administer the National Shoreline Erosion Control Development and Demonstration
Program, (hereafter called the Section 227 Project) which demonstrates prototype-scale
"innovative" or "non-traditional" methods of shoreline erosion control and evaluates the
effectiveness of these devices or methods. This research and development effort has
three primary objectives, 1) to assess and advance the state of the art of beach erosion
control technology, 2) to encourage and achieve the development of innovative solutions
to beach erosion control and 3) to communicate the findings to the public and to further
the use of well-engineered alternative approaches to beach erosion control.
Under this R&D initiative, several projects are underway on all four coasts of the
US. The first of these demonstration projects is located at Cape May Point, NJ, the
southern-most beach along the New Jersey shore. The Engineering Research and
Development Center's (ERDC) Coastal and Hydraulics Laboratory (CHL) and the
Philadelphia District (NAP) have planned, designed, and constructed a Demonstration
Project to assess the use of prefabricated concrete structures for erosion control. The
proposed plan for the Demonstration Project was developed through coordination with
U.S. Army Corps of Engineers, Headquarters (HQ), the Coastal Engineering Research
Board (CERB), the State of New Jersey Department of Environmental Protection
(NJDEP) and local interests at Cape May Point. NJDEP has agreed to participate as the
non-Federal sponsor for the Demonstration Project.
The beach at Cape May Point covers a 1.8 km length of shore along the north side
of the entrance to Delaware Bay and thus the beaches have both characteristics of an
open Atlantic Ocean beach as well as an estuary beach setting. The Borough of Cape
May Point is bordered on the east by a freshwater wetland called Cape May Meadows
and the City of Cape May (Figure 1). Cape May Inlet is located on the northeast border
of Cape May City. The beachfront at Cape May Point has experienced erosion that is
threatening the 4.5 m high primary dune and upland structures located behind the dunes.
Waves break on the beach from the east to south from waves originating in the Atlantic
Ocean and from the south to west from waves originating across the 26 km fetch of the
mouth of Delaware Bay. Wave heights average 0.6 m in the summer and 1.2 m in the
winter, with higher waves common during storms. The mean semidiurnal tide range is
1.46 m. In addition to wave activity, a north marginal flood channel parallels the shore
and is just 182 m offshore of the beachfront. Flood tidal currents in this channel, at
maximum, are estimated to be on the order of 0.77 m/s. The net sediment transport is
approximately 153,000 m3 per year to the west into the Bay and is a function of angle of
wave approach as well as predominantly bayward tidal flow along this marginal flood
channel just off the beach (USACE, 1997). The ebb flow out of Delaware Bay is mainly
confined to an ebb channel located further offshore.
Beach and dune erosion has been a problem at Cape May Point for some time due
to this interaction between waves and tidal currents. Over a period from 1879 to 1943,
the shoreline generally eroded. Between 1924 and 1929, after construction of jetties at
Cape May Inlet to the east, the City of Cape May built 24 groins to slow an erosional
trend progressing along the coast from east to west. In 1930, a steel sheet pile bulkhead
was placed between the existing timber cribs along the beachfront of Cape May City.
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