The UK’s extensive coastline and the tendency for economic centres to develop in low-lying areas near to the sea means the UK is vulnerable to increases in sea level caused by climate change.
The UK Climate Change Risk Assessment Evidence Report 2017 concludes that a maximum increase in sea level of around 80cm is possible by 2100. In some areas, this means that flooding expected to be seen on average once a century could happen every few years.
Source: Newcastle University
Although over half of this rise will be experienced in the latter part of the 21st century, funding and engineering constraints mean that planning for adaptation in cities has to begin now, and by 2040, many of the interfaces between our cities and their waterfronts will have undergone substantial change.
In cities like London, Portsmouth and Hull, substantial flood defence solutions, such as the Thames Barrier, have already been developed to combat a present-day risk of flooding to existing communities. Adaptation works to prepare these defences for future change are already underway. The 'Thames Estuary 2100' programme, for example, will ensure the current high level of flood protection provided to our capital city is maintained into the 22nd century, but will involve substantial increases in height of the walls and banks that flank the River Thames. By meeting these requirements through the redevelopment of riverside sites over the next 20 years, an opportunity exists to reinvigorate riverside spaces, and provide better access for those working or travelling by the river. This will require careful thought by those investing in and developing riverside property.
In other cities such as Bristol and Southampton, existing flood defences are piecemeal and require significant investment that will severely stretch limited public budgets if it is to keep pace with the rising sea. In Bristol, for example, whilst short-term options exist to raise the height of the city’s harbour walls, this would fundamentally alter the interaction between the city and the waterfront, where shops, bars, restaurants and other amenities have clustered to create a thriving waterside destination.
In the longer-term, a substantial strategic solution will be required with funding requirements running into many millions of pounds. As the sea continues to rise, so does the likelihood that government investment alone will not be sufficient if other communities are to also avoid a significant increase in flood risk.
With fundamental environmental challenges like this on the horizon and significant variability in how these will be met across UK cities, it is imperative that investment decisions are made with a view to how climate change will affect future performance.