DIXFIELD — The Board of Selectmen voted unanimously Monday night to hike the basic quarterly sewer bill by 7 percent, which is less than half the increase recommended by the town’s auditor.

The new rate will appear in the Oct. 1 sewer bill for the system’s 580 users.

The board will revisit the issue in early January to learn whether another rate hike will be needed.

Monday’s decision to raise the rate followed a 95-minute public hearing where many people questioned the need for it.

Auditor Ron Smith recommended an increase of 19 percent — from $62.33 to $74.75 — because of a lack of funds in the sewer department reserves, a debt of $50,000 to the town and loan repayment.

Smith said the increase is needed for the current $103,000 loan for the replacement of the sewer main beneath the Webb River Bridge, and an anticipated loan of $116,000 in 2013 for replacement of sewer pipes just over the bridge to the Peru-Mexico Bridge entrance.

He also said the amount of depreciation on the sewer system should be placed in reserve each year. For the Dixfield system, that amount would be $158,000 to $165,000.

“The town has never put aside money for the future,” Smith said.

At issue is an apparent miscalculation of the sewer usage and need for reserve funds when the rates were last changed five years ago.

Some residents also questioned whether the town should continue to contract with sewer system experts, Ted Berry Co. of Livermore, for the maintenance of pump stations and sewer lines.

“For years, public works maintained the system. Public works has not decreased, but we are doing more contracting,” Sonya Fuller said.

“Can we crunch some numbers now? Can public works do some of Ted Berry’s work? We aren’t looking into this deep enough,” resident Dan McKay said.

Town Manager Eugene Skibitsky said the town has a four-year contract with the Ted Berry Co. This is year two.

The town pays the company between $55,000 and $66,000 annually for the maintenance of the sewer system.

Board Chairman Mac Gill said if another rate increase is needed, a public hearing will be held first.