Figure 6. Moriches Inlet breach fill construction nearing completion, 4 December 1980.
Westhampton Beach, New York. In December 1992, a northeast storm breached the barrier
island at Westhampton, Long Island, NY, from the ocean side approximately 3 miles east of
Moriches Inlet, just downdrift from the Westhampton groin field (Terchunian and Merkert
1995). The island breached at two locations. The first, called Pikes Inlet, reached a width of
more than 1,000 ft and was initially larger than the second breach called Little Pikes Inlet. Little
Pikes began as a shallow 100-ft wide breach that could be traversed by foot over peat deposits.
By February 2003, Pikes Inlet was closing naturally by sand transported alongshore, and the
USACE New York District completed the closure with sand dredged from a channel north of the
breach. Little Pikes Inlet, however, continued to grow because it was located just 1,000 ft from
the end of the groin field updrift that reduced sediment transport. The closure of Pikes Inlet
increased the tidal flow through Little Pikes, and the breach grew to a width of more than
3,000 ft with maximum depths of approximately 18 ft. The breach erosion created extensive
flood and ebb shoals, as well as wing spits.
The New York District initiated emergency measures to close the breach in August 1993. The
method selected to close the breach was similar to that applied to close the 1980 Moriches Inlet
breach. Two sheet pile walls were to be constructed 20 ft apart and parallel to one another along
the center of the island. The seaward wall was a permanent structure to protect against future
breaching. The bayside wall was to be temporary and reduce sand losses during the filling
operation. Sand from an offshore source was pumped to a staging area at the east end of the
breach. The filling operation proceeded from the staging area with a 30-inch pipeline dredge
capable of pumping 20,000 to 50,000 cu yd per day.
The initial fill method was cumbersome because the dredge could pump at large capacity, but the
wall construction was slow. The engineers decided not to construct the temporary wall and
pump as much sand as possible. The new procedure worked well, and construction proceeded
with sand pumped on the seaward side of the permanent sheet pile wall to minimize sand
deposited the bay. The initial fill pass created a 20-ft wide berm and proceeded from east to
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