Oregon Inlet, 2011: How we got here

DURHAM — Within the next few years, Oregon Inlet will likely be permanently closed except to the smallest of recreational boats. Trawlers will have to use Hatteras or Ocracoke inlets or perhaps move to Norfolk, Va. In any event, a way of life must change on the Outer Banks and it’s all due to a series of mistakes that didn’t need to happen.

Mistake No. 1 Construction of a fixed bridge across an inlet known to be rapidly migrating, as evidenced by the Bodie Island lighthouse stranded 2 miles away from the inlet.

Mistake No. 2 Completing the Bonner Bridge (in 1963) even though nature dropped a hint by destroying the just-constructed abutments during the 1962 Ash Wednesday storm that caused the inlet to widen overnight from one-half mile to 2 miles.

Mistake No. 3 Putting the navigation channel where all large vessels entering and exiting Pamlico Sound must pass under a fixed span of the bridge. Sand pouring into the inlet from the north has finally reached a volume too large to economically dredge from this immovable channel.

Mistake No. 4 The decision by Congress in 1970 authorizing the U.S. Army Corps of Engineers to build two 2-mile-long jetties to improve navigation and allow passage of larger vessels. This would lead to an increase in the catch size of a fishery resource already in serious decline. The jetties were strongly opposed by the Department of the Interior and the environmental/marine science community, which argued that the Corps’ environmental impact statements were wrong.

Mistake No. 5 During the 30-year debate over the jetties, the Corps encouraged the local fishing industry to invest in large trawlers that now can’t make it through the inlet.

Mistake No. 6 In 1982, the Corps for the first time began offshore dumping of sand dredged out of the inlet by hopper dredging. (Previously, dredged sand cleared from the channel was disposed of within the inlet.) The next year, the southward migration rate of Oregon Inlet jumped from about a few feet per year to 300 feet per year on the Pea Island (south) side of the inlet. This led directly to the next mistake.

Mistake No. 7 The 1990-1991 construction of a $16 million, 3,000-foot-long jetty (called a terminal groin), built by the state Department of Transportation to protect N.C. 12. The Corps of Engineers’ Wilmington District declared a finding of no significant environmental impact from the jetty.

Robert Dolan, a coastal geologist at the University of Virginia, termed the environmental impact document “the most overstated, verging on dishonest statement, that I’ve seen. ….However, in this case, and as in dozens of other Corps projects, when it turns out that this terminal groin does not work as claimed, no one in the Corps will be discredited – it will all be forgotten and another cycle of corrections will be instituted.”

Dolan was right. Indeed the terminal groin did not work as claimed for the downdrift ocean shoreline of Pea Island. Erosion has required more than 10 million cubic yards of sand to be pumped just on the 2-mile stretch of beach south of the inlet, with erosion rates up to 13 feet per year continuing farther south on Pea Island. This ongoing erosion on Pea Island has cost North Carolina’s Department of Transportation many millions of dollars to maintain N.C. 12.

The terminal groin has led to additional clogging of the inlet, since sand exchange across the inlet is now halted. Now, in 2011, the end is near. The channel has been declared by the Coast Guard to be unsuitable for large vessels, the very vessels whose construction was once encouraged by the Corps.

Mistake No. 8 The state’s proposed replacement bridge over the inlet will not change a thing.

The time has come for the state DOT to take an immediate and fresh look at the solution to the bridge replacement project and the potential closure of the inlet and its impact on tourism and fishing. It’s time to look at a new type of bridge that will allow the inlet to migrate. Or better yet, solve the problem for the long term by the use of ferries instead of bridges.

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

Read more: http://www.newsobserver.com/2011/04/26/1153673/oregon-inlet-2011-how-we-got-here.html#ixzz1LWyClsM7