Wastewater Treatment Plant
Since 1976, when the Township established public sewer service in town, we have been working together with the Borough of Palmyra to treat wastewater from residents' homes. After a half-century of service and various changes to state and federal regulations, the Borough of Palmyra Wastewater Treatment Plant (WWTP) could no longer meet the demand and growth of the area. Therefore, North Londonderry Township swapped responsibilities with the Borough of Palmyra and began construction on a $15 million project to improve treatment and expand capacity in April 2011. This not only provided the area with a new WWTP, but the construction of two interceptor lines redirected flow and eliminated two pump stations, saving thousands in operation and maintenance fees.
Built on about 17 acres of former Millard farm land in South Annville Township, the North Londonderry Township Wastewater Treatment Plant is currently treating 900,000 gallons of wastewater a day from residential, commercial and industrial sources. At capacity, it will handle up to 1.5 million gallons/day (MGD), which leaves room for wastewater from an additional 1,500 homes. The Borough of Palmyra pays their share of fees, based upon usage, which can amount to 43% of total plant flow. Due to its location within the community, special attention was given to keep the plant out of sight. Laid out around an existing fieldstone barn and 20 large 80-year-old sycamore trees, the treatment works are set up on a hill behind a new garage and administration building for partial concealment and limiting the amount of storm run-off that enters the treatment process.
Innovative construction features include passive solar lighting, space for the future use of solar panels on every building, the use of effluent (treated water leaving the plant) to heat and cool buildings, insulated concrete block and metal roofing that will last longer than traditional asphalt shingles. The new garage utilizes an infrared heating system and automated equipment minimizes staffing requirements. The self-regulating equipment monitors its own operating conditions and notifies staff if a parameter goes out of range as well as only running what equipment is necessary thus, saving energy.
How does a treatment plant work?
Filters remove plastic, grease and paper from sewage transported via the collection system to the plant. Sewage then flows to two 1.3 million gallon tanks, where natural bacteria digest and decompose any biosolids with the assistance of aeration - by way of a revolving arm - and water. Two smaller clarifier tanks will then separate the liquids from the solids and send the liquid to a filter building where it will be disinfected with ultraviolet light and chlorine. On average, 900,000 gallons of effluent is returned to Killinger Creek every day. But wait, what happened to the solids? They are dried and reduced down to 20% matter creating 200-250 tons of matter per year that is either spread onto farmland or transported to the county landfill. Over the winter, when it can't be applied to farmland, there is storage space for 90 days' worth of biosolids.
The new plant operates with four employees, all certified DEP Wastewater Operators, compared to nine utilized by the age old Borough of Palmyra plant and collection system maintenance is handled by the North Londonderry Township Highway Department. We have our own full-time DEP accredited lab that tests the successes of plant processes in treating sewage before its ultimate elimination into the surrounding environment. Annual operating cost is budgeted at $1.4 million.