A changing coastline – the impacts and how we can adapt
Featured image: Storm surge damage by Evelyn Simak [CC BY-SA 2.0]
Factors influencing coastal change
The natural process of longshore drift alters the shape of coastlines by removing material (erosion) from beaches and coastlines and depositing it elsewhere (accretion). Due to climate change, changes in weather patterns could cause an increase in wet and stormy weather and also higher sea levels. Larger and more frequent storm surges can speed up coastal erosion and increase the risk of coastal flooding.
Land reclaimed from the sea enables development closer to the coast. Sea walls and revetments put up to protect the reclaimed land slows coastal erosion and therefore stop natural processes.
Managed realignment schemes set back flood defences further inland creating inter-tidal habitats in the form of mudflats and salt marshes. These coastal marshes help to dissipate wave energy and protect against coastal flooding and erosion.
Sand dunes act as a natural sea defence against coastal flooding and erosion but can become damaged by storms and human activity. Without sand dunes, the sea is able to advance rapidly and reclaim low lying land. Seaside towns have been developed over many years to create shops, hotels, piers and roads on land that was once intertidal.
Schemes that involve mimicking natural methods and measures to manage flood risk, such as beach nourishment, replace material that has been lost to the sea or wind and recharge the area with new material.
What does this mean for coastal communities?
Increases in coastal flooding
Rising sea levels as a result of climate change will mean that low lying coastal development will experience more flooding. Over time, this can have a negative impact on the mental health of residents and business owners.
Destruction to homes, businesses and farmland
Accelerated coastal erosion and more frequent coastal flooding caused by storms and higher sea levels will mean that coastal settlements are at risk of being destroyed and even falling into the sea. Funding for coastal schemes to protect against flooding and erosion is based on several factors. Therefore, it is not always economically viable to protect some coastal communities with extra defences.
With greater risk of some coastal settlements being inundated by the sea, it may be inevitable that you have to relocate to a new area. Households and businesses will have an uncertain future.
This is the case in Fairbourne, Wales, where it is no longer economically viable to protect the village. Eventually, the land will be returned to the sea and residents will be moved inland from 2045.
Loss of habitat and biodiversity
Mudflats and salt marshes that form on inter-tidal land are host to many habitats and species. By building on this land, many habitats and whole marine ecosystems can be lost.
Lack of investment
Coastal areas which are frequently flooded and show evidence of significant erosion may be more likely to deter investment and less likely to attract new businesses into the area.
Due to the unpredictability of climate change, coastal flooding and erosion, people and businesses owners may be less likely to relocate to an at risk area, with fear of flooding, abandonment and an uncertain future. Changes to the coastline may mean that recreational spaces and facilities are lost.
Adapting to coastal change
Adapting to a changing coastline is key to ensuring the impacts of climate change on people’s lives, towns and coastal areas are minimised. By planning ahead and putting provisions in place now where possible, people can adapt to living in a changing environment.
Creating smarter, adaptive buildings and infrastructure
New developments could incorporate property flood resilience measures or be adaptable to the effects of future climate change, for example, by building garages at the base of a house and living space above.
Work with natural processes
Encouraging sand dunes and salt marshes to grow and develop can provide a natural defence against coastal flooding and erosion. They can reduce wave energy before they reach the shore.
Creating a community resilience plan
Community resilience plans enable communities to be more prepared, efficient at responding and able to recover more quickly from disruption. Community resilience plans can be extremely useful in a flood for highlighting who may be vulnerable and the contact details of residents with useful skills or emergency evacuation centres.
Expand building setbacks – allow beaches and marshland to migrate
Managed realignment schemes allow coastal land to be naturally flooded and reclaimed by the sea. This reduces the financial costs of maintaining defences and encourages natural habitat.
Do your bit to reduce the impacts of climate change
By actively taking steps to reduce our carbon footprint, we can reduce the impact we have on the environment. Collectively, we could slow down effects of future climate change, such as rising sea levels.
Repair existing, old and damaged infrastructure
Over time, existing flood defence measures like sea walls become damaged due to wave power and subsequent erosion at their base. Rising seas may also make them ineffective. As a result, they may not be able to suitably protect against the sea level which were they designed for at the time of their construction. Therefore, repairing these existing structures and putting new schemes in place where necessary, enables essential coastal development to remain protected. Alternatively, old and damaged structures can be removed to let the land be reclaimed.
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Sources used: Living with a Changing Coast: Coastal change engagement toolkit – A step by step guide.