RICHMOND, Va. (AP) -- A federal judge has ruled that the Environmental Protection agency exceeded its authority by attempting to regulate stormwater runoff into a Fairfax County creek as a pollutant.

U.S. District Judge Liam O'Grady in Alexandria ruled late Thursday in favor of the Virginia Department of Transportation and the Fairfax County Board of Supervisors, which challenged EPA's restrictions on the flow of stormwater into Accotink Creek.

The judge agreed with Attorney General Ken Cuccinelli, who argued that the EPA was trying to regulate water itself as a pollutant. In his ruling, O'Grady said: "Stormwater runoff is not a pollutant, so EPA is not authorized to regulate it."

Cuccinelli says the ruling could ultimately save Virginia taxpayers more than $300 million.

An EPA spokesman could not be reached for comment after business hours.