[AS Level ] Hard Engineering Techniques + Advantages and Disadvantages

[AS Level ] Hard Engineering Techniques + Advantages and Disadvantages

1. Embankments - Raised banks along the river

   • can be used as a path
     • concrete embankments can stop erosion
       • earth embankments provide habitats for wildlife
   • The banks are not always built high enough
     • Concrete embankments are ugly and unnatural

2. Channelisation - The river channel may be widened or deepened to allow it to carry more water. A channel may be straightened so that water can travel faster along the course,

   • effectively protects immediate areas because water is moved away quickly
     • Long lasting
   • altering the river channel may mean greater flooding risk as the water is carried there faster
     • Unnatural and visually intrusive

3. Storage Areas - A large area near the river that will fill with water if the river overflows, protecting the surrounding land.

   • Neded a large area of land that is not used
     • Only come into use when the river has flooded
   • Natural looking
     • Does not damage the environment

4. Dams - Built along the course of a river to control the discharge. Water is held back in a reservoir behind the dam and released in a controlled way.

   • Very expensive to build
     • sediment is often trapped behind the dam leading to erosion further downstream
       • Towns and farmland may be lost when the valley is flooded to form the reservoir.
   • Water in the reservoir can be used to generate electricity (Hydroelectric) or for recreation)

5. Flood Relief Channels - The channel course can be changed to take flood waters away from towns.

   • Makes people who live close the the main river safer as the flood water is taken away
     • can be used for water sports at other times
   • They use up a lot of land that might be difficult to buy if it is good farmland
     • Extremely Expensive

6. Flood walls - A vertical barrier made from concrete.

   • They have to be assembled carefully so that water does not get through the joints
   • Can be used in areas where they is not much space
     • easily and quickly erected using pre-constructed sections