Kilmarnock STP - Secondary Wastewater Treatment in Northumberland County, Virginia

Kilmarnock STP is a municipal wastewater treatment facility located in Northumberland County, Virginia, on the Northern Neck peninsula. The plant serves a small community of approximately 1,350 residents, providing secondary treatment to remove organic matter and suspended solids from domestic wastewater. The plant has a designed capacity of 1,892.70 megaliters per year and currently treats an average daily flow of 416.40 megaliters per year. As a secondary treatment facility, it meets the minimum requirements under the U.S. Clean Water Act for municipal wastewater treatment. The plant is operated under a National Pollutant Discharge Elimination System (NPDES) permit issued by the Virginia Department of Environmental Quality, which sets effluent limits to protect water quality. The treated effluent from Kilmarnock STP discharges into local waterways that ultimately drain into the Chesapeake Bay, the largest estuary in the United States. The Chesapeake Bay watershed is ecologically sensitive, supporting diverse aquatic life including oysters, blue crabs, and striped bass. Nutrient removal from wastewater is critical to reducing algal blooms and hypoxia in the Bay.

Kilmarnock STP discharges into the Chesapeake Bay watershed, a vast estuary system that drains parts of six states. The Bay is a critical habitat for fish, shellfish, and migratory birds, but suffers from nutrient pollution. Secondary treatment provides basic nutrient removal, but the plant's location within 10 km of the coast means its discharge can quickly reach sensitive tidal waters.