As the federal government considers a network of steel surge barriers to limit flooding in waters from Fire Island Inlet to the Throgs Neck Bridge, planners are working to reduce the chance that one region’s barrier could leave others in deeper water.
In the past four months, the U.S. Army Corps of Engineers, working with state and local governments, has prepared two preliminary studies contemplating an unprecedented series of measures that would prevent the surge-water impacts of the next superstorm Sandy, which caused $65 billion in damage in the metro region. The studies will inform a generation of projects throughout the region in coming decades, with the idea that the billions in infrastructure costs to fund the projects will far outweigh the costly impacts of flooding from future storms.
The projects range in cost from an estimated $36.4 billion for a 46-foot-high surge barrier spanning from Sandy Hook in New Jersey, to Breezy Point, Queens, to $85 million for the surge barrier proposed for the Gowanus Canal. Funding for the projects would be appropriated by Congress.
But even as the dozens of options ranging from unprecedented surge barriers and earthen levees are prepared for review by the public as soon as this month, officials say they have kept a careful eye on how these giant projects could interact with one another, perhaps shifting the burden of water from one area to another.
A 136-page New York Harbor and Tributary study by the Army Corps details a long list of surge barriers, levees, natural berms and other options, but waits until page 129 to state what could be the most problematic impact of the measures: “The closure of the barriers appears to enhance ocean storm surge for most of the simulated events ‘outside’ of the closed barrier.”
Federal officials say an aim of their exhaustive studies and complex computer modeling is to prevent that from happening.
“We’re going to look at the induced effects of our projects on other alternatives but also look at the effects of these projects on ours,” said Scott Sanderson, project manager of an Army Corps of Engineers report that’s examining ways to limit flooding in Nassau County bays. His group released its preliminary report April 30, with alternatives that range from barriers at Jones Inlet, Fire Island Inlet and East Rockaway Inlet. Also being studied are one or more north-south cross-bay barriers, including one along the Jones Beach Causeway at the end of Wantagh Parkway.
A public meeting about the preliminary study was held last week in Freeport.
A separate Army Corps division is eyeing potential storm surge from barriers to the west, but also is aware that closing any of its barriers, if approved, could alter conditions to the east or west. “The ultimate goal is not to move the problem elsewhere,” Sanderson said.
The initially proposed cross-bay surge barrier would extend north to south along the southern end of the Wantagh Parkway, all the way to Jones Beach, and limit surge-water impacts on coastal communities on either side of the barrier — depending on which direction is sending the tidal surge. “The cross-bay barrier connecting Jones Island to the mainland would prevent water within the Great South Bay from inundating the western shore of the back bay area,” the study says.
Planners say they know there could be winners and losers in such a scenario. Other cross-bay barriers are being studied at the Robert Moses Causeway and Meadowbrook Parkway, Sanderson said.
“With north-south barriers going across the bay and winds being east to west, the downwind side is obviously the beneficiary, while the upwind side experiences higher water levels,” said Jeff Gebert, an oceanographer for the Army Corps. “There’s the potential for adverse effects” for the latter.
At the Freeport public meeting, officials said they’ve been running computer models of the impact of the inlet barriers alone, and found the protection was not as significant as expected. But a greater benefit was modeled with inlet surge barriers and a cross-bay barrier, the agency said. They plan to run additional computer models to fully test the options, Sanderson said.
The environmental impacts from barriers could be “significant,” he said.
“There’s environmental impacts we’re going to have to consider both direct and indirect related to construction of these barriers,” he said. “There’s going to be impacts on hydraulics in the bay — just the structure itself is going to inhibit the flow that exists, probably even when it’s opened.”
Local officials anxious about a repeat of superstorm Sandy are equally concerned about winners and losers in the surge barrier planning.
