Coastal Protection Soft Engineering

Coastal protection refers to measures taken to prevent or reduce damage from coastal hazards, such as erosion, flooding, and storm surges. These measures can include natural solutions, such as beach nourishment and dune restoration, as well as man-made structures, such as seawalls, breakwaters, and jetties – which we discussed in our article on hard engineering.

The specific approach used will depend on the location, the type of hazard, and the goals of the project. The main aim is to protect coastal areas and infrastructure, such as buildings, roads, and critical facilities, as well as preserving coastal ecosystems and habitats.

In this article, we’ll focus specifically on soft engineering, which is a type of coastal management approach that utilizes natural processes and materials to protect and stabilize coastal areas. This method of coastal protection differs from traditional hard engineering techniques in that techniques such as beach nourishment, dune restoration, and the creation of wetlands aim to mimic natural processes and work with the environment to achieve a sustainable outcome, rather than using man-made interventions. This approach is often considered to be more environmentally friendly and cost-effective in the long-term.

Distinction Between Hard and Soft Engineering

Hard Engineering

Hard engineering refers to the use of man-made structures and technology to control coastal processes and protect coastal areas from erosion and flooding. This approach often involves the construction of physical barriers such as seawalls, breakwaters, and jetties to protect against the sea.

It also includes the building of groynes, revetments and other structures to hold back the sea and prevent erosion. It’s typically considered as a more traditional and mechanical approach as it involves the use of concrete and other hard materials in the construction of these structures. Hard engineering is mainly used to protect coastal areas and infrastructure such as buildings, roads, and critical facilities.

An example of hard engineering — A sea wall is an example of hard engineering. This sea wall is at Pett Level Beach, East Sussex

Soft Engineering

By comparison, soft engineering techniques involve working with natural processes and ecosystems to achieve sustainable coastal protection. This approach includes methods such as beach nourishment, dune restoration, and the creation of wetlands, and is often considered to be more environmentally friendly and cost-effective in the long-term.

Soft engineering also includes the use of natural materials such as sand, vegetation and other natural materials to protect coastal areas from erosion and flooding.

coastal protection soft engineering example: dune restoration — An example of soft engineering in the form of dune restoration at a beach in St Annes, UK

Beach sustenance

This technique is also known as beach nourishment, beach renourishment, or beach replenishment. It is a coastal management technique that involves the addition of sand or other sediment to a beach to restore or enhance its width and/or elevation. This is typically done to counteract the effects of erosion caused by natural processes such as wave action, tides, and storms.

Beach nourishment can be done through the use of dredged material or by importing sand from other areas. The added sand can be used to create or widen a beach, to rebuild dunes, and to protect coastal infrastructure such as buildings, roads, and critical facilities. Beach nourishment can also be done to improve recreational areas, as well as to protect coastal ecosystems and habitats. Beach nourishment is a form of soft engineering, because it uses natural materials and works with natural processes to achieve coastal protection.

An example of beach sustenance in Barcelona to replenish sand lost through wave action

Dune Restoration

Dune restoration is a type of coastal management technique that involves the rebuilding or enhancement of natural sand dunes. Dunes are important coastal features that provide valuable ecosystem services such as coastal protection, wildlife habitat, and recreational opportunities. Dune restoration can be done through the use of beach nourishment, where sediment is added to the beach to rebuild or enhance dunes, or through the planting of vegetation, such as beach grass, which helps to stabilize dunes and prevent erosion.

Dune restoration can also include the removal of non-native species and the protection of existing dunes from human activities such as off-road vehicle use. The goal of dune restoration is to protect coastal areas and infrastructure such as buildings, roads, and critical facilities, as well as preserving coastal ecosystems and habitats. Dune restoration is a form of soft engineering, because it uses natural materials and works with natural processes to achieve coastal protection.

An example of dune restoration using the planting of grasses at a beach in St Andrews, UK

Overseen retreat (coastal realignment)

Coastal realignment is a type of coastal management technique that involves the relocation or reshaping of coastal infrastructure and development away from areas that are at high risk of flooding and erosion, and towards areas that are more stable. This can include the relocation of buildings, roads, and other infrastructure, as well as the creation of new wetlands and other natural coastal features.

Coastal realignment is often used as an alternative to hard engineering techniques such as seawalls and levees, which can be costly and have negative impacts on coastal ecosystems and habitats. By working with natural processes rather than against them, coastal realignment aims to achieve long-term coastal protection while also preserving or enhancing coastal ecosystems and habitats. Coastal realignment is a form of soft engineering, because it uses natural materials and works with natural processes to achieve coastal protection. It’s also known as managed retreat which means to move back from high risk areas rather than trying to hold the line.

An example of coastal realignment on the beaches of Freiston Shore. The land has been given over to marshes and saltpans.

