Summary

King County closed its Flood Warning Center at 5 p.m. on Saturday, March 21, after monitoring minor to moderate flooding along several rivers since Tuesday evening, March 17, when a potent atmospheric river pushed through the region and sent river levels soaring.

News

Update: 5:30 p.m. on Saturday, March 21

With heavy rainfall easing and river flows receding in the upper river basins, the King County Flood Warning Center closed at 5 p.m. on Saturday, March 21, after nearly four full days of ‘round-the-clock activation to closely track minor and moderate flooding along a handful of rivers.

Flood Warning Center staff will continue to track river levels and weather data in case these improving conditions change unexpectedly.

King County’s Flood Warning Center is staffed 24/7 during flood events, serving as an information clearinghouse for the public and other agencies responsible for ensuring public safety.

King County offers everyone free access to KC Flood Alerts, an automated system with customized flood alerts on King County major river systems. When you sign up for KC Flood Alerts, you’ll get immediate notifications about pending high water via email, text or voicemail, giving subscribers with the maximum amount of warning about potential flooding.

Track real-time conditions for six rivers and Issaquah Creek with the Flood Warning App, which was developed by the King County Flood Control District and King County as service provider.

Install the app on your phone or desktop to help inform your important safety decisions before, during, and after flood events. Information is available in multiple languages with Google Translate. Launch or install the app at kingcounty.gov/flood.

Update: 3:45 p.m. on Friday, March 20

The Green River has reached a Phase 2 flood alert level, with minor flood impacts to low-lying areas along the river upstream of Auburn.

At 3 p.m. the Green River at Auburn was flowing at 7,020 cubic feet per second, slightly higher than the Phase 2 flood alert threshold of 7,000 CFS. Some low-lying areas in the largely rural Green River Valley upstream of Auburn could experience minor floodwaters, however no impacts are expected in the City of Auburn or farther downstream in the Green River Valley.

Elsewhere in the county, the Snoqualmie and Tolt rivers are each at a Phase 3 moderate flood level with multiple road closures from water over roadways. King County flood patrol teams have been monitoring conditions in these watersheds since the early hours of Friday morning. The White and Cedar rivers are at the lower Phase 2 flood alert level.

With road closures from floodwaters likely to continue for several hours in the hardest hit areas, it’s a good idea to visit King County’s  MyCommute for the latest road closure information. Current river flows and forecasts can be found on the King County Flood Warning website, kingcounty.gov/flood or call 1-800-945-9263.

Update: 3:30 a.m. on Friday, March 20

The Tolt River reached a Phase 3 flood alert at about 2:45 a.m. on Friday, March 20, when river flows exceeded the moderate flood phase threshold of 5,000 cubic feet per second at Carnation.

Floodwaters could flow over sections of the Tolt River Road Northeast upstream of 6005 Tolt River Road Northeast. Floodwaters could also seep and cause backyard flooding along the south bank of the river between Snoqualmie Valley Trail Bridge and the State Route 203 Bridge.

The Snoqualmie River is also at Phase 3, while the White and Cedar rivers are at the lower Phase 2 flood alert level. King County’s Flood Warning Center dispatches two-person flood patrol teams to monitor levees along all rivers at a Phase 3 flood alert level or higher.

With road closures likely affecting travel later today, it’s a good idea to visit King County’s  MyCommute for the latest road closure information. Current river flows and forecasts can be found on the King County Flood Warning website, kingcounty.gov/flood or call 1-800-945-9263.

Update: 1:30 a.m. on Friday, March 20

For the second time this week, heavy rainfall has pushed flows on the Snoqualmie River up to a moderate flood level with the potential for flooding of varied depths across the Snoqualmie Valley, according to the King County Flood Warning Center.

As of 1:15 a.m. on Friday, March 20, the sum of the Snoqualmie River’s three forks was 20,630 cubic feet per second, surpassing the Phase 3 flood alert threshold of 20,000 CFS. Numerous road closures are possible at these flows in the Snoqualmie Valley – check out King County’s MyCommute for the latest road closure information.

The Cedar, Tolt and White rivers all continue to experience minor flooding early Friday morning.

The Flood Warning Center has been operating continuously since 7:45 p.m. on Tuesday, March 17, and serves as an information clearinghouse for the public and other agencies responsible for ensuring public safety during a flood event.

Current river flows and forecasts can be found on the King County Flood Warning website, kingcounty.gov/flood or call 1-800-945-9263.

Update: 7:30 p.m. on Thursday, March 19

The King County Flood Warning Center has issued a Phase 2 flood alert for potential minor flooding along the Cedar River east of Renton.

