Storm Desmond: What are the solutions?

When storms – such as those we have seen recently in Cumbria – cause already existing flood defences to be overtopped, Professor David Balmforth asks, what is the solution?

The scene in Cockermouth, Cumbria in December 2015, only six years after the town was devastated by serious floods. Image: morebyless, via Flickr
The scene in Cockermouth, Cumbria in December 2015, only six years after the town was devastated by serious floods. Image: morebyless, via Flickr

Do we simply build higher defences? While this might seem to many the obvious choice, it is likely that even higher flood defence walls may not be welcome in most communities. Such walls and embankments can visually and physically divide a community, cutting it off from important vistas that help to create a good sense of space. Already we see the design of flood defence walls softened with glass panels to make them less visible. Do we really want to add an extra metre to these facilities?

But if not, what else might be done to stop a repeat of 2015’s floods?

Even with well-designed defences, we must open our minds to other possibilities. We must explore options that help communities to become more resilient to flooding and thus avoid much of the hardship seen after the recent events.

The concept of building resilience to flooding is by no means new. There are plenty of examples of success. Yet, here in the UK we have not so far succeeded in supporting communities to become resilient to flooding in a structured and strategic way.

How do we help communities become more resilient?

There are three obvious areas where we might do better.

  1. Since the 2007 floods, the Met Office and the Environment Agency have made great strides in forecasting and issuing warnings of severe weather. Such forecasts are not always translated well into the risk that communities face from flooding, nor communicated well to individuals. Better local support could be given to those at risk to help them prepare. This is particularly important for the more vulnerable. And it is a particular challenge in communities ‘protected’ by flood defences since they understandably believe that they are no longer at risk of flooding.
  2. There are plenty of examples to demonstrate how the fabric of buildings can be changed to make them more resistant to floodwater:
    • Fitting water sealing doors and vents can help to keep flood water out of buildings
    • The use of concrete and cement based materials in floors and walls, rather than timber and gypsum products, will not only avoid damage to the fabric, it will help prevent flooded buildings becoming water-logged
    • When buildings are adapted in this way they can be brought back into use after a flood in a matter of hours rather than needing months to dry out
    • New homes and commercial premises should all benefit from such measures, even when not in flood risk areas (all buildings are to some extent at risk of flooding)
    • This should be written into the Building Regulations. All new developments in flood risk areas should be built with thresholds a minimum of 1m above the level of surrounding ground or known maximum flood level, whichever is the greater
    • Similar measures can be implemented for infrastructure. There are many examples of key infrastructure components being raised above flood levels or protected with local flood walls. This should be standard practice in all flood risk areas, including those areas ‘protected’ by flood defences. This will help to prevent the cascading failure of infrastructure during flood event
  3. Modern modelling tools can be used to help us to better understand how flood water progresses through communities. This in turn can help us to see how flood water might be ‘actively managed’, for example, by adapting roads and pathways to act as flood channels to keep water away from property and infrastructure. Such tools can also help to inform emergency response.

Despite the lessons learnt in responding to recent floods, there are still many gaps in helping communities to recover from floods. This is particularly true with the longer term impacts, such as the effects on health.

Is Government doing enough?

Strong leadership on flood risk management is important. Strategically we might serve society better if we were to see flood risk management as consisting of two parallel strands, one that seeks to protect communities and infrastructure from flooding through the provision and maintenance of appropriate flood defences, and the other to build effective flood resilience into communities, whether or not they benefit from defence works.

The challenge for Government is that the responsibility for delivering the resilience measures set out above is split between different departments, principally the Cabinet Office, Communities and Local Government, and Defra.

We need to see a much more joined-up approach to ensure that the flood resilience strand of flood risk management receives immediate attention and appropriate long term investment.

The Government has promised an investigation into the recent events. We do not need another extensive review of flood risk management in the England (we have yet to implement all the important recommendations of the 2008 Pitt Review).

But we do need to better understand and communicate what we can expect from our investment in flood defences in the future.

The promise of Government funds to help home owners and businesses affected by the recent floods to improve the resilience of their property is welcome. It would be a very positive step forward to see property that has suffered from the recent floods reinstated in a flood resilient form rather than simply putting back what was there before.

Hopefully the Government will now look at how such support could be more widely implemented so that households and businesses do not have to wait until after they have flooded before they can make their premises more resilient to floods.

At the very least we could ensure that all new development is built to a flood resilient standard.

David discusses the Cumbria flooding crisis on the BBC News

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About the author

ICE President 2014/15, David Balmforth
Professor David Balmforth

Professor David Balmforth is a national flooding expert, currently an Executive Technical Director with international consultants MWH. His work covers all aspects of urban flood control, pollution management and climate change adaptation in the wastewater sector, and he is currently advising on major flood alleviation projects in London and Singapore.

An independent advisor to the UK Water Regulator (OFWAT) and the Department for Environment, Food and Rural Affairs, and to Thames Water and the Greater London Authority, David is a visiting professor in the Department of Civil and Environmental Engineering at Imperial College, London.

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