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Managing the flood challenge

With new legislation and regulations in place, flood management will impact on projects in all sectors. Jo Stimpson finds out where the priorities are.

Six months on from last November’s devastating floods, Cumbria County Council issued a review of its flood recovery progress.

It stated that gains had been made in some areas - people back in their homes, temporary road and foot bridges built - but that there were still many problems left unsolved. Nine bridges were still unrepaired, said the council, and vulnerability to flooding was still keenly felt by many residents (NCE 27 May 2010).

In many ways, the situation reflects that in the country as a whole. The UK continues to learn from the lessons of the 2007 floods, and many aspects of the UK’s flood management have improved - but plenty more are still being worked out.

Three years on from the disaster that led Sir Michael Pitt to write his seminal review of the country’s vulnerability to flooding, and with the Flood and Water Management Act finally given royal assent in April, NCE spoke to flooding experts to find out how far there is still to go towards achieving flood resilience.

“We’ve come a long way,” says Environment Agency acting director of flood risk management David Rooke.

“The evidence for that is the really good response in Cumbria last November.” Indeed, in the current spending period the Environment Agency expects to surpass its goal of protecting 145,000 properties between 2008-2011, projecting that it can defend 18,000 more by next March.

Better prepared

MWH senior principal engineer and surface water management expert Chris Digman says that if the 2007 floods were repeated this year, the country would be much better equipped than it was three years ago. He says: “I think we would see an even better response from all the various authorities, and I think we would see a great improvement in [the resilience of] the actual critical infrastructure.”

The Environment Agency and Met Office’s joint flood forecasting centre is a great improvement, says Digman. Indeed, in Cumbria in 2009, 900,000 homes and businesses were warned directly before the floods. In January this year the Agency also launched a new flood warning service specifically for owners and operators of infrastructure.

“The challenge is still to protect as many people but by using less resources or by bringing in resources from elsewhere”
David Rooke, Environment Agency

And as for the areas that still need improvement? The resilience of critical infrastructure is a major concern for many. “It has to be high on people’s agendas,” says Digman. Association of Drainage Authorities chief executive and former ICE president Jean Venables agrees. Property and the emotional impact of flooding receive the most attention, she says, but roads, railways and buried utilities are vital for the continuity of the travel and electricity networks without which flood recovery becomes extremely difficult.

Surface water management is another area for improvement, says Digman. “Although we’ve made some great strides, have we moved forward quick enough to actually manage surface water in a really extreme event?” he asks. It is vital that local authorities undertake Surface Water Management Plans (SWMP), understand their priorities and then take action, he says.

Legislation means work

Complying with the new Flood and Water Management Act will provide plenty of work in the near future.
The Environment Agency is already discussing the national flood and coastal erosion risk management strategy that the Act requires it to develop, maintain, apply and monitor.

Meanwhile, unitary authorities or county councils must take on the role of lead local flood authority for their areas, and establish a local flood risk management strategy to sit underneath the national one.

Venables says some local authorities are likely to meet challenges in securing resources and in perfecting the wording of their strategies. “Many of them currently don’t have the expertise at all, or the funding stream.” She says it is also crucial that the national strategy leaves scope for the individuality of local strategies. “If it’s too prescriptive it will prevent the best solutions. That’s worrying to me.”

The other critical aspect of the Act is its ruling on Sustainable Urban Drainage Systems (SUDS). “Construction work which has drainage implications may not be commenced unless a drainage system for the work has been approved by the approving body,” reads the Act - the approving body being the local unitary or county council. This tenet means the government must now publish national SUDS standards, and councils must set up their approving bodies.

Moreover, every new project will have to be considered to determine whether it will affect rainwater absorption. If it will, sustainable drainage will have to be designed in and will have to reach approval. Interestingly, these rules apply even to very small works - they cover “anything that covers land (such as a patio or other surface)”, says the Act.

“Without surface water management plans it will be impossible to effectively address all flood risk”
Chris Wotherspoon, Grontmij

But in spite of the real changes to be brought in when the Act comes into force, it does not address all of the 15 key recommendations made by Pitt. It remains to be seen whether more of Pitt’s conclusions will be addressed in a future bill. In February NCE learned that Defra was planning to introduce a water bill to address issues left out of the Flood and Water Management Act (NCE 26 February 2010) - but all bets are off following the general election. Digman says he will be interested to see whether the new government will try to make changes to the Act, or bring forward further legislation.

Alongside the Act, the Flood Risk Regulations - which transpose into UK law the European Union (EU) Floods Directive - oblige local authorities to undertake preliminary flood risk assessments this year, in preparation for flood risk management plans to be published by the end of 2015 (News this week).

