-Susanne Charlesworth is a member of SUDS – Sustainable Drainage Applied Research Group, Coventry University. The opinions expressed are her own.-

The scenes of flooding in Cumbria are a shocking illustration of how Britain's ageing drainage infrastructure is failing.

The function of the majority of drainage structures is to remove water from inhabited areas as soon as possible via so-called receiving watercourses as conduits to carry excess water away. Unfortunately, cities and towns have grown beyond capacity, back-up floodplains are built upon, and water overflow has nowhere to go.

Householders are shown on television blaming the government and demanding that something must be done to prevent flooding.

In my opinion, part of the solution lies in sustainable drainage, which mimics nature by encouraging filtration via permeable and vegetated surfaces and detention via ponds, wetlands and slowly flowing water.

By slowing the water flow, SUDs offers a way of attenuating the storm peak, allowing the water to slowly dissipate. As it does this, pollutants are sifted out of the water. Since many SUDs devices involve vegetation, the sustainable approach also enhances biodiversity, amenity and local landscapes.

You would think planners, Local Authorities and even individual householders would be falling over themselves to incorporate SUDs into their built environment. But no. While SUDS have been around for several decades, particularly in the U.S., Sweden, France and latterly in Scotland, uptake in England and Wales has been slow.

People argue that the cost is prohibitive and that it is difficult to maintain. Negative views could be countered by research and development, education and information.

There is also the issue of money. Research and development is expensive.

Legislation in England and Wales does not necessarily encourage the implementation of SUDs. Rather, it has get-out clauses to enable SUDs to slip down the agenda.

The problem is more wide-ranging than this, involving everything from the trend for paving front gardens, to wider issues of SUDs devices such as wetlands actually being used as water treatment installations rather than “natural” ecosystems which area protected from dirty urban water.

There is no way I would suggest that SUDs would have prevented the current flooding, but it could have helped. The likelihood is that winters in Britain will be wetter, and the weather more stormy in general. We need, therefore, to plan now for what looks like uncertain times ahead for the British weather. If the future is wet, then the future has to be SUDs.

We seem to hear more and more about natural weather disasters – are these signs of global warming? 

Or do they just illustrate the unpredictability of the weather?

Luckily, Hurricane Gustav doesn’t seem to have inflicted devastation on the U.S. Gulf coast comparable to Katrina in 2005. On the other side of the world, the worst floods in India’s Bihar province in 50 years have displaced about three million people and killed at least 90.

Achim Steiner, head of the U.N. Environment Programme, says that more powerful hurricanes and more floods are in line with predictions by the U.N. Climate Panel of ever more disruptions linked to a build-up of greenhouse gases.   

The panel said in a 2007 report that global warming was already “unequivocal” and that it was at least 90 percent likely that human activities — led by burning fossil fuels — were the main cause of warming in the past 50 years.

It said observed shifts include “changes in arctic temperatures and ice, widespread changes in precipitation amounts, ocean salinity, wind patterns and aspects of extreme weather including droughts, heavy precipitation, heatwaves and the intensity of tropical cyclones.”

And insurer Munich Re says there were 400 natural catastrophes worldwide in the first six months of 2008 – the most recorded in any single year was 960, in 2007. Some of course are unrelated to the weather — such as the devastating earthquake in Sichuan, China, in May in which 70,000 people died.

It’s of course a stretch to turn such insurance statistics into ’smoking gun’ evidence of global warming caused by human activities. Devastating floods and hurricanes have happened since long before people were burning coal or oil.

Still, most governments say that it makes sense to invest now to try to fix the problem of climate change than wait for consequences that may be a lot worse. Should extreme weather events be a wake-up call for more action?

What do you think?