March 25, 2025

Work Finished 6 Months Ahead of Schedule

Project Will Create New Public Open Space in Brooklyn; Keep Mixed Sewage from Overflowing into the Gowanus Canal During Storms

The New York City Department of Environmental Protection (DEP) today announced the early completion of excavation for an 8-million-gallon underground tank that will intercept and store combined sewage that would otherwise overflow into the Gowanus Canal during rainstorms. DEP safely delivered this critical milestone six months ahead of schedule by implementing an accelerated construction plan in December 2024.

DEP broke ground on the project in March 2023 with an aggressive schedule agreed upon with the U.S. Environmental Protection Agency’s (EPA), which has oversight of the project under the Superfund program. A second tank, located at the bend of the Gowanus Canal at 2^nd Avenue and 5^th Street, is also under construction. When the two tanks are completed, the canal will be cleaner and healthier, and the top of the tanks will be transformed to provide 3.6-acres of public waterfront open space for the community.

“We are tremendously proud to have completed the excavation for the 8-million-gallon tank ahead of schedule, an achievement that is a testament to the dedication of everyone involved in this important project,” said DEP Commissioner Rohit T. Aggarwala. “The creativity and innovation to speed up this stage of work demonstrates DEP’s commitment to the Gowanus community. As construction progresses, we remain focused on minimizing disruptions and ensuring the safety and well-being of the surrounding neighborhood.”

“I’m so glad that the excavation for the Gowanus CSO tank is complete. This marks a significant step forward toward a cleaner, healthier Gowanus Canal for the community and the city at large. I’m grateful to the DEP for this enormous undertaking and their dedication to this project,” said Assemblymember Jo Anne Simon.

“I am thrilled that the New York City Department of Environmental Protection has completed this phase of the Combined Sewer Overflow Facilities Project for the Gowanus Canal ahead of schedule,” said Congressman Dan Goldman. “As we face more extreme weather events, it is crucial that we continue to prioritize the environmental protection of our communities. The CSO project currently under construction will play a vital role in safeguarding residents by managing sewage overflow. Those who reside near the Gowanus Canal deserve our unwavering commitment to improving the safety and health of their environment.”

“Corporations of the past treated the Gowanus Canal as a dumping ground and left New Yorkers with the bill. But today, we’re taking an important step toward charting a new future for this waterway and this neighborhood,” said State Senator Andrew Gounardes. “This important project will capture millions of gallons of sewage that would otherwise flow into the Canal during storms, keeping our neighborhood cleaner, safer and more resilient. Plus, the project will create new open space for neighbors and families to enjoy. This is how we create a greener, more livable Brooklyn.”

“The completion of the excavation for the Gowanus CSO Tank facility marks a significant milestone for our community, and I’m proud that we are moving on to the construction phase,” said Council Member Shahana Hanif. “As work begins this May and continues through the Summer of 2026, I am dedicated to working closely with the EPA, the DEC, and the DEP to provide clear, timely, and accessible updates to the community. Gowanus residents deserve a safe, clean, and livable neighborhood. My elected colleagues and I are committed to addressing constituents and ensuring that every effort is made to minimize odors, noise, and disruptions.”

“The completion of the excavation of the tank site brings us one step closer to a cleaner and greener Gowanus,” said Gowanus Canal Conservancy Executive Director Andrea Parker. “This stage was done ahead of schedule and with stringent environmental monitoring protocols, and we are optimistic for the same outcome for all the work that remains. With this milestone, we are significantly closer to better water quality in the Canal and almost two acres of shared public space along a revitalized waterfront.”

Like many areas in Gowanus, the site of the tank has historic contamination from manufactured gas plants that populated the area in the 19^th Century. To protect neighboring residents and businesses, as well as construction workers, DEP implemented real-time air quality monitoring and a robust air sampling program. Additionally, the agency put in place strategies to manage odors from soil excavation, such as tarping, spraying soil with non-toxic odor-neutralizing foam, using a misting system similar to bathroom sprays, and conducting routine odor inspections.

Ahead of the shallower mass excavation that was just completed, DEP, under guidance and direction from EPA, stepped up the air sampling program to collect data around-the-clock. DEP met regularly with the EPA, the NYS Department of Environmental Conservation, and NYS Department of Health to review the data. During this stage of excavation, there were no odor complaints or other quality of life complaints attributed to the DEP tank work site.

The next major stage of work to construct the tank within the excavated area will begin this May and continue through Summer 2026. During this next stage, concrete and rebar will be delivered to the site, using the approved truck routes to ensure minimal disturbance in the community. DEP has a team of dedicated construction community liaisons available to Gowanus residents and businesses to address questions or concerns. For more information, visit Gowanus Canal.

About DEP

DEP manages New York City’s water supply, providing more than 1 billion gallons of high-quality drinking water each day to nearly 10 million residents, including 8.8 million in New York City. The water is delivered from a watershed that extends more than 125 miles from the City, comprising 19 reservoirs and three controlled lakes. Approximately 7,000 miles of water mains, tunnels and aqueducts bring water to homes and businesses throughout the five boroughs, and 7,500 miles of sewer lines and 96 pump stations take wastewater to 14 in-city treatment plants. DEP also protects the health and safety of New Yorkers by enforcing the air and noise codes, and asbestos rules. For more information, visit nyc.gov/dep, like us on Facebook, or follow us on X, formerly known as Twitter.