Through collaborative efforts earlier this summer, the Bureau of Reclamation and the State of Wyoming reached an agreement on last spring’s water management operations for the Upper Snake River basin to avoid impacts to fisheries below the Jackson Lake Dam in Grand Teton National Park.
Uncommon hydrologic conditions created an imbalance in the Upper Snake reservoir system during the 2023 water year, with water levels low in the upper reaches (Jackson Lake) and high in the lower reaches. The imbalance created the potential for a loss of storable water in the reservoir system if flows were to have spilled past Milner Dam in southern Idaho.
As water conditions evolved, Reclamation was able to operate the reservoir system to meet flood risk requirements, avoid water supply storage loss, and maintain 280 cubic feet per second below Jackson Lake Dam without use of Wyoming’s contracted space in Palisades Reservoir. Following peak runoff in June, Reclamation coordinated with managing partners and began operating Jackson Lake Dam to meet downstream demands.
“We do not expect any widespread or significant impacts to the Snake River fishery from the Jackson Lake dam operations this spring,” Darren Rhea, Wyoming Game and Fish Department fisheries supervisor in the Jackson Region said. “Reclamation was able to maintain minimal flows from the dam to support the river and preserve the Oxbow, while strong runoff from large tributaries immediately downstream helped augment the typical spring flow and sustain critical habitat throughout the river.”
As part of the agencies’ continued commitments to transparency and collaboration, planning for fall agency and public meetings is underway, where resource managers will discuss water operations outlook, fisheries, and research opportunities to support future management. Additionally, Reclamation plans to share with the public foundational information about how federal reservoir systems operate. The public meetings are slated for Sept. 14, 2023, more information to follow.
“As federal stewards, we recognize our tremendous responsibility to work with our partners to continue providing the many benefits of the upper Snake system while finding solutions that are good for fish and for people. We look forward to seeking those opportunities for win-win solutions,” said Snake River Area Manager Lanie Paquin.
Reclamation and the state of Wyoming will work together to review and, if needed, update the 1996 Guidelines for Decision-Making in Operation of Wyoming’s Contracted Space in Palisades Reservoir to promote a greater shared understanding and enhance future coordination efforts. This undertaking also will include collaboration with Idaho water users, as well as other interested stakeholders. Through these discussions, Reclamation is committed to finding long-term solutions that address Wyoming’s concerns, while meeting its contractual obligations and operational responsibilities.