Drainage Upgrade at NYCHA's Throggs Neck Houses Reduces Flooding and Improves the Health of the East River

August 16, 2021

Subsurface drainage chambers capture nearly 2 million gallons of stormwater annually; before and after photos available on DEP’s Flickr page

The New York City Department of Environmental Protection (DEP) today announced the completion of a $1.3 million drainage upgrade at the New York City Housing Authority’s (NYCHA) Throggs Neck Houses. The project included the construction of two subsurface stormwater drainage chambers that will capture nearly 2 million gallons of stormwater in a typical year. By capturing the stormwater that falls on the development and keeping it out of the sewer system, the project will ease pressure on the neighborhood’s drainage system during rainstorms, which will decrease flooding and any overflows into the upper East River.

“By upgrading the drainage facilities at NYCHA’s Throggs Neck Houses we will continue the important work of improving the health of the East River while also improving services for residents,” said DEP Commissioner Vincent Sapienza. “We look forward to continuing this critical partnership with NYCHA in order to provide the same drainage and landscaping improvements at other development across the five boroughs.”

One of the subsurface drainage chambers was built beneath a parking lot, which was completely resurfaced. The second drainage chamber was built under a low-point where several walkways converge. In addition, DEP repaired a drain in an adjacent parking lot and resurfaced a portion of the lot to create the correct pitch and ensure proper drainage. The subsurface installations allow stormwater to be absorbed naturally into the ground, minimize ponding and keep stormwater from entering the sewer system, where it would otherwise contribute to overflows into the upper East River.

DEP manages New York City’s water supply, providing approximately 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 has a robust capital program, with a planned $20.1 billion in investments over the next 10 years that will create up to 3,000 construction-related jobs per year. For more information, visit nyc.gov/dep, like us on Facebook, or follow us on Twitter.