![]() Dredging is, first and foremost, an engineering technique employed for beach erosion control Dredging with barges uses the power of the barge to drag or pull ocean-bound barges filled with sand from offshore locations to beaches or along the coastline as needed for nourishment projects.The most common sand nourishment methods are dredging, beach dune restoration, and sand pumping. The sand is typically allowed to settle for a few weeks, and then it is smoothed and leveled.The sand, stones and shells are then spread along the coastline using bulldozers and rakes.Sand, stones, and shells are then usually pumped from offshore to the shoreline in a process known as bulkheading or pumping.The beach is first cleared of loose sediment.Here are few steps on How is beach nourishment done: Beach nourishment helps to restore balance to coastal ecosystems, which are in turn beneficial to the environment at large.Beach nourishment is advantageous to a wide variety of people, not only coastal residents but also visitors, people on vacation, and other beach-goers.Beach nourishment increases the durability of the protection systems.Beach nourishment is not harmful to the environment, but it does require extensive planning and coordination with local ecologists and government agencies that might be affected by the project.Beach nourishment is an inexpensive way to rebuild a beach and prevent beach erosion.Nourishment of beach sands mitigates longshore drift, a natural process that can result in the loss of sand from beaches.It might happen as a result of a variety of risks, such as a flood, a wildfire, or a drought. This could include the movement of a person, infrastructure (such as a building or a road), or a community. Managed retreat entails the deliberate, coordinated evacuation of people and buildings away from potential hazards. These structures, however, may be detrimental to the surrounding environment and in some cases may not effectively reduce shoreline erosion. Hard engineering typically involves the construction of seawalls, breakwaters, groynes, or revetments (i.e., structures that slow wave action). Soft engineering relies on natural processes and materials that are readily available and easily installed by manual labor or small construction equipment and is, therefore, more cost-effective in most situations. Soft engineering methods generally refer to natural shoreline protection approaches such as beach nourishment and sand dune restoration. Cape Hatteras Lighthouse.Coastal engineering for coastline protection entails the following: 1. change in policy from trying to defend coastal property to removing structures and allowing nature and the sea to reclaim coastal areas. Costly as sediment must be dredge from offshore or from harbors etc, transported to the beach and distributed. ![]() beach replenishment Sediment is added to the beach to replace what was lost. alternatives to hard stabilization construction restrictions, beach replenishment, and relocation construction restrictions stop construction in areas prone to erosion. To restore the situation, people must input in as much energy as they have misdirected through the modification - e.g. Human modifications of the shore can lead to large changes in sediment movement. May also lead to modification of sediment movement along the shore. breakwaters hard stabilization built parallel to the shoreline. Groins and groin fields change the distribution of sand on a beach, but do not retain more sand have the same effect as groins, as also structures built perpendicular to the shore jetties jetties may cause pronounced upstream deposition and downstream erosion. Eventually a groin field results as groins are built all along the beach. This can lead to the construction of another groin to protect downstream portion of the beach. ![]() Although a groin will trap sand on its upstream side, there will be a faster rate of erosion on the downstream side as this area will not be re-supplied with sand. Often built from rip-rap, large blocks of material. groin walls built perpendicular to the beach to trap sand and prevent it moving along the shore by longshore drift. Hard stabilization structures built to protect a coast from erosion or prevent the movement of sand along a beach Seawalls built parallel to the coast, not a good long term solution, and erodes recreational beaches. ways to protect the shore from erosion hard stabilization, seawalls, groin, jetties, and breakwaters. Tombolo sand ridge that connects an island or sea stack to the mainland. Bay barrier effectively cuts the bay off from the open ocean. Bay barrier or bay mouth bar forms if the spit extends across the bay and joins the mainland. Spit linear ridge of sediment that extends in the direction of longshore drift from the land into deeper water near the mouth of a bay. ![]()
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