“Every time you erect a barrier there’s someone on one side and someone on the other side. It’s going to be controversial,” said State Sen. Todd Kaminsky (D-Long Beach), whose community was hard hit by Sandy. It’s going to take a lot of careful study, public input, and careful review by public officials to make sure no community comes out worse as a result, he said. “Long Island representatives certainly won’t let that happen,” Kaminsky said.
Some are questioning whether barriers that have worked well elsewhere, including one in New Bedford Harbor in Massachusetts since the 1960s, will do as well for Long Island, where shifting sands are the norm.
“Every time man has put something permanent against the ocean it’s failed,” said Gil Hanse, emergency manager for the Town of Babylon, who attended an Army Corps meeting in Freeport last week. “Where you harden, updrift or downdrift, you’re going to cause a problem.”
“We’re sand, we were made by the glaciers and we were designed to move,” Hanse said of Long Island and it’s South Shore beaches. “The inlets themselves, they want to move.”
Daniel Zarrilli, chief resilience officer for New York City, estimated that flooding in Nassau and some areas of New Jersey could be about a foot higher if the Army Corps moves ahead with the Sandy Hook-Rockaways barrier. Such a plan also envisions a surge barrier at Throgs Neck to prevent inundation into New York City from the north.
A separate Army Corps study that examined options to protect the area from Fire Island to Montauk Point proposed no steer barriers at the inlets, but instead pondered raised roadways, earthen levees and other natural fixes. One expert who is following developments closely said there’s a reason lots of study is important before moving forward.
“If you’re stopping the water from going someplace it’s got to go somewhere else,” said Aram Terchunian, a coastal geologist and president of First Coastal Consulting Corp., in Westhampton Beach. “The question is how much and where? Until they do some real hard modeling they’re not going to know the answers.
One South Shore elected official sees the solution as a simple one — erect surge barriers at Reynolds Channel, Jones Beach Inlet and Fire Island Inlet, and close them in the hours before a big storm’s about to hit, said Robert T. Kennedy, mayor of the Village of Freeport, which saw severe flooding during Sandy.
He grows impatient when talking about the long timeline of the costly studies being planned, and points to successful surge barriers in Stamford, Connecticut, and New Bedford, as examples of what Long Island needs to do — now. “So, are you going to start working on the gates, next week?” Kennedy asked Army Corps managers at last week’s public meeting, knowing that years of study will precede any final construction, which in some cases is a decade away.
Long Islanders who experienced the worst of superstorm Sandy say they are just as anxious to see the problem solved. Marian Goldstein of Baldwin Harbor was home that October night when a wall of water filled her house at ground level and began encroaching up the stairs. She went to bed that night thinking she wouldn’t survive the night. Power was out for more than two weeks, and it took months to rebuild and refurnish. “My feeling was the house was going to collapse,” she said. Surge barriers in her water-surrounded community “are the only way this area’s going to be saved,” said Goldstein.
But some say beyond protecting homes and businesses, the studies need to do more to identify and fortify critical infrastructure.
Sarah Meyland, associate professor at the New York Institute of Technology’s School of Engineering, and director of the Center for Water Resources Management at NYIT, said even as planners consider big-picture projects to protect homes and businesses from storm surge, specific plans to protect infrastructure, including sewage treatment plants on the South Shore, require special attention.
“Aside from being vulnerable to surges, these plants are just plain vulnerable to sea-level rise, which by all accounts is going to go up in our lifetime,” Meyland said. “It may be a good thing to start now to identify the most crucial bits of infrastructure that are so important to the counties and start looking at how we can back those up. I don’t think building a big wall around them is going to be successful long term.”
Army Corps officials said once surge barriers are built, operations and maintenance of the devices could be turned over to the “nonfederal sponsor” for local control. At their June meeting, officials were asked if that could lead to different municipalities with differing priorities opening or closing the barriers at cross purposes. Sanderson said it couldn’t happen.
“When a federal project is recommended and implemented, there’s a certain operation and maintenance plan associated with that. Operation and maintenance has to follow that plan. It can’t be augmented or used in different ways. It has to follow the operation and maintenance plan.”