Parts of the UK and other western European countries affected by this winter’s storms and heavy rain are finally starting the long process of recovery. Flood waters are receding, but even with pumps will take some weeks to clear. Many months will be needed before houses and commercial premises directly affected will be dry and fully habitable again. The task of repairing storm-lashed buildings and infrastructure is now getting underway.
Most of the unfortunate people affected were well aware they were in vulnerable areas, but this year’s rains have been unprecedented for many areas and waters have risen far higher than in a normal year. In the Somerset Levels, a low-lying area in the west of England, lack of dredging of the main rivers in recent years has been blamed for exacerbating the situation.
The reasons for this appear to have been two-fold: the prioritisation of wildlife and the higher cost of disposing of silt from rivers as a consequence of EU Waste Framework Directive. Silt can be a valuable and fertile addition to farmland, but a proper assessment has to be done, and waste silt may have to go to (costly) landfill.
Pressure from local residents, including livestock farmers who have had to evacuate their animals and whose livelihood has been ruined, has quickly resulted in a reversal of policy, as reported by the BBC: Somerset Levels river dredging ‘to start in March’. The Environment Agency has announced that key stretches of river will be dredged as soon as it is safe to do so, and is preparing a 20-year plan for submission to Owen Paterson, the responsible Secretary of State.
The country which has of course had more experience than any other of dealing with actual and potential flooding is the Netherlands. Large parts of the country are below sea level and the polders have been drained and reclaimed from the sea. These areas can only be used for building and farming because of a complex system of flood defences, drainage channels and active pumping. Some of this expertise may be called on for the UK’s current problems (Dutch engineers could be called in to sort out Somerset Levels flooding).
But this is not a clear-cut issue. According to George Monbiot, writing in the Guardian, Dredging rivers won’t stop floods, it will make them worse. His point is that dredging only allows a small proportion of the flood waters to drain away and, in so doing, creates a faster-flowing river capable of causing more damage downstream. He supports greater planting of trees and flooding of land on higher ground to reduce flooding further downstream. He has a point: dredging alone is certainly not the full answer and intelligent management of the whole river system is important.
However, this whole debate tends to focus on a number of value judgements. Whereas at one time protecting communities from catastrophic flooding would have been the number one priority, a greater emphasis on biodiversity and natural habitats has made policy more complex. Whether or not dredging would have made a significant difference to the Somerset Levels is a moot point. These rivers used to be dredged but had been undisturbed for a number of years in large part because of habitat concerns.
The present focus on conservation is, in many ways, admirable. Having developed a prosperous, modern society (not without its problems, of course, but the great majority of us are incalculably better off than even recent generations) we now have the time and resources to value wildlife and habitats and try to preserve it. But the downside of this is a tendency to leave nothing unchanged, whereas in fact most of the ‘natural’ countryside around us has been shaped by humans and would be very different in our absence.
Some ‘deep Greens’ would prefer to see our species disappear and allow other life to flourish on Earth but such self-loathing and guilt is fortunately rare. In diluted form, however, it surfaces as today’s concern about over-population, seen by many as the root of all other environmental problems. In practice, our adaptability and inventiveness means the normal constraint of carrying capacity does not apply as for most other species. The development of farming meant that the upper limit on sustainable human populations was raised and the use of synthetic fertilizer (and, in the future, crop plants which can fix their own nitrogen) has kept the food supply growing faster than population.
Deep and not-so-deep Greens argue that we are using the resources of more than one planet and that our current civilisation is unsustainable. Although this kind of argument has become widely accepted, it requires a number of assumptions and specific analysis to arrive at this conclusion. History suggests that scarcity of particular resources creates incentives for change and that human development does not follow a straight-line extrapolation for long.
Farming itself has transformed the countryside. Great areas of forest were cleared to grow crops, and hedges planted to separate fields. In so doing, the balance of wildlife was forever changed, with for example the relatively small number of birds living in temperate forests largely displaced (but more than compensated for) by the greater variety of species living in more open habitats.
Similarly, the draining of the Fens in East Anglia in centuries past (by the Dutch, already masters at such works) created some of the most productive farmland in the country, got rid of malarial swamps and opened up the region for more inhabitants. Like the polders, the Fens are actively drained and provide their own wildlife habitats. Failure to manage the land properly would be a catastrophe for the population.
The Somerset Levels have been vulnerable to regular flooding for centuries, but the present (largely manmade) drainage system normally keeps this to manageable levels. Some would argue that lack of dredging was an example of failure to maintain this system. Critics also point out the £31 million spent by the Environment Agency to create a bird sanctuary at the mouth of the river Parrett: more than six times the total cost of dredging this and the other rivers in the area.
Finding the balance between human needs and natural habitats is never easy, but some conservationists forget how resilient Nature can be. We only need to see how quickly water fowl flock to flooded fields or how populations of particular species bounce back after a particularly cold winter has decimated their numbers. We cannot be complacent, and conservation is important, but it’s equally important that we put the needs of our own species first.
Martin Livermore
The Scientific Alliance
St John’s Innovation Centre
Cowley Road
Cambridge CB4 0WS
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