Energy Level : The level of potential erosive wave energy due to waterbody width ( e . g ., fetch ), shoreline orientation , and boat traffic is an important factor in choosing an appropriate living shoreline approach . Examples of areas with higher erosive wave energy due to wind / wave or wake are wider water bodies , dredged channels , and high boat traffic areas . Examples of areas with higher erosive wave energy due to currents are the outside bend of a river or large tidal creek , and sites located on a straightaway or inner bend of a creek . An example of areas with lower erosive wave energy is smaller sheltered waterways .
Bank Slope and Width : To determine where to place materials , you need a calculated slope for the portion of the bank where the living shoreline will be installed . This is the horizontal distance from the low water line to the marsh edge . Note that if the slope is high and the sediment composition is muddy ( high silt / clay ), the potential for materials to slide down the bank increases . See Figure 30 for determining bank slope and width .
Figure 30 : Determining the slope of tial creek banks
Escarpment : An escarpment is the erosional area of a shoreline that has some degree of vertical relief ( steep slope ), and can be often located at a marsh edge . A scarp face along a shoreline is usually an identifier of an area in need of stabilization , as it experiences heavy erosion . This amount of erosion is related to the overall energy in the system , and therefore requires a sturdy living shoreline technique as the height of the escarpment may affect a treatment ’ s performance in terms of its ability to retain sediment .
Sediment Firmness and Composition : The sediment firmness , sink depth , and composition determines which living shoreline material will be most suitable . Softer sediment often requires the use of additional materials to prevent slippage down the bank or to prevent excessive sinking of materials . See Figure 31 for a simple technique for determining sediment firmness .
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NATURE-BASED SOLUTIONS MANUAL FOR KIAWAH ISLAND