Buffalo Township supervisors approved the site plan for the expansion of the township’s sewage treatment plant.

Engineers for the Municipal Authority of Buffalo Township presented the plans to the supervisors at their May meeting.

Matthew Sprung and Doug Siler of Gibson-Thomas Engineering said the proposed expansion of the plant at 161 Monroe Road is projected to cost $14 million.

Siler said the expansion is necessary because the plant is nearing the limit of its current treatment capacity.

He said that is a result of all the business and residential development that has taken place in the township in recent years.

Township engineer Ken Howard said he reviewed the plans and recommended the supervisors approve the project.

With the expansion, Siller and Sprung said the plant’s current capacity of just under 1 million gallons of sewage per day will expand to 1.3 million gallons per day.

With the expansion, the treatment plant will bracket the Butler-Freeport Community Trail.

“The current plant is south of the trail,” Sprung said. “The expansion will all be on the northern side.”

The project will include a new equipment building, a new sewage sludge holding tank, two new aeration tanks and a new clarifier.

“They will all be open-air, just like the current tanks,” Siler said.

In addition, the engineers said, the project includes the installation of 7,100 feet of new sewer main line.

Also, the engineers noted that the site plans provide land for future expansion with vacant tracts reserved for adding another clarifier and aeration tanks to handle more growth in the township.

Sprung said the authority will be applying to PennVEST for state financing of the project.

If all goes well, he said, construction of the plant expansion will start around this time next year and will take about 18 months to complete.