New York City’s subway—much of it more than a century old and largely underground—is increasingly exposed to heavier downpours and hotter summer conditions. Recent flooding has repeatedly disrupted service, prompting officials to accelerate climate-resilience plans that transit leaders say will require billions of dollars in long-term investment.
New York City’s largely underground subway system—one of the oldest in the United States—is becoming more vulnerable as climate change increases the odds of intense rainfall and extreme heat.
Two months before Zohran Mamdani was sworn in as mayor in a private, just-after-midnight ceremony on January 1, 2026 at the decommissioned Old City Hall subway station, a record rainfall event flooded stations across the city, sending dramatic videos online that showed water pouring into stations and cascading down stairways. In July, separate videos of riders climbing out of a submerged station spread widely on social media.
The climate threats are not limited to heavy rain. Riders also contend with stifling summer conditions in some stations, where limited ventilation can amplify heat during hot days.
In August, Gov. Kathy Hochul ordered an investigation into the transit system’s climate vulnerability, underscoring officials’ concerns that the subway’s design and geography leave it exposed as downpours intensify, sea levels rise, and coastal erosion worsens.
The MTA’s push to harden the system accelerated after Superstorm Sandy in 2012, when the agency installed coastal surge protections at 31 subway stations. But recent floods have highlighted ongoing risks, including the possibility of injuries or deaths in extreme events—an outcome seen in other countries, including China’s deadly 2021 subway flooding.
The agency’s Climate Resilience Roadmap, released in April 2024, lays out 10 resilience goals, including efforts to shield stations and tunnels from stormwater and to improve underground air circulation and cooling. The MTA’s initial estimate for the capital work described in the roadmap totals more than $6 billion over a decade.
The MTA has said its latest capital plan supports $1.5 billion in climate-resilience investments, including $700 million dedicated to stormwater flood-mitigation work—such as upgrading pump rooms that move water out of the subway and into the city’s sewer system. New York State’s comptroller has reported that, as of 2023, 11% of those pump rooms were in marginal or poor condition.
Some measures are already visible at street level. The MTA has added elevated steps at certain entrances—such as at the 28th Street station in Chelsea—to help prevent rainwater from spilling directly into stations. The agency has also sealed some manholes that previously sent water surging upward during heavy rain, and it has elevated some drains and expanded drainage improvements.
The MTA has identified 10 priority locations across all five boroughs as especially prone to storm-flooding risks and has urged additional protections in those areas.
City officials say the pace of upgrades needs to match the speed of the changing climate. Louise Yeung, the city’s chief climate officer, has described New York as racing against “a climate system that is changing very rapidly,” adding that the city must keep “catching up with the speed at which the climate is changing.”
Transit leaders say they are looking abroad for ideas, drawing lessons from newer systems such as Copenhagen’s Metro and older networks such as London’s Tube and Paris’s Métro. Eric Wilson, an MTA senior vice president overseeing climate strategy and land-use issues, has said the agency’s goal is continuity of service even during extreme weather.
Advocates also emphasize transit’s climate benefits. Kara Gurl of the Permanent Citizens’ Advisory Council has argued that “Transit is the antidote to climate change,” citing MTA estimates that regional transit riders avoid at least 20 million metric tons of greenhouse gas emissions annually—an amount the MTA compares to the carbon absorbed by a forest the size of Indiana.
At the same time, regional planners warn the impacts of both climate change and the fixes will not be evenly felt. Tiffany-Ann Taylor of the Regional Plan Association has said inequity remains a factor in how resilience investments are prioritized and implemented.
The stakes can be significant. The Associated Press has previously estimated that a 2015 shutdown of public transit for less than a day during a snowstorm cost the city roughly $200 million in lost economic activity—an example often cited by transit officials and advocates as they argue that preventing service disruptions can carry large economic benefits.
Federal policy and funding uncertainty could complicate the long buildout of resilience projects. Still, local officials say New York intends to move forward with measures it can control—ranging from basic sewer and street repairs that affect station flooding to exploring emerging technologies, including geothermal approaches to cooling and heat management.
