Area residents using the Boothbay Harbor Sewer District will pay at least $80.30 on their quarterly bills in 2014.

The rate hike was driven by the need for capital improvement projects following the Boothbay Harbor Sewer District Board of Trustees rate studies and public hearings late last year.

“What (the trustees) did was look over a 20-year period, and this year it's going to be more equipment stuff in the plant, and then after that, we're going to start looking at putting some money into the system to try to catch up on the last 60 years,” Sewer District Supervisor Chris Higgins said.

In 2013 the minimum quarterly rate was $73.67 per 900 cubic feet of basic facilities. The minimum rate will be raised by $6.63, which will amount to an annual increase of at least $26.

Higgins said although there are several ways the district can fund projects, federal grant money has been curtailed and is becoming tougher to get.

In 2013 the sewer district was looking to piggyback with the water district's upcoming project on Campbell Street, however, the costs of installing public sewer exceeded $430,000.

“There's still money out there, but we would have to increase our debt in order to put (Campbell Street) in, and the trustees weren't willing to take on debt for that project,” Higgins said. “They had more substantial priorities elsewhere in the system.”

The district's priorities for the immediate future include replacing the sewer treatment plant's equipment that's nearing shelf life, and preparing to replace the old sewer lines that date back to the 1960s.

Higgins said the old asbestos cement piping has weakened over time due to the acidity of the soil eating away at the lime on the pipes. With a lifespan of about 75 years, Higgins said portions of the pipe will be "sliplined" from manhole to manhole to avoid the high cost of replacing pipes and roads through excavation.

Sliplining entails relining the inside of old pipes with a resin adhesive that strengthens the pipe and increases the flow of waste water.

About 50 percent of the sewer district's 25 miles of pipes are asbestos cement, Higgins said, so the district would be looking to implement the project over the next 10 to 15 years.

As the value of the district's equipment depreciates over time, the cost to replace it is partially covered by ratepayers. In order for the district to be completely self-sustaining, the quarterly rate would have to double to $12.75 per 100 cubic feet, which in an ideal world could work, Higgins said, “But nobody could afford to fund 100 percent of it. It just isn't going to happen.”

With an annual depreciation rate of over $300,000, Higgins said the nine percent rate ($6.63 per quarter) increase will cover roughly $130,000 of the annual depreciation rate.