YAKIMA, Wash. – The Bureau of Reclamation’s August 2025 total water supply available forecast for the Yakima basin indicates the water supply will not fully meet irrigation demands this season. The early estimate of the total water supply available for the May 20–September period indicates senior water rights will receive 100% full entitlements, but junior water rights will receive 40% of their full entitlements.
Storage in the Yakima basin reservoirs on Aug. 1 was 39% full with 414,781 acre-feet, which is 55% of average. Precipitation for July was 52% of average and for October–July was 76.9% of average.
Reclamation manages the water in the five Yakima Project storage reservoirs, along with the basin’s unregulated inflows to fulfill water rights, water contracts and instream flow obligations. Water shortages in the basin are shared equally by the junior water rights, which represent over half of the water rights in the basin.
Reclamation provides updated water supply forecasts monthly using the latest data each month to reflect changing conditions as they develop.
The August forecast is based on flows, precipitation, snowpack, and reservoir storage as of Aug. 1, along with estimates of future precipitation and river flows. Other future weather conditions that determine the timing of the runoff and the demand for water also are critical in determining stream flows, the extent to which the reservoirs fill, and the water supply for irrigation.
For more information, visit Reclamation’s website at https://www.usbr.gov/pn/hydromet/yakima/.