West Virginia and eight other states are suing over new water regulations criticized as overly burdensome on farmers and landowners.
On Tuesday, West Virginia Attorney General Patrick Morrisey announced the lawsuit against the U.S. Environmental Protection Agency and U.S. Army Corps of Engineers. It was filed in southern Georgia federal court.
The rule would expand federal authority over the bodies of water the EPA can legally regulate, aiming to protect small streams, tributaries and wetlands.
The states say the rule violates the Clean Water Act, the Administrative Procedure Act and the Constitution.
West Virginia joins Alabama, Florida, Georgia, Kansas, Kentucky, South Carolina, Utah and Wisconsin in the lawsuit.
Thirteen other states filed a similar challenge Monday, as did another group of three states.
The rule takes effect Aug. 28.