Jeff Green | Mar 16, 2006
March 16, 2006
Back toHomeMarch 16, 2006
Global Change Part 4:Water
Commentary by GrayMerriam
In the Land O’ Lakes we seldom think about water shortage. We are supremely fortunate to have all our lakes and rivers and wetlands. But global changes will bring water shortages into our lives before long.Producing one tonne of grain such as wheat takes about 1000 tonnes of water. Countries with water shortages (often dry areas relying on irrigation) can’t produce the grain so they import it. That is equivalent to importing water. If the needy country happens to have oil, they trade oil for grain which is the same as trading oil for water. Global economic flows are hidden movements of water across international boundaries.
Trading of water, or rights to water, was initially a local business. And that local trade in water still is very lively. It had a simplistic economic basis as well as a basis in human population geography. Those two elements, economic power, and population numbers meant that water would flow from the countryside to the cities. From agriculture to industry and commerce. It takes 14 tonnes of water to make one tonne of steel worth about $600 but it takes 1000 tonnes of water to make one tonne of wheat worth about $175. We each want a daily ration of about 4 litres of water, in one form or another, but our daily food ration requires about 2000 litres, 500 times as much, to produce it. So cities and commerce often take priority when politicians set policy for water use and distribution. Consider the ‘cities first’ statements in our recent election. What happens when such priorities are followed?
Water rights, and trade and sale of water rights is a simple economic response to competition for a resource. In the U.S. , the Colorado River's water now rarely makes it to the Pacific Ocean . It is all used up en route because priority was given to cities such as Los Angeles and to high-value cash crops that could be grown in marginal areas provided they were intensely irrigated. Similarly, in the State of Colorado , rights to almost all water supplies have been sold. As a result future development of both economic and natural systems is dictated by the owners of those water rights.
Following such policies, whether democratic or not, has made rivers run dry in the U.S., China, southeast Asia, India, Pakistan, central Asia, and North Africa. Drying up rivers also has dried up lakes. The best-watched example is the Aral Sea in central Asia . Politicians in Moscow saw the economic potential of cotton. Diversion projects moved freshwater from the Amu Darya and the Syr Darya into irrigation for the cotton project around the Aral Sea . The cotton production did not fulfill the politician’s economic dream but they did not give up easily. The eventual result is that the seaport economy of the Aral was eliminated, as was its fishery when the lack of freshwater inflow combined with the high evaporation pushed the salt concentration up a lethal level for fish. The water’s edge is now over 250 kilometres from the original shoreline. Silt, sand and salt from that exposed mudbed is picked up by the drying wind and deposited on farmland, taking it out of production the opposite effect to the politicians’ dream.
The Aral is not the only ‘lake’ to be dried up by mismanagement of water. In western China , over the last twenty years, 2000 lakes half of all lakes in that province have disappeared. Around Beijing , over 900 of about 1000 lakes have gone. Similar losses have happened in India , Pakistan and Iran . Excessive diversions from rivers and depletion of groundwater tables are the causes.
Groundwater tables are being depleted on all continents. For water tables such as the Ogalalla, running from the southern Prairie Provinces to the Texas panhandle, or the great water table under northern China or under Saudi Arabia , overpumping simply means the end of the supply because these aquifers are not replenishable. As their level is lowered, costs of pumping increase and eventually became impossible. Then the farmers must shift to dryland farming without irrigation. For heavily pumped aquifers that are replenishable, the rate of removal eventually matches the recharge rate and removal above that rate is impossible. Users must adjust from higher demands to that limited rate.
In northern China , the replenishable aquifer has been used up and wells are now being drilled up to 1000 metres deep to tap the non-replenishable, deep, ‘fossil’ groundwater table. Since 1998, the Chinese wheat crop has fallen by more than the total Canadian wheat crop. Rice production also is dropping. In India , the U.S. and the Mid-East, oil drilling techniques are being used to drill 1000 metre and deeper wells to compensate for overpumping. Groundwater is not being managed. It is being mined with no view to the future. In western Yemen , in the region of their capital where many of their 21 million live, projections by the World Bank indicate that the current unsustainable use of water will pump their groundwater dry by 2010.
So why should we, here in the Land O’ Lakes be concerned about water shortages elsewhere? In humane terms, water shortages cause human misery either directly and locally or eventually as the water shortage causes food shortage. The Council of Canadians has uttered a policy that every human being should have access to a clean supply of water no matter where they are. A humanely sound position. But, realistically, can humans live safely in all the places where there now are large numbers of people? Can large numbers of people settle in desert areas where formerly only a few nomadic people were able to survive? In the Sahel region bordering the Sahara , where aid projects have dug wells and put in pumps, many people gathered and brought their flocks. From satellite views, it was possible to see an ever-growing circle of denudation around those wells. Too many people and too many goats staying in one place all the time simply overcame the ability of those desertic areas to support them. Artificially supplying water to all water-limited areas where humans make settlements is not possible. There are some absolute limits to how humans can force themselves into unsuitable habitat just as there are limits for all other living beings.
But given our penchant for engineering challenges, we undoubtedly will continue trying to manipulate water resources in favour of humans. What does that mean for the Land O’ Lakes? It means that we have a treasure of water and others will come after it. In the late 60’s, the Parsons Project was designed in California to build a series of canals and dams that would move freshwater from northern Canada into the U.S. In the 70’s, then U.S. Senator Frank Morse of Utah stood on the steps of our parliament and proclaimed that we would be inhumane of we did not give the good citizens of Utah a supply of our water. They needed more subdivisions with more lawns to water, among other things. One Canadian politician, about the same time, showed a complete ignorance of ecological processes by arguing that water flowing into Hudson Bay was wasted because it had already flowed past all the people. Those attitudes are still present and we have added the complexity of a free trade agreement that does not give absolute protection to our water but instead threatens to give away rights of control of the water in a lopsided economic tug of war.
For more discussion, see “Plan B 2.0”, 2006, by Lester Brown, from the Earthwatch Institute or "Water' by Marq de Villiers, 1999, Stoddart or go to www.earthpolicy.orgOther Stories this Week View RSS feed