PROVIDENCE, R.I. – Six Northeast states sued the U.S. Environmental Protection Agency, claiming its rules on power plants’ water use will cause fish kills and other environmental harm.

The EPA published regulations in July 2004 outlining how power plants nationwide can use water from bays, rivers, lakes, oceans and other waterways for cooling.

Critics of the plants say they take in too much water and that the warm water they discharge harms aquatic life unable to adjust to drastic temperature changes.

The lawsuit claims the EPA rules make it easier for power plants to avoid the cost of new technologies that would limit water use and protect the environment.

The lawsuit was filed July 5 by Rhode Island, Connecticut, Delaware, Massachusetts, New York and New Jersey. Arguments were expected in March.