Last September, New York City was so thoroughly inundated by Hurricane Ida that some commuters waded through water up to their waists just to get in and out of the subway station. Across the country, extreme heat battered the West Coast, melting Portland’s streetcar power cables. This summer is seeing similar headlines, with heatwaves warping the BART train tracks in San Francisco and sudden rainfall interrupting Northeastern commutes.

These extreme weather events, which are increasing in severity and frequency due to climate change, pose a problem to the millions of Americans who rely on public transit to get to and from work, school, the grocery store, the hospital and social events. According to Maria Sipin, a former Transportation Justice Fellow at the National Association of City Transportation Officials (NACTO), public transit is a “lifeline” for many groups of people that already face disproportionate challenges due to historic discrimination or marginalization. Disabled individuals, residents of low-income communities, and Black and Brown communities are less likely to have access to a car,more likely to live further from their jobs and tend to rely on public transit for their commutes (thanks in part to the legacy of redlining and ongoing disinvestment in minority neighborhoods). When extreme weather impacts public transit, it has the potential to deepen existing inequalities. 

It also threatens the country’s ability to meet climate goals: Transportation is responsible for 27% of U.S. carbon pollution, and public transit is a key tool for bringing those emissions down. If train and bus service is disrupted by extreme weather, people may turn to more emissions-intensive ways of getting around, creating a negative feedback loop that fuels the global temperature rise that caused the disruptions in the first place.

“Transportation is the largest source of emissions in the United States, and 85% of those come from people driving themselves in private vehicles,” says Alex Engel, senior communications manager at NACTO. 

Though switching those private rides from fossil fuel-burning cars to electric vehicles attracts a lot of attention and is poised to receive an important boost from the federal government through the Inflation Reduction Act, often-overlooked public transit will remain crucial to meeting climate goals.

 “A bus, even if it’s diesel powered, is a far better climate solution and contributes fewer emissions than a private car — even if the car is an EV,” Engel says.

So what can cities and transit agencies do to ensure that public transit remains a viable option for riders, even as climate change-induced extreme weather intensifies? The answers are as numerous as transit agencies themselves, but many point toward approaches that deliver a host of co-benefits.

Some of the most obvious solutions are structural. “Subway lines in many cities around the U.S. are very vulnerable to flooding,” says Yonah Freemark, senior research associate at the Urban Institute. This is particularly true of the New York area, where 40% of the country’s public transit riders live, according to Kate Slevin of the Regional Plan Association (RPA). That means it’s crucial to address any potential entry points where water can get into the system, whether from sea water, as New York City saw in the case of Hurricane Sandy, or from excessive rain, as in the case of Hurricane Ida. 

Since Sandy, New York has invested $2.6 billion in a wide range of permanent protective measures, including gates that can close behind subway ventilation grates and raised barriers around subway entrances — think a lip around the edge of the subway stairs that riders step over before descending — to keep water out. In the case of extreme storms, temporary measures, like inflatable dams blocking subway entrances, can also be implemented.

Though rail tends to dominate conversations about transit, just as many trips happen by bus as by train in the U.S., according to the American Public Transportation Association. From Engel’s perspective, that means that climate adaptation needs to include the construction of high quality bus shelters that shield riders from the elements in extreme heat and storms.

Sipin adds that ensuring equitable access to public transit also means ensuring that infrastructure leading to and from train stations or bus stops is accessible and well-maintained. When sidewalks are poorly paved, curb ramps are deprioritized and bike lanes aren’t protected, riders who need public transit the most — the vision-impaired, wheelchair users, or anyone who lives far from the places they need to go — may be unable to get to and from public transit stations safely.

“I think that often gets overlooked, because transit and walking and biking and wheelchair use are not always addressed together in tandem,” Sipin notes. “It might not seem that sexy or innovative, but those basic investments really help.”

Of course, all these measures cost money, and Freemark notes that adequate funding is a significant barrier to the buildout of climate-resilient infrastructure. Slevin highlights New York’s planned congestion pricing program, which, once implemented, will charge motorists a toll to enter Manhattan’s most crowded streets and use the money to fund MTA repairs, as one approach to addressing the issue of limited funds.

“The congestion pricing plan would raise a billion dollars annually, and 100% of that revenue would go back into the transit system,” Slevin says. 

Other cities have adopted different approaches. Rob Freudenberg, RPA’s VP of energy and environment, describes Philadelphia, which gets an average of 47 inches of rainfall per year, as a leader in dealing with stormwater. Part of the city’s strategy is billing properties for stormwater management, he notes. In addition to giving the city extra cash to deal with the issue, developers are incentivized to incorporate green infrastructure and water storage into their building designs through exemptions and discounts, helping to reduce the problem from the outset.

Planting trees, constructing bioswales (which uses landscaping to soak up storm runoff) and otherwise greening streets can also help with public transit flooding, as vegetation and soil absorb water that concrete can’t. And while extreme heat tends to require different management than flooding does, greening streets offers a solution in both cases: Shade from vegetation can reduce temperatures by as much as 45 degrees F, according to the EPA. A temperature difference that big could have kept San Francisco’s BART train from partially derailing due to extreme heat this summer. And where planting a tree canopy isn’t possible to reduce temperatures, other solutions, like painting train tracks white to deflect heat, may be.

Slevin notes that the most robust solutions won’t be executed by one agency alone. A transit agency is going to be better able to keep the subway from flooding if the sanitation department is keeping drains clear of debris and if the parks department is maximizing park land’s ability to soak up excess water, and so on.

“There is a coordination that is required to address this challenge, because it’s all interconnected,” she says. 

But the upside is that solutions can be interconnected, too. Congestion pricing can infuse money into a cash-strapped transit system while also reducing air pollution and traffic. Greening streets can lower temperatures, absorb excess floodwater and improve air quality. Climate-resilient bus shelters can make riding the bus more comfortable. And all of the above—whatever makes public transit safer, more accessible or more enjoyable to use—ultimately helps fight climate change.

“It is pretty astounding how much you can reduce emissions by making transit a more convenient option,” says Engel.


This article is co-published with Next City and made possible by a grant from the Open Society Foundations. Nexus Media News is an editorially independent, nonprofit news service covering climate change. Follow us @NexusMediaNews.