A Prince William County taxpayers group filed suit in Circuit Court yesterday against the county Board of Supervisors to dismantle the new county water and sewer authority, saying the issue should have been decided by referendum.

The county board approved the authority last month despite protests from citizens who said the board did not adhere to the Virginia Water and Sewer Authority Act. They said the act required the board to estimate costs of the authority and to submit the issue to referendum if requested. The board did neither.

"We feel the county's action was wrong, and we feel it is our duty to do something about it," said Claude Bradshaw, a plaintiff in the suit.

The suit asks that the authority be dissolved if the court decides the supervisors violated state law. The plaintiffs are six residents and the Taxpayers Association for Prudent Spending, which represents 100 residents, said J. Allen Walker, the group's attorney.

"We will cooperate and we will prevail," board Chairman Kathleen Seefeldt said of the suit. "We accepted the advice of special legal counsel and I'm confident the advice was sound." She said the suit was "politically motivated" and that some of those opposed to the authority may run against board members in November.

The authority is aimed at streamlining water and sewer services. Its supervisor-appointed, five-member board sets rates and contracts out the services in neighborhoods without them, though the supervisors have final say on rates and contracts.