A sea wall is a barrier against flooding by the sea. As sea levels rise because of melting glaciers, flooding from the sea is becoming more common. Experts recommend spending $416 billion to help protect American coasts from rising seas. However, no one wants to pay this bill. PBS News Hour argues why we need to spend more on sea walls.
The University of North Carolina Chapel Hill studied the effects of sea walls on storm surges from hurricanes.
Sea walls were effective at preventing damage, but it depended on what kind of sea wall was being used. Natural sea walls like shorelines, salt marshes, restored salt marshes, or oyster reefs offered the best protection. Man-made breakwaters made of stones also provided a good degree of protection.
What performed the worst were man-made sea walls and bulkheads.Manmade sea walls, although made to withstand strong waves, were useless to stop water flowing over them. Water then pushes back against the sea walls, causing them to buckle and collapse. Although most homeowners think that manmade sea walls are better than natural, they are wrong.
Natural shorelines were better at absorbing large amounts of water and breaking up wave velocity. They also require little to no repairs after major hurricanes like Hurricane Matthew. America does need to invest more in sea walls, but they should be natural sea walls.