The primary historic industrial contamination in the Gowanus Canal is coal tar from three manufactured gas plants. US Environmental Protection Agency (EPA) and the Potentially Responsible Parties (PRPs) are working to design and coordinate dredging on average 10’ of heavily contaminated sediment from the bottom of the Gowanus Canal and construct a multi-layer cap.

Pilot testing for dredging practices are currently complete at the 4th Street Turning Basin, as are is the pilot to cap the bottom to prevent more contamination from seeping into the water. Next, bulkheads will be rebuilt at the north end of the Gowanus Canal before dredging can begin there.

Sewage Infrastructure Update

On September 20, 2019, the U.S. Environmental Protection Agency (EPA) Region 2 delivered a letter to the NYC Department of Environmental Protection (DEP) rejecting the City’s proposal for the first combined sewage overflow (CSO) tunnel in NYC to be built below the Gowanus Canal, instead of the two tanks previously proposed. The EPA then attended the Gowanus Canal Community Advisory Group (CAG) Meeting on September 24 to discuss the decision.

In their letter to the DEP, the EPA comments that the tunnel proposal could pose unforeseen risks and delay progress on the agreed-upon Superfund schedule, thus increasing the duration of risks to human health and the environment. 

A major benefit of the tunnel proposal was that it would manage more CSO than the tanks. In their letter to the DEP, the EPA states that “EPA believes that there are other potentially viable options for the City to address its infrastructure needs outside of the Superfund remedy process.” At the recent Gowanus Canal CAG meeting, EPA expressed their commitment to working with the City and the community to coordinate efforts on the rezoning to improve infrastructure and address issues of flooding and resiliency. Gowanus Canal Conservancy (GCC) is ready and eager to support this coordination with mitigation strategies for new development to ensure the rezoning doesn’t add additional CSOs.

GCC believes the rezoning must achieve Net Zero CSO into the Gowanus Canal, and this can be achieved with the appropriate policies and commitment from the City and developers – see more details here.

The decision to reject the tunnel proposal and move forward with the tank proposal unfortunately took a long time, but GCC is looking forward to moving forward. The 90% design for the first tank (at the head of the Gowanus Canal) will be presented at the Gowanus Canal CAG’s October meeting, and we look forward to it coming online to begin managing nearly 90 million gallons of CSO per year. We also eagerly await the next steps on the second tank at the Salt Lot.

Read the full letter from the EPA.


Learn more

Gowanus Canal Community Advisory Group (CAG)
EPA Gowanus Canal Superfund Site