Cedar River climbs to Phase III flood alert

Snoqualmie, Green rivers also experiencing moderate flooding in areas

Increased flows from Chester Morse Reservoir mean that the Cedar River has reached a Phase III flood level early this morning, according to the King County Flood Warning Center.

The Cedar River was flowing at 3,634 cubic feet per second (CFS) near Landsburg at 3 a.m. The threshold for a Phase III flood alert on the Cedar is 3,500 CFS. Phase III on the Cedar is associated with areas of moderate flooding in the basin, particularly in the area of Lower Dorre Don Road and Byers Road.

Two other King County rivers remain at Phase III flood alerts – the Snoqualmie and Green rivers.

The sum of the Snoqualmie River’s three forks was flowing at 30,620 CFS at 3:30 a.m. The river peaked Sunday afternoon at 34,740 CFS, but the crest isn’t expected to reach Carnation until later today. At this flow level, moderate flooding of varied depths is expected to occur across the Snoqualmie Valley, and numerous roads could overtop and close.

The Green River also remains at a Phase III flood alert due to controlled water releases from Howard Hanson Dam. The river was flowing at 10,000 CFS at 2:45 a.m. The most likely flooding impacts at this level would occur in the rural areas without levees upstream of Auburn.

After reaching a Phase III flood alert Sunday, the Tolt River had receded to levels associated with a Phase II flood alert. The Tolt was flowing at 3,530 CFS at 3:45 a.m. Typically, minor flooding would be observed along the Tolt River at these flows.

King County opened its Flood Warning Center early Sunday morning to monitor rising flows on several King County rivers. The Flood Warning Center remains open to monitor conditions and flood patrol teams will be out inspecting flood control facilities.

Flood Warning Center staff will monitor stream gages and weather reports, and will provide updated information on river conditions as necessary. Real-time river level information is available online at http://www.kingcounty.gov/flood.

Updated information on flooding will also be posted on the King County website at www.kingcounty.gov, or via RPIN, the area's regional website at http://www.rpin.org. A recorded flood-information hotline is also updated each hour for citizens wanting information in flood areas. The number is 206-296-8200 or 1-800-945-9263.

Citizens who need help interpreting flood information should call 206-296-4535 or 1-800-768-7932. Problems on county maintained roads can be reported by calling 206-296-8100 or 1-800-KC-ROADS.

An automated flood alert system is now available and provides real-time warning of potential high water on more than a half-dozen rivers. King County residents and business owners can sign up to receive King County Flood Alerts by visiting www.kingcounty.gov/flood, or by calling 206-263-3400 during regular business hours to register by phone. Messages of potential high flows on any of King County’s major river systems can be sent by phone, text or e-mail.

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The King County Flood Control District is a special purpose government created to provide funding and policy oversight for flood protection projects and programs in King County. The Flood Control District’s Board is composed of the members of the King County Council. The Water and Land Resources Division of the King County Department of Natural Resources and Parks develops and implements the approved flood protection projects and programs. Visit http://www.kingcountyfloodcontrol.org for more information.

Related information

Flooding services and information

Cedar River - Lake Washington Watershed

Snoqualmie-Skykomish Watershed

How to prepare for a flood

King County Water and Land Resources Division