When the Town of Hurlock, Maryland, upgraded its wastewater treatment plant to meet new effluent limits, the project cost $7.5 million and operating costs went up. Today, the plant is saving money through renewable energy and more efficient equipment.A solar photovoltaic system activated last September will help, as will new high-efficiency blowers being phased in to reduce electricity demand.Ten years ago, Hurlock replaced its 2 mgd lagoon plant with a 1.65 mgd four-stage Bardenpho activated sludge facility with enhanced nutrient removal to meet effluent standards of the multistate Chesapeake Bay Watershed Agreement. Maryland set a nitrogen limit of 4 mg/L,
