We need more subtle flooding solutions than a national grid

Senior reporter

Britain is once again facing winter flooding, the Environment Agency warned this morning. It’s hardly surprising given the ‘wettest summer in 100 years’ we were experiencing just a few months ago. At the time, however, many people were also dealing with the ridiculous contradiction of a drought and hosepipe ban when the heavens kept opening.

Climate change is likely to make floods and droughts much more common around the world. And given our general lack of experience – and therefore tolerance for extreme weather in Britain – this will probably become an increasingly important political topic over the coming decades.

Right now, however, there doesn’t seem to be an awful lot being done to prepare the country for the increased frequency of water problems: in fact, flood defence budgets are being cut. A draft water bill going through Parliament appears to focus largely on tinkering with the water market to bring bills down and encourage water companies to take less from the environment.

So what can be done about it? The most obvious idea, and one that perennially rears its head, is to create a national water grid to transport water around the country, generally from the soggy parts of Scotland, Wales and the north of England to the parched southeast. ‘The Romans did it, so why can’t we?’ proponents cry.

A recent report by consultancy Davis Langdon echoes the calls of London mayor Boris Johnson in arguing for a revival of the Grand Countour Canal plan of 1942, to build a canal linking the Scottish Borders with southeast England. Following the 310ft contour of the hills, the canal would be relatively economic, the report says, because it would require no locks or pumping to keep the water flowing.

In some ways it sounds appealing. We’re entering a new age of massive infrastructure building – HS2, new nuclear, new Forth bridge – and the case for government funded capital programmes to stimulate the economy has been bought even by many Conservative politicians. Plus the Olympics have proven that we can pull off big projects on time and on budget. An unscientific poll of Engineerreaders had almost two-thirds of you in favour of such a pipeline.

But take a look more closely at the idea and you’ll find it’s riddled with problems. Even using the gravity provided by the contours, this plan would still be massively and prohibitively expensive. Even the Davis Langdon document acknowledges Environment Agency findings that large-scale water transfers would cost four times as much as building new reservoirs to meet demand in the Southeast.

Using canals to move water around means you can’t use them for transport so any water network that integrated our existing canals would put an end to any of their other functions. Plus moving soft water to hard-water areas where the environment is based around different chemical compositions could be hugely damaging.

Boris Johnson’s response to this argument (in an article in the Telegraph): ‘This sounds pretty much like tripe to me… The chemical composition of water is H2O, and that is true across Britain.’ Perhaps we shouldn’t expect anything else from a politician who has become well known for his support of grand projects that fly in the face of evidence against them or are otherwise completely unnecessary.

But the deeper issue with this plan is that water imbalance in Britain isn’t as simple as the north has too much and the south has too little. Hosepipe bans can and have been put in place all over the country and parts of the Southeast suffered flooding this year. And we saw we can have drought and excessive rainfall at the same time in the same place. Putting in place an extensive national water grid that could pump water to and from all areas of the country would run up costs that aren’t even worth considering.

It’s no wonder that the government Environment Agency, the water industry and the Institution of Civil Engineers all oppose such a plan. But we’re still faced with the question of what can be done instead. The general consensus is that improved local water management and more water transfers across and between regions through short interconnections is the way forward.

But Jacob Tompkins, civil engineer and managing director of UK non-governmental organisation Waterwise, argues that we need to go further and institute a complete change of philosophy. ‘Engineering has moved on in the 2,000 years since the Romans,’ he says. ‘We need a modern solution to a 21st century problem.’

The answer, in his mind, is an integrated water management plan across the country that works with nature rather than fighting against it. This means focusing on small-scale storage rather than a few big reservoirs that empty and fill rapidly as the weather changes; allowing flooding to occur on farmland so we get less runoff into swollen rivers and more water into underground aquifers; and reducing demand using water meters and other water-saving incentives.

I’m not quite convinced that all these ideas would be as simple and effective as Tompkins seems to believe. True, it’s ridiculous that most people in the UK are still charged a flat rate for water usage. And improved water storage at a local level across the country appears sensible – our big reservoirs certainly don’t seem to be doing the job.

But I’m not sure whether most farmers would accept the inconsistency brought by allowing their land to flood, even if a sustainable way to compensate them could be found. And if we were to do this, it would require the dismantling of existing flood defences, a costly exercise that I think would be greeted with much unease by the public.

However, Tompkins is right that the dramatic change in climate and the effects that will have on the UK’s water supply require a change in thinking. Difficult problems require subtle solutions and a giant infrastructure project won’t necessarily provide that. But whatever we decide, the work needs to start now if we want to avoid the huge financial and personal costs of yearly floods and droughts.