morphologic evolution of the breach was monitored (Wamsley and Hathaway 2004). The
Hatteras breach had three distinct breach channels because of underlying peat deposits that
resisted erosion. Maximum current velocity through the main breach channel exceeded 6 ft/sec,
which scoured the channel to depths of approximately 20 ft.
The Hatteras breach destroyed utility infrastructure and severed North Carolina Highway 12
(NC12), isolating Hatteras Village from the rest of Hatteras Island. Parking lots and buildings
near the breach were also destroyed. NC12 is the only transportation route east from the village,
restricting access for residents and tourists. The Federal Emergency Management Agency
(FEMA), together with the local sponsor, the North Carolina Department of Transportation
(NCDOT), requested the Wilmington District to reestablish the land connection to Hatteras
Village as soon as possible. The breach closure operation required interagency cooperation,
coordination, and communication. A breach closure team was formed with representatives from
the USACE, FEMA, NCDOT, U.S. Fish and Wildlife Service, North Carolina Department of
Environment and Natural Resources, Coastal Area Management Agency, and the National Park
Service, which oversees the Cape Hatteras National Seashore where the breach was located. A
complete discussion of the breach closure is given by Wutkowski (2004).
The breach closure project was designed to build a berm along the alignment of NC12 of
sufficient width to allow the reconstruction of the highway and to build a dune system similar to
the pre-storm condition. The Wilmington District applied the lessons learned from the 1962
Buxton Inlet closure and based the design on that breach closure, which was just 10 miles to the
north. The closure of Buxton Inlet demonstrated that the Hatteras breach could be closed by
pumping material into the breach if the pumping capacity was sufficient. Based on the Buxton
Inlet pumping volumes, the minimum discharge capacity to close the Hatteras breach was
estimated to be between 9,000 and 18,000 cu yd per day. The fill material was medium-coarse
sand, which limited losses during the breach filling operation.
The breach was closed with an 11,300-hp, 30-inch dredge. The dredge also had a 7,200 hp
booster pump. The pumping capacity of this plant was greater than the minimum range of 9,000
to 18,000 cu yd/day. The filling operation started at the west breach bank, and filling was to be
accomplished by pumping from one side only. The eastern bank was composed of an erosion
resistant peat layer that allowed the design to omit armoring there. The peat layer was 3 to 4 ft
thick, several hundred feet wide, and was exposed at low tide.
The breach filling operation began on 17 October 2003. Two-thirds of the fill width was initially
constructed. The sand was discharged on the west breach bank along the center alignment of the
fill. Sand that accumulated at the discharge pipe was shaped by two bulldozers according to the
fill template. The first two channels of the breach and three-quarters of the main channel were
filled within 15 days. The first two channels filled quickly as they captured relatively little of the
tidal prism, and breach flow velocity was weak. The dredge averaged 15 hr/day of pumping time
with a production rate of 22,000 cu yd a day. The largest 1-day production was 41,000 cu yd.
On 1 November 2003, approximately 100 ft of the breach remained to be filled. Similar to
Buxton Inlet, as the cross-sectional area of the breach was reduced, the current velocity increased
and scoured much of the sand that was deposited, even with the large pumping capacity. To
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