Phase IV flood alert level on Snoqualmie River, Phase II for Green, as rain continues

Officials at the King County Flood Warning Center say the Snoqualmie River, driven by heavy rainfall from a powerful tropical storm, has risen to a Phase IV flood alert level early Wednesday morning. Dangerous widespread flooding is likely to occur throughout the Snoqualmie Valley.

The Flood Warning Center, which opened Tuesday afternoon to monitor conditions, has also just issued a Phase II flood alert level for the Green River, where only minor flooding is expected. Meanwhile, the Tolt River remains at a Phase IV flood alert level and Issaquah Creek is at a Phase II flood alert level.

At 5:45 a.m. Wednesday, the sum of the Snoqualmie River’s three forks was 41,000 cubic feet per second (cfs), which is well above the Phase III flood alert threshold of 38,000 cfs.

At these flows, flooding can be expected across the entire Snoqualmie Valley, with some residential areas experiencing dangerous high velocities and the closure of major transportation routes.

The Green River above Auburn was flowing at 7,300 cfs as of 5:45 a.m. Wednesday morning. At these flows, only minor flooding of agricultural areas in the Green River Valley above Auburn would be anticipated.

The Tolt River near Carnation continues at a dangerous Phase IV flood alert level. As of 5 a.m., the Tolt was flowing at 11,800 cfs, still well above the Phase IV flood alert level of 7,000 cfs. At this level, levees could overtop near Carnation, and major roadways could be closed because of fast, deep floodwaters.

Issaquah Creek, which had been at a Phase III flood alert level, has dropped down to a Phase II flood alert level.

Motorists are reminded to obey all emergency road closure signs. The number-one cause of fatalities in flooding is from people who ignore emergency road closure signs and who drive into deep, swift water.

Flood Warning Center staff are monitoring stream gauges and weather reports, and will provide updated information on river conditions as necessary. Flood patrol crews are also monitoring conditions from the field.

Flood Warning Center staff will continue to monitor stream gauges and weather reports and provide updated information on river conditions as necessary. Real-time river level information is available online at http://www.kingcounty.gov/environment/waterandland/flooding/warning-system.aspx.

Updated information on flooding will also be posted on the King County Web site at www.kingcounty.gov, or via RPIN, the area's regional Web site 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.

Related information

Flooding Services and Information

River and Floodplain Management Section

Water and Land Resources Division