York District was requested to close the breach and began the filling operation in October of
1980. A monitoring program of the inlet and breach was conducted during construction of the
fill to ensure that the system was responding as expected. Several design modifications were
made during construction as a result of the monitoring program. A complete description of the
monitoring program is given by Schmeltz et al. (1982), and the construction procedures are
described by McCarthy et al. (1982). This breach was recently simulated with a numerical
morphologic model (Kraus and Hayashi 2005), for which further documentation on the evolution
of the breach width and depth is given.
The method selected for the breach fill included construction of two temporary sheet pile walls
30 ft apart and parallel along the bay side of the breach. The initial option of placing the sand
with no temporary retaining structures was discarded because of the potential for a high loss of
fill material as the operation was to take place during the winter storm season. In addition to
minimizing fill losses during construction, the expected advantages of the sheet pile walls
included control of tidal currents through the fill area and trapping part of the east to west littoral
drift. Construction of the retaining walls on the bay side of the breach provided protection from
wave attack and the bay side wall was further stabilized by driving short sheet pile spurs at right
angles to the main wall on the bay side.
Approximately half of the 1.2 million cu yd required to close the breach was obtained from an
upland source and the other half was acquired by bay dredging. The fill material from upland
sources was placed between the sheet pile walls and along the ocean side of the breach. The
dredged fill was placed between these two "protective arms" to minimize the loss of the dredged
sand while it was in a slurry state. Several weeks after closure operations began, a storm with a
two-year return period struck, damaging the exposed sheet pile walls and eroding some of the
fill. Engineers on site observed that without the sheet pile walls in place, the majority of the fill
would have been lost. By early December, the breach was nearing closure (Figure 6). To
facilitate the final closure, a sheet pile spur was constructed to deflect the ebb current away from
the breach and through the inlet. As a result, sand began to naturally accumulate in the breach,
and it was closed on 15 December. Sand placement continued through January of 1981, and the
sheet pile walls were removed with construction activities complete by the beginning of
February 1981. Material losses were approximately 15 percent of the total placed, including
losses from the storm. Subsequent to the closure, New York State constructed a rubble
revetment on the bay side of the barrier island contiguous with the jetty and running along the
bay shoreline of the barrier island.
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