Benefits Of Fish Passage And Protection Measures At Hydroelectric Projects

The US Department of Energy's Hydropower Program is engaged in a multi-year study of the costs and benefits of environmental mitigation measures at nonfederal hydroelectric power plants. An initial report (Volume 1) reviewed and surveyed the status of mitigation methods for fish passage, instream flows, and water quality; this paper focuses on the fish passage/protection aspects of the study. Fish ladders were found to be the most common means of passing fish upstream; elevators/lifts were less common, but their use appears to be increasing. A variety of mitigative measures is employed to prevent fish from being drawn into turbine intakes, including spill flows, narrow-mesh intake screens, angled bar racks, and lightor sound-based guidance measures. Performance monitoring and detailed, quantifiable performance criteria were frequently lacking at non-federal hydroelectric projects. Volume 2 considers the benefits and costs of fish passage and protection measures, as illustrated by case studies for which performance monitoring has been conducted. The report estimates the effectiveness of particular measures, the consequent impacts on the fish populations that are being maintained or restored, and the resulting use and non-use values of the maintained or restored fish populations.

The focus of this report is technologies for fish passage around hydropower generation facilities and protection against entrainment and turbine mortality. Emphasis is given to Federal Energy Regulatory Commission (FERC)-licensed hydropower projects where fish protection is a subject of controversy and congressional interest due to the Federal Power Act (FPA) and the Electric Consumers Protection Act (ECPA). Thus institutional issues related to FERC-relicensing are also discussed. (Major points of controversy are high-lighted in box 1.1).

This study examines envirorunental mitigation practices that provide upstream and downstream fish passage and protection at hydroelectric projects. The study includes a survey of fish passage and protection mitigation practices at 1,825 hydroelectric plants regulated by the Federal Energy Regulatory Commission (FERC) to determine frequencies of occurrence, temporal trends, and regional practices based on FERC regions. The study also describes, in general terms, the fish passage/protection mitigation costs at 50 non-Federal hydroelectric projects. Sixteen case studies are used to examine in detail the benefits and costs of fish passage and protection. The 16 case studies include 15 FERC licensed or exempted hydroelectric projects and one Federally-owned and-operated hydroelectric project. The 16 hydroelectric projects are located in 12 states and range in capacity from 400 kilowatts to 840 megawatts. The fish passage and protection mitigation methods at the case studies include fish ladders and lifts, an Eicher screen, spill flows, airburst-cleaned inclined and cylindrical wedgewire screens, vertical barrier screens, and submerged traveling screens. The costs, benefits, monitoring methods, and operating characteristics of these and other mitigation methods used at the 16 case studies are examined.

This study examines envirorunental mitigation practices that provide upstream and downstream fish passage and protection at hydroelectric projects. The study includes a survey of fish passage and protection mitigation practices at 1,825 hydroelectric plants regulated by the Federal Energy Regulatory Commission (FERC) to determine frequencies of occurrence, temporal trends, and regional practices based on FERC regions. The study also describes, in general terms, the fish passage/protection mitigation costs at 50 non-Federal hydroelectric projects. Sixteen case studies are used to examine in detail the benefits and costs of fish passage and protection. The 16 case studies include 15 FERC licensed or exempted hydroelectric projects and one Federally-owned and-operated hydroelectric project. The 16 hydroelectric projects are located in 12 states and range in capacity from 400 kilowatts to 840 megawatts. The fish passage and protection mitigation methods at the case studies include fish ladders and lifts, an Eicher screen, spill flows, airburst-cleaned inclined and cylindrical wedgewire screens, vertical barrier screens, and submerged traveling screens. The costs, benefits, monitoring methods, and operating characteristics of these and other mitigation methods used at the 16 case studies are examined.

The Department of Energy, through its hydropower program, is studying environmental mitigation practices at hydroelectric projects. The study of environmental mitigation is intended to provide greater understanding of environmental problems and solutions that are associated with conventional hydroelectric projects. This volume examines upstream and downstream fish passage/protection technologies and the associated practices, benefits, and costs. Fish passage/protection mitigation technologies are investigated by three methods: (a) national, regional (Federal Energy Regulatory Commission regions), and temporal frequencies of fish passage/protection mitigation are examined at 1,825 operating and conventional (excludes pumped storage) Federal Energy Regulatory Commission (FERC) regulated hydroelectric sites in the United States; (b) general fish passage/protection mitigation costs are discussed for 50 FERC regulated hydroelectric projects; and (c) 16 case studies are used to examine specific fish passage/protection mitigation practices, benefits, and costs.

Obstruction of fish movements by dams continues to be the major environmental issue facing the hydropower industry in the US. Dams block upstream migrations, which can cut off adult fish form their historical spawning grounds and severely curtail reproduction. Conversely, downstream-migrating fish may be entrained into the turbine intake flow and suffer turbine-passage injury or mortality. Hydroelectric projects can interfere with the migrations of a wide variety of fish. Maintenance, restoration or enhancement of populations of these species may require the construction of facilities to allow for upstream and downstream fish passage. The Federal Energy Regulatory Commission (FERC), by law, must give fish and wildlife resources equal consideration with power production in its licensing decisions, must be satisfied that a project is consistent with comprehensive plans for a waterway (including fisheries management plans), and must consider all federal and state resource agency terms and conditions for the protection of fish and wildlife. As a consequence, FERC often requires fish passage mitigation measures as a condition of the hydropower license when such measures are deemed necessary for the protection of fish. Much of the recent research and development efforts of the US Department of Energy's Hydropower Program have focused on the mitigation of impacts to upstream and downstream fish passage. This paper descries three components of that effort: (1) a survey of environmental mitigation measures at hydropower sites across the country; (2) a critical review of the effectiveness of fish passage mitigation measures at 16 case study sites; and (3) ongoing efforts to develop new turbine designs that minimize turbine-passage mortality.