Protecting Barnegat Bay from floods: Are gates at the inlets the answer?

Asbury Park Press (NJ)

Could blocking three inlets protect thousands of Jersey Shore homes threatened by flooding from future storms? How about lifting 18,800 structures to move them out of harm's way?

A new 561-page report by the U.S. Army Corps of Engineers, prepared for the New Jersey Department of Environmental Protection, suggests massive construction projects may be needed to protect flood-prone areas of the Jersey Shore and its tourist-reliant economy.

The report recommends some $16 billion worth of construction projects between Long Branch and Cape May in order to protect New Jersey's "back bays." These low-lying areas around bays, rivers and coastal lakes are susceptible to storm and high-tide flooding.

"What the study identifies... are a combination of storm-surge barriers across multiple inlets, cross-bay barriers, and as many as 18,000 building elevations in vulnerable communities along those coastal areas," Department of Environmental Protection Commission Shawn LaTourette said in a virtual news conference Wednesday ahead of the release of the report.

Flood gates would keep out storm surges by closing the Manasquan, Barnegat and Great Egg Harbor inlets. The three flood barriers would help to stop water from the Atlantic Ocean from inundating the Barnegat, Manahawkin, Little Egg Harbor and Great bays during coastal storms, according to the report.

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The gates would only be closed for storms and large flood events, U.S. Army Corps of Engineers officials said during the news conference.

Already, the Department of Environmental Protection has launched other flood resiliency projects, such as expanding wetlands and building oyster reefs, to help absorb storm water and reduce wave velocity from storms, in these regions.

Expanding those projects will likely be included in future flood mitigation efforts, according to the Army Corps report.

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The Army Corps' proposals are dependent on Congressional approval as well as the availability of state and local funding.

But doing nothing could incur even higher costs, LaTourette said.

Since the establishment of the National Flood Insurance Program in 1978, more than $5.3 billion in flood claims have been paid to New Jersey residents, according to the Army Corps' report. Of that, $2.9 billion was paid for flood damage in coastal counties: Monmouth, Ocean, Atlantic and Cape May County.

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On average, flooding accounts for about $1.2 billion in damage annually in New Jersey, said Peter Blum, planning chief at the Philadelphia division of the Army Corps of Engineers.

The proposed projects, if approved, would diminish the risk from future flooding, but do not eliminate that risk completely, LaTourette said.

"We're not going to be able to stop all damages," Blum said. "There's still going to be things that get damaged with projects in place."

However, "there is a clear cost benefit to protect (the coastal regions of New Jersey) through the suite of measures that are put forward in this draft feasibility study," said LaTourette. "Otherwise (the region) would continue to suffer those damages and perhaps worse."

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Scientists say there is a 50% chance that sea level around New Jersey will rise 1.4 feet by 2050.

The Army Corps will hold a virtual public meeting to discuss the report and answer questions from 6 to 7:30 p.m. Sept. 20 and from 1 to 2:30 p.m. Sept. 21. Webinar instructions are available online at https://www.nap.usace.army.mil/Missions/Civil-Works/New-Jersey-Back-Bays-Study/. Questions will be accepted by email at PDPA-NAP@usace.army.mil.

Amanda Oglesby is an Ocean County native who covers Brick, Barnegat and Lacey townships as well as the environment. She has worked for the Press for more than a decade. Reach her at @OglesbyAPP, aoglesby@gannettnj.com or 732-557-5701.