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Feeling drained

Analysis - As property owners in the north of England mop up after last week's floods, John McKenna assesses the impact of their plight on future development.

LAST WEEK'S flooding hit 27,000 homes and 5,000 businesses and is likely to generate a total of £1bn in insurance claims, according to the Association of British Insurers (ABI). This represents 71% of the average annual flood damage for England and Wales, and with many ooded households uninsured, the true cost of the devastation is likely to be much higher.

It is thought that a large number of the affected properties had been built in flood-prone areas since the Second World War, although the Environment Agency is unable to provide exact details.

But in the context of the recent devastation, the question inevitably arises as to whether it makes sense to build on flood plains. NCE readers clearly think not: this week's uk online poll asked: 'Should developers be allowed to build on flood plains?' The majority, 80%, answered no.

Sadly, Gordon Brown is (probably) not a regular visitor to nceplus. co. uk and the new prime minister is unlikely to be swayed by engineering opinion alone. He has made building more houses one of his top priorities, setting a target of 200,000 new homes per year.

To achieve this goal, a large swathe of land, mostly in south east England, has been identi d by the government for development. But according to the Agency, 80% of identied sites are at risk of ood, and 10% of those houses to be built on flood plains are at serious risk.

Of course, England desperately needs more housing, and with the development of green belt land politically off-limits, the development of large oodprone areas such as the Thames Gateway will continue unabated, despite recent events.

'We live on an island and the majority of the country is a flood risk area, ' says a Department for Communities & Local Government spokesman. The department is responsible for implementing the prime minister's housing ambitions.

'We need to build new homes and it's a case of managing risk rather than not building.'

This method of managing risk, as set out in Planning Policy Statement 25, requires local planning authorities to approve developments in areas least likely to flood.

Despite this guidance, developments can go ahead on oodprone sites if no other suitable sites can be found and they meet the Exception Test: that they contribute to the government's concept of sustainable communities; ideally, they are built on brownfield land and they are safe from ooding without increasing the flood risk to surrounding areas.

But what constitutes being safe from ooding is unlikely to be traditional protection from ood defences.

On Monday, environment secretary Hilary Benn confi med that the Department for Environment, Food & Rural Affairs (DEFRA) would receive increased funding for flood-risk management and defences in the autumn's Comprehensive Spending Review, rising from this year's £600M to £800M in 2010/11.

But it is likely that only a small proportion of the increased funds will go to the Agency to be spent on defences. Agency chief executive Barbara Young told MPs last week that it would take an extra £150M per year, on top of her current £500M budget, just to clear the backlog of repairs and upgrade work to flood defences considered to be in poor condition.

With the Agency predicting that, due to climate change, it will require as much as £75bn of new engineering works by 2080 to keep flood damage to £2bn per year, it is unsurprising that the government is seeking cheaper solutions to flooding than the construction of traditional defences.

Two pilot schemes being run by DEFRA give an indication of where a large part of the extra money will go, both accepting that fl oding will occur but looking at the best ways of coping with it.

The first plan consists of 15 pilot schemes looking at closer working between the various stakeholders in charge of urban drainage: the highway authority for road drainage, the water companies for sewer drainage, and the Agency. The schemes aim to improve planning processes to channel flood water away from properties using roads and open spaces.

The second scheme looks at making properties more resilient to fl ooding by making alterations to the buildings themselves. This includes installing fl ood guards in front of doors and using tiled concrete floors, resilient plaster, raised electrics and appliances on plinths. So far tenants of houses in the scheme have merely had to mop up their floors to return to normal.

Both of these schemes could have made a difference during last week's floods. Young told MPs at the Public Accounts Committee hearing in the House of Commons last week that none of the recent flooding had been due to breached flood defences. It was rather the result of record-breaking levels of rainfall overtopping river defences and overwhelming surface water drainage.

'Our primary areas of focus historically have been the sea and rivers. But at the moment a lot of flooding is happening in areas remote from the rivers and seas. We want 25-year drainage plans. There need to be longterm drainage plans to allow water companies and developers to plan drainage needs for an area.' It remains to be seen whether such long-term plans become a reality. Flooding consultant and ICE vice-president Jean Venables said new developments could also be helped if the government introduced regulations on the maintenance of Sustainable Urban Drainage Systems (SUDS). These use attenuation and retention to slow the rate at which water enters drainage systems, and encourage it to permeate into the ground.

But deciding whether it should be the water companies, developers or property owners who adopt these remains a thorny issue because no-one wants to assume the long-term responsibility for them.

It is an issue which is giving consulting engineers, developers and water companies a headache and pushing up the cost of SUDS.

The solution would be for the government to make maintaining the systems a statutory obligation for one body, says Venables. Cheap and simple and requiring minimal public spend, such a move would fit perfectly with the government's current approach to flood management.

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