As of 7 p.m. on Thursday, March 19, the Cedar River at Landsburg was flowing at a rate of 3,040 cubic feet per second, easily past the Phase 2 threshold of 2,800 CFS for the river. At these flows, a few roads in low-lying areas along the river could overtop and close, including Southeast 184^th Street and Lower Dorre Don Way Southeast.

The Cedar is the latest of several rivers across the county to see higher flows from the powerful atmospheric river that soaked much of the Puget Sound region earlier in the week. The Tolt, Snoqualmie, South Fork Skykomish, and White rivers are all at Phase 2 flood alert levels as of 7 p.m. Thursday, March 19.

The Flood Warning Center has been operating continuously since 7:45 p.m. on Tuesday, March 17, and serves as an information clearinghouse for the public and other agencies responsible for ensuring public safety during a flood event. Current river flows and forecasts can be found on the King County Flood Warning website, kingcounty.gov/flood or call 1-800-945-9263.

Update: 10:30 a.m. on Wednesday, March 18

The Snoqualmie River surpassed the Phase 3 flood alert threshold at about 9:45 a.m. on Wednesday, March 18, indicating flooding of varied depths across the Snoqualmie Valley, and additional road closures. Check out King County’s MyCommute for the latest road closure information.

The Tolt River reached this moderate flood phase just about 90 minutes earlier on Wednesday. Flood patrols will now check conditions along both rivers and report any issues back to the Flood Warning Center.

At the other end of the county, the White River remains at a Phase 2 flood alert level, with minor impacts in and around the City of Pacific.

Update: 9 a.m. on Wednesday, March 18

The Tolt River reached a Phase 3 flood alert at 7:45 a.m. on Wednesday, March 18, when river flows exceeded the moderate flood phase threshold of 5,000 cubic feet per second at Carnation. Floodwaters could flow over sections of the Tolt River Road Northeast upstream of 6005 Tolt River Road Northeast. Floodwaters could seep and cause backyard flooding along the south bank of the river between Snoqualmie Valley Trail Bridge and the State Route 203 Bridge.

The Department of Natural Resources and Parks deploys members of its Flood Patrol when rivers reach Phase 3. Flood patrol members are department employees who are specially trained to monitor levees, reporting their findings to the Flood Warning Center.

The White and Snoqualmie rivers remain at Phase 2 flood alert levels, with minor flooding possible in low-lying areas along those rivers.

Update: 5 a.m. on Wednesday, March 18

The White River reached a Phase 2 flood alert at 4:45 a.m. on Wednesday, March 18, when flows exceeded the minor flood phase threshold of 5,000 cubic feet per second at Mud Mountain Dam upstream of Pacific. Overbank flooding may occur in the City of Pacific near Government Canal and within Pacific City Park. High water will likely occur along the temporary flood protection barriers.

The Snoqualmie and Tolt rivers remain at Phase 2 flood alert levels.

Update: 4:15 a.m. on Wednesday, March 18

The Tolt River reached a Phase 2 flood alert level at 3:30 a.m. on Wednesday, March 18, when flows exceeded the minor flood phase threshold of 3,500 cubic feet per second. At these flows, the levee along the south bank of the river between the Snoqualmie Valley Trail bridge and State Route 203 bridge could experience seepage.

The Snoqualmie River remains at a Phase 2 flood alert level, with minor flooding possible along Southeast Reinig Road, Meadowbrook Road, Mill Pond Road, Neal Road Southeast, and a handful of other roads.

Original post: 7:45 p.m. on Tuesday, March 17

The King County Flood Warning Center opened at 7:45 p.m. on Tuesday, March 17, to monitor minor flooding on the Snoqualmie River with possible impacts to roads in low-lying areas – the result of a strong Pineapple Express that brought steady rainfall to the region.

As of 7:45 p.m. on Tuesday, March 17, the sum of the Snoqualmie River’s three forks was recorded at 12,190 cubic feet per second, just surpassing the Phase 2 flood alert threshold of 12,000 CFS.

At these flows, some minor flooding could occur – with potential floodwaters along Southeast Reinig Road, Meadowbrook Road, Mill Pond Road, Neal Road Southeast, and a handful of other roads.

With weather forecasts calling for more rain and warm temperatures melting heavy recent snowfall, additional minor to moderate river flooding is expected on some King County rivers over the next few days.

The Flood Warning Center is staffed 24/7 during flood events. The center serves as an information clearinghouse for the public and other agencies responsible for ensuring public safety during a flood event. Current river flows and forecasts can be found on the King County Flood Warning website, kingcounty.gov/flood or call 1-800-945-9263.

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