This article was originally published by Yale Environment 360. Read the original story here.

Rounding the corner near the village of Rodanthe, there is a stretch of highway known as the S-Curves because of its twisting loops and turns. It is, by almost any measure, one of the most vulnerable sections of roadway in North Carolina, if not the nation. Years ago, highway officials erected a massive dike here with 2,200 sandbags—each bag was 15 feet long, two feet tall, and five feet wide—and then buried the dike in even more sand in an effort to keep the ocean at bay and the highway, known as NC 12, open.

It didn’t work, or at least it didn’t work as hoped. The Atlantic Ocean continued to pummel the towering artificial dune, crashing over the top, tearing apart sandbags, and flooding the highway — closing the only access on and off of the lower Outer Banks for days and sometimes weeks.

Following each storm, the North Carolina Department of Transportation (DOT) sent in bulldozers and graders to rebuild the sand dike and patch the road, only to watch the next storm undo its work. “It’s like the Siege of Troy,” said local biologist Mike Bryant. “It just goes on and on.”

Bryant managed the nearby Pea Island National Wildlife Refuge—a sprawling, 13-mile-long sanctuary that attracts tundra swans, Canadian geese and 400 other species of migrating birds for two decades. He estimated that he spent 60 percent of his time on NC 12, including issuing permits to state and federal engineers to repair storm damage and severely eroding sand dunes. “It felt exhausting at times,” he said.

In one sense, NC 12 stands as a metaphor for the dangers of building anything on a highly dynamic, constantly-shifting barrier island, especially one that has lost hundreds of feet of shoreline in places over the last century and now faces even-larger threats from sea level rise and more frequent and powerful storms related to climate change. The risks aren’t limited to the Outer Banks, of course. Nationally, U.S. coastal resorts from Cape Cod to Miami to Galveston face unprecedented and costly challenges as their shorelines narrow and floodwaters inch ever-closer to millions of houses, condominiums and hotels—over $1 trillion worth of property in all.

Still, nowhere are the threats more visible than along the famed Outer Banks of North Carolina, where each summer a flotilla of SUVs deliver eager vacationers, swelling the population nearly tenfold, to over 300,000, while also fueling a tourist economy that supports thousands of jobs and generates millions in tax revenues for local governments.

Nearly four decades ago, the University of Virginia coastal geologist Robert Dolan, a long-time researcher of barrier islands, wrote that the Outer Banks are “one of the highest natural-hazard risk zones along the entire Eastern Seaboard of the United States.” He cited the Banks’ unique geography and risky exposure to storms, volatile currents and percussive winds.

Viewed from an airplane, the nearly 200-mile-long ribbon of islands resembles a child’s Etch-A-Sketch drawing, skewing north to south for miles, then suddenly veering east to west near Hatteras Village, before turning once more in a southeasterly direction. Some of the islands are low and narrow, only a few feet above sea level, and especially vulnerable to winter Nor’easters and hurricanes in summers. The warm waters of the Gulf Stream and colder Labrador Current collide just miles offshore, creating dangerous shoals and some of the largest waves along the East Coast. Over many centuries, scores of inlets have opened and closed on the Outer Banks, while the barrier islands have slowly migrated landward as sand has washed across shorelines and flats on the oceanside and marshes have expanded along the backside, according to one federal study.

Despite these risks, developers continue to add billions of dollars of real estate, from Corolla in the north to Ocracoke Village in the south, making the Outer Banks the fastest-growing section of the North Carolina coast. Property values have also soared to an all-time high. Dare County, which includes thousands of beach homes, recently valued all of its property at nearly $18 billion, while the value of ocean property in smaller Currituck County has ballooned to almost $5 billion.

“It’s as if no one cares,” says Danny Couch, a Dare County Commissioner, real estate agent and sometimes tour guide. “A lot of people have so much money they don’t care about the risk.”

In the last decade alone, DOT has spent nearly $80 million dollars to keep hazard-prone NC 12 open for the year-round residents of the lower Outer Banks. That includes rebuilding the S-Curves three different times, but doesn’t include the cost of three new bridges needed to traverse inlets opened by storms or to bypass the rapidly eroding shoreline. Together, the bridges push the cost of maintaining NC 12 to about a half-billion dollars.

Asked if there were another highway as vulnerable as NC 12, Colin Mellor, a DOT environmental specialist, shuffled around a bit before answering: “No, emphatically, is the answer. NC 12 is a poster child nationwide, if not worldwide,” he said. “It’s a North Carolina route on a ribbon of sand that jumps out into the ocean.”

Tumbling Into the Ocean

This spring, two vacation homes in the Trade Winds Beaches subdivision of Rodanthe crashed into the ocean during a storm. One bobbed like a cork in the rioting surf until a wave grabbed ahold of it and smashed it to pieces. That evening film of the collapse spiraled onto national television. In a blog entry, local photographer Michael Halminski wrote that the experience “reminded me of the Wicked Witch getting splashed with water and melting away.”

Cottages have been tumbling into the ocean for as long as humans have been building along the Outer Banks. The difference now is that they appear to be falling in at a faster rate, and scores of homes are now at risk. Halminski estimates that he’s seen about 50 houses destroyed since the 1970s. Mike Bryant recalls entire rows of vacation houses vanishing into the surf in multiple storms. In South Nags Head, on Seagull Drive, a half-dozen beach houses squatted in the ocean for years until they were eventually purchased by the town as part of a 2015 lawsuit.

