At a Glance

  • New York City announced a $68 million investment to build the borough's first Bluebelt system in Brooklyn's Prospect Park, using nature-based solutions to reduce flash flooding. The announcement was made by Mayor Eric Adams last week.
  • The plan includes upgrading drainage infrastructure at Prospect Park Lake to lower water levels within 36 hours, and creating new ponds and rain gardens to collect stormwater.
  • According to the New York City Panel on Climate Change, average annual rainfall in the city is projected to increase by up to 14% by the 2050s and up to 22% by the 2080s, with the number of extreme rainfall events also expected to rise.

In-Depth Analysis

According to the Fifth National Climate Assessment, extreme rainfall in New York City and the entire Northeast has increased by about 60% since the 1950s. Adams said in a statement that the Bluebelt system will provide a solution for "better managing heavy rainfall."

In July of this year, two slow-moving storms brought heavy rain to the city, causing evacuations and transportation and road closures. On October 30, another record-breaking downpour caused more damage and resulted in two deaths. A spokesperson for the Department of Environmental Protection said in a statement that the October storm "continued the pattern of short but intense heavy rainfall that has become increasingly common in recent years."

The Prospect Park Bluebelt project is the result of a year-long study by the Department of Environmental Protection on flooding issues in Brooklyn neighborhoods around the park and the paths of stormwater flow within the park. The study found that during heavy rainfall, water tends to flow quickly across the ground rather than entering the 60-acre lake, causing flooding. Additionally, the lake's limited capacity to absorb floodwater could lead to overflow, putting stress on the sewer system.

The Department of Environmental Protection, NYC Parks, and the Prospect Park Alliance will collaborate to upgrade the lake's drainage infrastructure, create a new pond and a continuous rain garden to slow water flow and filter pollutants before they enter the lake, and restore a previously filled-in pond north of the Prospect Park Zoo to collect stormwater from Flatbush Avenue.

The project is designed to complement a $20 million shoreline restoration plan that will rebuild the shoreline of Prospect Park Lake with green infrastructure for stormwater management.

NYC Parks Commissioner Iris Rodriguez-Rosa said in a statement that public parks can serve as "natural infrastructure to make our city more resilient."

"By harnessing Prospect Park to manage stormwater, we are transforming one of Brooklyn's most cherished public spaces into a powerful tool against climate change," said Department of Environmental Protection Commissioner Rohit Aggarwala in a statement.

The first Bluebelt system in New York City was completed on Staten Island in 2023. According to a press release, the $110 million project drains and naturally filters stormwater into catch basins and storm sewers before discharging into Lower New York Bay.

According to the World Economic Forum, nature-based solutions using "green and blue infrastructure" such as trees, grasslands, and ponds cost on average 50% less than engineered solutions and deliver 28% additional value.

According to Atlantic International University, cities that use wetlands and rain gardens to absorb water and prevent runoff—known as the "sponge city" concept—are gaining attention as a measure to combat urban flooding.