Back River Wastewater Treatment Plant

The Back River Wastewater Treatment Plant (BRWWTP) began construction in 1907 and was opened in 1911. It is owned and operated by the City of Baltimore. It is situated on the west shore of the Back River; a tributary of the Chesapeake Bay. The plant occupies a 466-acre site and has a 35-foot elevation difference from influent to outfall, allowing wastewater to flow through the plant entirely by gravity. An estimated 1.3 million residents in a 140 square mile area of Baltimore City and County are served by this plant.

The BRWWTP currently employs approximately 300 people, including supervisory, operations, maintenance, and laboratory personnel. Twenty-four-hour, year-round plant operation is maintained. Our facility has evolved into a tertiary treatment plant and is currently designed to treat 180 million gallons per day (MGD) of wastewater utilizing fine bubbles, air distributed activated sludge. Utilizing phosphorus control by chemical addition and nitrogen control by biological processes, we currently remove a majority of these nutrients. Hydraulically, the BRWWTP can handle peak flows of over 400 MGD.

Wastewater from both Baltimore City and County enters the Back River plant through two large conduits. At the plant’s Influent Metering Building, flow rates are measured by two 78-inch diameter magnetic flow meters. After treatment, as described in the following paragraphs, approximately forty percent of the final effluent is diverted through two 6-mile long pipelines to Severstal Corporation at Sparrows Point for industrial purposes. The remaining effluent passes through a 1,200-foot long outfall structure where it is gradually aerated and diffused into Back River.