Monday 20 February 2012

Water water everywhere – except when there isn’t!!

Whilst I am writing this there is a meeting going on in London between government, the water industry and the Environment Agency to discuss a likely drought this year.

It may seem strange, in wet, soggy Britain to talk about a drought, especially in winter, because it’s always raining here isn’t it? Well, when you think about it, how much rain have we actually had? A bit of drizzle last week, one downpour a few weeks ago, but apart from that - almost nothing.

Reservoirs, which supply about 20% of our water, are less than half full. 80% of our water comes from underground aquifers, mostly under the South Downs, and these pretty low on water too – probably as low as they have ever been. They are supposed to be full in winter and only get low later in summer. Streams that should be coming out of the South Downs are either low or non-existent, and areas that should now be wet are dry.

Obviously there will be wildlife effects – fish won’t be able swim upstream to spawn, wetland birds like redshank, snipe and lapwing will suffer, there will be fewer invertebrates that feed the rest of the food chain and wetland plants will be more restricted and flower less. Low water levels in rivers will also mean that pollution incidents will be more severe as there is less water to dilute them.

People are therefore coming forward with their own solutions to the problem – desalination plants (hugely expensive, use up large amounts of energy and produce saline pollution), a “national grid” for water (but water is heavy and it would take enormous amounts of energy to pump over large distances) and, of course, more reservoirs.

But reservoirs are not a panacea. To build them we would have to flood what is already there so could wipe out any existing wildlife interest, they are also hugely expensive and might take 20 years to become operational. Also – do the sums – we only get 20% of our water from reservoirs so even if you managed to double their area (unlikely) you would only increase the amount available by 20%. With the population increases, and the per capita consumption increases we talk about, that will not get us very far. And that’s assuming there is enough rain to fill them.

No – the problem is deeper than this. There are too many of us, each with too high a water demand on too small an area. The result is that there is now less water per head of population in the South East than there is for people in Ethopia.

We may be able to achieve some very minor improvements through these technological fixes but we are running up against real environmental limits. Overall, techno-fixes like these will be about as successful as doing the rain dance that was talked about on BBC local radio this morning. And techno-fixes will come with their own problems which could be as bad, or worse, than water shortage.

Water is one of those resources that fundamentally questions our basic assumption that we are able (indeed have the right) to expand consumption in all directions no matter what.

There is only so much water, damage to wetland wildlife indicates that we have over-stretched the resource and the only answer is to live within environmental limits rather than imagine that there are magic technological solutions. This means using less water.

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