News Sustainability Environment
Wastewater facility’s upgrades will reduce greenhouse gas emissions

Energy-efficient improvements to a wastewater treatment facility in Hersey, Pa. are being designed to ensure it significantly reduces greenhouse gas emissions via biogas recycling.

Brown and Caldwell, an environmental engineering and construction firm, has been selected by the Derry Township Municipal Authority (DTMA) to design the proposed improvements at the Clearwater Road Wastewater Treatment Facility.

Already accepting organic waste from third-party carriers, the authority is developing long-range plans to maximize the capability to receive additional organic wastes. Facility upgrades are considered key to expanding capacity and increasing energy efficiency, thus evolving the 5.02 million gallons per day facility into a more sustainable operation.

Under DTMA’s $15-million energy enhancement program at the WWTF, Brown and Caldwell will lead the design of a combined heat and power facility capable of burning biogas that will power two generator engines. After pairing with a new gas conditioning system for high-quality fuel production, the combined heat and power facility will integrate into the WWTF’s existing electrical and heating system to provide electricity and heat throughout. Brown and Caldwell will assist DTMA with the procurement of the engines through COSTARS, the Commonwealth of Pennsylvania’s cooperative purchasing program.

Other improvements include a conveyance system to transport gas throughout the facility, sludge blending tank enhancements to maximize energy recovery via biogas generation, and secondary digester modifications for future conversion to a primary digester.

“Increasing the production and beneficial use of anaerobic digester biogas as our fuel source to provide power and heat is significantly more efficient and environmentally sustainable than using electrical power from the grid or fossil fuels,” DTMA executive director Wayne Schutz said. “The authority has a strong interest in fully reusing our resources, and this project meets numerous objectives within DTMA’s core values to maintain and improve our facilities without impacting our ratepayers while propelling future sustainability.”

A multi-disciplinary team led by Brown and Caldwell includes RK&K, which will provide electrical and instrumentation expertise, and Bassett Engineering, which will assist with permitting, site design, and stormwater control.

Upon completion of improvements, the WWTF will increase biogas power generation to 1,600 kilowatts per hour from 280, significantly reducing the facility’s carbon footprint.

“We applaud DTMA for embarking on this important program to promote sustainability within the township,” Brown and Caldwell project manager Colin O’Brien said. “Brown and Caldwell is honoured to play a key role in transforming the facility and joining DTMA on its journey to becoming a more sustainable, green community.”

The design phase of the project will run through May 2020, with construction scheduled to begin by fall 2020.