The elevations of maximum average erosion and accretion correspond rea- 
sonably well with the maximum water elevation. Maximum erosion occurred 
at, or slightly above, the maximum water elevation; maximum deposition 
was observed below this elevation. On those beaches where maximum ero- 
sion occurred at significantly high elevations (principally Cape Cod), 
the loss was probably due to slumping of material from scarps made unstable 
by wave scour at the scarp base. 
Because the storm moved rapidly northward (Fig 2), the accompanying 
surge was effective through less than two tidal cycles. 
VII. CONCLUSIONS 
1. As a result of the 17 December 1970 storm, 80 percent of 89 sur- 
veyed profile lines suffered an average net volume loss of 6.5 cubic yards 
per foot, between MSL and the maximum elevation contour surveyed for each 
profile line. (These data omit profile lines 06 on Cape Cod and 12 on 
Long Beach Island which appear questionable.) Storm intensity is expected 
to be equaled or exceeded about twice a year. 
2. The maximum recorded erosion was 21.7 cubic yards per foot on 
Cape Cod profile line 01, which included loss from the cliff behind the 
beach. The maximum recorded accretion was 24.4 cubic yards per foot at 
the Atlantic City profile line 01, which is immediately adjacent to the 
Absecon Inlet jetty and in an area of a beach fill made a few months 
earlier. 
3. The larger vertical changes in sand level (4 to 5 feet) were 
observed on the coarser, steeper beaches of Cape Cod and Long Island; the 
maximum horizontal change in the MSL contour of -96.3 feet was observed 
on the finer, flatter beaches of Ludlam Island. 
4. Profile contours of maximum erosion correlated reasonably well 
with maximum water elevation obtained from tide and surge data and were 
generally between +4 and +8 feet MSL. Accretion was generally observed 
near the MSL contour, except at Ludlam Island, where eolian accretion in 
the dunes was more significant. 
5. Extrapolation from surveyed profiles indicates that a minimum of 
10.1 million cubic yards of sand was moved from the beach above MSL along 
about 450 miles of ocean front between Cape May, New Jersey, and Race 
Point, Massachusetts, as a result of this storm. This volume, equivalent 
to 4.4 cubic yards per foot, compares with 3.2 to 9.5 cubic yards per 
foot computed by Shuyskiy (1970) for a storm in the eastern Baltic Ocean 
in October 1967. Data from Harrison and Wagner (1964) indicate that the 
average erosion of the dunes at Virginia Beach, during the March 1962 
storm, was on the order of 4.4 cubic yards per foot. For four storms at 
Atlantic City between November 1963 and February 1972 (including the 17 
December 1970 storm) an average loss of 5.2 cubic yards per foot per storm 
was estimated, based on BEP surveys (Everts, DeWall, and Czerniak, 1975). 
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