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How to turn the tide?

Autumn 2000 was one of the wettest on record, leading to repeated flooding across the country. The Environment Agency launched an investigation to look at management of the situation and at how such destruction can be avoided in the future. Nina Lovelace

Railtrack warned last week that £250M needs to be spent on repairs to infrastructure damaged during acute flooding in autumn last year. Across the country embankments need to be rebuilt and ballast replaced after material was washed away in some of the highest and most prolonged flooding seen in 40 years. County surveyors estimate the floods have added £100M to an existing £5bn road repair bill (NCE 29 March).

However, it comes as no surprise to the Environment Agency, which warns of soaring repair costs in its report, 'Lessons learned: Autumn 2000 floods'.

Presented to Government last month to explain the Agency's management of the floods, the report puts the damage to homeowners alone in the region of £1bn. And as still more damage assessments pour in, costs are rising.

Some 1,000 properties were inundated across the country in 700 different areas. Many were swamped with sewage as storm water drains backed up. More than 11,000 people were evacuated and many still live in temporary accommodation.

Of the 700 flood incidents, 28% were caused by the failure of existing Environment Agencyowned flood defences on main rivers. Defences failed because they were either overtopped or were outflanked - water flowed around them. Others collapsed under the strain.

Meanwhile, 32% of flood incidents were caused by flooding of ordinary watercourses falling within the jurisdiction of local authorities or individuals, or by inadequate surface water drainage.

However, 40% of flooding occurred in areas near main rivers previously considered a low flood risk, where there were no flood defences at all.

Experts agree that the extent of the flooding can be excused to some degree because conditions were exceptional. Even during 'normal' floods, defences are never 100% waterproof.

But what of the unquantifiable emotional cost wreaked by last year's floods, the report asks?

People are at least as interested in the Agency's efforts to manage the situation as they are in the devastation left when the flood waters receded. What lessons, people want to know, did the Agency learn from last year's experience and how will they be applied next time around?

The Environment Agency delivered a total of 1,437 flood warnings over the autumn floods, of which 190 were 'severe', alerting people that flooding was imminent. Warnings were given either by an automated telephone voice message system using sirens or vehicle mounted loudhailers, or in person by flood wardens.

However, it was only in areas classified as high risk that the warning infrastructure was in place. In north Wales only 400 warnings were given, leaving people in a further 1,500 'low risk' areas to face rising waters with no warning at all. The extent of flooding took everybody, including the Agency, by complete surprise.

In the light of last autumn's experience the Agency will re-evaluate some of its risk assessments, add new areas to its 'at high risk' list and invest in more rapid and extensive flood warning delivery.

In areas not covered by the Agency's flood warning network, the public was given information about advancing waters through local and national media. The Agency's Floodline telephone information service received 781,000 calls between October and December, compared to 100,000 during the previous 11 months.

But the Agency admits that it was swamped by the demand for information. 'At peak times during October and November as few as 30% of calls were being answered and handled successfully by call centre operatives, ' the report says.

In the field, meanwhile, as many as 3,500 Agency staff were working round the clock in some of the worst hit areas, managing defence fortification operations.

Despite being overstretched, their dedication and efforts were described as 'exemplary'. But inadequate training left some unsure of the best way to deal with potential pollution incidents resulting from the floods.

The Agency intends to provide generic guidance in future.

The Environment Agency concedes that managing one flood incident well does not reassure the homeowner, who hears repeated talk of climate change, sees the evidence of ever wetter winters, and lives in fear of the next inundation.

What needs to change?

The Agency has called for the Ministry of Agriculture Fisheries & Food (MAFF) to re-evaluate who is responsible for flood defences. Current allocation of responsibility leads to confusion as the Agency oversees only main rivers while local authorities look after the smaller watercourses. There are also numerous private watercourses and drainage systems for which there is no clear allocation of responsibility.

'Historic decisions that attribute responsibility for different watercourses have, in some locations, little relevance to the communities they now drain, ' says the report.

Taken nationally, there is too little control over maintenance and new build programmes. The chain of command in emergencies is unclear and weak. 'The complex assessment of who should resolve a problem is of no value to someone who needs help to deal with a flooding problem and does not know where to turn to for advice and support.'

The Agency also draws attention to the scant information held on the condition of the nation's flood defences. Prioritising funding is difficult.

Intelligence on defences should be gathered by the Agency through a detailed, government-funded survey, the report suggests. At the very least the Agency must have powers to demand information about defences from local authority or private owners. Information should be logged to deliver a comprehensive, standard, unified database and maintained and updated.

And the Agency urges improvement of surface water drainage. 'These floods demonstrated the extent to which flooding may be caused by inadequate surface water drains. . .

surface water drains are not designed to handle high-risk rainfall events.' New planning policy for development in flood plains, Planning Policy Guideline 25, is expected to promote more sustainable drainage design.

Any improvement in the way the Environment Agency responds to flooding calls for extra government funds. Local councils and the Agency receive around £200M/year each. But in a recent internal report, MAFF estimated an extra £100M was needed for maintenance of, upgrading or building new flood defences. It urges that future designs for defences should be flexible: 'The options appraisal should encourage the construction of flood defences that can easily be modified in response to the impacts of climate change, ' the report says.

Part of future funding should also be pinpointed at further improvements to flood warning systems, such as increasing the number of properties in flood risk areas that have automatic telephone message systems.

In its defence, the Agency adds that 280,000 properties were successfully protected by flood defences, and 37,000 protected by emergency measures such as the use of sandbags.

Flood warning and forecasting systems also proved very successful in the areas that they served.

And steps to reduce the risk of flooding can be made by everyone, including business and industry, it says. The report urges water and power utilities, Railtrack and the Highways Agency to carry out flood risk assessments and have contingency plans for their assets in flood risk areas.

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