(Left) A New York power plant with a once-through cooling water intake system that can trap aquatic wildlife. (Right) Fish and other organisms can be pinned against cooling water intake screens like these. (Inset) Fish found impinged on this outdated and dangerous equipment.

NEW YORK—For a fish, a seal or even a sea lion, swimming too close to a power plant could spell disaster. A rule recently upheld by a federal court takes a step toward protecting aquatic life from being sucked into cooling water intakes at these plants—but it’s a missed opportunity to do more.

On July 23, the 2nd U.S. Circuit Court of Appeals upheld an Obama-era cooling water intake rule issued by the Environmental Protection Agency (EPA). The rule, issued in 2014, regulates the intake of cooling water at some 1,000 large power plants and manufacturing facilities.

Currently, the intake of water from rivers, lakes, bays and oceans to cool processing equipment at these facilities kills or injures billions of fish and other aquatic life annually. Fish eggs, larvae and small organisms are sucked in along with the cooling water (entrainment), while adult fish and shellfish and larger animals are pinned against the screens protecting the cooling water pumps (impingement). NELC attorneys—working with a coalition of lawyers from Riverkeeper, Sierra Club and the Center for Biological Diversity— had argued that the rule did not go far enough and thus violated both the Clean WaterActandtheEndangeredSpeciesAct.

At the same time, we filed briefs opposing arguments, made by a coalition of industry groups, that the rule should be set aside in its entirety because of alleged overreach and procedural irregularities.

“The court’s ruling is something of a mixed bag,” explained NELC Litigation Director Chuck Caldart. “On the one hand, the court missed a critical opportunity to set a national standard requiring the installation of closed cycle cooling—which the EPA concedes is by far the most effective technology for reducing harm to aquatic life—at the great majority of facilities where it would be feasible.”

“On the other hand,” Caldart noted, “the court flatly rejected industry attempts to scrap the rule. Instead, the court interpreted the rule in a way that provides ‘teeth’ to provisions that might have been read more generally. This is likely to boost the rule’s effectiveness.”

NELC and the other environmental group attorneys are considering the possibility of filing a petition for rehearing on certain aspects of the court’s opinion.