Coastal Management Flashcards
Hard engineering
Involves man made structures that aim to prevent erosion. They are effective but are high cost and have significant environmental impact. By reducing erosion in one area of the coastline it may exacerbate it elsewhere
Soft engineering
Aims to work with and complement the physical environment by used natural methods of coastal defence. They are useful for protecting against sea level change as well as coastal erosion
Hard engineering - Offshore Breakwater
Rock barrier that forces waves to break before reaching the shore
+ effective at reducing waves energy
- visually unappealing
- navigation hazard
Hard engineering - Groynes
Timber or rock protrusions that trap sediment from LSD
+ cost effective
+ builds up beach
- deprived areas downwind of sediment increasing erosion elsewhere
Hard engineering - Sea Walls
Concrete structures that absorb and reflect wave evergreen with curved surface
+ promenade has tourism benefits
+ effective erosion prevention
- visually unappealing
- expensive to construct and maintain
Hard engineering - rip rap (rock armour)
Large rocks that reduce wave energy but allow water to flow through
+cost effective
- pose a hazard if climbed on
- rocks sourced from elsewhere
Hard engineering - revetments
Wooden or concrete ramps that help absorb wave energy
+ cost effective
- visually unappealing
- constant maintenance
Soft engineering - beach nourishment
sediment is taken from offshore sources to build up the existing beach
+ builds up beach naturally
+ cost effective
- needs constant maintenance
Soft engineering - cliff regrading and drainage
Reduces the angle of the cliff to help stabilise it. A steeper cliff would be more likely to collapse
+ cost effective
- may look unnatural
Soft engineering - dune stabilisation
Marram grass planted. The roots help bind the dunes protecting land behind it
+ cost effective and creates important wildlife habitat
- planting is time consuming
Soft engineering - marsh creation
Type of managed retreat allowing low lying areas to flood
+ creates important wildlife habitat
- farmers lose land and may need compensation
Cost - benefit analysis
Analysis carried out before any form of coastal management takes place. The expected cost of the construction, demolition, maintenance etc of a coastal management plan is the compared to the expected benefits of a scheme which may include value of land, homes and businesses that will be protected.
Integrated Coastal Zone Management (ICZM)
This is a method of sustainable coastline management.
- recognises importance of the coast for people’s livelihoods
- recognises that coastal management must be sustainable
- must involve all stakeholders
- recognises that sediment eroded in one location may form a protective beach elsewhere so looks at coastline holistically
Shoreline Management Plans
For each sediment cell in the UK, an SMP has been created to help with coastline management
Four options are considered for each stretch of the coastline :
Hold the line - defences are used to maintain the current position of the shoreline
Managed retreat - defiences and engineering techniques are used to allow the coastline to adavance inland and create its own natural defences
Advance the line - extending the coastline out to sea by encouraging build up of a wider beach
Do nothing/ no active intervention - letting nature take it’s course and allowing the sea to erode cliffs and defences to collapse
