The Living World
21 Topics | 21 Quizzes

Managing Coastal Landscapes

Coastal erosion is a serious challenge that affects coastlines around the world, posing threats to ecosystems, infrastructure, and local communities.

Several strategies have been developed to manage and mitigate these impacts, which fall broadly into two categories:

  • Hard engineering
  • Soft engineering

Each approach comes with its own set of benefits and drawbacks, so they are selected based on the specific circumstances of each coastal region.

Hard Engineering

Hard engineering is the use of physical structures to manage coastal erosion and mitigate the impacts of waves. These measures offer immediate protection.

Sea Walls

Sea walls are concrete or rock barriers that stand tall against the relentless force of waves. They provide a robust defence for coastal areas. 

Here are some advantages of building sea walls:

  • Strong wave reflection, preventing erosion and reducing flood risk.
  • Immediate protection for properties and infrastructure.

However, sea walls also have some disadvantages:

  • Intense wave reflection can lead to increased erosion further down the coast, which can impact other communities
  • High construction and maintenance costs.
  • They changes natural sediment transport, which can result in beach loss and affect local wildlife.

Example of sea walls in the UK: The concrete sea walls along most of Swanage Beach in Dorset protect the cliffs from erosion but create a strong backwash that removes sediment from the beach.

Groynes

Groynes are wooden or stone barriers that extend perpendicular to the coastline, interrupting longshore drift and trapping sediment.

Longshore drift is the movement of sand and stones along a coastline by wave action, which can lead to more erosion. By trapping sediment, groynes counteract this process.

They offer several advantages:

  • Increased beach width, providing a buffer against erosion. Beach width refers to the distance between the water’s edge and the end of the beach.
  • More recreational opportunities with larger, more stable beaches, benefiting local communities and tourists.

However, groynes also present a few disadvantages:

  • When the flow of sediment is disrupted, it can result in the narrowing of beaches and increased erosion in the surrounding areas.
  • Higher maintenance requirements to counteract sediment accumulation behind the groynes. This can be a potential burden on local authorities.

Example in the UK: The timber groynes installed on Swanage Beach have successfully reduced beach erosion but have also caused narrowing and increased erosion further along the coast.

Soft Engineering

Soft engineering uses natural processes and techniques to manage coastal erosion and maintain the delicate balance of coastal ecosystems.

This approach often works harmoniously with the interests of local communities. Also, it is much less disruptive to natural processes, compared to hard engineering techniques.

Beach Nourishment

Beach nourishment involves adding sediments, such as sand and shingle, to replenish eroded beaches. It offers many advantages:

  • Increased beach width, which protects the coast from wave impact.
  • Improved habitat for coastal flora and fauna, which can boost local biodiversity.
  • Recreational benefits with expanded beach areas.

However, beach nourishment also has a few disadvantages:

  • There are high costs associated with acquiring and placing sediment on the beach.
  • Regular maintenance and replenishment are required due to natural erosion processes.

Example in the UK: The replenishment of sand and shingle on Swanage Beach from dredged material in Poole Harbour widened the beach and reduced erosion. This provided increased protection to properties and cliffs.

Managed Retreat

In certain cases, allowing coastal areas to retreat naturally may be more practical. This method, known as managed retreat, accommodates erosion and gives space for the sea. It offers some unique advantages:

  • Cost-effective and environmentally friendly, working in harmony with natural coastal processes.
  • Allows for the restoration of natural habitats and the creation of dynamic coastal ecosystems.

However, managed retreat also has a few disadvantages:

  • The potential loss of properties and infrastructure in the affected areas.
  • Relocation challenges for affected communities.

Example in the UK: The Medmerry Managed Realignment Scheme in West Sussex involved moving sea defences inland to create new intertidal habitats, allowing the coast to adapt naturally while reducing flood risk.

You’ve used 10 of your 10 free revision notes for the month

Sign up to get unlimited access to revision notes, quizzes, audio lessons and more

Sign up