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Architects: the solutions to flooding are both big and small in scale

From double basements and jacking up houses to large-scale planning, the act-now solutions to flood-risk Britain are about design integration

In the week that Nicholas Stern, the author of the landmark 2006 report into the effects of climate change, called for immediate action to make the country more flood resilient, architects have demanded a ‘visionary, strategic and radical’ masterplan to combat the threat of future catastrophes.

The call came as thousands of homes were submerged following the wettest January in 250 years and as flood warnings remained in place across southern England.

ADP chair Roger FitzGerald called for a long-term national development masterplan setting out ‘where new housing should be located and taking account of areas vulnerable to future flooding’ for the next 25 years.

He said: ‘Governments are too short-term in their thinking, so architects and planners should take the lead.’

Governments are too short-term in their thinking, architects and planners should take the lead

Former CABE chief executive Richard Simmons agreed, explaining the most effective natural methods of flood prevention would require ‘unfashionable behaviour such as large-scale planning and holistic systems design’.

The problem is potentially huge. According to recent figures, around 200,000 homes were built on floodplains between 2001 and 2011.

Flooding graph

Tony Hutchinson of Capita Symonds said: ‘Given it took 30 years for the Thames Barrier to be designed, funded, agreed and built following the major flood in 1953, strategic, tactical and operational measures need to be taken now.’

The comments come as a growing number of voices are calling for a blanket ban on building in flood-prone areas – including councillors in Windsor and Maidenhead where 12,500 homes are being planned on land that is currently submerged.

Committee on climate change chair John Krebs told The Sunday Times: ‘We are still slapping up homes and business properties in floodplain areas. We have adopted the “build and defend” approach in the past and we need an honest assessment. Is build and defend the right way, or do we say that we will stop building homes in flood-risk areas, we will just build elsewhere?’

It is possible to build cleverly on the floodplain - but it is just not happening

Flood consultant Mary Dhonau – dubbed ‘Mary Queen of Floods’ – told the AJ: ‘Yes it is possible to build cleverly on the floodplain. But it is just not happening. Until “clever” building becomes the accepted norm, then a halt should be put to it.’

Mark Wilson, chief executive of insurance giant Aviva, told The Sunday Telegraph: ‘As a nation we need to build more homes, but the cost of development must include the cost of defences. Let’s be crystal clear: no defences, no development.’

However Baca Architects director Robert Barker, who has written for the RIBA Sustainability Hub on flood resilience, has spoken out about being over-cautious.

He said: ‘The question about building, or not building, on floodplains is too simplistic. We need to learn to live with water, understanding the effects and managing the consequences.’

Rising to the challenge, other architects suggested a range of measures that flood victims and housebuilders could deploy to combat the destructive impact of future flooding catastrophes.

Kiran Curtis of KCA architects said: ‘The first thing architects should consider is the nature of flood risk: “How high does the water get, how quickly is it moving and is it ground, fluvial or surface water?” The second course of action is to try to prevent that water getting to the houses in the first place.’

Curtis’ proposals included raising or re-profiling sites to push water away, and create zones where excess water can be stored. Living areas could also be raised off the ground floor. ‘It is not desirable, but it is viable and there are areas where people live in that way.’

‘With one of our schemes the ground level area is almost sacrificial with surfaces that can be cleaned quickly; while the kitchen and living areas are a metre above the floodplain.’

But he drew the line at floating houses: ‘There are some very interesting examples in the Dutch polders that are allowed to gently flood in a managed way. Here it is a bit different as there is rapid ground water flooding and fluvial flooding.’

Other suggested solutions include running electrics from the ceiling down the walls and specifying non-porous surface materials.

Peter Morris of Peter Morris Architects suggested that new houses in flood-risk areas could be built on elevated concrete slab and pile foundations. He said: ‘This allows below-ground water to drain freely and quickly. In the eventuality of long-term water level changes, the houses can be jacked up to a higher level. Combined with a portal frame, this would also allow for greater freedom in design, with two stories of column-free interior space, corner views, and double height spaces.’

S333’s Dominic Papa meanwhile revealed a double basement concept which would allow both new-build and retrofitted homes to rise and fall with the floodwaters.

