WILTON — Residents voted 12-4 Tuesday night to approve funding for improvements to the Wastewater Treatment Plant.

Fewer than 25 residents attended the special town meeting.

Voters accepted a $1.35 million grant and a $2.75 million loan from U.S. Department of Agriculture Rural Development to help fund the project. The estimated interest on the 30-year bond is $1.34 million, for a total debt of $4.09 million.

Other grants and loans will also help cover the $10.86 million upgrade to the 36-year-old plant, William Olver of Olver Associates in Winterport said.

William Rice asked what effect the upgrade will have on the sewer rate.

The 944 customers, on average, can expect to pay $85 per quarter on the debt service, or $340 a year more, Olver said. The rate will go from $420 to $760.

The town’s tax rate went up, “the national economy is hurting and you’re asking us to come up with $340 more a year?” Rice asked.

Built in 1978 with some unique features that brought in Department of Environmental Protection grants for its construction, the plant has exceeded a 20-year life expectancy. Wilton has gone 36 years without any major investments, Olver said.

Expecting an eventual overhaul, maintenance on the plant was deferred, Clayton Putnam, superintendent, said.

“Everything is on the edge. We’re right at a critical point,” he said. “If there wasn’t a need, we wouldn’t be here.”

The building is not up to new codes legislated in 2012, Selectperson Scott Taylor said. The new codes have increased the cost.

An upgrade to the department’s 31 pump stations was completed in 2012 in the first phase.

Since 2012, the project has been “gone over with a fine-toothed comb to find out what we could take out,” Putnam said.  “Right now, we are not in noncompliance but our permits are due to expire in 2016.”

There are always new regulations to consider to stay in compliance, he said.

The sewer system costs but it also brings value to the community, Putnam said. Businesses might not be in Wilton without the service, he said.

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