Raising houses in flood-prone areas has been a key part of rebuilding efforts following Hurricane Sandy. As the sea level continues to rise, however, experts warn there will come a time when, while the houses are safer from flooding, the roads and land around them could be inundated by twice-daily tides. Many of the lowest-lying communities along the South Jersey coast already see this when the moon is new or full. Examples include North Surrey and Harvard avenues in Ventnor Heights, or the bay side of Fifth Avenue in North Wildwood.

“I think you’re going to start seeing more of this (discussion) as people elevate their homes,” said Mark Mauriello, a coastal flood expert and former commissioner of the state Department of Environmental Protection. “The houses will be safe, but the roads are still going to flood. … If the streets are all underwater, then what is the point?”

Raising individual roads, or even just sections of roads, has been done for years, particularly along vulnerable highways that serve as evacuation routes. But neighborhood streets that see little traffic other than for residents have rarely been elevated, said Stew Farrell, director of the Coastal Research Center at Richard Stockton College.

“There haven’t been any discussions about total elevation because it’s really, really difficult, Farrell said. “If you jack the road up two feet, everyone’s lot is below the road grade, and when it rains, the water runs off into the lot.”

Raising entire sections of towns isn’t a new concept. Chicago did it in the late 1800s to solve its sewage problem. Galveston, Texas, did it after the 1900 hurricane that still ranks as America’s deadliest storm. The entire island was raised by 7 feet, and by 17 feet at the seawall, according to the city’s tourism and marketing bureau.

But all that was before sea-level rise was in the common language, particularly for barrier island communities. Various projections, including those by Rutgers University scientists and the National Oceanic and Atmospheric Administration, call for a rise in average sea level of about 1.2 feet by 2050 and more than 3 feet by 2100. Other projections say a rise of 6.6 feet is possible by 2100.

After Sandy was the first time homeowners anywhere in the nation were required to elevate their flood-damaged houses if a certain damage threshold was reached. Gov. Chris Christie issued an emergency order in January requiring homeowners elevate at least one foot above the most current base flood elevation maps, which indicate what the height of a 100-year or 1 percent flood would be.

Several weeks later, the federal government followed, setting the first unifying standard of building elevation following a flood in order for Sandy recovery projects to be paid for with federal dollars. The same standard now applies nationally as part of President Barack Obama’s climate-change initiative.

But these efforts focus either on elevating homes and buildings or rebuilding damaged infrastructure to higher, more storm-resilient heights.

“If you raise the houses, then you need to raise the streets,” said Martin Pagliughi, mayor of Avalon and Cape May County’s emergency management director.

The problem, Pagliughi said, is that trying to get all private-property owners — along with all municipal and utility entities involved — to raise the land on their property would never happen.

“I think it’s going to be entirely too cost-prohibitive,” Pagliughi said. “In Avalon, we’d have to raise 5,200 properties (the land, not the house) in conjunction with raising the roads and such. That would never happen.”

Elevating the streets comes with a host of other engineering issues and costs. Homeowners must elevate the land beneath their houses. Utility companies likely would need to raise water and sewer lines. Towns would need to elevate streets as well as revamp sidewalks, curbs and gutters.

That, in the end, is where the high costs come in, Mauriello said.

“Certainly if you throw enough money at the property, you can sustain the barrier islands in their location for a long time,” Mauriello said. “But as far as (elevating) all the land, you have to look at ultimately what the full costs are. You have to be honest about all of the costs over the period of time.”

In 1990, a Long Beach Island second-home owner and policy expert published a study examining the costs of several scenarios for how to save the buildings on a barrier island as the sea level rises certain amounts. Study author James Titus used Long Beach Island as a case study. The options? Doing nothing and letting nature take over when houses are damaged by storms; engineered retreat, or gradually filling in the back side of the island and moving houses back; elevating the island completely; or encircling the island with levees and dikes.

Each option came with several issues, with many homeowners facing costly decisions, according to the study. But complete elevation, Titus wrote, seemed to be the most pragmatic because homeowners would all get to stay in their elevated homes.

The cost to raise the land on the bay side of the island about three feet, without any of the additional infrastructure work, in 1990 dollars worked out to be more than $500 million. In today’s dollars, that amount would be nearly $1 billion for the fill material alone.

Today, Titus, a sea-level rise policy expert who has written multiple papers on the subject, said beach replenishment programs already are effectively elevating the ocean side of barrier islands. What’s left is to elevate the bay side of the island, and much of that work could be completed gradually as roads are resurfaced or utility lines upgraded, he said. The gradual elevation would likely be in line with the rate of sea-level rise, he said. “It’s a no-brainer. It’s silly not to (elevate the island).”

Towns and counties are going through dozens of projects that could be at least partially funded through the approximately $500 million hazard mitigation grant program dollars that have been released as part of the nearly $60 billion Sandy aid package approved by Congress in January.

In Cape May County, Pagliughi said, none of the projects submitted includes requests for large-scale road elevation.

“There were a couple small portions or on a dead-end stretch, but nothing on a big scale,” he said.

Highlands is the only town in New Jersey to consider a total elevation. The tiny borough nestled on the peninsula across the Shrewsbury River from Sea Bright in Monmouth County is uniquely positioned for the method to work, said Steven Szulecki, chairman of the borough’s environmental commission.

The borough is about three-quarters of a square mile in size, and a little less than half of the town is in the flood-prone downtown section, Szulecki said. More importantly, the other half of the town is on a steep hill, so any elevation would seem like a natural extension, Szulecki said.

Elevating the entire town about 10 feet is a logical fix to the current flooding problems, would help the town deal with a rising sea level and would provide significant flood protection for the next storm, Szulecki said.

Alternate solutions, he said, include building dunes or a berm around the city’s waterfront.

“If we do that, we are creating, if you will, a bathtub effect, and we would need to rely on pumps to pump out the water that collects during a rain event,” Szulecki said.

The total elevation concept was first proposed to the U.S. Army Corps of Engineers in 2001. In 2005, the agency determined the method not to be cost effective over a 50-year period, New York District spokesman Hector Mosley said. Initially any major flood-control projects to protect Highlands would have come with a 50 percent cost-share between the state and town. But after Sandy, the federal aid package approved by Congress has provided 100 percent funding, Mosley said. But because the project was deemed not cost-effective in 2005, Mosley said, that meant it was taken off the table.

The total elevation could cost several hundred million dollars. In addition to the sheer amount of dirt needed to fill the land up, all of the infrastructure, from roads to water and sewer pipes to gas and power lines, would need to be replaced and elevated, borough Administrator Tim Hill said. That is in addition to every property owner in the downtown elevating their buildings.

“If all of the pieces don’t work, then I don’t know how successful a partial project will be,” he said.

Contact Sarah Watson:


@acpresssarah on Twitter