A woman and child walk down a sidewalk in the Hurricane Sandy-devastated area of Breezy Point, Queens, July 3. Under a $19.5 billion blueprint released last month, New York outlined ambitious plans to fortify itself against storms and climate-related challenges. (Shannon Stapleton/Reuters)

Off a narrow road in a swampy part of Staten Island, Thomas Morello is preparing his two-family home for the next time the water pours in from Lower New York Bay, a quarter-mile or so away.

When Hurricane Sandy hit more than eight months ago, inundating but not destroying his converted summer cottage, Morel­lo discovered the house was not anchored to its foundation. Now, as he repairs the damage from water that rose almost to the second floor, he is bolting and screwing the structure to its pilings. He has elevated the electrical and heating systems. A previous owner had taken the most critical step, elevating the house about six feet.

Soon, the city will make similar preparations but on a vastly grander scale. Under a $19.5 billion blueprint released last month, New York outlined plans to fortify itself not only against the next big storm but against seas that scientists say could rise 21 / 2 feet by the 2050s and other climate-related challenges, including heat waves.

The 438-page plan, which involved a neighborhood-by-neighborhood survey of potential problems along 520 miles of coastline, vaults New York to the forefront of U.S. resilience planning, experts said, along with the gulf coast of Louisiana, which released its $50 billion plan in 2012.

“New York City’s sophistication in approaching climate adaptation is way at the top,” said Debra Knopman, vice president and director of the Rand Corp.’s justice, infrastructure and environment division, who has worked with Louisiana and is familiar with New York’s effort. “It’s a very, very impressive report.”

Still, many are waiting to see whether New York can and will follow through. That might depend on whether the next mayor is as committed to resilience planning as Mayor Michael R. Bloomberg (I) and whether the city can find the remaining $4.5 billion needed to carry out its plans. Officials here acknowledge that they will be returning to a deeply divided Congress for more money and to the Federal Emergency Management Agency for regulatory changes that will enable some of their efforts.

“The question is whether Sandy is enough of an impetus to maintain and sustain a plan like this,” said Jordan Fischbach, a policy researcher at Rand. “Is it close enough to the top of the list, and will it compete with other priorities in the decade or two to come?”

As Morello, a carpenter, and city officials here can attest, adapting to climate change is generally not technologically complex. It is mostly about raising homes, buildings and other vital facilities to escape rising seawater or, if that is impractical, building barriers . It is about taking advantage of the natural topography to help sap the strength of damaging storms, waterproofing and protecting critical infrastructure such as electrical grids and assessing the possible results of prolonged heat and drought, and trying to mitigate them.

“It’s not rocket science. A lot of these things are things we do already,” said Jessica Grannis, adaptation program manager at the Georgetown Climate Center at Georgetown University Law Center, a clearinghouse for information on such preparations. “It’s just tailoring them to a changed future.”

“It’s planning. It’s money. And it’s will,” said Daniel Zarrilli, New York’s director of resiliency, who lives on Staten Island, one of the areas hardest hit by Sandy.

Nineteen states and many localities, including Washington, are preparing such plans, according to Vicki Arroyo, the Georgetown center’s executive director. Chicago, which faces little flood danger, is figuring out how to cope with increasing heat. The five counties around low-lying Miami must determine how they can respond to rising waters. In Norfolk, there is talk of retreating from neighborhoods that flood regularly.

Still, the sheer scope of what New York hopes to protect is staggering. Under the FEMA maps last issued in 1983, 33 square miles of the city, or 11 percent of its land, were in danger of flooding in a 100-year storm — a storm that has a 1 percent chance of occurring in any year. Preliminary 2013 maps have increased that to 48 square miles. By the 2050s, 72 square miles, or 24 percent of the city, will face that danger because of sea-level rise.

About 398,000 homes will be in those flooding zones under the new FEMA maps. (The city has more waterfront than Miami, Boston, Los Angeles and San Francisco combined.) New York’s panel of climate experts predicts that the number of days each year when the temperature is above 90 degrees could triple to 52 by 2050.

The city supplies electricity to about 8.3 million people and 250,000 businesses; in the summer, its grid handles almost twice the load of the next largest city, Los Angeles. As Sandy showed, some critical power plants are in the flood plain, and distribution lines run underground. Both were disrupted.

Each day, 7.6 million people ride the city’s subways and buses, an additional 2 million cross bridges or come through tunnels, and 850,000 ride commuter rails. The city must provide food and water to similar numbers, and health care to tens of thousands. It supplies the 3.4 million gallons of gasoline and diesel fuel that vehicles burn every day.

The plan calls for an array of solutions. On Staten Island’s eastern shore, for example, the city wants to build levees and floodwalls, some 15to 20 feet high, that would protect, among other places, Morello’s Midland Beach neighborhood. On Newtown Creek, the Army Corps of Engineers would build surge barriers that would close during storms to keep water out of Long Island City. The hard-hit Rockaway Peninsula would get a dune system, including a double dune in Breezy Point, where 126 homes burned down during Sandy.

Coney Island’s beaches would be renourished, and breakers might be installed off the shores of Staten Island and the Bronx’s City Island to dampen waves. A wetlands restoration project in Queens is designed to do the same thing.

The most innovative project might be construction of a “Seaport City” atop a levee designed to protect the East River shoreline south of the Brooklyn Bridge. Modeled on Battery Park, the area would be home to residences and commercial development.

The city would offer $1.2 billion in loans or grants to help people retrofit homes against floods, mostly by elevating electrical, heating, air-conditioning and fire equipment and reinforcing walls.

And officials want FEMA to provide breaks on costly flood insurance for the 26,000 buildings in the new flood zone that cannot be elevated if owners take other measures, such as moving critical equipment higher.

One thing the city won’t do, said Seth W. Pinsky, president of the New York City Economic Development Corp., is retreat from the waterfront, where hugely expensive structures exist. With the exception of one neighborhood of 168 homes on Staten Island, there is no talk of buying out owners.

For Morello, who was trapped in his home with his wife and son during Sandy by water that rose to within two steps of the second floor, the choices are simpler. Standing in a yard adjacent to his house, not far from fields of eye-level weeds, he speaks of replacing joists, fortifying his house and “bringing it back to life” by the first anniversary of the storm.

Whether his plans or the city’s pan out depends on cost, priorities and the determination to see them through. But there is little disagreement among those who study climate change that they must.

“People realize this is the new normal and the next normal,” Georgetown’s Arroyo said. “It’s going to be a future that doesn’t look like the past, and it’s going to be a future that is dynamic.”