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Wednesday, 16 November 2011

Water

For eastern England, today is another dry, bright day: cool, but not cold for the time of year. Good weather.

But it masks a problem. The autumn of 2011 has been unusually dry in eastern England, as in various areas of Europe. In England, the relative drought, as compared to annual average rainfall figures, affects mostly the parts of the country where the public water supply comes largely from aquifers. Aquifers are large areas of soft rock, deep underground, that can hold copious amounts of water that cab be accessed by means of boreholes. So it is essential that rainfall is at least equal to the long-term annual average to enable the aquifers to recharge and be able to supply the farms and the cities with sufficient water even in periods when there is a period of a few months with little or no rain. If the aquifers do not get the recharge, the reserve disappears.

In a drought that begins when the aquifers are full, first the rivers begin to fall so that abstractions of water from them are limited - and ultimately forbidden - to protect the ecosystem as far as possible. Once that has happened, water for humans is supplied from deep below the earth; while farmers are told that their supply is reduced, and may be cut off if the drought is prolonged. If the drought continues the supply to urban areas is limited: first hosepipe bans, the ultimately stand pipes in the streets. The prevailing British climate usually brings rain before the standpipe stage is reached: but there could come a time when this historical rescue fails to happen. The whole of civilisation, beginning with drinking and washing and the disposal of bodily waste, would become laborious and eventually precarious. Fresh vegetables would disappear, then bread and meat.

Meanwhile the southeast of England remains a magnet for migration by people from the whole of the British Isles and much of the rest of the world: the population is increasing and so the demand for water is growing and the supply cannot be assured. This is seen as a problem beyond the competence of water companies, government, or even the controlling ambitions of the eurorats. In drought Europeans turn to prayer, sorcery and other external sources of assistance for impotent humanity.

These speculations are not extreme imaginings: prolonged drought is a real and present danger: and it is way beyond the powers-that-be. Some water can be pumped through the pipes from water companies in the north and west to those in the south and east on a small scale and at a huge cost in pumping fuel; but not enough. Other ideas include bringing water in by tanker - also at immense cost - or even towing icebergs from the poles: none of these can be seen as a viable long-term solution. Suggestions to pump water short distances between rivers are anathema to naturalists who consider each fluvial ecosystem to be unique and very delicately balanced. The use of old canals raises less objection, but cost projections for a canal-based national water grid do not cover the whole country and are very significant: and there are no obvious funders for such undertakings.

This British problem is potential rather than actual; but it should be planned for, more than it is now in informal contacts between regulatory bodies and the water companies. But Britain does not yet recognise a need to address the problem as a high national priority.

By contrast much of India and of China, as of sub-Saharan Africa have already depleted massive aquifers to a depth that implies that recharge would be improbable even from a century of heavy rainfall. Well-meaning charities that provide wells for villagers exacerbate the problem, while bringing short-term gains to the current generation of Kenyans whose beans and tomatoes appear in European supermarkets. It is a commonplace for apocalyptic environmentalists to assert that the wars of the next generation will be fought for the control of water resources. It is indeed possible that governments may fight to control the flow of water down rivers or aquifers; but such control does not exempt them from the problem of how to pump such a mass of a heavy substance to the people and the farms, or how to move millions of people from their homes to the places where the captured water supplies can be accessed. War can gain territory - which means depriving others of that territory - but that does not answer to problem of bringing water into use.

These are issues that deserve much more attention than individual governments and international organisations than they have had; and public education on this issue is a major global necessity.

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