Final EPA-USGS Technical Report: Protecting Aquatic Life from Effects of Hydrologic Alteration

The Environmental Protection Agency (EPA) and the United States Geological Survey are releasing a technical report: Final EPA- USGS Technical Report: Protecting Aquatic Life from Effects of Hydrologic Alteration. Healthy aquatic ecosystems provide an array of services to individuals and society, including clean drinking water, irrigation supplies, and recreational opportunities. Sound and sustainable management of aquatic ecosystems is an integral part of managing water resources to meet the needs of society. Hydrologic alteration can be a contributor to the impairment of water bodies that are designated to support aquatic life. Stresses on aquatic life associated with hydrologic alteration may be further exacerbated by climate change. This report provides States, Tribes and territories with scientific and technical information on the natural flow regime and potential effects of flow alteration on aquatic life, and a flexible, nonprescriptive framework that state water managers might consider if they are interested in developing narrative or numeric targets for flow regime components that are protective of aquatic life. The report also provides information about States and Tribes that have adopted narrative water quality standards to protect their waterbodies' flow regimes and on the potential impact of climate change on flow regimes.