The expanded plant will have to reduce nitrogen and phosphorous discharge to meet federal requirements for reducing pollution of the Chesapeake Bay, Rundquist said.
How big the plant will be has more to do with the future of the townships than the borough, which will have developed all of its open land within a few years, Council President William McLaughlin said.
"The townships have between 25,000 and 30,000 lots out there" waiting to be developed, McLaughlin said.
Another issue for the system is inflow and infiltration, Rundquist said. The borough and townships have a consent agreement with the Pennsylvania Department of Environmental Protection due to past instances of the plant being overloaded during heavy rains.
The borough and townships have been monitoring flow into the system, and the borough has been trying to find points of infiltration, such as cracked pipes and laterals, Rundquist said.
Last year, the borough smoke-tested about 11 miles of its 80-mile system of sewer lines, and inspected about 4.8 miles with television cameras, according to the department report. Fifty-two laterals were repaired as a result of the testing, but Rundquist said the department will survey basements to determine if property owners are illegally putting roof drain water or sump pump water into the system.
That could mitigate infiltration, but not eliminate it, Rundquist said.
"In 1911, there was no intent to make these things watertight," he said of the aging terra cotta lines in the oldest part of the system.
The department will begin replacing 1,111 feet of sewer lines along Lincoln Way East and Lincoln Way West in the near future, Rundquist said. That work will cost $569,000, he said.
The total for sewer system improvements next year is $1.2 million, he said.
The department will spend about $135,000 on equipment installation and improvements to the control tower at Long Pine Dam and another $200,000 on a 12-inch water line between Mill Road and Orchard Drive, Rundquist said.