improvements from damage by major storms, the width may be determined as 

 the protective width which has been lost during storms of record plus the 

 minimum required to prevent wave action from reaching improvements. Where 

 the beach is used for recreation, justification for the increased width 

 of the beach may be governed by the area required for recreational use. 

 The current (1972) U.S. Government standard is 75 square feet of dry beach 

 per bathero Where the beach fill serves as a stockpile to be periodically 

 replenished, the berm should be wide enough to provide for expected re- 

 cession during the intervals between replenishment operations. 



5.334 Slopes . The toe of a stockpile of beach material should not extend 

 so deep that material on the surface of the stockpile would not be moved 

 alongshore in sufficient quantities by wave action. There is no firm 

 specification for this maximum depth, but depths of about 30 feet below 

 low-water datum on seacoasts and about 20 feet on the Great Lakes are 

 appropriate. The initial slope of any beach fill will naturally be steeper 

 than that of the natural profile over which it is placed. Subsequent 

 behavior of the slope depends upon the characteristics of the fill material 

 and the nature of the wave climate. In practice, the initial fill slope 

 is designed parallel to the local or comparable natural beach slope above 

 low-water datum. The design of the slope should be determined after care- 

 ful investigation of all pertinent data from low-water datum to about the 

 30- foot depth. The design slope is derived through synthesis and averaging 

 of existing data within and adjacent to the problem area, and is usually 

 significantly flatter than the foreshore slope. Design slopes based on 

 such data are usually in the range of 1:20 to 1:30 from low-water datum 

 to the intersection with the existing bottom. However, they are used for 

 computation of quantities only. It is unnecessary and usually impracti- 

 cable to grade beach slopes artificially below the berm crest since they 

 will be shaped naturally by wave action. Fills placed to a desired berm 

 width but with steep initial slopes will quickly adjust to a natural slope, 

 narrowing the berm and leaving the impression that much of the fill has 

 been lost, although it has only moved to establish the natural slope. 



5„335 Feeder Beach Location. Dimensions of a stockpile or feeder beach 

 are generally governed primarily by economic consideration involving com- 

 parisons of costs for different replenishment intervals. Therefore, 

 planning a stockpile location must generally be considered in conjunction 

 with stockpile dimensions. If the problem area is part of a continuous 

 and unobstructed beach, the stockpile is located at the updrift end of 

 the problem area. Until the stockpile material is transported by litto- 

 ral forces to the beach zone downdrift of the stockpile location, that 

 beach zone may be expected to recede at the same rate as determined from 

 historical survey data. If economically justified, stockpiles may be 

 placed at points along the problem area. Such placement decreases the 

 time interval between stockpile placement and complete nourishment of 

 the area. Stockpile lengths from a few hundred feet to a mile have been 

 employed successfully. If the plan involves a feeder beach just down- 

 drift from a coastal inlet, wave refraction and inlet currents must be 

 considered to locate the feeder beach so that a minimum of material is 



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