Reclamation Information Sharing Environment (RISE)

In 2019, the Reclamation Snake River Area Office (SRAO) requested the Technical Service Center (TSC) Sedimentation and River Hydraulics group to conduct a collaborative investigation into potential sources of pressures impacting the physa snail community downstream from Minidoka Dam. The initial aim of the project was to test the hypothesis that operational conditions of the dam periodically disturb critical snail habitat through release and deposition of detritus into bedrock pools immediately downstream. The project scope was highlighted by a series of coordination meetings, a site visit, literature review, and exploratory data analysis. TSC has concluded that the initial trajectory of couching the problem in the context of monitoring suspended sediment transport and deposition is likely too narrow in focus. Although reservoir operations are highly likely to be an important factor, consideration of water quality effects and the biology of the physa snail are also relevant. The TSC staff involvement lacked subject matter expertise pertaining to the latter and therefore the study was unlikely to reveal causal effects without significant rescope. Herein, we summarize work performed along with reasons for concluding the study preemptively.