Water managers get passing grade for Flood Control So Far from this Ole Rancher
The Flathead River Basin has been challenging this water year for water managers. At the time I write this, precipitation since October is over 129 percent of normal and the current snow pack (Snow Water Equivalent or SWE) is at 137 percent above normal.
Snow water equivalent is the amount of water that will be released from the snowpack when it melts. The Bureau of Reclamation operates Hungry Horse Reservoir and the Confederated Salish and Kootenai Tribes own and operate the former “Kerr” Dam.
I give both agencies a passing grade so far for minimizing high flows and controlling flood conditions on the main stem Flathead River this spring.
The Flathead River at Columbia Falls has been above flood stage (13.0 ft.) several times. Predictions by the Northwest River Forecast Center expect the Flathead to climb to about 13.81 ft. and approximately 48,000 cubic feet per second on or about May 31, before receding once again.
Both agencies have worked hard to release flows based on modeling, real-time measurement conditions in the watershed, and managing storage in their respective pools. Most of the snow pack has already melted at the lower and mid- elevations in the basin. The real concern now is the high elevation snow pack coming off all at once either through high temperature periods or a significant rain on snow event.
Since March, the overall average SWE for the Flathead Watershed has been above average and has ranged from about 20-30 inches. High elevation (above 6,000 ft.) snow telemetry sites in the basin still show in some locations over a 100 inches of snow depth and more than half of that is SWE. To me, that is a large and scary amount of snow high in our basin for this time of year.
As I write, the current Flathead Lake level is about 2.5 ft. from full pool. We farmers and ranchers along the mainstem Flathead are caught in the middle, and our properties and livelihoods are dependent in part on smart and effective water management. Too much high flow contributes to erosion of the streambanks and overtopping into our farm fields. Additionally, too much high groundwater for prolonged periods can contribute to lost crop production.
We are watching closely what happens in June. Will the Flathead River at Columbia Falls reach 14 or 15 feet or go even higher? Currently, there is approximately 9,500 cfs more coming into the lake than discharging from it. How high will the lake get and how fast will it come up?
In 2012, by June 20 we had over 5 inches of precipitation and the water was over my dock. I live on a small tributary to the mainstem river. Both agencies deserve praise so far. They will need to work even harder during the next few weeks to minimize flood peaks and control flooding on the mainstem Flathead River. We will be watching and will hold them accountable. Thank you to the men and women who manage these awesome water resources — keep up the good work!
Storer is a resident of Bigfork