The cooling water intake structures allowed for by the EPA rule draw billions of gallons of water each day from rivers and estuaries across the country and collectively destroy tens of billions of fish per year and trillions of organisms per year overall, including individuals from at least 266 federally threatened and endangered species such as sea turtles, environmental groups say. 

Once-through cooling systems also discharge trillions of gallons of heated water back into these waterways, transferring trillions of BTUs of heat hourly. The resulting unnaturally warm water further disrupts local ecosystems, even causing fatal heat shock to some passing organisms while also drawing manatees to habitats that are otherwise too cold to sustain the sea cows. Environmentalists say that these impacts have stressed and depleted riparian, lake and coastal ecosystems for decades, and in many cases cooling systems have recorded fish kills exceeding that of the fishing industry.

“From the Gulf of Maine, down the Eastern Seaboard, on the Atlantic and Gulf Coasts of Florida, from the Mississippi River Delta to the headwaters of the Missouri River, and all along the Pacific Coast, cooling water intake structures are jeopardizing the continued existence of hundreds of threatened and endangered and damage their critical habitat,” said Marc Yaggi, executive director of Waterkeeper Alliance. “We are taking action to compel NMFS and FWS to properly analyze the impacts of outdated and destructive once-through cooling and to impose effective measures to protect our vulnerable, endangered aquatic species.