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Undisturbed by man , soil is usually covered by shrubs and trees , ead and decaying leaves , or a thick mat of grass . Whatever the vegetation , it protects the soil when rain falls or wind blows . Root systems of plants hold soil together. Even in d ought , the roots of native grasses , which extend several feet into the ground , help tie down thm. soil and keep it from blowing away . With the vegetation cover stripped away , soil is vulner ble to damage . Whether through cultivation , grazing , deforestation , burning , or bulldozing , once the soil is bare to the erosive action of wind and water, the slow rate of natural erosion is greatly increased . Losses of soil take place much faster than new soil can be created . With the destruction of soil structure , eroded land is even more susceptible to erosion . The occurrence of erosion has greatly increased . This is because of the activities of modern development and population growth , particularly agricultural intensification . It also is in the field of agriculture that most efforts have been made to conserve soils , with mixed success ( Union of International Associations , 1999 ) . Particles scattered by erosion can also cause problems elsewhere . Stormwater drainage systems , both natural and mechanical , are frequently clogged by loose sediment. If drainage systems are not cleared of uncontrolled sediment on a regular basis , they lose function . 4. 1 . 8. 2 Beach Erosion Hazard Identification . Wind , waves , and long shore currents are the driving forces behind coastal erosion . This removal and deposition of sand permanently changes beach shape and structure ( Sea Grant Haznet , 1998 ) . Most beaches , if left alone to natural processes , experience natural shoreline retreat. As houses , highways , seawalls , and other structures are constructed on or close to the beach , the natural shoreline retr at processes are interrupted . The beach jams up against these man- made obstacles and narrows considerably as the built-up structures prevent the beach from moving naturally inland . When buildings are constructed close to the shoreline , coastal property soon becomes threatened by erosion . The need for shore protection often results in " hardening " the coast with a structure such as a seawall or revetment. A seawall is a large concrete wall designed to protect buildings or other man - made structures from beach erosion . A revetment is a cheaper option c nstructed with " rip rap " such as large boulders , concrete rubble , or even old tires . Although hese structures may serve to protect beachfront property for a while , the resulting disruption of the natural . coastal processes has serious consequences for all beaches in the area . Se walls inhibit the natural ability of the beach to adjust its slope to the ever- changing ocean wave conditions . Large waves wash up against the seawall and rebound back out to sea , carry ring large quantities of beach sand with them . With each storm , the beach narrows , sand is lost to deeper water , and the long shore current scours the base of the wall . Eventually , large waves impact the seawall with such force that a bigger structure becomes necessary to continue to resist the forces of the ocean ( Pilkey and Dixon , 1996 ) . Historic Events. Both Hurricanes Floyd and Irene caused significant beach erosion along the Atlantic Ocean . Oceanfront property in the City of Vero Beach , Town of Indian River Shores , and Town of Orchid also experienced beach erosion during these two events . 4-44