reclamation projects where a fill is needed at a position in advance of the existing shore. Finally,
bulkheads are used for wharves and other navigational structures where greater water depth is needed
directly at the shore (Figure 7).
Construction of a bulkhead does not insure stability of a bluff. If a bulkhead is placed at the toe
of a high bluff steepened by erosion to the point of incipient failure, the bluff above the bulkhead may
slide, burying or moving the structure toward the water. To increase the chances of success, the
bulkhead should be placed away from the bluff toe, and if possible, the bluff should be graded to a flatter,
more stable slope.
Bulkheads may be either thin structures penetrating deep into the ground (e.g., sheet piling) or
massive structures resting on the surface (e.g., sand- and cement-filled bags). Simple sheet pile
bulkheads require adequate ground penetration to retain soil. They are generally used only where low
bulkheads are required. When higher structures are required, an anchoring system must be added to the
basic sheet pile section. Stacked bag structures do not require heavy pile driving equipment and are
appropriate where subsurface conditions hinder pile penetration. However, they need firm foundation
soils to adequately support their weight. Because they do not normally penetrate the soil, they often
cannot prevent slides where failure occurs beneath the surface. This generally limits their effectiveness
to sites where the backfill is relatively low.
Bulkheads protect only the land immediately behind them and offer no protection to adjacent areas
up and down-coast or to the fronting beach. In fact, their vertical faces may reflect wave energy, causing
increased scour in front of the structure. if downdrift beaches were previously nourished by the erosion
of land now protected, that land will erode even more quickly. . If a beach is to be retained adjacent to a
bulkhead, additional structures, such as groins or breakwaters, may be required.
Detailed information about specific bulkhead configurations is contained in APPENDIX A.
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