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Cedar River - Lake Washington Watershed

The Cedar River - Lake Washington Watershed is the land area in which rainwater drains to Lake Washington and out through the Hiram Chittenden Locks. The Cedar River - Lake Washington watershed includes the Cedar River and its tributaries, May Creek, Coal Creek, Mercer Island, Mercer Slough, Kelsey Creek, Fairweather Creek, Yarrow Creek, Juanita Creek, Forbes Creek, Lyon Creek, McAleer Creek, Thornton Creek, and Ravenna Creek. The Sammamish River drainage is also part of the greater watershed, but is published on a separate page.

Introduction to watersheds

Basin Steward Program
Look up watershed experts to get answers to questions and help solve watershed related problems.

Community service centers
Information about King County's satellite offices including the Black River community center in the Cedar River watershed at Renton. Office address is 900 Oaksdale Ave. S.W., Renton, WA 98055, phone number 206-296-7810. The Covington community service center is located at 27331 172nd Ave. SE, # 116, Covington, WA 98042, phone number 206-296-1387. The Northshore community service center is located at 10808 N.E. 145th St., Bothell, WA 98011, phone number 206-296-9840.

Flooding and hydrology

Cedar River Flooding, 1996Cedar River flooding information
Look up real time gage data, flood stage info and learn what it means along the Cedar River.

Hydrologic gage data map
Look up detailed gaging station data for creeks and rivers in the region.

Flood related video interview by Kim Hill with Larry Phillips, Kathy Lambert, Mark Isaacson
Watch Video:
Preventing flood disasters
King County is at work this summer repairing levees
RealPlayer needed to watch this video.
Video length 22 minutes, 22 seconds.

Surface water management and groundwater

Lake Washington water quality data
This page offers an overview of Lake Washington water quality issues and provides graphs of water quality data from several sampling locations on the lake, spanning several years. Graphs display temperature, dissolved oxygen, pH, conductivity, nitrogen, phosphorus, chlorophyll, bacteria, tranparency, and other data.

Lake Union water quality information

Henderson/ Martin Luther King combined sewer overflow project
A stormwater storage tunnel project in the Rainier Beach area of South Seattle, designed to keep Lake Washington clean.

Swimming beach data
Find information about levels of bacterial pollution and relative human health risks at swimming beaches on Lake Washington, Lake Sammamish, and other King County lakes.

Streams Monitoring Program
Keeping watch for pollution in greater Lake Washington streams. Water quality data are available online for:

Cedar River - Lake Washington watershed map
Drainage map displaying streams, lakes, drainage divides, major roads and cities in the area that drains to Lake Washington and out the Hiram M. Chittenden Locks, except for the Sammamish Watershed area. The map is in Acrobat format. File size is 445 Kb.

Lake Washington existing conditions report - 2004

South King County Groundwater Management Area
Learn about plans to protect the aquifer in the south county area including the Cedar River watershed localities of Renton, Black Diamond, Maple Valley, and areas in between.

Endocrine disrupting chemicals in the environment
Learn about these natural and synthetic chemicals flushed daily into our waters, and discover what King County is doing to protect public health and the environment as the science and our understanding of endocrine disruptors develops.

Final Adopted May Creek Basin Action Plan
This plan provides regulatory guidance, programs, and projects aimed to reduce the threat of flooding to citizens in the May Creek Basin, to make improvements to effectively handle stormflow while stabilizing stream banks and reducing erosion, to protect and enhance fish and wildlife habitat and water quality in the basin, and to take reasonable steps to prevent existing problems from worsening in the future. May Creek flows into Lake Washington.

Lake Washington looking west toward the Olympics The Lake Washington story

Lower Cedar River basin plan summary
An overview of the issues and recommendations in the Basin Plan

Salmon & trout recovery

WRIA 8 salmon recovery
Lake Washington, Cedar River, and Sammamish
This site provides information about the recovery of threatened salmon species in the Sammamish, Lake Washington, and Cedar River drainage area including an overview of the planning process, scientific information, and meeting records. We welcome your participation.

Habitat inventory and assessment of Juanita Creek in 2000
A report on instream and riparian salmon habitat quality in Juanita Creek in the Kirkland area of north King County.

Fish and wildlife enhancement project
A capital improvement project to improve fish and wildlife habitat in Cedar River Wetland 79 near Maple Valley.

Wastewater treatment

Go to Brightwater Treatment Facilities Brightwater treatment systyem
Major improvements to the sewage treatment system serving King and Snohomish Counties including the Cedar/Lake Washignton watershed area. The Brightwater project encompasses a new treatment plant, its associated conveyance pipes, outfall to Puget Sound and an environmental education center. The system is under construction now (2009).

