The U.S. Environmental Protection Agency (EPA) has rejected a proposal by the New York City Department of Environmental Protection to clean up the Gowanus Canal with increased efficiency. The 1.8-mile-long canal in Brooklyn has long-been considered one of the nation’s most contaminated bodies of water.

The canal’s pollution can be traced back as far as the 19th century. Located in a major industrial hub, it served as an active dumping site for chemicals from the paper mills, gas plants, and leather tanneries that surrounded it. Today, the canal faces the harmful effects of combined sewer overflow (CSO), which occurs when substantial rainfall causes the sewer system to release wastewater into the canal.

Since 2010, the Gowanus Canal has been a designated Superfund site, marked by the EPA for high-priority cleanup because of contamination by hazardous waste that poses a threat to public health or the environment. As residential development continues to add luxury buildings to Gowanus, the push to save the canal has gained even more momentum. Dredging of the waterway began in the fall of 2017.

In a letter to the City, the EPA formally rejected a proposal to construct a 16-million gallon underground CSO tunnel to divert pollutants. Instead, Peter Lopez, regional administrator of the EPA, announced that the agency planned to move forward with the installation of two CSO retention tanks along the canal. Lopez cited several EPA concerns in the letter, including cost impacts, insufficient protection, and external factors outside of the agency’s federal jurisdiction. In addition to holding four million more gallons than the tanks, the tunnel’s design would have given the City the opportunity to expand it in the future if necessary.

While the EPA has remained steadfast in its plans to fix the canal, it claims that the City’s proposal was given careful consideration; the letter concluded with the following statement from Lopez:

“In terms of advising the community of this decision, we plan to concentrate our outreach to advising them that we have cooperatively reviewed the City’s proposal and focus on the many steps occurring as we move ahead with the selected remedy. We look forward to our continued, close collaboration as we work to bring the benefits of this critical work to the Gowanus community.”