4.2 - Soft Engineering Flashcards
What do soft engineering solutions do?
They work with natural systems to reduce coastal erosion and flood threat and they help to protect vital natural ecosystems
What is beach nourishment?
It is artificially replacing the sediment that has been lost by erosion / LSD
When is beach nourishment used?
It is used to enlarge the beach to attract tourists and dissipate the wave energy further from backshore
How much does beach nourishment typically cost?
It usually costs £2million per km squared
What are 2 disadvantages of using beach nourishment?
It needs to be replaced every few years and it can cause issues if it is dredged from within the sediment cell as it removes material from the system
What is cliff stabilisation?
It is regrading the cliff to a lower angle of rest to provide stability
What is one advantage of cliff stabilisation?
It provides more certainty for property owners
What is the purpose of cliff drainage?
To drain water out between permeable and impermeable layers of the cliff
What is a disadvantage of cliff drainage?
It usually isn’t visible, inevitably disturbs the cohesion of the rock layers and therefore only reduces mass movement and doesn’t prevent it
What does regrading do?
Creates a more stable slope angle
What is a disadvantage of regrading?
The slope angle has to be absolutely right and still needs cliff drainage and vegetation planting
What is an advantage of protecting dunes?
They are very effective at coastal defence - wave energy absorption and offers protection from flooding
What is dune stabilisation?
It is a combined, low-impact, low-cost approach of stabilising bare sand with old trees and fencing, replacing marram grass, adding boardwalks to reduce trampling and educating tourists with info boards