Juanita Bay pump station replacement project
Details about a project to to increase wastewater handling capacity and ensure safe and reliable operation.

Lake Washington & the Cascade Range

Recreation and appreciation

Lake Shorelines, Life on the Edge Video Series Includes Video (Windows Media format) New
Watch a video that describes lakes in King County and how residents value them, with ideas that shoreline landowners may like to apply to help preserve the quality of lakes and lake ecosystems.

Cedar River public boating and fishing access
Find parks, ecological natural areas and boat ramps to access the river for swimming, fishing and boating. Includes lands managed by the City of Renton, King County and City of Seattle.

King County Natural Areas:

Look up individual properties protected in King County's open space system for their ecological and working resource values. The natural lands site provides addresses, pictures, location maps and rules for public use:

Cedar River trail
The Cedar River trail follows an old railroad right-of-way from downtown Renton to King County's Landsburg Park, alongside the scenic Cedar River. A branch of the trail connects with King County's Lake Wilderness Park and continues to Four Corners.

Kayaker Boating on the Cedar River: review our flooding and habitat projects, and look at the boaters page for safety tips, boating signals, and other useful info.

Miscellaneous

Aerial Photograph of BellevueHistoric and recent aerial photographs
Aerial photos from the 1930's, 1970's and 1990's illustrating growth of Bellevue in the East Lake Washington basin and Fairwood in the Cedar River basin, among other areas in King County.

Related information

Related agencies

News and announcements

Nov. 13, 2009
King County adds new alert system to public safety tools for flood season

Nov. 6, 2009
External release, Port of Seattle
Port of Seattle Announces New Partners in Rail Corridor
King County, Sound Transit, others join in preserving 42-mile line

Oct. 11, 2009
Crews respond quickly to wastewater overflow at temporary pump station in Bellevue

It's Salmon Seeson again!Spot the spawners in the Lake Washington, Cedar and Sammamish Watershed

Jul. 31, 2009
King County making crucial repairs to levees; Portion of Cedar River Trail closed during work

Jul. 14, 2009
Busy flood levee construction season gets under way along King County rivers
Ambitious work schedule follows emergency repairs from winter storms

May 28, 2009
Learn more about proposed open space charter amendment at upcoming public meetings

Apr. 30, 2009
Community, students helping shape future of King County’s Skyway Park

Apr. 18, 2009
External report, KING5 News
Tugboat sinks, spills diesel in Lake Washington

Mar. 16, 2009
Council acts to reduce levels of harmful phosphorus in County lakes and streams
Patterson initiative limits use of fertilizers that choke oxygen out of waterways

Feb. 20, 2009
King County needs volunteers to help save native plants for future habitat restoration
March 7 native plant salvage in Maple Valley; Volunteers also needed at nursery

Jan. 31, 2009
FEMA Opens Disaster Recovery Center In King County

Jan. 31, 2009
External article, Seattle Times
Flooding victims in 8 counties can request federal help

Jan. 30, 2009
Presidential declaration of disaster issued for flood event in King County

Jan. 27, 2009
King County residents affected by flooding can receive vouchers for free flood debris disposal

Jan. 23, 2009
Juanita Bay Pump Station replacement increases system capacity, improves design

Jan. 22, 2009
King County checking for more flood damage as emergency levee repair work is completed

Jan. 12, 2009
External article, Seattle Times
King County to open flood-damage hotline

Jan. 12, 2009
External article, Seattle Times
As nature's buffers disappear, flooding becomes routine in Puget Sound region

Jan. 11, 2009
King County crews make progress opening and repairing flood-damage roads and levees
Flood Warning Center closes as river levels drop

Jan. 10, 2009
Damage assessment and debris removal begin as flooding recedes
King County and city officials help residents clean up flood debris

Jan. 10, 2009
Emergency repairs under way to flood-damaged levees
Safety information available for citizens returning to damaged homes

Jan. 9, 2009
Historic flows, significant road and structure damage visible as King County Executive tours flood damaged communities

Jan. 8, 2009
Flooding cuts off residents in East King County
Levee upgrades, farm pads keeping residents and animals safer this year

Jan. 7, 2009
Cedar River joins Tolt, Snoqualmie rivers at Phase IV flood alert
After receding, Issaquah Creek climbs back to Phase III flood alert

Jan. 7, 2009
Drinking water wells, septic systems at risk during floods

Jan. 7, 2009
Residents, motorists urged to stay safe as King County experiences historic flooding

Jan. 7, 2009
Green, Cedar river levels climb; dangerous levels persist on Tolt, Snoqualmie

» Archived News and Announcements