Avista Managing Spokane River Levels Based on Snowpack, Rainfall
Avista has been adjusting its dam operations on the Spokane River to accommodate the seasonal flow this spring. It's one part optimizing power generation, and one part fine tuning the water level.
Avista operates several dams along the Spokane River from Post Falls downstream to the Little Falls Dam, adjacent to the Spokane Indian Reservation. It began the drawdown of Long Lake in February and March, so property owners could do work along the shore. And if you happen to drive past the Little Falls Dam right now, you might be surprised how it looks more like August than April.
This time of year the dams are adjusted according to how much runoff is coming from melting mountain snowpack, as well as rainfall. Although mountain snowpack is above average in many places, 110% of normal in the Spokane/Coeur d'Alene Basin, rainfall amounts have been down in recent weeks.
What's been happening this last week with this warm weather is we've had more flow into Coeur d'Alene Lake and more flow down the Spokane River," said Patrick Maher, a hydro operations engineer at Avista. "We've also been filling up Lake Spokane. We're running water through the turbines around the dam at either Little Falls or Long Lake."
Maher expects Long Lake will be filled by early next week. As the river flow increases with water from snowmelt, you can expect to see plenty of water coming over the top of Little Falls Dam and through its spillways.