EM 1110-2-1100 (Part V)
31 Jul 2003
140
Combined Frequency Curve
120
Mean
90% confidence band
100
80
60
40
2
10
100
200
Return Period, yr
Figure V-4-18. Combined tropical and extratropical erosion-frequency curve
by translating the design profile at elevations between the design berm elevation and the depth of closure (see
Figure V-4-14) by an amount equal to the advance nourishment berm width. The sectional fill volume
required for initial construction (volume per unit length of shoreline) is calculated as the difference in cross-
sectional area between the preproject profile and the modified design profile shape. Example V-4-2 illustrates
calculation of sectional fill volume for a case where the preproject profile is in a severely eroded, unnatural,
condition.
(b) Advance nourishment beach width, and design berm width, might not have uniform values from reach
to reach within the project domain. Variations in the desired level of protection, assessment of long-term fill
evolution and renourishment requirements, and consideration of the potential for hot spot formation, will most
likely lead to alongshore differences in desired beach width. Therefore, the required sectional fill volume
also will vary by reach. Volume calculations for the entire project domain are made by summing results on
a reach-by-reach basis, where the volume requirement in a particular reach is calculated as the product of the
cross-sectional volume requirement and the length of shoreline in that reach.
(c) For the case of a healthy (sediment-rich), preproject beach profile and a fill material that has a median
grain size equal to that of the native beach sand, the volume V per unit length of shoreline required to produce
a beach width W can be estimated by
V ' W B%DC
(V-4-6)
Beach Fill Design
V-4-39
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