Hydrokinetic turbines installed in riverine, tidal, and ocean habitats have the potential to impact fish populations, particularly if fish are entrained through operating units and suffer injury and mortality. A primary concern associated with the passage of fish through hydrokinetic turbines is the potential for fish to be struck by turbine blades. To address this issue, a laboratory evaluation was conducted to evaluate fish entrainment and turbine passage survival for an axial-flow turbine developed by Free Flow Power. Testing was conducted in a large flume at approach velocities of about 1.5 and 2.0 m/s. Test species included rainbow trout, hybrid striped bass, and white sturgeon. High turbine survival rates (98-100%) were observed for fish that passed through the turbine during tests in which a containment net prevented downstream movement around the unit. During behavioral trials conducted without the containment net, active avoidance of turbine entrainment was noted for trout and bass, whereas sturgeon appeared to move passively downstream with little or no attempts to avoid entrainment. Total passage survival estimates were calculated for each species and test velocity by combining turbine survival estimates and avoidance probabilities. Total survival was essentially 100% for all test conditions, with the exception of hybrid striped bass evaluated at a velocity of 1.5 m/s (94%). This study has produced valuable data that can be used to assess potential impacts of hydrokinetic turbine projects on fish populations.
Evaluation of Survival and Behavior of Fish Exposed to an Axial-Flow Hydrokinetic Turbine
Title: Evaluation of Survival and Behavior of Fish Exposed to an Axial-Flow Hydrokinetic Turbine
January 01, 2014
Document Number: 3002003911
Amaral, S.; Giza, D.; McMahon, B. (2014). Evaluation of Survival and Behavior of Fish Exposed to an Axial-Flow Hydrokinetic Turbine. Report by Alden Research Laboratory. pp 76.