New Noah's Arks
This article was first published in the September/October 2005 edition of Green Futures magazine - www.greenfutures.org.uk
Today’s buildings and communities need to face the floods,
says Entec’s Bill Finlinson.
Flooding in Boscastle, Carlisle, north Yorkshire… it shows no sign of
letting up. The headline figure is that about 1.2 million homes are ‘at
risk’ from inland flooding in the UK. But what does this mean to people
on the ground and how should planning authorities design communities to accommodate
this risk?
A lot of it is about changing mindsets and attitudes. Planning authorities are only just coming to terms with flood risk as a major determining factor in development location. As new regional spatial strategies and local development frameworks progressively replace the old local and county plans, planners need to be thinking about where development can be built, what kind is suitable, and how it should be constructed.
Property developers, for their part, need to be encouraged to look at flood mitigation as an opportunity, not an imposition. Many are reluctant to be ‘upfront’ about the potential flood risks on their site in case they discourage purchasers or invite problems with insurance.
However, insurers are becoming more informed about flood risk and the industry is actively encouraging adoption of flood management measures. A recent report by Entec for the Association of British Insurers on the government’s Growth Areas highlighted potential savings in flood damages of up to £50 million a year through proper planning, location and design of new development. These can be major selling points as well. Riverside sites are a golden opportunity to marry good waterfront landscaping with flood resilient design. By all means sell your property for that unique riverside view, but why not also display those attractive landscaped areas you have set aside in case of flooding, and show how your property has been built above the appropriate design level?
Local communities themselves need to be more aware of the risks of where they are living and given guidance as to what to do in an emergency. The National Flood Forum (NFF) was set up to share experiences and advice among communities that have suffered major flooding. Many of these communities have formed active local flood groups, but the NFF is now keen to get the message to those who have not yet been flooded or who might be in the future.
As a case in point, east London has some of the largest low-lying areas of intensive urban development in the country. As you might expect, it’s very well defended against flooding behind the Thames Barrier, and development has gone on apace. And therein lies the problem. Although the likelihood of water overtopping these tidal defences is extremely low, the consequences would be so severe. Because the ground in the Thames estuary is up to 5 metres below the crest of the structures we would see a rapid and widespread inundation of property if any failure of defences were to occur. Yet developers and residents come and go without any appreciation of the risk, as there are few people around with long enough memories to remember flooding before the defences were built.
There are plans afoot to develop a further 100,000 houses in the area by 2016, and the Thames Gateway London Partnership is giving much thought to how this can be planned sustainably. A study being carried out by Entec is considering where water would flow in the event of a breach of the defences or an extremely intense rainstorm. Mitigation measures are also being examined, including the use of embankments and canals to divert water away from existing housing into set-aside floodplains. These areas, often located alongside existing streams, can also double as ‘green’ amenity and recreation areas.
The challenge is to get local authorities and property developers thinking along these lines, and then to help residents appreciate just why their communities are being designed the way they are.
Bill Finlinson is an associate director with Entec
UK.
Entec UK, 0800 371733, www.entecuk.com
National Flood Forum, www.floodforum.org.uk
Making Communities Sustainable – managing flood risks in the Government’s
Growth Areas is available for download from www.abi.org.uk/housing
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