Mattawoman WWTP, Waldorf, Maryland: Large-Scale Wastewater Treatment in the Chesapeake Bay Watershed

Mattawoman WWTP is a municipal wastewater treatment facility located in Waldorf, Charles County, Maryland, United States. It serves a population of approximately 90,111, placing it in the large agglomeration category under US EPA guidelines. The plant is situated near the Potomac River, which ultimately drains into the Chesapeake Bay. As a US facility of this scale, Mattawoman WWTP operates under the Clean Water Act and is subject to National Pollutant Discharge Elimination System (NPDES) permitting. Plants serving populations over 50,000 typically employ advanced secondary or tertiary treatment to meet stringent nutrient removal requirements, particularly in the Chesapeake Bay watershed where nitrogen and phosphorus limits are enforced. The plant's discharge enters the Potomac River, a major tributary of the Chesapeake Bay. The Chesapeake Bay is the largest estuary in the United States and supports diverse aquatic life, including blue crabs, oysters, and migratory fish. The plant's location within 50 km of the coast means its effluent contributes to the nutrient load in the bay, making advanced treatment critical for ecosystem health.

Mattawoman WWTP discharges into the Potomac River, which flows into the Chesapeake Bay, a large estuary on the Atlantic coast. The Chesapeake Bay watershed is ecologically sensitive, supporting diverse species such as striped bass, blue crabs, and submerged aquatic vegetation. Nutrient pollution from wastewater is a key concern, driving regulatory programs like the Chesapeake Bay Total Maximum Daily Load (TMDL) to reduce nitrogen and phosphorus inputs.