Court battles since 2007 ended Tuesday when the Arizona Supreme Court denied a request from the town of Marana to review a case related to wastewater systems.
The Arizona Court of Appeals sided with Pima County in June, saying the town lacks legal authority to own or operate a sewer plant it seized from the county earlier this year.
The Arizona Daily Star reports County Administrator Chuck Huckelberry said he will ask state and federal authorities to take action because, without the proper legal authority, Marana is operating the plant in violation of the Clean Water Act.
Marana also must pay $170,000 to $180,000 in legal fees to the county, as awarded by the court.
Marana, meanwhile, is not pulling back on its plans to own and operate its own wastewater system.
The town council last month approved a ballot initiative for the March town primary election to ask voters to give the town legal authority to own and operate the county plant and other wastewater facilities connected to it.