YAKIMA, Wash. – The Bureau of Reclamation’s July 2024 forecast of total water supply available for the Yakima basin indicates the water supply will not fully meet irrigation demands this season. The total water supply available for the May 21–September 30 period indicates senior water rights will receive 100% of full entitlements, but junior water rights will receive 51% of their full entitlements.
Storage in the Yakima basin reservoirs on July 1 was 66% full with 703 thousand acre-feet, which is 74% of average. Precipitation for June was 159% of average and for October–June, was 85% 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 will provide an updated water supply forecast monthly—at least through July—using the latest data each month to reflect changing conditions as they develop. In a water-short year, Reclamation will add mid-month forecasts and forecasts after July as necessary to adjust for prevailing conditions.
The July forecast is based on flows, precipitation, snowpack, and reservoir storage as of July 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/.
