Priceville Sewer Board approved an 11.8 percent sewage rate increase for residential customers at its regular monthly meeting Monday night. The adjustment will become effective with billings made after Oct. 1, 2013.

In addition, a 10 percent rate adjustment was approved, effective Oct. 1, 2014, and Oct. 1, 2015.

Town of Somerville customers will see their sewage bills go up by 20 percent, effective Oct. 1, 2013, and again by the same amount, effective Oct. 1, 2014, and Oct. 1, 2015.

Board Chairman Jerry Welch pointed out that Priceville has not had a sewage rate increase since the department was organized in 1993.

“We working toward making the department self-sufficient by 2016, he said. “ We currently have 599 customers and project to add 100 households within the next three years. The additional revenue will support our current staff and enable us to keep pace with operational expenses.”

Priceville’s current base sewage rate is $9 per month, which covers the first 3,000 of water used by a household. In addition, a charge of $1.80 per month is made for each additional 1,000 gallons of water used.

The adjusted rate will be $10 per month plus $2.10 for each 1,000 gallons of water used above 3,000. For a Priceville family of four using 5,000 gallons of water per month, the increase amounts to $1.60 more per month. Somerville customers will pay 20 percent more.