Like the river on a hot day in August, the Yakima River Basin Water Enhancement Project (YRBWEP) is a slow-moving process. Congress originally authorized YRBWEP in 1979, with major amendments in 1984 and 1994. Congress has now passed the first amendments to YRBWEP of this century in the John D. Dingell, Jr. Conservation, Management, and Recreation Act, which is awaiting President Trump’s signature. These newest amendments would provide additional authorization for Phase III of YRBWEP. Where Phase I and II focused on fish passage and water conservation, respectively, Phase III focuses on increasing storage capacity for the Yakima Basin.

The Yakima Basin reservoirs currently only have the capacity to store about 30% of the basin’s annual runoff across its five reservoirs. The snowpack is called the “sixth reservoir,” but with climate change the reliability of that “reservoir” has been declining. More precipitation tends to fall as rain, and the snow that does fall melts sooner, meaning that less water is available later in the irrigation season. The Yakima Basin Integrated Plan is intended to address these problems by expanding storage capacity for liquid precipitation. However, until now the only storage component of the plan that Congress had authorized was the Cle Elum pool raise.

This new law authorizes two projects for Phase III of YRBWEP: the Kachess pumping plant and the Keechelus to Kachess pipeline. In water-short years, the pumping plant would access stored water in Lake Kachess that is too low to be released from the reservoir’s outlet. This water would be supplied to pro-ratable irrigation districts. The Keechelus to Kachess pipeline would then move water to refill Lake Kachess after pumping events, as well as to moderate flows out of Lake Keechelus to provide better fish habitat below Lake Keechelus’s outlet. These two projects would still have to undergo permitting and environmental review prior to construction.

Most of the remaining projects discussed in the Integrated Plan, such as additional fish passage, additional projects to increase storage capacity, and groundwater recharge projects, would need to first be identified by the Secretary of Interior, receive additional congressional approval, and undergo further environmental review before moving forward.