To: NYC Department of Environmental Protection

From: Nick Siguiera, Jaidon Soto, Santiago Rodriguez Solano

Date: 06/12/2026

Subject: Proposal for Smart Permeable Pavement in Flood-Prone NYC Neighborhoods

Introduction

New York City has experienced more frequent and intense rainstorms in recent years. According to the New York State Climate Impacts Assessment, total annual precipitation in New York has already increased by about 10% to 20% from 1901 to 2022, and it is projected to increase another “6% to 17% by the end of the century,” with some of the largest increases expected in New York City and the surrounding region (New York State Climate Impacts Assessment [NYSCIA], 2022). Heavy rainstorms that lead to flooding are also projected to become more frequent. This is a serious issue because much of the city relies on aging sewer infrastructure and a large amount of pavement that does not absorb water well.

Problem

These more intense rainstorms and increased levels of precipitation are leading to significant floods throughout the city. One of the most visible effects of flooding is disruption to the subway system. CBS News New York reported that even one strong rainstorm can put parts of the subway system underwater, sending riders scrambling and making some commuters nervous about being trapped underground (Brennan, 2025). These concerns are not only about comfort or delays. When stations and platforms flood, people can be late to work or school, businesses can lose money, and riders can be exposed to unsafe or contaminated water.

The problem is also difficult because the subway and sewer systems are connected to what happens above ground. CBS News noted that the MTA is already trying to raise vents, add steps at entrances, and seal openings above street level, but some stations are below the water table and the city is already pumping about 10 million gallons of water each day into the sewer system. When that system backs up during heavy rain, the flooding becomes much harder to control (Brennan, 2025). This shows why the city needs more surface-level stormwater solutions instead of only relying on underground drainage.

Solution

A realistic solution is for NYC to expand the use of smart permeable pavement in neighborhoods that flood the most. Permeable pavement is a porous surface that allows rainwater to pass through instead of immediately running across the street. The water can then move into the soil, an underground stone bed, or a drainage system. A recent civil engineering study on permeable pavement explains that these systems help reduce surface runoff, support groundwater recharge, and improve urban stormwater management (Davis et al., 2025). The study also discusses newer pavement designs such as PurePave, a polyurethane-based permeable pavement, as an example of how the technology is continuing to improve for sponge-city style stormwater management.

This should not be treated as a full replacement for the sewer system, but as something that can help reduce the amount of stormwater reaching streets and subway entrances at once. NYC could start with areas that suffer the most from poor stormwater drainage, especially parts of South Brooklyn and South Queens, along with streets near major subway stations, bus stops, and schools. If installed in the right places, permeable pavement could slow down runoff and make flooding less severe during heavy storms.

There are still things to consider with this solution. The pores in permeable pavement can become clogged over time with trash. The same civil engineering study notes that clogging is one of the main challenges because it can reduce the pavement’s ability to absorb water over time (Davis et al., 2025). Also, areas with extremely heavy traffic may wear down faster, so the city should focus first on sidewalks and lower-traffic streets instead of major truck routes. Regular cleaning and inspections would be necessary for the system to keep working.

Recommendation

New York City should begin a phased pilot program that installs smart permeable pavement in neighborhoods that experience frequent street and transit flooding. The city should prioritize low-lying streets, areas near subway entrances, and blocks where stormwater regularly collects. The pilot should include regular maintenance and comparisons between flood-prone blocks with and without the pavement.

A phased approach would allow the city to test this solution, measure results, and expand it into other flood-prone neighborhoods if it works.