Eightmile Dam Near Leavenworth Has New Spillway, Is Being Monitored

May 21, 2018

Outside of Leavenworth, Washington, crews have been working on a dam in trouble. 

Last week, officials were worried about major thunderstorms raising the water level behind the Eightmile Lake Dam. A bad wildfire in 2017 left the watershed vulnerable to increased runoff, and the near-century-old dam has been compromised by a clogged release pipe.

But those storms largely went to the south.

Now, the irrigation district that owns the dam has installed a new 55-foot spillway of large rocks to reinforce the structure.

Irrigation district officials say they plan to install a siphon pipe to help drain down the lake. And when the water goes down they’ll lock in the larger rocks with gravel and sand.

The state has also installed rain gauges and lake level-monitoring devices so the reservoir can be watched around the clock.

Officials say they’ll remain worried about potential storms until they can bring the lake level down.