Hard Engineering: Rivers

• Outline the main hard engineering strategies for rivers:

  • Dams/Reservoirs
  • River Straightening
  • Embankments
  • Flood Relief Channels
• What is hard engineering in a river?

  Involves man-made, built structures designed to control the flow of rivers and reduce flooding
• What are the costs and benefits of dams and reservoirs?

  Benefits:

  • Store large volumes of water.
  • Regulate river flow and reduce flooding.
  • Can generate hydroelectric power (HEP).

  Costs:

  • Very expensive to build and maintain.
  • Can flood farmland and displace people.
  • Interrupt natural sediment flow downstream.

  
• What are the costs and benefits of river straightening?

  Benefits:

  • Water flows faster away from flood risk areas.
  • Reduces the risk of localised flooding.

  Costs:

  • Increases flood risk downstream.
  • Can damage habitats and reduce biodiversity.
  • Expensive and unnatural-looking.

  
• What are the costs and benefits of embankments?

  Benefits:

  • Increase river channel capacity.
  • Protect land and properties behind the embankment.

  Costs:

  • High construction and maintenance costs.
  • If they fail, flooding can be worse.
  • Can look unattractive and block natural views.

  
• What are the costs and benefits of flood relief channels?

  Benefits:

  • Divert excess water away from urban areas.
  • Can protect high-value land and infrastructure.

  Costs:

  • Expensive to build and maintain.
  • Can flood other areas if not well designed.
  • May disrupt farmland and habitats