KNSG Wastewater Treatment Plant

Kent Narrows, Stevensville & Grasonville Wastewater Treatment Facility


The Kent Narrows / Grasonville / Stevensville (KNSG) wastewater service area was constructed in 1979 -1982 with federal and state grant funds to service areas with failing septic systems. The service area extended along US Route 50 / 301 from Hess Road in Grasonville to Maryland Route 8 on Kent Island. The collection system selected utilized vacuum collection which was considered innovative at the time. This system was selected due to the flat land surfaces, and high water tables, inherit in the service area. The selection of an innovative system also maximized grant participation.

Water Volume & Processing

The wastewater treatment plant was located just off the shore of the Chesapeake Bay, was sized to treat 800,000 gallons per day, and consisted of secondary treatment designed to achieve Biological Oxygen Demand (BOD) removal utilizing the Rotating Biological Contactor (RBC) process. This plant was shortly thereafter rerated at 1,000,000 gallons per day due to its superior operating characteristics.


In 1986, a second 1 million gallon per day RBC train was added. This expansion also included phosphorus removal. Phosphorus is one of 2 nutrients identified as being responsible for excess algae in the Bay.

In 2007 construction was completed to replace the 2 million gallon per day facility with a new 3 million gallon per day advanced tertiary treatment plant utilizing the activated sludge process. This new process is required to remove nitrogen, the second damaging nutrient, responsible for excess algae in the Bay.