Patapsco WWTP Chlorine Contact Chamber Rehabilitation

Originally constructed in 1940, the Patapsco Wastewater Treatment Plant (WWTP) is part of the City of Baltimore’s critical water infrastructure. The plant has a capacity of 63 million gallons per day and serves an area of approximately 184 square miles.

One of the last steps in the wastewater treatment process at Patapsco is chlorinating the wastewater in four different chambers. The chamber basins had deteriorated severely over time, and the chambers also showed signs of baffle wall failures and mechanical equipment corrosion—in all, a recipe for a potential disaster.

The City undertook a repair and rehabilitation project that included repairing and finishing more than 160,000 square feet of concrete surface and then coating it with a chemical resistant epoxy. EBA inspected the four chlorine contact chambers to identify structural defects and selected repair techniques and materials to stabilize the concrete, reconstruct the baffle walls, and replace the mechanical and metal fixtures.

The project extended the useful life of the chambers by at least 20 years and saved the City the significant cost of demolishing and reconstructing the chamber walls and floors. Seamless cooperation between the owner, engineer, manufacturer, and contractor resulted in a successful project that met all the client’s goals.