A more resilient wastewater system for Middlesex County, NJ

Protecting the Raritan River with a robust wastewater system

Recognizing the need for continuous improvement and to enhance reliability, the New Jersey Department of Environmental Protection (NJDEP) initiated a comprehensive assessment of the Middlesex County Utilities Authority (MCUA) wastewater management system.

As part of these efforts, the MCUA would upgrade the Edison Pump Station, which conveys 22 million gallons per day (MGD) (83,000 cubic meters per day) to the MCUA’s Central Treatment Plant. Located near the Raritan River, the pump station is designed to significantly improve the efficiency and capacity of the wastewater treatment system.

Modernizing the Edison Pump Station

The MCUA engaged Mott MacDonald to provide design and construction management and oversight for a complete rehabilitation and replacement of the Edison Pump Station. The project scope included the following:

• Complete replacement of all five existing 400-horsepower, 24-inch pumps with new 500-horsepower, 30-inch pumps
• Replacement of all associated valves
• Replacement of main control panel with modern PLC-based controls incorporated into a SCADA network
• Replacement of all existing motor starters with new variable-frequency drives
• Installation of natural-gas-fired generators and associated distribution switchgear to allow 2.5 megawatts of standby emergency power in parallel with utility power

The new electrical system reduced operating voltage from 34.5-kilovolt utility power to 480-volt distribution, providing safer conditions for personnel. A pump conditioning panel monitors each pump's temperature and vibration status, making proactive maintenance possible. The project also provided the MCUA with modern control systems optimizing the use of new, efficient pumps for multiple force mains – resulting in increased reliability and energy cost savings.  

Enhanced resilience in Middlesex County’s wastewater system

The improvements to the Edison Pump Station have made the MCUA’s wastewater system more resilient, protecting the health of Middlesex County residents and the integrity of the local environment.