About the idea, which is being discussed with housebuilders, Papa said: ‘Ordinary waterproof basements when immersed are quite sufficient to lift conventional timber or brick houses. The addition of guides and a surrounding “second basement” to temporarily hold the water allow standard house types to rise and fall in emergency conditions appearing exactly like a static house at all other times.’

Further comment

Richard Simmons, former CABE chief executive

‘Designers must think differently about flood prevention. The Environment Agency’s strategy Making Space For Water replaces the old ways with more natural methods that rely on basic hydrology and the ecosystem. They are more resilient to climate change, but have drawbacks. They require unfashionable behaviour such as large-scale planning and holistic systems design.

‘I applaud architects that are creating ways to flood-proof buildings. Groundwater flooding mandates new thinking under the floor. Flooded homes need retrofitting. But we must masterplan on a bigger canvas, factoring in landscapes up and downstream. And while some floodplains must be labelled ‘best avoided’, we can’t avoid them all. So, we need more upstream woodlands, sustainable urban drainage systems, rainwater harvesting, plenty of green spaces, permeable surfaces, storage areas for floodwater and soft defences. The RIBA, Landscape Institute, Royal Town Planning Institute and Institution of Civil Engineers should partner to foster solutions.’

 

Robert Barker, director, Baca Architects

‘We need to bring water to the forefront of planning and design. We must stop relying solely on flood defences, which if they fail or are overtopped can be devastating.

‘If we made space for water in all new developments, we would actually start to reduce flood risk across the country. Minimum standards should no longer be delayed, and we should look to reward development that provides more space for water, by using for example Long-term Initiatives for Flood-risk Environments (LifE) silver, gold and platinum standards. Innovation to tackle challenging areas like the Somerset Levels and Moors should be encouraged. This could be piloted through an innovation license scheme which could grant (or revoke) a limited number of licenses to build based on meeting high-level objectives. Land should also have multiple functions so that flood-able parks, squares and play areas serve the community everyday but in times of flooding these can then be called upon to provide flood storage.’

 

David Demeritt, professor of geography at King’s College London

‘We require a mix of three strategies. Firstly, we need to spend more money. The UK flood budget is around £535 million compared to £4.5 billion in the Netherlands. Secondly, some places are going to have to be abandoned. It’s already happening on the east Coast of England where we are letting houses fall into the sea. Thirdly, homes can be flood-proofed by using flood resilient design such as flood gates and ground floor-tiling. Fourthly, upstream retention can slow water moving into lower levels of catchment. Having greenroofs in cities and paying famers in uplands to have trees and retention reservoirs may help.

 

Peter Stewart of Peter Stewart Consultancy

‘Over the longer term, the forces of nimbyism in some areas tend to direct new housing away from the best places to build it (best from the point of view of future residents, who have no representation) and towards unsuitable land where there are fewer people, or fewer influential people, who are likely to object – e.g. flood plains.

‘This may not be directly relevant to the present situation though - none of the areas I have seen on the news that are flooded look as if they are very recent developments, though don’t know if that is representative.  But I think the issue I raise is storing up problems for the future.’

 

Tony Hutchinson, Capita development director for housing

‘Regardless of what is the underlying cause there is evidence from California to Australia to Somerset that the earth’s climate is changing. Given that it took thirty years for the Thames Barrier to be designed, funded, agreed and built from the major flood in 1953 to becoming operational in 1983 strategic, tactical and operational measures need to be taken now. 

‘The threats from extreme weather need planning for and managing every bit as carefully as any other risk to our national interest.  Is the future threat that requires £35 Billion to be spent on fighter aircraft a more real and present danger  than the inundation of great swathes of productive countryside, rural communities and major cities, shouldn’t we be protecting jobs, jobs and livelihoods in next few week, months and years?

 

Chris Roche, founder-director of 11.04 Architects

‘Architects typically carry out a site analysis as part of the development appraisal however this would not normally include a Flood Risk Assessment.

‘It is conceivable that an architect would be found negligent in the future for not advising a client that the site was at risk of flooding and designing the property accordingly.

