Coastal Management Strategies (Edexcel A Level Geography)

Structure 

How it works  

Advantages 

Disadvantages 

Groynes 

Structures built perpendicular (at right angles) to the shore.  Sediment is trapped as it is transported by longshore drift.  The beach builds up which absorbs wave energy 

• Not as expensive as other hard engineering structures 
• Builds up the beach which improves tourist potential

• Causes sediment starvation further along the coast 
• Can be unattractive 
• Need lots of maintenance to ensure sediment isn’t getting through any holes or cracks

Sea Walls 

Walls with a curved or stepped surface that absorb and reflect wave energy 

• Highly effective 
• Can have tourism benefits as walkways are created 

• Very expensive to build and maintain - £6000 per metre
• Are ugly and intrusive to the landscape 

Rip Rap/ Rock armour 

Large concrete or granite boulders at the foot of a cliff.  The spaces in between the boulders cause waves to bounce between many surfaces, reducing the energy of the wave

• Cheaper than sea walls 
• Used for recreation such as fishing 

• Dangerous when people are on them 
• Rocks from elsewhere are intrusive to local geology 

Revetments 

A sloped or ramp like structure that breaks up wave energy 

• Cost effective compared to other hard engineering strategies 

• Need lots of maintenance 
• Unnatural looking 
• Slopes are dangerous 

Offshore Breakwater 

Rock barrier a little out to sea from the shoreline.  This breaks the waves and dissipates their energy before they reach the coast.

• Effective 
• Away from the beach so does not disrupt tourist potential 

• Can create a navigation barrier in harbour areas 

Method 

How it works 

Advantages 

Disadvantages 

Beach nourishment/ replenishment 

Adding sand or shingle to a beach to widen it - this creates more surface area to absorb wave energy 

• Looks very natural 
• Bigger beaches are good for tourism 
• Relatively inexpensive 

• Material is constantly subject to erosion and longshore drift so lots of maintenance and monitoring is needed 
• Dredging the seabed can have impacts of local ecosystems 

Cliff Regrading and Drainage 

Reducing the angle of the cliff to stabilise the slope.  Drainage of water also stabilises the cliff against mass movement 

• Cost effective

• Can look unnatural as the cliff is unnaturally flatter 
• This effectively creating cliff retreat
• Dried out cliffs can collapse 

Dune stabilisation 

Planting species like Marram grass so that the roots bind the dunes.  The dunes absorb wave energy and protect the land behind. 

• Cheap and sustainable 
• Creates habitats for wildlife 
• Maintains a natural environment 

• People walk on the dunes and damage them 
• Planting is time consuming and it takes time for plant species to become established 

Marsh Creation 

This is a form of do-nothing or managed retreat.  Land is allowed to be flooded by the sea and then left to become a salt marsh.  This absorbs wave energy and also creates a buffer to rising sea level and projects higher value land. 

• A cheap option 
• Creates important and unique wildlife habitats 

• Agricultural land is lost which creates a need for compensation