Magic, Mackay and Salmon Falls Reservoirs in Central Idaho are likely to run out of irrigation water in July, federal water experts say. But whitewater boaters should see good flows.
Most Snake River and Boise irrigators' supplies appear adequate according to the Natural Resources Conservation Service. Most of May’s moisture came early and the area that needed it most – Central Idaho’s Big Wood, Little Wood and Big Lost basins – recorded a fraction of their normal May amounts. “The lack of snow and spring rains in the mid-elevations resulted in limited runoff and soil that is already drying out,” said Ron Abramovich, Water Supply Specialist with the Idaho Natural Resources Conservation Service. “Additional moisture during the spring snowmelt season would have benefited dryland farmers.” North Idaho received below average precipitation as well but with the above normal snowpack this winter, streamflow forecasts are at or above normal,” said Abramovich. “The flows will provide excellent whitewater rafting opportunities.” Reservoir operators in southern Idaho are in the process of completing final fill while other reservoirs have peaked and are being drafted. The natural lakes and reservoirs elsewhere in the state will fill or come close to filling and should provide adequate irrigation supplies.
This is sharp contrast to California and other southwest states that are suffering a deep drought that has left farmers short and already has brought serious fires. The Gold Fire in the Sawtooths south of Stanley is Idaho's first fire of consequence growing to 80 acres by Thursday.
Carryover storage for next year will depend on summer temperatures and precipitation that affect irrigation water demand, Abramovich said.