Coulee Dam instructed the town’s attorney last week to file a lawsuit against Elmer City for breach of a decades-old contract between the two towns, saying Elmer City isn’t paying its bills.

Following an executive session of the town council Wednesday night, the council voted unanimously to sue. Mayor Greg Wilder said Elmer City was in arrears at least $55,000 in charges Coulee Dam has billed for processing the smaller town’s sewage, more if certain capitalized costs are included.

“They’ve overcharged us for labor for years,” Elmer City Mayor Gail Morin said Thursday morning, adding that Coulee Dam has also been trying to bill for those capital costs, which she said aren’t allowed by the contract.

“For the past 38 years, we were subsidizing Coulee Dam’s wage distribution a little at a time,” Morin contended.

She said Elmer City had received a $64,000 bill last month that included charges for a new pickup, past engineering studies on Elmer City’s “smelly sewage,” and for land Coulee Dam bought nearby in preparation to build a new wastewater treatment plant. Elmer City decided to pay just sewer treatment operating costs, about $9,300, she said.

Morin claimed Coulee Dam has billed based on operating costs that include 100 percent of the plant operator’s time, but she said he doesn’t spend all his time at the plant.

She said Elmer City had never been billed for capital costs before Wilder took over as mayor.