In each instance, the culprit was erosion, which appears to be worsening along large stretches of the Outer Banks. Areas of Rodanthe have retreated over 200 feet in the last two decades, and are currently losing about 13 feet of beach per year, according to estimates by the National Park Service, which manages the Cape Hatteras National Seashore. Michael Flynn, an NPS scientist, likened the erosion to a checkbook overdraft, with not enough sand to protect the houses. “Now, with sea level rise, it seems to be getting worse,” he said, “allowing lesser-intensity storm waves to run up the beach.”

Dare County, which includes Rodanthe, recently tagged nearly 20 beach houses near the Trade Winds subdivision as unsuitable for use because of problems ranging from damaged septic systems to wobbly pilings and broken steps. But the county lacks the legal authority to condemn the houses and doesn’t have a fund to buy risky properties. Even if it did, it’s unlikely many owners would retreat, “which no one wants to do,” said Bobby Outten, the county manager.

That’s not to say, Dare County doesn’t follow a different type of retreat. “It’s a Darwinian form of retreat,” says Danny Couch. “Houses fall in one at a time.”

A Temporary Solution

Barrier islands are always in motion, growing and shrinking, depending on sea level, wind direction, storm surge and other factors. In that sense, erosion is a natural phenomenon and only becomes a problem when humans build too close to the water and then try to hold a line that nature never meant to hold.

That is more or less the situation of the Outer Banks and scores of other barrier islands up and down the East and Gulf coasts. A land boom that began here in the 1950s has added thousands of second homes along the oceanfront and sounds, even as the shorelines and marshes are washing away. Property owners and politicians insist that there is too much money at stake to walk away now. Indeed, the windfall from the beaches has helped to transform these North Carolina counties from poor and rural outposts into two of the state’s richest and fastest-growing regions, with property on the Outer Banks accounting for 60 percent of the tax revenues of Dare and Currituck counties.

“The reality is we depend on tourism, and no one wants to give that up,” says Couch. “So, what we have to do is to learn how to live smarter and adapt to the changes.” One way Dare County is adapting is by embracing a multimillion-dollar plan to replenish its eroding beaches with millions of yards of sand pumped from dredges positioned offshore. The sand helps provide some protection and keeps the tourists happy. But sand is only a temporary solution, and powerful Nor’easters and hurricanes can gouge an artificial beach in just hours.

All of which means, once you begin to pump sand, you pretty much commit to keep pumping, a lesson the town of Nags Head has learned. This year, the popular resort is embarking on its third round of beach repairs since 2011, when it initially pumped nearly 5 million cubic yards of sand onto its beaches at a cost of $36 million. Hurricanes in 2018 and 2019 swept away much of that sand, and this month the town began pumping sand again along 4.5 miles of shoreline at a cost of nearly $14 million. Meanwhile, the Dare County villages of Duck, Southern Shores, Kitty Hawk, Kill, Devil Hills, Avon and Buxton also will be pumping sand through this fall.

One community that isn’t getting sand is Rodanthe. That may seem counterintuitive, but there is an explanation. The community is getting a bridge instead, built in the Pamlico Sound behind the barrier island and extending 2.4 miles to the southern end of the Pea Island National Wildlife Refuge. Built at a cost of $155 million (80 percent federally funded), the Jug Handle Bridge bypasses the highly erosive S-Curves area of NC 12 and should eliminate DOT constantly having to rebuild the highway. In fact, that stretch of road is slated to be torn up this fall, allowing the ocean to once again wash over the sand and marsh, restoring the area to its natural form.

Last year, Dare County created the NC 12 Task Force to study ways to protect its endangered highway. The group includes representatives from federal and state agencies and is updating reports done by previous study groups. “There have been multiple task forces called whatever they were called and multiple reports over time,” said county manager Bobby Outten. “Frankly, the issues and hot spots haven’t changed all that much. What has happened is that the risk level or the threat level has increased some.”

In the early 2000s, one group unanimously recommended building a 17-mile-long bridge in the Pamlico Sound bypassing all of Pea Island and several additional hot spots along NC 12. But the plan collapsed after local politicians objected, saying the long bridge would make it harder for visitors to use the islands. They recommended a new, shorter bridge over the volatile Oregon Inlet that opened in 2019 at a cost of $250 million dollars. A third bridge, built after a hurricane cut an inlet through an especially vulnerable section of Pea Island, cost millions more.

Outten said the up-front expense of building one long bridge to bypass multiple hot spots would be prohibitive. It would be cheaper and faster to spread the cost of multiple bridges over time, in effect creating an archipelago akin to the Florida Keys. “The idea is to troubleshoot solutions,” he said, “then to go to DOT and our federal legislators in Washington and tell them we need to do something.”

Geologist Stanley Riggs, who for decades was based at East Carolina University and has probably studied the Outer Banks more than any other researcher, said even a series of short bridges may not be enough with rising sea levels and more powerful storms in our overheated future. “I don’t see how this ends well,” he said. “They’re trying to preserve a coastal economy that was built on a pile of shifting sand and in the long run has a high probability of failure.”

Gilbert M. Gaul is a two-time Pulitzer Prize winner and author of the new book The Geography of Risk: Epic Storms, Rising Seas and the Cost of America’s Coasts, published in 2019.