New Jersey shore
Sea-level rise threatens bay shores, wetlands
Posted by the Asbury Park Press on 02/5/07
BY TODD B. BATES
AND KIRK MOORE
A rising sea level. Greater coastal flooding. Threats to wetlands.
New Jersey's future will include these and other key issues, according to experts interviewed before and after a new international report on climate change was released on Friday.
"Basically . . . the future doesn't look good" because the coast is being submerged by rising water and eroded because no new sediment is coming in, said Norbert P. Psuty, a coastal expert at Rutgers University's Institute of Marine and Coastal Sciences.
"We're . . . in a very pre-carious situation" in many parts of the coast, said Psuty, director of Sandy Hook Cooperative Research Programs.
But people can adjust by elevating their homes, yards and streets and by replenishing beaches, including those on the bay side, said James G. Titus, project manager for sea-level rise at the U.S. Environmental Protection Agency since 1982.
"People can adapt" to a rising sea level, said Titus, who has vacationed on vulnerable Long Beach Island since 1955. "People can plan for it."
The new Intergovernmental Panel on Climate Change summary report â€” "Climate Change 2007: The Physical Science Basis" â€” prompted a mixture of pessimism, pragmatism and optimism last week.
The global sea level may increase by anywhere from 7 to 23 inches by 2090 to 2099, compared with the 1980 to 1999 period, according to projections in the report. Those projections do not account for the possibility of rapid changes in ice flow from Greenland and Antarctica.
Some officials in New Jersey have been planning for sea level rise and the threat of storms riding on higher water levels.
"It's the frequency of storms that . . . we're going to have to worry about in the future," said Kenneth E. Pringle, Belmar mayor.
"With the sea level rising, it just becomes much more difficult to protect (the) community against the increased number of natural events that can cause property damage," Pringle said.
Belmar officials have been working on protection efforts and emergency response plans, he said.
New Jersey's relative sea level rose about 16 inches in the last century and is increasing at a rate that's about twice the global average, Psuty said. About half of New Jersey's increase is due to the land sinking.
"My analysis of the data suggests that there is actually an increasing rate of sea-level rise in the last few decades," and that would result in a water level about 24 or 25 inches higher in the next century, he said.
Titus said the sea might rise three feet off New Jersey this century.
Meanwhile, Long Beach Township has not yet made any plans to deal with sea-level rise, although the proposed beach restoration project on Long Beach Island would provide protection, said Robert A. Palmer, a Long Beach Township commissioner.
"We have to be careful what legacy we leave . . . to our future generations," Palmer said.
"Maybe it's about time (to) start looking at this a little more seriously," he said.
Mark Mauriello, assistant commissioner for land use management in the Department of Environmental Protection, said the state has taken numerous steps to deal with sea-level rise.
They include proposing new rules for flood hazard areas, and beginning to consider the long-term trend of sea-level rise as it relates to development proposals and wetlands mitigation, Mauriello said.
Another effort is trying to get municipalities to plan for "multiple hazards," including flooding and erosion, both of which are affected by potential sea level rise, he said.
More frequent floods
New Jersey's coastal areas have "very, very low" elevations, especially on the bay sides of barrier islands and the mainland sides of bays, where much of the lagoon housing is located, according to Psuty.
A higher sea level will "produce a lot of localized flooding," he said.
Any storms will cause even more flooding, with storm surges on top of the higher sea level, Psuty said.
The kind of flooding generated by the December 1992 and March 1962 nor'easters would happen more often during less severe storms, he said.
Some places along the margins of Barnegat Bay already have water "lapping onto the streets" during a spring tide â€” without any storm, he said.
A spring tide, which is higher than a normal tide, occurs around the time of the new and full moons, according to a National Weather Service Web site.
Sea-level rise will "mean that storms will reach higher inland and higher upon the dunes," said Stewart C. Farrell, director of the Coastal Research Center at Richard Stockton College of New Jersey.
The challenge for virtually all of New Jersey's coastal communities is to "sort of anticipate" the effects of increasing sea level rise and "increased storm effects and begin to think in terms of being able to move people and things out of these hazardous areas," Psuty said.
Storms could result in "some major destruction, and then the question would be whether or not" you want to go back into the area, he said.
The most immediate and momentous effect of sea level rise won't be on beachfront communities, but the low-lying salt marshes on the fringe of New Jersey's bay shores, predicts Michael J. Kennish, a research professor at the Rutgers marine institute.
Bay shores at risk
Beach replenishment projects will hold the public's attention for a while. But in the meantime, sea level will make an end run around barrier beaches and islands, raising tides and long-term erosion trends along fragile shores of mud and grass, Kennish said recently.
Eventually bay-shore erosion will be as much of a threat as receding beaches, as bay water approaches mainland roads, utility lines and other infrastructure, he said.
"If we continue to develop our bay shorelines with bulkheading and in-filling . . . we're going to end up with . . . a big bathtub and no marshes because they'll drown," said Thomas O. Herrington, associate professor of ocean engineering at Stevens Institute of Technology in Hoboken.
This summer, researchers on Delaware Bay will experiment with an alternative to bulkheads and revetments: "living bulkheads" of oysters and mussels, planted to stabilize bay shores.
"New problems give you an opportunity to give you new solutions," Titus said.
Having a nice beach and marshes on the bay side "instead of just the bulkhead, you could just end up better," he said.