human water management

Human management of freshwater has always been at the center of civilizations. Not only did most human cities emerge along rivers, but historically we remember civilizations that grew powerful because they learned to irrigate their crops better, and then to plumb their cities more effectively. At the dawn of civilization, the Sumerians emerged as dominant in their region after building extensive dams and canals to use the flood waters of the Euphrates for irrigation. The Romans, who inspired centuries of history around the Mediterranean shores, are quite possibly best remembered for their incredible aqueducts, which made farms and cities possible in deserts, and allowed hundreds of thousands of Romans to live closely together--aided by public fountains and baths, fire-extinguishing capability, complex sewers, and regular street-washing. In recent history, drilling for aquifers and channeling rivers onto dry areas permitted the rapid development of the American West, creating abundantly fertile agricultural centers in grassland/deserts like the Central Valley of California. Giant river damming projects also produced large amount of electricity, helping new cities blossom. Thus the large-scale management of western American water--damming rivers and drilling into aquifers, became in this century an idealized model for economic development around the world.

There is little doubt that the arrogation of freshwater will remain a central issue, motivating, creating, and threatening our societies into the next century as well. This is true in large part because exactly the same management practices that brought great wealth to people have often simultaneously destroyed it, just over a longer period of time. Many ecologists now agree that the deserts of the Middle East were largely created by human practices, beginning with the over-irrigation of fields. Too much water has left behind arid landscapes—because it washed away topsoil or brought salt to the fields from upstream (by gravity and evaporation) or from deeper ground (by osmosis). Despite huge aqueducts, the Mediterranean fields that once propelled the Roman Empire grew less productive and then insufficient, contributing to the Empire's relocation east to Byzantium(1). In recent history much of the last century's growth in population, in the U.S. and the developing world, has been dependent on unsustainable water sources, making billions of people alarmingly dependent on falling aquifers and dwindling rivers. Many mechanized farming practices and the careless paving involved in rapid urbanization are both accelerating the trend toward desertification (2).

At its worst water scarcity and misuse is expected to lead to war. Both the United Nations and the CIA have predicted future wars over water. Former UN Secretary General Boutrous Boutrous Ghali has predicted that the next war in his region will be over the Nile. In the last fifty years Egypt has already sent troops into both Sudan and Ethiopia to protect the headwaters of the Nile, and the population of that region is expected to double. A primary Israeli motive in the Six-Day War was to secure its water supply by conquering the Golan Heights from Syria. Today, as millions more Israelis are recruited into the country, and as Jordanians and Palestinians swell their own populations, the water they must share, from the Sea of Galilee down the Jordan River, is diminishing. In southern India a long-standing dispute between the upstream city of Karnataka and the downsream city of Tamil Nadu has lead to riots and fighting in the streets (3). While water tables, in places from China to South Africa to the American Midwest, fall from overpumping, and an increasing number of rivers, from the Yellow to the Ganges to the Colorado, fail to reach the ocean at certain times of year, the proportion of people without access to clean water is over 20%, while the number without proper sanitation sewers is over 30% (2). Water shortages and its effects are arguably much more urgent than the fossil fuel shortages that have received so much more attention in the
U.S..

In countries that can afford it, water scarcities can be dealt with by importing water, especially the more economical "virtual imports" of water. One ton of grain is roughly equivalent to 1000 tons of water, and one ton of beef can require more than fifty times that. So, when the water tables of northern China collapse below the minimum level, as they are expected to in the upcoming years, and the farmers are unable to grow as much food, the extra demand on the international grain market will likely cause a sudden increase in price. After watching Chinese demand increase the international price of commodities like oil and copper, it is less difficult to imagine a sharp increase in the price of grain (4).

Even in places where water scarcities are less imminent, big changes are in the works. World Bank loans in the developing world are increasingly contingent on privatizing water utilities. States and cities in the U.S. unable to find the money to fix the aging infrastructure of their water works are beginning to look more favorably on privatization schemes. Between 1990 and 2002 the number of people receiving tap water from private companies increased from approximately 50 million to 300 million. Water has long been the domain of governments -- some argue that large-scale water management was the historic motivation for big governments in the first place. So as private corporations move into this turf, the battle will likely be contentious. Citizens of Cochabamba, Bolivia already rioted after an American consortium bought full rights to a region's water, even including personal wells, and then raised the price up to 150% (5).

All these threats create a situation where water conservation and re-use make more sense than provisioning more water. Compared to the costs of proposed desalination projects, water pipelines and tankers, increased food prices, and military budgets, the cost of water efficiency is much more affordable. And there are several obvious methods to avoid waste. Drip-irrigation, with water placed precisely where and when crops need it, can increase agricultural yields with half as much water. Eating plant calories rather than meat calories, as alluded to earlier, can be 50,000 times more water-efficient. Choosing native vegetation for landscaping can completely eliminate artificial watering. Collecting and using the rainwater that falls on the roof can simultaneously reduce the burden on stormwater systems while providing surprising quantities of the freshest kind of water. Using purified water only for drinking and washing, then reusing the resultant gray-water for toilets, and then reusing toilet water for landscapes are simple ways to get more out of a smaller amount of water. With such techniques households in many parts of the world can become independent of water delivery pipes (6).

As desertification becomes a more obvious problem, related to loss of agriculture, habitat, and species, poisonous dust storms, and depleted ecosystem services like weather stability, it makes sense to make water plans on a larger scale. Digging extensive swales and terraces, and nurturing vegetation in certain dry areas can increase the amount of rain water held in the soil. With more water in the ground, more rain can evaporate to areas further from the ocean, with the possibility of shrinking deserts, greening the land, protecting species, and even increasing the total biomass of life (7).

How we decide to manage fresh water into the future may define our civilization even more than it has in the past. The natural political relationship between those upstream and downstream will become more obvious, and may even re-orient political domains from national boundaries (based more on languages and strategic military factors) to watersheds. How we answer questions about who owns water and how much the poorest should pay for it will define how members of our society relate to each other in a fundamental way. Our ability to learn from long-term, ancient mistakes with water management may even allow our civilization to transcend itself and become one that reverses the drying up of Earth. Instead of causing erosion, salting, and siltation, instead of being a people who drain wetlands, we can become people who reverse erosion and thicken moist soils, refill wetlands, and water the desert.

But the optimistic forecasts are not inevitable. Or, rather, people may not shift towards more intelligent management before leaving a stain of deaths and wars in our memory. Minimizing this kind of priceless cost will take more people thinking more broadly about water planning, and then communicating better ideas with each other. The rapidity and depth of this project will be historically significant.

1. Ponting, Clive. A Green History of the World. Penguin 1993. pp. 68-88
2. Brown, Lester, and Brian Halweil. "Population Outrunning Water
Supply" Worldwatch Institute Press Release. Sept. 23, 1999
3. Gleick, Peter. "Water Conflict Chronology."
www.worldwater.org/conflict . August 18, 2003
4. Brown, Lester, and Brian Halweil. "China's Water Shortage Could
Shake World Water Markets." Worldwatch Press Release. April 22, 1998
5. Marsden, Bill. "Cholera and the Water Barons." The Center for
Public Integrity. August 2004
6. Hawken, Paul, Amory Lovins, and Hunter Lovins. Natural Capitalism.
Little, Brown and Company. 1999 pp. 213-233
7. Mollison, Bill. Permaculture. Tagari 1988. pp 308-410