Streamflows and the water supply remain below normal in several Idaho river basins, the USDA Natural Resources Conservation Service reported June 5, with shortages possible in parts of the east-central mountains.

Snowpack on June 1 was near or above normal in the Panhandle and Clearwater basins in the north, and the Upper Snake basin in the east.

Snowpack was below normal in Salmon, West Central and Bear basins to the south and east.

“As a result, aside from northern Idaho and far-eastern Idaho, where remainder-season streamflow is forecast to be near normal, the rest of the state should anticipate lower-than-normal runoff,” NRCS Idaho Supervisory Hydrologist Danny Tappa said in a news release.

Median streamflow forecasts in the Wood and Lost basins, in the east-central mountains, range from 10-55% of normal. Precipitation for the water year, in which many storms largely missed the area, ranges from 60-80%.

Reservoir storage is near or above normal to date, including supplies carried over from last year. NRCS Idaho said irrigators may struggle to receive adequate water supplies during the irrigation season.

Chris Johnson, source water protection specialist with the Idaho Rural Water Association, told Capital Press the supply in the Wood River watershed likely will be short unless the area receives unseasonable precipitation this summer.

Mid-May rains improved supplies in west-central basins, NRCS said. Precipitation for the month ranged from 80% to 110% of normal.

Year-to-date precipitation as of June 1 ranged from 70% to 80% of normal after Weiser, Payette and Boise basins improved since early May. Reservoir storage is above normal, though dry winter conditions leave streamflow forecasts at 45-70% of normal.

Most southside-Snake basins have below-normal precipitation for the year, though storms May 18-24 provided a boost.

Streamflow forecasts range from 30% to 85% of normal, except for the Owyhee River at 40-60%. Above-normal storage in reservoirs will help provide an adequate water supply.