Nature is losing the battle for water

The world's deepening freshwater crisis - currently affecting 2.3 billion people - has already pitted farmers against city dwellers, industry against agriculture, water-rich state against water-poor state, county against county, neighbour against neighbour. Certainly, there is no reason why inter-species rivalry over water, such as the incident in northern Kenya, won't become more commonplace in the near future.

Elephants at a water hole in Kenya.
As humans expropriate more and more
water, there is less to support
wildlife and ecosytems.
� Don Hinrichsen

Sixfold increase in demand

According to Krchnak, who co-authored a report on population, water and wildlife, the competition for freshwater resources is undermining development prospects in many areas of the world, while at the same time taking an increasing toll on natural systems. As more and more water is withdrawn from rivers, streams, lakes and aquifers to feed thirsty fields, the voracious needs of industry and escalating urban demands, there is often little left over for aquatic ecosystems and the wealth of plants and animals they support. In effect, humanity is waging an undeclared water war with nature.

Clearly, nature is losing. Currently, humans expropriate 54 per cent of all available freshwater from rivers, lakes, streams and shallow aquifers. According to water expert Sandra Postel, Director of the Global Water Policy Project in Amherst, Massachusetts, this percentage is expected to climb to at least 70 per cent within 25 years, reflecting population growth alone, and by much more if per capita consumption continues to rise at its current rate. If the past is prologue, then water use will continue to be double the rate of population growth. During the 20th Century, the global population tripled, while water use per capita increased by six times.

Ataturk Dam in Turkey.
© M. McEvoy/
Panos Pictures

Expanding agricultural and industrial development, the proliferation of large dams and urban sprawl have profoundly altered the hydrological cycle - the Earth's plumbing - sundering rivers, streams, floodplains and wetlands, in effect disconnecting them from their inter-linked ecology. This plundering of water resources through dams, diversions, drainage and development degrades freshwater habitat, contributing to the impoverishment of freshwater biodiversity and loss of species.

Wetlands are hardest hit

Wetlands - swamps, marshes, fens, bogs, estuaries and tidal flats - have been hardest hit. Globally, the world has lost half of its wetlands with most of the destruction having taken place over the past half century. In some areas of Europe, such as Germany and France, 80 per cent of all wetlands have been drained for agriculture or paved over for urban and industrial development. The United States has lost more than 50 per cent of its wetlands since colonial times, amounting to 247 million acres (100 million hectares). California alone has lost over 90 per cent of its wetlands to development and sprawl.

The loss of these productive ecosystems is doubly harmful to the environment. Wetlands not only store water and transport nutrients they act as natural pollution filters, soaking up and diluting harmful substances such as nitrogen and phosphorus from fertilizers, residues from pesticides such as DDT, heavy metals such as lead and cadmium and raw sewage from human settlements. Not only is there less water available for ecosystems, pollution from agriculture, industries and municipalities continues to increase, reducing the ability of freshwater systems to process and dilute it.

A former coastal wetland converted into
a salt-making flat near Bombay, India.
� Don Hinrichsen

The UN Food and Agriculture Organization (FAO) estimates that every year roughly 450 cubic kilometres of wastewater are discharged into rivers, lakes and coastal areas. To dilute and transport this amount of waste requires at least 6,000 cubic kilometers of clean water. If trends continue, FAO reckons that within 40 years the world's entire stable river flow will be needed to dilute and transport humanity's wastes.

Hotspot regions badly affected

There will be no "winners" in this war. The competition among people, water and wildlife continues to intensify as the world's population and water needs grow. This is already proving disastrous for many regions of the world renowned for their biodiversity.

Using criteria developed by biologist Norman Myers, Conservation International has identified 25 biodiversity hotspots around the world, regions that are home to an extremely high number of endemic species, but that also have only one-quarter or less of their primary vegetation intact. Of these hotspots, 10 of them are located in water-short regions - mostly in California, Mexico and Central America, the Caribbean, the Mediterranean Basin, southern Africa and southwestern China. Population pressures and overuse of resources, combined with critical water shortages, threaten to push these diverse and vital ecosystems over the brink.

In a number of cases, the point of no return has already been reached. China, which contains 22 per cent of the global population, is already experiencing serious water shortages, affecting people and wildlife. According to China's former Environment Minister, Qu Geping, China's freshwater supplies are capable of supporting no more than 650 million people - half its current population. To compensate for the tremendous shortfall, China over-mines its aquifers and over-uses surface water.

