Though they live just a half-mile from the Paerdegat Basin in Brooklyn, George and Laura Fishman were spared the kind of damage that upended their neighbors’ lives during Hurricane Sandy. (There were not, for instance, fish in their basement.)
But that posed a problem of its own.
How, the Fishmans asked themselves, can we prepare for the next one? Should we buy flood insurance? Should we elevate our boiler and water heater? Should we get out altogether?
These are not isolated concerns. Communities across the country are confronting the mounting evidence of climate change, even as the Trump administration has rolled back environmental laws and regulations and dismissed members of an important science panel.
The New York Times is presenting case studies, and an associated glossary, examining tangible measures in and around New York City to make buildings and infrastructure more resilient in the face of floods, surges, high winds and heavy rains.
That effort reaches all the way to a two-story semidetached brick-and-frame house on Avenue M in the Canarsie neighborhood that the Fishmans have owned for 42 years. Canarsie sits on the vast Jamaica Bay. Numerous creeks and basins, like the Paerdegat, penetrate upland from the bay, putting surrounding areas at risk of flooding.
Dr. Fishman, 66, is a professor emerita of history at York College in Jamaica, Queens. Mr. Fishman, 68, is a retired middle school teacher and administrator in Brooklyn and Queens. He loves stained glass. Panels with ruby roses and cardinals alternate in windows around the house with panels showing a striped lighthouse and a striped clown fish.
“We settled here because it was very convenient to our jobs, it was close to where our parents lived, it was less congested and it was close to the water,” Dr. Fishman said. “And George is a kayaker.”
On existing flood maps, the Fishmans’ property is not in a high-risk zone. They did not have to obtain expensive flood insurance to qualify for a mortgage, which they have since paid off.
During Hurricane Sandy in 2012, their house emerged unscathed while basements in surrounding houses were flooded by the Paerdegat Basin. Cars and trees around them were lost to saltwater. Power was out for 48 hours. And the sewer backed up. But the pitch of the Fishmans’ street ensured that the floodwaters only lapped up near their yard.
They cannot, however, keep counting on good luck. Through Neighborhood Housing Services of Brooklyn, a nonprofit, they learned that they qualified for a free home audit, conducted by an engineering firm and a surveying firm, and a free elevation certificate, which is necessary to get an accurate flood insurance quote.
The audit program is run by the nonprofit Center for NYC Neighborhoods. The center maintains a website, FloodHelpNY.org, where city residents can check to see whether they are in a flood zone and eligible for a free audit and certificate, which might otherwise cost $1,800.
Christie Peale, the executive director of the center, said, “There is only so much information you can give people from publicly available data.
“People have to understand the technical specifics of their property in relation to the flood plain,” Ms. Peale said. “Are you above it? Do you have livable spaces below it? Where is the lowest part of your property that intersects with the flood plain? We really don’t want folks to put their heads in the sand and pretend this isn’t an issue.”
Financing for the $7.5 million audit program comes through the Governor’s Office of Storm Recovery. Gov. Andrew M. Cuomo wanted to “give storm-impacted communities, like Canarsie, the opportunity to program federal recovery dollars to meet their unique needs,” Catie Marshall, a spokeswoman for the office, said.
The program is “now serving hundreds of homeowners like the Fishmans,” she added.
Mr. Davidson used a Ziplevel altimeter to determine the elevation, in relation to mean sea level, of various parts of the house — most critically the basement floor.
The altimeter has a hand-held measurement module tethered by a 100-foot cord to a small base unit. Mr. Davidson entered a reference elevation on the module (in this case, mean sea level) and then took readings by moving the module from one spot to the next.
“The changes in vertical pressure of a liquid sealed in the pressurized cord indicates to the module where it is in vertical relation to a preset reference level,” said Dennis Vories, the electrical engineer who invented and designed the device.
For example, when Mr. Davidson placed the module on the basement floor, the display read “06.03 FT,” meaning that it was 6.03 feet above mean sea level.
Mean sea level differs from the National Geodetic Vertical Datum, the benchmark that the Federal Emergency Management Agency used on the current, interim flood insurance map. Back at the office, Mr. Davidson ran the data he had collected through custom software. It made a technical correction that yielded a certified elevation of 7.1 feet.
That happens to be around three feet below the base flood elevation for the area, meaning that the Fishmans’ basement could be under three feet of water during a 100-year flood.
On the interim map, however, the Fishmans’ house is not within the high-risk 100-year flood plain. But the city expects to complete new insurance maps in three to five years, working with FEMA. Conceivably, the boundaries of the 100-year flood plain could be redrawn to include the Fishmans’ house. If so, it would formally be regarded as high risk.
The preceding paragraphs only hint at the nearly impenetrable complexity of flood risk assessment. It’s easy to see why homeowners need all the technical help they can get.
On May 1, the Fishmans sat down with Elizabeth Malone and Nadine Carpenter of Neighborhood Housing Services, who helped them interpret the elevation certificate.
“It was recommended that we seal the basement floor,” Dr. Fishman said. “We are seriously considering this. But we are not going to raise our ‘mechanicals’ by moving them to the first floor. The engineer’s report indicated that this would cost between $10,000 and $15,000.”
“Because of our location and the fact that we do not have a mortgage, we are not required to purchase flood insurance,” she said in an email. “But it might be a good idea since now we qualify for a ‘preferred rate’ policy. The premiums are relatively low, and if we sell our home, this lower base rate will be transferred to the new owner.”
Sell their home? Where would they rather be than in Canarsie?
“We wanted to live near the water because it’s so beautiful,” Dr. Fishman said. “It’s a double-edged sword.”