Round Butte Dam Selective Water Withdrawal

 

Round Butte Dam Selective Water Withdrawal

Power Generation and Associated Fish Passage Facility

2010/2011 Accomplishments

James Bartlett 

Portland General Electric, Madras, Oregon

Portland General Electric and the Confederated Tribes of the Warm Springs Reservation of Oregon have been operating the new Selective Water Withdrawal (SWW) and associated Fish Transfer Facility (FTF) for approximately one year.  The water intake structure screens approximately 6,000 cfs of surface water to exclude fish from the power house flow while directing the fish to the capture facilities.  The fish passage facilities are designed to capture fish according to size, biologically sample, recycle, and transport resident species and downstream migrating salmon and steelhead.  The Fish Facility, Juvenile Collection, Downstream Transportation, and Release evaluation studies focused on analyzing data collected on fish capture and passage performance for naturally reared smolts and juvenile and adult resident fish captured and processed at the collection facilities.  The studies also evaluated the performance of the fish collection and sampling facilities relative to the 93% safe passage standard established for naturally reared salmonids during the first five years of operation.  The safe passage standard applies to fish survival from the time they are captured at the SWW to the time they are released into the lower Deschutes River below the project.  Chinook smolt survival was 98.2%, Steelhead smolt 98.5%, and sockeye smolt was 97.7%.  Test fish and sample sizes varied from only a few fish to observe behavior in relation to facility components such as the fish separators, to larger groups of test fish to identify facility induced injury or mortality that may be associated with a particular component, or a series of components within a various system.  Because of the difficulty in isolating injury to individual components, the tests were completed separately for the capture and separation facilities, and for the holding and processing, and transport facilities.  The fish passage facilities component and segment testing objectives and results will be further discussed during the presentation.