Extreme Weather Is Soaking New York City. Community Gardens Can Help.

The wooden shed in a community garden in northern Manhattan is not just for storing rakes, hoes and shovels.

It is also playing a small part in fortifying New York City against the devastating storms that have flooded its streets and buildings and overloaded its sewer system.

Rainwater rolls down the shed’s corrugated steel roof into a white pipe that connects to a large plastic tank. The setup, which was installed last year at the Mobilization for Change Community Garden in Upper Manhattan, captures up to 2,000 gallons of storm water runoff a year that would otherwise flow through the city.

“The water was just running away from us,” said Adem Clemons, 41, a financial technology engineer who now sprinkles the captured rainwater on tomatoes, squash, peppers and rosemary in his garden plot.

New York’s network of more than 550 community gardens has long been a refuge for cramped apartment dwellers, offering space to grow fresh vegetables and soak up sun and fresh air. Increasingly, they have also become neighborhood outposts in the city’s efforts to control flooding.

Many have added rain gardens and bioswales (trenches with vegetation designed to absorb water), and collected water from sheds, gazebos, pergolas and even the rooftops of neighboring buildings with “rainwater harvesting systems” like the one installed at Mobilization for Change.

An estimated 165 million gallons of storm water are diverted from the city’s streets and sewer system every year because of community gardens, according to Earthjustice, an environmental law nonprofit, which based that figure on a 2016 analysis published in a scientific journal.

Advocates like Earthjustice are pushing for broader recognition of the gardens’ ability to divert rainwater, especially after last year’s Hurricane Ida unleashed flooding that killed New Yorkers trapped in basement apartments, paralyzed streets and neighborhoods, and poured into subway stations.

“Community gardens are part of the solution because they are a permeable space in a city that is full of impermeable surfaces,” said Mike Rezny, the assistant director of green space for GrowNYC, a nonprofit that has worked with community gardens to build 115 rainwater collection systems since 2002.

Still, the city needs impermeable surfaces too, including affordable housing. While both rents and extreme weather seem to be on the rise, government officials, as well as housing and environmental advocates, are engaged in a delicate balancing act to prioritize both.

“It’s not about stopping development and it’s definitely not about stopping affordable housing,” said Alexis Andiman, a senior attorney for Earthjustice. “It’s about recognizing that if you cover every green space with development, you end up with communities that really aren’t livable.”

The situation at the Pleasant Village Community Garden in East Harlem illustrates the tensions that can arise between housing and environmental needs. It has been around since 1978, when residents decided to haul away rubble from a site where buildings had been burned down. They then threw “seed bombs,” or packs of mud with seeds, said Kim Yim, the president of the garden.

These days, it has 60 members who tend apple, pear and peach trees, grow vegetables in 40 individual plots and collect eggs from a chicken coop. The members put in native pollinator plants to absorb rainwater that flows down to the street. During the pandemic, they composted over 10 tons of food scraps from the neighborhood.

But this fall, they will have to vacate the part of the garden that sits on city-owned land, which is overseen by the Department of Housing Preservation and Development, in order for affordable housing to be built there. “We shouldn’t have to pick one initiative or another,” Ms. Yim said. “They shouldn’t be pitted against one another because they’re both necessary.”

City officials said that affordable housing was desperately needed in that neighborhood, and that the new building will include measures to reduce storm water runoff because the area is prone to flooding.

In an effort to protect community gardens from development, more than 70 groups have petitioned city officials to designate the green spaces as “critical environmental areas” under state law.

The campaign grew out of a student project at the Pratt Institute, where Raymond Figueroa Jr., the president of the New York City Community Garden Coalition is a faculty member. Mr. Figueroa dispatched a half-dozen graduate students to community gardens across the city in 2019 to conduct interviews and collect data.

“Wherever there were raised planting beds, composting and trees, that significantly contributed to the garden’s capacity to absorb and retain water,” Mr. Figueroa said of the expedition’s findings.

City parks officials — who oversee the majority of community gardens through their GreenThumb program — acknowledge that the gardens are a vital part of New York’s green infrastructure. They “are a small, but mighty resource in our portfolio of storm water management efforts across the city,” said Jennifer Greenfeld, the deputy parks commissioner for environment and planning.

But not everyone agrees that community gardens should be labeled critical environmental areas. There is currently only one such designation in New York City, according to parks officials, and it is for an entire region: Jamaica Bay and it tributaries, tidal wetlands and adjacent areas. Community gardens are already protected from development under city rules, these officials argue, adding that not one garden in the GreenThumb program has closed in the past five years.

As more frequent and intense storms brought about by climate change are predicted to hit New York, much more needs to be done at all levels to “rainproof the city,” said Amy Chester, managing director of Rebuild by Design, a nonprofit that recently released a report on the importance of “transforming the concrete jungle into a sponge.” This can be as simple as putting out barrels in backyards to collect rainwater that can be reused for watering plants or washing cars to more ambitious projects like retrofitting school and office buildings with green roofs.

“We need to turn all of our surfaces in the public realm into spaces that absorb water,” Ms. Chester said. “There’s so much that we can do.”

In the Crown Heights neighborhood of Brooklyn, the Walt L. Shamel Community Garden collects rainwater from the roof of a nearby brownstone, which is piped into a 1,000-gallon tank. When the tank fills up, the overflow is sent to a bioswale with astilbe plants, violets and grasses.

“We’re paving over — and have paved over — so much of the city,” said Zachary Schulman, 41, a photographer and garden member. “This is a place where the water can go into the soil.”

Many gardens are the result of community organizing in the 1970s and 1980s, when residents banded together to salvage abandoned, rubble-strewn lots, like the site that became Pleasant Village in East Harlem, to make their neighborhoods better and grow food in tough times, Mr. Figueroa said.

This spirit continues today, with many gardeners fighting to overcome decades of pollution and adverse environmental effects from development, often in low-income neighborhoods where residents have limited access to parks. “Community gardeners do not accept environmental injustices and poverty as defining their destiny,” he said.

But Mr. Figueroa emphasized that those who are active in gardening — many of whom are growing food to save money so they can pay their rent — also want more affordable housing. There are creative ways to do both, he said, such as developments that have common areas with gardens or rooftops that can be used to grow fruits and vegetables.

It seems that some city officials are coming around to the need for balancing environmental concerns with housing needs. In the past eight years, 36 community gardens under the jurisdiction of the city’s housing agency have been transferred to the GreenThumb program, where they have more protection from development. Another 50 community gardens in subsidized housing complexes are also being added.

At the Mobilization for Change Community Garden, rainwater collected from the shed has been filling up watering cans for months. The rainwater harvesting system was installed by GrowNYC at a cost of $15,000, which was covered through a grant. Four barrels have also been set out to capture rainwater.

All this has made life easier for the gardeners, who used to have to run a hose across the street to tap into a fire hydrant at least a couple times a month. Now they only have to do that when they run low on rainwater.

“It’s convenience,” said Cara Sclafani, 46, a supply chain manager. “And it’s knowing that we’re making use of water that might otherwise be in the sewer.”