SEA ISLE CITY — Cape May County is preparing to go out to bid this year on an ambitious project to rebuild Sea Isle’s causeway.
The $9 million project will raise the 2-mile-long road with nearly 5 feet of sand and dredge spoils to ensure it is passable during coastal storms and back-bay flooding, which is expected to grow worse with rising sea levels.
The project is one of the first examples of Cape May County responding to the effects of global warming, officials said.
“The issue here is sea levels are rising,” Cape May County Engineer Dale Foster said. “And we’re seeing a good majority of high tides pushing the limits. It’s a long-term thing to look at.”
The project is one of six flood-prone causeways the county would like to address in coming years. Others, including Ocean City’s nearly completed Route 52 and North Wildwood’s causeway, were built above the 100-year flood stage, which means the roads would accommodate the worst flooding seen in the past 100 years.
“We’d like to be able to do every one of our causeways, but it’s so expensive and takes a long time,” Foster said.
Sea Isle City is hardly alone in contending with the coastal flooding, Mayor and Cape May County Freeholder Leonard Desiderio said.
“This is not just a Sea Isle City problem. It’s throughout the county. Coastal communities will have to find ways to get the water out quickly,” he said. “Some may include raising roads like the county is doing.”
Climate change is likely to spur similar expensive solutions in South Jersey, said Doug O’Malley, director of the nonprofit group Environment New Jersey.
“This is the first sign that Cape May County is in a terrible fix,” he said. “Looking at the science on climate change, a majority of our shore towns will face not only sea-level rise but also increasing storm surge in coming decades.”
Simply building higher is not the solution, he said.
“The scary thing is we can’t engineer our way out of this crisis,” he said. “We need to solve the root of the problem with global-warming emissions.”
During big storms, the marshes along Cape May County’s coastline become vast inland seas that illustrate how Sea Isle City is indeed an island. The causeways become narrow ribbons of land connecting them to the mainland.
“The Sea Isle causeway is probably closer to the marsh level than any surrounding causeways,” said Roger Wood, director of research for the Wetlands Institute.
This tourist attraction and research institute sits on another nearby causeway, Stone Harbor Boulevard.
“That’s one of the beneficial functions of a salt marsh. If there’s a big storm, the marshes act as a buffer between the ocean and the mainland,” Wood said. “They can store up a lot of incoming water.”
Wood said rising sea levels are likely contributing to coastal flooding that is wreaking havoc this year on nesting birds in places such as Stone Harbor Point.
“We have a group of students monitoring beach-nesting birds. Those birds have had a tough year because these nesting beaches have been washed out by storms,” Wood said.
The flooding creates similar hazards for people. Sea Isle City’s main entrance, JFK Boulevard, is especially prone to severe flooding. One goal of the project is improve drainage here to ensure that residents can evacuate safely during a storm.
The county plans to raise JFK Boulevard by about 16 inches, which alone will not be enough to keep drivers out of harm’s way, Foster said.
“Unfortunately we can’t raise it to 4½ feet like Sea Isle Boulevard,” he said.
The solution will be installing better drainage systems and designing the road to shed rainwater quickly.
“We have tidal flooding at abnormal high tides and stormwater-runoff flooding,” Foster said.
The Sea Isle City work is expected to take about three years. The duration is necessary to ensure the new road bed settles properly. Drivers on the causeway now can see the effects of improper settling on the jouncy and uneven road.
Two lanes of traffic will be open throughout the construction.
“Three years will go very quickly. The quicker the county can get out the bids and get started, obviously the faster it will be over,” Desiderio said. “We’ll make it as painless as possible.”
The state Department of Environmental Protection is reviewing the county’s permit application now. The project is designed to disturb as little wetlands as possible, Foster said. The county is investigating whether it can use old dredge spoils as fill, which would free up a spoils site for future use by Avalon.
And the project is turtle-friendly. It will feature extra-wide culverts for safe crossings by diamondback terrapins and permanent fences to keep them off the busy road.
The county plans to go out to bid later this year.
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