Evaluation of Fry and Juvenile Fish Survival in Spillways and Drop Structures (WD1-FY03-005-BOR)
* Do in-river diversion structures provide safe downstream passage for young fish?
* Do some structure designs provide less injury and mortality to young fish than others?
Need and Benefit
There are many non-anadromous fish native to the Western United States that migrate upstream to spawn. In recent years, many fishways have been constructed on run-of-river diversion dams to improve upstream fish passage. Little is known about the survival of young fish passing downstream over spillways and through energy dissipation structures. Research in this area is very limited. A study on salmonid survival following impact in water by Copp (US Army Corps of Engineers [Corps], 1968) is often cited, even though its application to non-salmonids, juveniles, and fry is unknown. This research will focus on survival of young non-salmonids passing through several types of energy dissipation structures. For each fish species tested, base line survival will be established by evaluating fish survival in a free falling jet into a pool. Drop heights of 5 to 20 feet will be tested.
Tests will then be conducted of baffled apron drops, spillways with hydraulic jump basins, and Type 6 impact basins. Each test will include controls and test fish to separate out mortality due to test procedures. Initially, fish from projects where there is an immediate concern will be tested. The tests will be conducted in the Water Resources Research Laboratory (WRRL). Fishery biologist from D-8220 will assist in the research.
Contact the Principal Investigator for information about partners.
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.
Fish Passage for Non-Salmonids (final, PDF,
By Brent Mefford
Publication completed on September 30, 2006