Does the public expect too much of flood-risk management?
Following on from the summer floodings in the UK, Jean Venables OBE FREng, Chief Executive of the Association of Drainage Authorities, gives her views on the lessons learnt and what needs to be done to deal with future incidents of extreme weather
Jean Venables OBE FREng
Writing in the August sun, the media’s attention on the summer 2007 floods has already abated and has moved on to worry about Foot-and-Mouth Disease. However, many people continue to suffer from the effects of flooding of their homes or businesses. The current estimates of the cost of the direct damages amount to billions of pounds – excluding indirect and intangible effects – showing just how cost-effective it is to spend public money to manage flood risks. But will we be prepared to pay for it?
Public memory is exceedingly short in this country. We have a habit of reacting to severe weather events rather than planning for them in a structured way. Indeed, at the height of the drought of 2006, the Department for Environment Food and Rural Affairs (DEFRA) raided the budget for flood defences to offset losses in the Rural Payments Agency. The result was reduced maintenance of rivers and watercourses.
The question frequently asked after a flood is ‘who is to blame?’ We have to accept that financially, we cannot afford to protect ourselves from episodes when a month’s rainfall falls in three hours. So we must design for exceedance and build flood resilience into our property, especially our infrastructure. We must also use spatial planning to reduce the consequences of flooding.
Several investigations are under way into the floods and the lessons that should be learnt from them including the Environment Agency’s in-house response.
While it is important to learn the lessons from each flood, it is equally important to use those lessons. Indeed, it would be wise to dust off previous reports, including those for the floods of 1998 and 2000. These underlined the need to maintain our investment in flood-risk management. However, the Environment Agency has insufficient funds for the required maintenance and has to prioritise its expenditure.
A number of factors contributed to the inability of our rivers to carry away the heavy rainfall of this summer. In some places, lack of maintenance is likely to have exacerbated this particular flood. A further factor was the need to avoid disturbing nesting birds, which prevented the clearance of vegetation from channels between April and July. As a consequence, this spring’s prolific growth of vegetation reduced the ability of rivers and waterways to carry away the excessive rainwater. Indeed, in one instance weed growth in a channel reduced the capacity of a watercourse which meant that pumps at the end of a drainage network could not operate to their full capacity.
We have to rebalance the priorities between social, environmental and economic concerns to get a truly sustainable system that can operate to its full capacity to reduce flooding. The public finds it hard to understand that, while there is a legal duty to protect flora and fauna, there are only permissive powers to reduce the risks to people, property and infrastructure. While the environment is important, we must get a more appropriate balance to ensure a sustainable environment for us all.
Water-level management forms the basis of a civilised society – as we saw when water treatment works were out of action and a power station being narrowly saved from flooding. It allows those utilities upon which we now depend – water, power, communications and transport – to function effectively. It was clear from the public reaction that people expected better protection for these essential services.
We also need to address the balance between policy and practice. It has been estimated that recently increased administrative procedures have extended planning process for capital works from six up to 18 months, also increasing the cost.
Recent events also show that organisations must enable their staff to respond more quickly and to use their professional engineering judgement. Does it really make sense when a farmer offers to fill two empty irrigation reservoirs to alleviate the flow in the nearby swollen river, only to be told that he couldn’t because ‘he only had a winter abstraction licence’? This particular story may be apocryphal, but it chimes with many instances of a similar lack of lateral thinking.
The extreme weather of summer 2007 was typified by being extremely variable across the country. While areas of Cambridge experienced normal rainfall, a few miles north a month’s rainfall fell in three hours and there had been record rainfalls for two consecutive months. This shows that we cannot rollout national policies when there are such varying circumstances. For example, it was necessary to move more quickly from summer to winter operating levels to assist the drainage even though it was June.
Another frequently asked question is “is this flood an example of global warming?” Memories are short. Events of 1968 and other floods show that we have experienced this scale of event before. Only time will tell whether these events will become more frequent as the result of global warming. Samuel Pepys records in his diaries that the floods of 1663 “were the greatest tide that ever was remembered”. Indeed, the word ‘memory’ recurs in many reports on flooding.
What is changing is public expectation. There is now a growing belief that ‘someone,’ usually unspecified, should prevent these floods. This is simply not possible in all cases. The work of flood-risk management has been, and will continue to be, to reduce the risk. We will have to look at aspects of flood-risk management, including spatial planning, drainage, flood warning, flood defences and water-level management, as well as building resilience into properties and infrastructure.
Biography – Jean Venables OBE FREng Hon DSc
Jean Venables is Chief Executive of the Association of Drainage Authorities and Chairman of Crane Environmental which assists the construction industry to reduce the environmental impact of its projects and improve its sustainability performance, particularly by using the Civil Engineering Environmental Quality Assessment and Awards scheme, CEEQUAL. She is also a Visiting Professor at the University of Southampton and at Imperial College, and a Vice President of the Institution of Civil Engineers.
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