Hot topics

With that said, what do flooding experts feel will be the hot topics going forward? Digman says surface water management awareness and projects will continue to grow, not only because of their importance in the Flood and Water Management Act but also due to their secondary benefits in taking pressure off existing drains and combined sewers, and improving water quality.

By managing surface water above ground using SUDS and other measures, he says, drain capacity is freed up, reducing the need to build bigger assets and drains to cope. And since drains and combined sewers are under less pressure, there are fewer overflows into water courses and a lower chance of water quality degradation. “Other flooding agendas will drive the need for surface water management measures,” he says.

What is more, Digman says surface water management measures can make a real and effective contribution to managing extreme flood events - and to raising awareness of flooding. Above ground measures are much more visible than underground drains. The theory is that if it water storage is more visible to the public, they will notice when it is filling up and will be more likely to take early action to defend their homes against floods.

Grontmij technical director and flooding specialist Chris Wotherspoon goes further and says these projects will be essential to offering sufficient flood protection. “Surface water management plans will play a fundamental role going forward; without them it would be impossible to effectively address all flood risks to communities,” he says.
Catchment management is also gaining interest. NCE reported in May that the National Trust is looking at soft engineering techniques in the Lake District to hold back run-off and reduce flooding downstream (NCE 27 May 2010). A similar pilot scheme is ongoing in Pickering, North Yorkshire, to assess how land management - including planting trees, creating buffer strips along watercourses and blocking moorland drains - can reduce flooding. “All those lots of little measures are predicted to increase flood storage,” says Rooke, adding that they also offer benefits in the forms of sustainability and biodiversity.

Venables says catchment management projects like these do have a role to play in complementing more traditional engineering projects. “It might well help to reduce the frequency of low level flooding events - the one-in-10 or one-in-15-year events - but soft engineering can only go so far.”
Wotherspoon agrees that these techniques are limited.

“Catchment management plans are very high level and tend not to be too useful in identifying the actual flood risks and the cost effectiveness of any interventions,” he says.

Flood barriers

Another point of contention is the effectiveness of manually operated demountable flood barriers. Dutch concrete drainage system producer Kijlstra manager Wieger Faber and director Hugo de Waal say there is too much dependence on this type of barrier in the UK. “They should step away from static overflows and manual defences,” says de Waal, proposing the use of automatic or autonomous demountables instead.

Venables agrees that manually operated defences may be inappropriate in areas where transport infrastructure is vulnerable to flooding. “We saw the problem with demountables in 2007,” she says, citing demountable barriers designed for the River Severn. “The lorry [carrying the demountables] got stuck on the motorway and couldn’t get there.” The key, she says, is “thinking very hard about what’s the right situation for the right place”.

What is agreed is that progress in flood management will have to be slow and steady. Carrying out assessments and formulating strategies is a time-consuming process, but it is critical that local government, water companies and water engineers get them right first time.

“If I had a magic wand it would be good to start tomorrow,” says Digman. “But to implement something you need to understand it first. The problem comes down to implementation.

“It’s very important that we provide value for money and we get it right. When we talk about managing water we need to understand exactly where the water is going to go.”

Of course, the spectre of government spending cuts now looms large - and nobody wants to see capital spending on flood schemes suffering as a result.

New funding models

Rooke says the Environment Agency will seek new funding models if necessary to avoid compromising on its targets. “It’s a really good driver for us to still have the same ambition, but we will have to do it in creative and innovative ways,” he says.

“The challenge is to still protect as many people but by using less resources or bringing in new resources from elsewhere.”

There could be opportunities for the private sector to be involved, or even the third sector with “perhaps some incentive from ourselves,” he says.

“We have all the tools in our box to address the technical issues, but funding is likely to be the biggest challenge”
Chris Wotherspoon, Grontmij

Experts from CIWEM’s Rivers and Coastal Group are also keen to underline the importance of maintaining public sector investment. As in all areas of civil engineering, they say, “stop/start” decisions and programmes are inefficient in terms of finances, time and human resources.

And Venables says it is important that existing flood management infrastructure is not forgotten when it comes to funding. “We’ve really got to maintain the schemes we have got,” she says. “I’d like to see the emphasis on looking after and keeping effective the assets we’ve got.”

Meanwhile, Wotherspoon says Defra’s recent funding of some local authorities’ initial surface water management plans is helpful, but it is only a start. “It will facilitate some studies but it won’t allow authorities to procure any works on the ground and there is no guarantee of any further funding,” he says. “We have all the tools in our box to address the technical issues, but funding is likely to be the biggest challenge.”

And perhaps the other biggest challenge of all, says Venables, is maintaining levels of public support for the construction of flood projects as the memory of 2007 retreats into the past.

“Keeping it in public memory is so difficult,” she says. “You’ve only got to have two dry years and people forget.”

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