A series of rain storms with warm temperatures will be impacting Western Washington through the upcoming weekend and into early next week.

For this upcoming period, the U.S. Army Corps of Engineers does not expect the amount of precipitation in the basins of the Green and White rivers to create operational challenges for its dams.

The Corps keeps the reservoirs empty at Mud Mountain Dam along the White River, as well as Howard Hanson Dam along the Green River until storage is required for flood risk management.

This weekend’s stream of rain systems may require some storage at both dams.

Flood fight teams and reservoir managers at the Corps’ Seattle District are on alert and poised to respond as necessary.

However, there is a risk of flooding for property owners along the non-leveed middle Green basin, the rural portion of the river upstream from Auburn to Howard Hanson Dam. Potential flows of 9,000 cubic feet per second as measured at the Auburn gauge are possible. Such flows currently trigger a

flood warning from the National Weather Service due to flooding concerns in the Middle Green River. These flows do not present flooding concerns for areas downstream, including Auburn, Kent, Tukwila or Renton.

At certain levels – 6,000 cfs along the White River and 9,000 cfs along the Green River – Corps emergency management observers will be sent along the

river to make on-the-spot visual assessments and communicate information back to the Seattle District’s reservoir control center and make assessments of river conditions and levee-system integrity.

The Corps’ Seattle District maintains and controls Mud Mountain and Howard Hanson Dams and is in constant communication with local jurisdictions regarding its operations at those projects. Current flow information for any of the river basins in Western Washington may be found by clicking here.