He said the increases will help with expenses five to eight years out, including the impact of the phosphorus removal project.
The Plainville treatment plant must be upgraded to reduce the discharge of phosphorus into the Pequabuck River. In discussions with the state Department of Energy and Environmental Protection, Lee said the town will receive a 44 percent reimbursement.
The total town cost will be $9.2 million.
The town plans to fund its share through a state loan with a two percent interest rate. A referendum on the project is being considered for early next year.
The sewer fee increase will go into effect starting Nov. 1., and will last until October of next year.