The mayors are squabbling over a proposal to rezone parts of the watershed around Lake Auburn, which requires more stringent designs for nearby septic systems.
The lake has a filtration waiver from the DEP, which reduces treatment costs. But the Lewiston mayor said that the Auburn City Council's recent approval to rezone nearly 150 acres near the lake to allow development would likely degrade water quality to the point where the sister cities would have to install an attrition plant costing millions of dollars.