‘A Flood Risk Report can be purchased online for £30 – I bought one this morning for the first time in 25 years.’


Trudi Elliott, chief executive of the RTPI

Although of no comfort to those affected by flooding, most of the homes flooded are historic settlements. With one in six existing homes at risk of flooding, relatively little new development is now approved in areas at high risk of flooding. According to the Environment Agency, in 2012/13 there were just 543 residential units/homes that were granted permission despite a sustained objection from the Agency. Modern design should mean that if there is building in flood prone areas, the effects are mitigated as best they can be.

Planning policy hasn’t changed. Flood avoidance and mitigation remains a priority for planners. The National Planning Policy Framework (NPPF) contains all the important elements of PPS25, the previous policy on development and flood risk. Inappropriate development in areas at risk of flooding should be avoided by directing development away from areas at highest risk, but if development takes place in the flood plain it may only happen if it is made safe and does not increase flood risk elsewhere.

With relief efforts still underway, it is not the time to try and draw conclusions or lay blame. But policy makers and those involved in all stages of the development process will need to review what we do to ensure that we are doing everything we can to lessen the effects of climate change.

 

Dominic J Eaton, director at Stride Treglown

I heard an interesting comment on the news the other day, where a resident affected by the flooding in Somerset commented that the government is often quick with emergency aid abroad but have been poor in their response to emergency situations on their own doorstep. This does appear to be the case with thousands of households who have been affected by the floods and power cuts, having to wait for weeks for help. I think the response by government to the flooding disasters that we see on our televisions has been poor, and interesting, when they eventually wake up to what is going on, all the various political parties come down to the West Country on mass, and blame each other or the Environmental Agency. This is not helpful.

I support Cameron in the idea that whatever money is required is made available. I don’t know the details, and it is always difficult to comment without the full facts. But it seems to me that there will be a number of various initiatives required to action this problem. In the short term there are the houses that have been flooded and are at risk of flooding, which needs immediate attention. Then there are the boarded strategic decisions and actions required to prevent flooding as source, and by this I mean dredging rivers and forming barriers to hold back and divert the flood water. Although I heard an interview with the EA where they were saying that dredging wasn’t the answer? Are we any closer to knowing what to do, even if there was the money available to do it.

However, when I think of flood barriers I think of New Orleans and the constant risk of these barriers being breached with catastrophic consequences.

There might also be properties that are constantly venerable to flooding and beyond any reasonable help with regards flood prevention. I know a developer client of ours who has developed a flood prevention package which through damp proofing to the external envelop and specially designed external doors etc., can protect a house from flooding if water levels raise to a maximum given level or around 500mm above FFL. For around £8,000 I think that’s good value given the inconvenience and cost of drying out your house, replacing carpets, furniture, kitchens etc. and the possibility of hotel accommodation.

The insurance companies also appear to like this approach and are prepared to insure properties that incorporate these localised defences.

Replanning a house might be a possibility, but I could envisage numerous issues resulting from the conversion of the ground floor into garages. Your three bedroom house becomes a one bed Fog, and there will still be accommodation on the ground floor such as the entrance lobby and stairs. I can’t really see this working and being a feasible solution to the problem.

I would be interested to know where flood levels have been provided by the EA to inform new developments with regards minimum ground floor finished floor levels, whether these levels have been exceeded with the recent floods and the extraordinary weather that we have been experiencing. This guidance is based on the expectation of exceptional circumstances happening once in a hundred year. Although it now feels that these once in a hundred year disasters are happening every year.   

I think these emergencies will have a negative impact on plans to build more urban extensions and ‘garden cities’ in the South and South West of England. Ironically, if these mean not building on Green Belt, I think that would be a good thing, with pressure growing to fully utilise the extensive brown fields sites available.

House purchases will be much more discerning about where they buy, and the risk of potential flooding in the area, and so they should. This leaves residents in flood stricken areas stuck with a property that not only has no value, but has the potential to flood, which by current standards is happening almost every year. I think the localised flood prevention package has to be an option, and certainly would be something that I would be considering if I were in that situation.

 

 

 

 

 

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