12 years after Superstorm Sandy, Long Island remains vulnerable, experts say

A dozen years ago, Superstorm Sandy charged onto Long Island’s coastline, resulting in an estimated $65 billion in damage to South Shore communities, destroying 100,000 homes and causing the deaths of 13 people. The storm surge reached more than 12 feet in some places, and waves of up to 17 feet thrashed the shoreline.

Ever since, government officials and environmentalists throughout the Northeast — much of which was ravaged by Sandy — have been studying and debating how best to protect the region from future storms. While there have been some improvements in bolstering Long Island's shoreline, no major islandwide solution has been found to protect Long Island from the next Sandy.

While the U.S. Army Corps of Engineers is continuing multiple studies of how to strengthen the region, Long Island officials and advocates remain divided on the best strategies. And meanwhile, rising sea levels and warming oceans are producing increasingly powerful storms that will one day aim for Long Island, experts said. 

"I’m sad to say we’re not any more ready than during Sandy," said Adrienne Esposito, executive director of Citizens Campaign for the Environment, a Long Island nonprofit environmental group. "We have done a lot of assessments on how we can be safer, but now we need more implementation. We need to move the infrastructure up to higher ground or move it back from the shoreline. We know what we need to do, it’s just expensive and it’s difficult."

Choosing the best storm protection

The Army Corps of Engineers, in an ongoing study that produced preliminary models in 2021 looking at Nassau's Back Bays, warned that "with no federal project in place," the region could face $1 billion in average annual flood damages from 2030 to 2080 as a result of coastal storms, relative sea-level change, erosion and inundation.

The study should be completed next spring but is awaiting more federal funding.

Some of the most examined recommendations by local and federal officials have included raising buildings, restoring or building up natural wetlands to protect the shoreline and potentially adding storm surge barriers at inlets to protect Nassau County’s South Shore.

Protections completed since Sandy have included a $130 million dune and jetty project built in Long Beach and $1.5 billion in ongoing dune work and beach protections to combat erosion along 83 miles of coastline from Fire Island to Montauk Point.

Sen. Chuck Schumer (D-N.Y.) advocated for the 2012, $60 billion Sandy relief project following the storm, which included the dune projects, additional funding to help homeowners and to restore the Bay Park sewage treatment plant.

Schumer, now Senate majority leader, told Newsday: "These storms are never easy to predict, but we’re in a lot better shape than we were. We need greater resiliency. Our homes and roads and public entities by the water need to be rebuilt with resiliency in mind."

The preliminary draft of the Army Corps study initially called for raising 14,000 homes on Long Island, at a cost of $3 billion. But that figure was reduced to 6,000 homes due to the expense. The report also recommended floodproofing 2,300 businesses and industrial buildings by elevating buildings up to 3 feet while also floodproofing walls, doors and windows.

The study looked at permanent structures to protect critical infrastructure. The City of Long Beach is using $33.5 million in federal funding to build 2,500 linear feet of steel bulkheading around the city’s electric grid and water treatment center.

Barriers to keep out the surge

The Army Corps is also studying storm surge barriers, which are a series of movable gates in the water that close during a high surge. But while keeping the option open, two different studies by the agency concluded they weren't a good fit for Long Island.

The Back Bay study found storm surge barriers would likely reduce flooding in protected areas by 1 to 2 feet, but storm surge outside the tidal gates could cause additional flooding by raising water elevations by 2 to 4 feet, especially in communities along Great South Bay, according to the Army Corps study.

Freeport Mayor Robert Kennedy has urged the Army Corps to consider adding such barriers at Jones and Rockaway inlets, which he said would be able to close off Reynolds Channel and the Western Bays during a major storm.

He said nearly 4,000 homes in Freeport were under up to 6 feet of saltwater during Sandy. Of homes in the flood district, only 330 have been raised and the Army Corps proposal would address fewer than 10% of 118,000 waterfront homes on Long Island, Kennedy said.

"You can protect the entire South Shore of Long Island," Kennedy said. "I know it will be an effective method of protecting everybody on Long Island."

But Corps officials told Kennedy that, beyond the prohibitive cost and practicality of building such barriers, yet another obstacle is that the entire Long Island coast is in a CBRA zone, or Coastal Barrier Resources System, which restricts federal funding and development. The zone, however, has exceptions for development for health and safety, Kennedy argued.

A separate study by the Army Corps of the New York City and New Jersey shoreline looked at different combinations of storm surge barriers and tentatively selected one with some sea gates and some land-based barriers at the entrance to Jamaica Bay and the Rockaway Peninsula, as well as several on the New Jersey side of New York Harbor, lower Manhattan and East Harlem. The proposed plan would also include floodwalls and levees as well as nature-based solutions such as wetlands.

The Army Corps estimated the total cost at about $52.6 billion, but the benefits are estimated at 2.5 times as much in terms of protecting the coastline.

Malcolm Bowman, a professor with Stony Brook University's School of Marine and Atmospheric Sciences, prepared a study on storm barriers for the state Department of Environmental Conservation. He said adding storm surge barriers would be feasible, but would need to protect the entire coastline of Long Island’s South Shore.

"It would be possible to have these gates normally open and allow the water in and out and closed for a few hours during a strong storm surge and giant waves," Bowman said. "It’s expensive, but what is the risk of not doing anything?"

But another expert, Phil Orton, research associate professor of ocean engineering at Stevens Institute of Technology, said there can be unintended side effects by adding storm barriers.

If coastal wetlands don’t naturally flood, they are deprived of the sediment they need to stay healthy, Orton said.

"You’re changing the way our coasts work and our estuaries work. They can curtail animal migration, curtail connectivity, they can change sedimentary systems and the marshes," Orton said. "Having those barriers, there will be demand to use them. Those negative effects go up with the frequency of closures.”