Flood alert for Green River following releases from Howard Hanson Dam as rain continues to fall | King County Flood Warning Center

Controlled water releases from dam expected to send Green River to Phase II flood alert level. King County Flood Warning Center open and monitoring minor flood flows.

The King County Flood Warning Center has issued a Phase II flood alert for the Green River, as heavy rainfall that continues to pummel the region brings minor flooding to a handful of rivers.

Based on planned water releases from Howard Hanson Dam, the Green River is expected to exceed the Phase II flood alert threshold by 6 a.m. Sunday. Only minor flooding is likely to occur, and only in the rural areas without levees upstream of Auburn. These increased flows are not expected to have any impact to the cities of Auburn, Kent, Renton or Tukwila.

King County opened its Flood Warning Center early Sunday morning to monitor rising flows on several King County rivers, including the Snoqualmie and Tolt rivers, which have both reached the Phase II flood alert level.

As of 2:30 a.m., the Tolt River was flowing at 3,810 cubic feet per second (CFS). Typically, only minor flooding would be expected at this flow.

Meanwhile, at 2:30 a.m. the sum of the Snoqualmie River’s three forks was at 18,190 CFS. At this flow level, minor lowland flooding would be expected in low-lying areas along the Snoqualmie River.

phone. Messages of potential high flows on any of King County’s major river systems can be sent by phone, text or e-mail.