NE 40th Street Stormwater Treatment Retrofit

Project Overview

Construction of a stormwater runoff treatment facility to improve water quality in Lake Sammamish and Villa Marina Creek. A study identified two areas of SR520 and NE 40th Street that have inadequate stormwater runoff treatment and represent the highest pollutant load to Lake Sammamish from streets in Redmond.

Microsoft, as part of their commitment to environmental sustainability, is providing funding for this project through a Community Facilities District. The City is seeking grant funding to allow the facility to treat a larger area than can be completed with available funding.

The new treatment facility will remove oils and grease, sediment, dissolved metals, and phosphorous to protect the threatened Chinook salmon, native kokanee salmon, coho salmon and sockeye salmon the inhabit these waters.

For more information on this project:  SEPA Project Details (PDF)

Related Environmental Documents
Feasibility and Alternative Analysis (PDF)
Geotechnical Report (PDF)