U.S. EPA has proposed for public comment new standards for cooling water intake systems at large existing power plants and factories. The new standards are designed to provide protections for fish that may otherwise be killed by the large-volume water intakes.

The proposed new regulations grow out of a settlement with Riverkeeper and other environmental organizations regarding EPA’s CWA Section 316(b) cooling water intake regulations.  Under that settlement, EPA is supposed to take final action on new rules by July 27, 2012.

For fish impingement (being pinned against the intake structure) the proposed rules would cover facilities that withdraw at least 25% of their water exclusively for cooling purposes, and have a design intake flow greater than 2 million gallons per day. Controls would be imposed to limit the fish kills. Fish entrainment (being drawn into the cooling water system) would be addressed at facilities that withdraw at least 125 million gallons per day, and controls would be implemented on a site-specific basis.