Both sides agree the bridge is long overdue for replacement. Natural forces have caused Oregon Inlet and the refuge portion of the island to shift position since the bridge was completed in 1962. Hatteras Island is migrating inland at a rate of five to 22 ft per year.

Environmentalists have long favored construction of a 17.5-mile replacement bridge through Pamlico Sound that would bypass the wildlife refuge entirely. FHWA deemed that option unpractical as it would require construction estimated to cost as much as $1.4 billion.

The result, according to a 2010 environmental report, “would create a unique maintenance problem of extraordinary magnitude for NCDOT as it would have to defer much-needed improvements on the remainder of the state highway system in North Carolina for a significant period of time.”

But the long-bridge option came up short last year when NCDOT asked for the public's input. Thanks in part to a Facebook-based campaign orchestrated by an informal group called the “Bridge Moms,” 95% of the more than 3,800 comments submitted from across the country endorsed NCDOT's preferred alternative of the less-expensive, parallel bridge.