Ririe Dam proposal seeks to boost winter water storage

IDAHO FALLS, Idaho (KIFI)- Public comments are being accepted through Nov. 16 on a joint proposal by the U.S. Army Corps of Engineers and the Bureau of Reclamation to increase winter water storage at Ririe Dam and Reservoir.

The proposed changes call for retaining an additional 6,000 to 7,500 acre-feet of water during the winter months while maintaining downstream flood protection.

The Bureau of Reclamation owns the Ririe Dam and Reservoir, while the Army Corps of Engineers manages flood control operations under federal law. The ongoing study examines whether winter flood control space can be reduced to improve water availability for local irrigators and communities. A 30-day public comment window opened Oct. 16 to gather local input and technical feedback before agency leaders decide whether to proceed.

Technical modeling shows the reservoir could hold an additional 6,000 acre-feet of winter water without necessitating winter releases. Expanding storage up to 7,500 acre-feet would require clearing snow, ice and debris from the downstream flood control channel prior to forecasted winter storms to ensure safe releases.

Tracy Krause, lead hydrologist for the Army Corps, noted that channel clearing has been successfully performed in the past. “We have shown that it is possible to clear that flood control channel through physical means,” Krause said. “And so that is a viable option.”

Army Corps representatives emphasized that the technical study focuses strictly on physical storage capacity rather than water rights allocation among specific agricultural users.

“For us here in the Army Corps, we have a responsibility to protect the communities downstream from flooding,” said said Lt. Col Douglas Droesch, Commander and District Engineer for the Walla Walla District. “And so any changes that we consider, they've got to uphold that responsibility.”

For more information on the project and on how to submit public comment, click this link here.

Following the close of the public comment period on Nov. 16, officials will assemble a decision document package in January. If recommended for approval, the package will be submitted to the Northwestern Division commander for final review.

The joint study is expected to conclude in February or March of 2027. If approved, agencies will begin updating the reservoir's official water control manual.