Fish Guidance Systems

US EPA 316(b) ruling opens way for Acoustic Fish Deterrents

After long delays the US Environmental Protection Agency published on May 19 the final ruling on Section 316(b) of the Clean Water Act, which requires power plants and other facilities that withdraw surface water for plant cooling to reduce the impact of their abstractions on fish and shellfish.

The new rule offers flexible options for reducing impacts on aquatic wildlife and allows for use of multiple technologies to achieve compliance. This mirrors established practice in Britain and continental Europe, where combinations of acoustic fish deterrents (AFDs) and drum- or band-screens modified for fish handling and return have been in use for well over a decade now. Impingement reduction targets are often not achieved by fish-handling screens alone, as delicate pelagic species which can dominate the catch rarely survive handling. On the other hand, they are mostly very sensitive to sound and can be efficiently deterred (typically 90%+) by AFD. The combined systems therefore meet Best Available Technology requirements of the regulatory authorities. Additional fish deterrence, e.g. for eels, is achieved by adding strobe lights at some sites.

Fish Guidance Systems has been in discussion with the Electric Power Research Institute (EPRI) with a view to identifying power plant operators willing to participate in trials of FGS acoustic and light based fish deterrent systems. AFDs are suitable for intakes with a wide variety of fish species, but facilities most likely to benefit through cost savings from FGS technology are those withdrawing from coastal waters and estuaries, or on river and lake systems where impingement of pelagic species such as shads and alewife is significant.

Any plant operators wishing to find out about whether their plant would be suitable please contact Dr David Lambert or Dr Andy Turnpenny at FGS.