Some New Jersey towns are considering building seawalls as protection from future storms. There are some concerns, however, about the effectiveness of such a plan.
New Jersey Sierra Club director Jeff Tittel says a storm surge could go over or around a seawall and the waves that crash against it could lead to faster beach erosion.
But a structure to help protect the town might still be worthwhile, argues Belmar Mayor Matt Doherty.
“When a storm surge comes it does scour away the sand, but we’d prefer to lose sand than losing a boardwalk and the houses that were taken in Sandy,” he said Tuesday. “It’s one thing to replenish sand. It’s much more difficult to rebuild a boardwalk and to rebuild homes.”
Coastal research officials say, if constructed correctly, seawalls can help prevent damage to boardwalks and coastal communities. The construction costs can add up to millions of dollars to build them.
Stewart Farrell, director of the Coastal Research Center at Richard Stockton College, says building seawalls is definitely not worth the expense.
“If you’re going to deal with ocean waves, you need a double-sheeted wall with closely spaced pilings and several levels of whalers to tie it all together. You’re looking at substantial money,” he said.”Then you throw in concrete or rocks as a tow protection, you’re suddenly up in the $10,000-a-foot range.”
Seawalls act as the last line of defense to protect boardwalks and prevent coastal flooding during severe storms, says Jon Miller, a professor of coastal engineering as Stevens Institute of Technology.
“Even with these structures, there’s the potential that water may wash into the streets. We have to still be pretty vigilant about trying to make sure the construction on the landward side is elevated and is as secure and resistant as possible as well,” he suggested.