According to the Bureau of Reclamation’s March 2023 Total Water Supply Available (TWSA) forecast for the Yakima basin, there seems to be adequate supply to meet irrigation demands this upcoming season. The early estimates of the TWSA for the April-September period indicates that senior water rights will receive 100% of entitlements and junior water rights will receive 86% of entitlements.
Beyond that, storage in the Yakima basin reservoirs as of March 1th was 49% of capacity, or 521 thousand acre-feet, which is 82% of average.
Precipitation was 72% of average for February, and was 74% of average for October-February. On March 1, the amount of water in the snowpack, known as snow water equivalent, was 91% of average.
The water is managed in five Yakima Project storage reservoirs, which are used along with other unregulated flows into the basin to fulfill water rights, water contracts and in stream flow obligations. However, water shortages in the basin are shared equally by the junior water rights, which represent over half of the water rights in the basin.
An updated water supply forecast will be provided on a monthly basis (at least through July) using the latest data each month to reflect any changing conditions, by the Bureau of Reclamation.