The Bureau of Reclamation's May 2012, Total Water Supply Available (TWSA) forecast for the Yakima Basin indicates there will be a full water supply for both senior and junior water rights.

"We are expecting an above average water supply at this time," said Chuck Garner, Yakima Project River Operations supervisor. "Above average snowpack and reservoir levels in early May will keep the Total Water Supply outlook above average even after the heavy runoff event we experienced in the last week of April."

At this time both junior and senior water rights holders are expected to receive their full water supply. The water supply forecast will be updated each month through July. Specific water delivery levels will not be determined until later in the year when the reservoir system's storage begins to decline.

The May TWSA forecast is based on flows, precipitation, snowpack, and reservoir storage as of May 1, along with estimates of future precipitation and river flows. Other future weather conditions that determine the timing of the run-off and the demand for water are also critical in determining streamflows, reservoir storage, and the water supply available.

"The snowmelt timing, the summer weather, and the irrigation demands are still important unknown factors that can influence streamflow levels and the carry-over storage at the end of the season," Garner said.

He advises all water users in the Yakima Basin to use their water prudently.

For more information visit our website at