Hill Regeneration

Hill regeneration in soft engineering refers to the practice of restoring and preserving natural hill ecosystems through the use of natural materials and methods. This can include techniques such as reforestation, erosion control, and the reintroduction of native plant and animal species. The goal of hill regeneration is to improve the overall health and stability of the hill ecosystem, which in turn can provide benefits such as water catchment, soil conservation, and wildlife habitat.

Hill regeneration is a form of soft engineering because it uses natural materials and methods to achieve the desired outcome, rather than relying on man-made structures or technology. The process usually starts with an assessment of the current state of the hill ecosystem, followed by the implementation of a management plan that includes activities such as vegetation planting, soil conservation, and erosion control. This can be done by a variety of techniques such as contour ploughing, terracing, and use of vegetation cover. The end result is a stable and sustainable hill ecosystem that is better able to withstand the impacts of natural processes such as erosion, landslides, and other hazards.

Seashore Reprofiling

Seashore reprofiling refers to the practice of reshaping the beach and nearshore area to improve coastal protection and enhance recreational opportunities. This can include the reshaping of the beach profile, the reshaping of the nearshore area, and the construction of beach amenities such as walkways and facilities. The aim is to improve coastal protection and make the beach more accessible and appealing to visitors.

Seashore reprofiling is a form of soft engineering because it uses natural materials and methods to achieve the desired outcome, rather than relying on man-made structures or technology. The process usually starts with an assessment of the current state of the beach, followed by the implementation of a management plan that includes activities such as beach nourishment, dune restoration, and the reshaping of the beach and nearshore area.

This can be done by a variety of techniques such as dredging, use of heavy equipment, and beach scraping. The end result is a more stable and sustainable beach ecosystem that is better able to withstand the impacts of natural processes such as erosion, tides, and storms and also provides more recreational opportunities.

An example of seashore reprofiling in action through sea defences at Borth, Wales

Summary

In summary, when it comes to coastal protection, there are two main approaches: hard engineering and soft engineering. Hard engineering involves the use of man-made structures and technology to control coastal processes and protect coastal areas from erosion and flooding. Examples of hard engineering include seawalls, breakwaters, and jetties. While hard engineering can be effective, it is often costly and can have negative impacts on coastal ecosystems and habitats. Soft engineering, on the other hand, utilizes natural processes and materials to protect and stabilize coastal areas. Examples of soft engineering include beach nourishment, dune restoration, and the creation of wetlands. Soft engineering is generally considered to be more environmentally friendly and cost-effective in the long-term, and it also provides benefits to coastal ecosystems and habitats.

Frequently Asked Questions

What is coastal protection soft engineering?

Coastal protection soft engineering refers to the use of natural and nature-based methods to manage coastal erosion and reduce the impact of coastal hazards. It involves approaches that work with natural processes, such as beach nourishment, dune restoration, and salt marsh creation.

How does beach nourishment help with coastal protection?

Beach nourishment involves adding sand or sediment to eroded or depleted beaches. It helps widen the beach and create a buffer zone against wave energy, reducing the potential for erosion and providing protection to coastal communities.

What are the advantages of dune restoration for coastal protection?

Dune restoration involves rebuilding and enhancing natural sand dunes along the coastline. Dunes act as natural barriers, absorbing wave energy and protecting inland areas from erosion and storm surges. They also provide habitats for various plants and animals.

How does salt marsh creation contribute to coastal protection?

Salt marsh creation involves the restoration or establishment of coastal wetlands consisting of salt-tolerant plants. Salt marshes act as natural buffers, attenuating wave energy, reducing erosion, and providing important habitat for wildlife. They also improve water quality and promote biodiversity.

What are the environmental benefits of coastal protection soft engineering?

Coastal protection soft engineering methods have several environmental benefits, such as preserving natural coastal features, promoting biodiversity, maintaining sediment transport processes, enhancing habitats for marine and coastal species, and supporting sustainable tourism and recreation.

References

Considering coastal management, explain the difference between hard engineering and soft engineering, highlighting examples alongside advantages and disadvantages. (n.d.). Retrieved from
DK Science: Coasts. (n.d.). Retrieved from FactMonster: https://www.factmonster.com/dk/encyclopedia/science/coasts
Managed realignment: A viable long-term coastal management strategy? (n.d.). Retrieved from ResearchGate: https://www.researchgate.net/figure/Examples-of-soft-engineering-schemes-a-beach-nourishment-in-Palm-Beach-Florida-USA_fig4_261508267
Soft Engineering. (n.d.). Retrieved from Tutor2U: https://www.tutor2u.net/geography/reference/soft-engineering
Soft Engineering. (n.d.). Retrieved from GetRevising: https://getrevising.co.uk/grids/soft_engineering_2

What is Coastal Protection?