Lifeline built on shifting sands

Waves hit a new bridge on Highway 12 at Pea Island, N.C. North Carolina - Agencies Last August, when Hurricane Irene sliced across the Outer Banks, it cut Highway 12, Hatteras Island’s lifeline, in two places. Engineers rushed to repair the damage, filling and repaving a washed-out stretch of roadway here and building a bridge over a newly formed inlet a few miles to the north. The road reopened on Oct. 11, to the cheers of anglers, would-be vacationers and the innkeepers, restaurateurs and merchants whose livelihoods had taken a huge blow. But the winds and waves that shape the coast were already gnawing at the new bridge. By January, engineers were reinforcing its southern approach with sandbags and rock trucked in from the mainland, in hopes of keeping the road open until a more permanent fix could be designed and built. The Outer Banks are home to some of the nation’s most celebrated beach communities. The road that links them, also called N.C. 12, offers an extreme example of the difficulty of maintaining houses, condos, roads and other infrastructure in the face of a climate-driven rise in sea level. By some estimates, at least 70 percent of the ocean coastline of the lower 48 states is threatened by erosion. But the outlook here is unusually gloomy. In 2009, a federal report on erosion in the Middle Atlantic states predicted that if the sea level rises two feet this century — an estimate that many experts call optimistic — “it is likely that some barrier islands in this region will cross a threshold” and begin to break up. The report, produced by the Environmental Protection Agency, the United States Geological Survey and other agencies, said the Outer Banks were particularly threatened. Already, Highway 12 floods repeatedly and is often cut by storms. Maintaining it “is totally a lost cause,” said Stanley R. Riggs, a coastal scientist at East Carolina University who is an author of a new book, “The Battle for North Carolina’s Coast,” which describes in depressing detail the difficulties of keeping the road open. “It will bankrupt the state,” he said. But people who live and work on the Outer Banks say abandoning the road would make life impossible. “You would see people with nothing left,” said Eddie Williams, who was born and raised on Hatteras Island. He manages the Paint Box, a gift shop in the village of Hatteras. “It would be devastating,” he said. Beth Smyre, an engineer for the State Department of Transportation who is leading the planning effort, acknowledged the pessimism coastal geologists bring to the issue. “We try to take into account all these different opinions,” she said. But she added: “There are people living out there, there are tourists visiting out there. We have to provide a reliable and safe transportation system out there.” According to a 2011 state report, coastal tourism brought $2.6 billion to the state’s economy in 2009, supporting 50,000 jobs. “We have an obligation to keep this access in place,” Jerry Jennings, a district engineer with the transportation department who had overall charge of the road repairs, said in October, as he watched crews put the finishing touches on the $11 million-plus repair projects he described as temporary fixes. He added, “Our employees, fortunately or unfortunately, have a lot of experience dealing with Highway 12.” Irene’s attack on Highway 12 came as North Carolina was already confronting a number of issues relating to the fate of the Outer Banks. Last summer, the state confronted what engineers called “advanced deterioration” of the Herbert C. Bonner Bridge, which carries the highway from Nags Head to the Pea Island National Wildlife Refuge, on the north end of Hatteras Island. Some geologists suggested replacing the bridge with a system of ferries from the mainland. Others suggested maintaining a road link with a causeway or “long bridge,” looping into Pamlico Sound, an idea that the federal Fish and Wildlife Service endorsed as the best long-term option. The state opted for a replacement bridge that will run right alongside the existing span; planning is under way. Robert S. Young, a coastal geologist who is head of the Program for the Study of Developed Shorelines at Western Carolina University, calls the project “our own little bridge to nowhere.” “They can engineer that bridge so well that it can withstand a Category 3 or 4 hurricane,” Dr. Young said in a telephone interview. “The barrier island it is connected to cannot.” North Carolina has long been a leader in coastal protection through its ban on coastal armor — like seawalls and revetments — which, while it may protect a particular house or condo, almost inevitably degrades or even destroys sandy beaches. But last summer the State Legislature voted to loosen that prohibition, allowing owners of threatened buildings to protect them with “terminal groins,” structures built out into the surf to trap sand.