When Hurricane Sandy made landfall in New Jersey in 2012, it washed away miles of beaches that the government paid billions to restore afterward. Few preventative countermeasures were in place. Now, as the Mid-Atlantic waits to see if it’s in Hurricane Joaquin’s path, whether or not its coastal communities are ready for a major storm might be put to the test.
Many places along the East Coast, like Norfolk, Virginia and Charleston, South Carolina, know they’re at risk for storm surge flooding. A storm surge is an increase in water level caused by the strong winds the storm creates. Unfortunately, the only completely effective way to reduce this risk is both unpopular and impractical.
“The only thing that can be done to alleviate it is to get the most important infrastructure out of places that are likely to flood,” says Robert Young, the director of the Program for the Study of Developed Coastlines and a professor of geology at Western Carolina University. Leaving established communities isn’t seen as viable according to Young, so coastal ones tend “to do things to try to block the storm surge like spending money to build beaches and dunes or elevate property above the [projected] storm surge levels or surge heights.”
Beaches and dunes help bear the brunt of storm-related flooding, which is one of the reasons they’re restored after devastating storms despite the multi-billion dollar price tag. “If you’re lucky, and the beaches and dunes you’ve built are high enough and wide enough, they can block the elevated water level from getting into your community,” Young says.
There are two problems with this method of protection, according to Young. Beaches and dunes only provide protection for typically fast-moving and weak storms. If a storm is particularly intense or long lasting it can breach these defenses. Also, no matter how well built the beaches and dunes might be, they’re a temporary solution because they will still erode. “Over the long term, you’ll have to do it all over again,” Young says.
Newly restored beaches can be a financial gamble as well. A strong storm could occur shortly after restoration and destroy the shoreline all over again. That’s a concern for Joaquin. “Depending on the track,” Young says, Joaquin “could tear up a lot of the beaches that the Army Core of Engineers just spent billions of dollars rebuilding along the shore of New Jersey and New York.”
Unlike beachfront houses, buildings in cities can’t simply be raised above predicted storm surge levels. They can be remodeled so lower floors do not house people or critical equipment, but that can be expensive. Other infrastructure, such as subways, is far more difficult to protect. During Hurricane Sandy the surge caused extensive damage as it flooded subway tunnels and city streets. Unfortunately, flooding due to storms in New York City is likely to become more common due to sea level rise, according to a paper published in PNAS on September 29.
Relocating cities at risk of flooding, like Norfolk, Virginia and Charleston, South Carolina, is not an option. The residents of these cities know they’re vulnerable to storms, however, so they focus on seriously preparing for evacuation, following established hurricane evacuation routes.
City officials can also consider more long-term preventative measures. “They’re just trying to figure out how to pay for it,” Young says. Options include erecting seawalls and levees, which serve to hold back the surge.
Currently, there’s no national plan in place to determine how money is spent to rebuild after storms. Rebuilding efforts cost billions of dollars, often in places that might not justify the expense. Young isn’t convinced that the cost of rebuilding beachfront vacation communities in places like the Jersey Shore, for example, was one the federal government needed to bear. Instead, he believes the community itself should be responsible for rebuilding, as they chose to develop areas known to be at risk for flooding and storm-related destruction.
Despite efforts to maintain it, the coastline is naturally constantly changing. Hurricanes and coastal storms are the main cause of beach erosion and shoreline change. Powerful ones could create entirely new inlets or split a barrier island in half, and little can be done to prevent that.
“Ultimately, we can’t protect everybody, everywhere,” Young warns. Determining what places most require federal aid, both for rebuilding and protective measures, is a necessary next step for how we handle hurricanes.