the State by Renton Municipal Code (RMC) 4-3-
090. This project is entirely outside of and will not interact with the floodplain area.
Vegetative Cover
The Windsock Apron project area is entirely covered with pavement. The surrounding
areas to the south and west are mowed grasses. There is a narrow strip of grass to the
east and then a fence. Outside of the fence, there is a narrow strip of riparian vegetation
including trees and shrubs.
The proposal will not impact any vegetation in the vicinity of the Cedar River.
Ecological Functions
Overall, the reach of the Cedar River that flows through Renton has limited ecological functions
due to urban development. Access to the floodplain is limited and the channel has been
straightened. Trees and shrubs along the bank provide shading and nutrient input. However, the
riparian corridor is limited due to adjacent development.
The Cedar River provides instream habitat for salmonid species and prey species including
sculpin and lamprey. The Cedar River serves as an important migration corridor, as it outlets to
Lake Washington which outlets to the Puget Sound.
The proposal will not result in any impacts to the ecological functions provided by the Cedar
River.
Fish and Wildlife Use
The Cedar River provides habitat for resident and migratory salmonid species including sockeye
(Oncorhynchus nerka), coho (Onchorhynchus kisutch), Chinook (Oncorhynchus tshawytscha),
cutthroat trout (Oncorhyncus clarki), kokanee (Oncorhyncus nerka), steelhead (Oncorhyncus
mykiss), Dolly Varden (Salvelinus malma), and bull trout (Salvelinus confluentus). Other
documented fish species in the Lower Cedar River watershed include mountain whitefish
(Prosopium williamsoni), northern squawfish (Ptchochelius oregonensis), several species of
sculpin (Cottus sp.) and western brook lamprey (Lampetra richardsoni).
Observations on e-Bird for the Renton-Cedar River Trail (on the east side of the river, opposite
from the Renton Municipal Airport) included typical urban species including American crow,
European starling, Canada goose, mallard, dark-eyed junco, song sparrow, spotted towhee,
red-winged blackbird, American goldfinch. Waterfowl (including western grebe, ring-billed gull,
double-crested cormorant, red-breasted merganser, and various species of ducks) and raptors
(osprey, bald eagle and Cooper’s hawk) were also reported. There are no known nests or
feeding/foraging areas in the vicinity of the project area.
The proposal will not impact fish or wildlife species. Construction activities may result in
temporary noise impacts which may result in bird species temporarily avoiding the project area.
DATE: July 22, 2024
SUBJECT: Renton Aprons – Stream Assessment Narrative
Docusign Envelope ID: D31D61AF-180E-439C-B708-0C917E2644A7
MEMORANDUM
Page 2 of 2
However, the project is in an urban area and species in this area are already subject to noise
from urban and aviation activities. Therefore, construction noise is not anticipated to result in
any significant disturbance to any species.
Tree Protection Measures
The project does not include any tree removal. Therefore, no tree protection measures are
required.
No Net Loss of Ecological Functions
The project will not alter the existing conditions and will not result in any impacts to the Cedar
River. Therefore, the project will not result in any loss of ecological functions and is compliant
with the No Net Loss requirements described in RMC 4-3-090D2.
Docusign Envelope ID: D31D61AF-180E-439C-B708-0C917E2644A7
Docusign Envelope ID: D31D61AF-180E-439C-B708-0C917E2644A7