Underwater Curtain Technology for Enhancing Downstream Fish Passage in Storage Reservoirs

Project ID: 6884
Principal Investigator: Dale Lentz
Research Topic: Fish Passage and Entrainment
Funded Fiscal Years: 2012
Keywords: curtain, entrainment, reservoir

Research Question

Passage is an issue both for upstream migrants (usually adult fish) and downstream or outmigrants (usually juveniles). To access habitat above the reservoir, upstream migrants must locate the fishway, pass through the fishway and over the dam, and then pass through the reservoir. Outmigrants on the other hand tend to be weaker swimming fish that must pass through the reservoir, locate downstream passage routes around or through the dam, and then pass through those routes to the tailwater. Juvenile outmigrants likely are susceptible to predation that may be aggravated by exposure to turbulent flow conditions that yield injury or disorientation. Large reservoirs with confused current patterns (as influenced by temperature stratification, wind, inflows, and outflows) can pose a significant migration barrier.

The challenge with re-establishing runs lies with collecting and passing the outmigrant juveniles. We know there are many natural lakes through which smolts migrate with little apparent disorientation or delay. This spawns the question: how can we better emulate natural lakes with storage reservoirs? This research proposes to investigate the use of underwater curtain technology for enhancing downstream passage of salmon smolts in storage reservoirs.

Need and Benefit

Quality fisheries spawning and rearing habitat is at a premium. Large storage reservoirs are responsible for blocking access to many miles of prime upper watershed habitat. Developing fish runs through reservoirs will greatly enhance fish habitat and river restoration. Underwater curtains for fish guidance has been tried in a few locations and are of interest to fisheries groups, but they have not been well researched. Underwater curtains may be an effective way to re-establish historical fish runs.

Contributing Partners

Contact the Principal Investigator for information about partners.

Research Products

Bureau of Reclamation Review

The following documents were reviewed by experts in fields relating to this project's study and findings. The results were determined to be achieved using valid means.

Underwater Curtain Technology for Enhancing Downstream Fish Passage in Storage Reservoirs (final, PDF, 554KB)
By Dale Lentz
Report completed on October 03, 2012

Underwater Curtain Technology for Enhancing Downstream Fish Passage in Storage Reservoirs. The goal of this scoping project was to research different reservoir fish collection facilities and at the feasibility of using the existing upstream under water curtain at Wiskeytown reservoir to test and demonstrate the ability to guide and catch downstream migrants so they could be transported downstream past the reservoir.

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Last Updated: 6/22/20