Soft Engineering and Hard Engineering
Hard engineering refers to the construction of physical structures to defend against erosive power of waves
To protect a coast from erosion, people have built seawalls in front of a cliff or along the coast. A seawall is usually made of concrete. It acts as a buffer and absorbs energy of breaking waves especially during storms where the waves are strong, thus protecting the coast. A seawall shields and protects the coast from the direct impact of the incoming waves, thus reducing erosion. However, a seawall may not protect a coast from erosion in the long run. As waves break against the seawall, the energy from the waves is redirected downwards, to the base of the seawall, resulting in a strong backwash. The backwash erodes the beach beneath and wears away the base of the seawall, causing it to weaken and eventually collapse. Hence seawalls have to be carefully maintained. It is also expensive to build seawalls. One example is the seawall at Galveston, Texas, USA. It was built for protection of the city after the 1900 hurricane. Another example is the seawall in Vancouver, Canada. It is a stonewall that was constructed around the perimeter of Stanley Park to prevent the erosion of the park’s foreshore. It was built because the waves created by ships passing through the area were eroding the coast.
In some coastal areas, people have built breakwaters off the coast but parallel to it in order to protect the coast from high-energy waves. A breakwater is usually made of granite. It creates a zone of sheltered water between itself and the coast, so that waves will break against it before reaching the coast. The calm waters will deposit materials, forming beaches. Calm waters generate further material deposition for beach accretion or beach build-up. However breakwaters are unable to provide full protection as they still leaves areas of the coast unprotected. The unprotected areas will be prone to erosion. Besides, protection on one part of the coast causes problems
To protect a coast from erosion, people have built seawalls in front of a cliff or along the coast. A seawall is usually made of concrete. It acts as a buffer and absorbs energy of breaking waves especially during storms where the waves are strong, thus protecting the coast. A seawall shields and protects the coast from the direct impact of the incoming waves, thus reducing erosion. However, a seawall may not protect a coast from erosion in the long run. As waves break against the seawall, the energy from the waves is redirected downwards, to the base of the seawall, resulting in a strong backwash. The backwash erodes the beach beneath and wears away the base of the seawall, causing it to weaken and eventually collapse. Hence seawalls have to be carefully maintained. It is also expensive to build seawalls. One example is the seawall at Galveston, Texas, USA. It was built for protection of the city after the 1900 hurricane. Another example is the seawall in Vancouver, Canada. It is a stonewall that was constructed around the perimeter of Stanley Park to prevent the erosion of the park’s foreshore. It was built because the waves created by ships passing through the area were eroding the coast.
In some coastal areas, people have built breakwaters off the coast but parallel to it in order to protect the coast from high-energy waves. A breakwater is usually made of granite. It creates a zone of sheltered water between itself and the coast, so that waves will break against it before reaching the coast. The calm waters will deposit materials, forming beaches. Calm waters generate further material deposition for beach accretion or beach build-up. However breakwaters are unable to provide full protection as they still leaves areas of the coast unprotected. The unprotected areas will be prone to erosion. Besides, protection on one part of the coast causes problems