Oregon Inlet jetties: The unjustifiable sequel in NC

Published July 10, 2014

by Orrin Pilkey, Professor Emeritus, Nicholas School for the Environment, Duke University, published in News and Observer, July 9, 2014.

Like a shambling zombie reanimated from the grave, a proposal to build Oregon Inlet jetties is once more with us. This, after an almost three-decade-long debate that ended with the “final” rejection of the jetties in 2002.

The originally proposed 2-mile-long rock jetties were intended to make navigation safer but were discredited at all levels: engineering design, economics, environmental and fisheries. Not in the recent history of the U.S. Army Corps of Engineers has such a major project been so thoroughly discredited.

To justify the $100 million price tag of the previously proposed jetties, the Wilmington Corps of Engineers District made the desperate assumption in 1976 that fishing vessels would come all the way from New England through Oregon Inlet to land a certain type of catch in Wanchese.

The National Marine Fisheries Service was concerned that the already stressed local fishery would be endangered by the use of the larger and more numerous fishing boats that the Corps predicted would come. Although the Corps claimed otherwise, it was clear to outside experts that the jetties as designed would steal sand from adjacent beaches, resulting in severe long-term erosion and flooding damage to the villages (Rodanthe, Waves, Salvo) south of the inlet.

The jetties would have been just another nail in the coffin of the already erosion-troubled N.C. 12. A so-called sand bypass system to move jetty-trapped sand to the south was deemed unworkable.

None of these problems with the proposed jetties has changed since the original plan was rejected.

The jetty project has been reborn because of serious channel maintenance problems caused by beach sand flowing into the navigation channel from the north. Today, the inlet is often closed to commercial fishing vessels

As a first step on a very long path to the new jetties, Republican state Sen. Bill Cook introduced Senate Bill 791 to allow the state to buy 500 or so acres of National Park Service land around the inlet as a construction site for the jetties. Cook and others have claimed that the National Park Service agreed to keep the inlet in good shape when it took over the land for the park but it “failed to uphold their promise.”

Not true. This false claim is being used to justify condemning federal land in order to to buy it. The state of North Carolina is the problem – not the National Park Service. To sweeten the pot for public acceptance, SB791 also provides for the creation of Oregon Inlet State Park out of the land it would purchase from the National Park Service. In other words, the state intends to buy a park to make a park!

The state’s first mistake in this saga was the 1965 construction of the Oregon Inlet bridge with a single high span for boat passage. In the face of a historic (from 1846 on) 75-to-100 feet annual southward migration rate of the inlet, this single static channel created by the bridge inevitably meant that extensive and expensive dredging would be required to keep the channel open and hold it permanently in place.

Sealing the fate of the navigation channel in the inlet is the 3,150-foot terminal groin that the state built in 1990 on the south side of the inlet at the north end of Pea Island. This trapped more sand within the inlet and created even more dredging problems.

It is possible to keep a healthy fishing industry through Oregon Inlet perhaps for generations to come. First and foremost the inlet must be allowed to migrate, which absolutely requires removal of the terminal groin. It also requires recognition that a proposed fixed bridge across the inlet won’t work because it, too, will require a lot of dredging to maintain a channel.

The inlet will then be free to migrate, and a channel will likely move with it, preserving the natural system that can survive and respond to sea level rise. The natural channel will require occasional dredging as was the case before the current bridge and the terminal groin were built.

Orrin H. Pilkey is James B. Duke professor emeritus in the Nicholas School of the Environment at Duke University.

http://www.newsobserver.com/2014/07/09/3995115/oregon-inlet-jetties-the-unjustifiable.html?sp=/99/108/