As a result, the country has decimated its freshwater ecosystems in the name of development. Even in the water-rich Yangtze River Basin, population pressures, over-use and pollution have degraded and destroyed riparian environments. The population within the Yangtze watershed - one of the longest rivers in Asia, winding 6,300 kilometers on its way to the Yellow Sea - is around 400 million, one-third of the total population of China. The population density is also high, averaging 200 people per square kilometer. As the river, sluggish with sediment and laced with agricultural, industrial and municipal wastes, nears its wide delta, population densities soar to over 350 people per square kilometer.

A polluted section of the Yangtze
� China Features

Yangtze fish catch halved

The tragic effects of the country's water profligacy can be seen in the desiccated remains of lakes on the Gianghan Plain. In 1950 this ecologically rich area supported over 1000 lakes. Within three decades, as dams and irrigation canals siphoned off tremendous amounts of water for agriculture, industry and expanding cities, no more than 300 were left. Studies carried out in the Yangtze's middle and lower reaches revealed that in natural lakes and wetlands still connected to the river, the number of fish species averages 100. In lakes and wetlands cut off and marooned from the river no more than 30 survive, a two-thirds drop in fish biodiversity.

Yangtze fisheries have suffered from assaults on the river's ecology. Three of the river's largest and most productive fisheries - the silver, bighead and grass carp - have dropped by half since the 1950s. Catches of other commercial species are also declining.

Mammals and reptiles have fared little better. The Yangtze's shrinking and polluted waters are home to the most endangered dolphin in the world - the Yangtze River dolphin, or Baiji, the largest of the freshwater dolphin species. There are only around 100 of these very rare dolphins left in the wild, but biologists predict it may be extinct in a decade. If there are any left within 10 years, their fate will be sealed when the massive Three Gorges Dam is completed in 2013.

The river is also home to the Chinese alligator. With only 800-1000 of these imperiled reptiles left - the majority limited to a small stretch near the river's swollen, silt-laden mouth - this species is unlikely to survive beyond another decade. It is being done in by reduced water flows, pollution and a loss of prey species (again due to massive water diversions and pollution).

Shrinking lakes in Kazakhstan

The worst desecration of an ecosystem on the planet is the nearly complete annihilation of the Aral Sea, located in Central Asia between Kazakhstan and Uzbekistan. As a direct result of the massive diversion of water from the sea's two feeder rivers - the Amu Darya and the Syr Darya - to irrigate cotton fields and rice paddies, the sea has contracted by half and lost three-quarters of its volume since 1960.

Stranded tanker at Aralsk on the
Aral Sea�s north shore in Kazakstan.
� Don Hinrichsen

Hardest hit has been the unique Tugay forests - dense thickets of small shrubs, grasses, sedges and reeds - that once covered 13,000 square kilometers around the fringes of the sea. By 1999, there were less than 1,000 square kilometers of this highly diverse ecosystem left, fragmented into small, isolated patches.

Loss of the region's biological productivity is tantamount to biocide. Habitat destruction has dramatically reduced the number of mammals that used to flourish around the Aral Sea: of the 173 species found in 1960, mostly in the deltas, only 38 remained in 1990. Though the ruined deltas still attract waterfowl and other wetland species, the number of migrants and nesting birds has been nearly halved - from 500 species to 280 in 1990.

Plant life has suffered even more. Forty years ago botanists had identified 1,200 species of flowering plants, including 29 endemic species. Today, the endemics have vanished. The number of plant species that can survive in a much harsher climate, on highly saline soils, is a fraction of the original number.

Most experts agree that the sea itself may very well disappear entirely within two decades. But the region's freshwater habitats and related communities of plants and animals have already been consigned to oblivion.

Africa's shrinking Lake Chad

Similarly, the surface area of Lake Chad, once the second largest lake in Africa, has shrunk to one-tenth of its former size - dropping from 25,000 square kilometers in 1960 to 2,000 square kilometers in 1990. Though more water has been flowing into the lake from its feeder rivers over the past decade, the lake is still in serious ecological trouble. Like the Aral Sea, massive water withdrawals from Lake Chad's watershed to feed irrigated agriculture have reduced the amount of water flowing into the lake to a trickle, especially during the dry season.

Moreover, the lake is wedged between four nations: populous Nigeria to the southwest, Niger occupying the northwest shore and Chad the north east, with Cameroon clinging to a small section of the south shore. Nigeria has the largest population in Africa, with 130 million inhabitants. Population growth rates in these countries average three percent a year, enough to double human numbers in one generation, and population growth around the lake is even higher than the national averages. People gravitate to this region. The lake and its feeder rivers are the only sources of surface water in this dry, increasingly desertified region.

The lake's fisheries have more or less collapsed from over-exploitation and loss of aquatic habitats as its wasters have been drained away. Though some 40 commercially valuable species remain, their populations are too small to be harvested in commercial quantities. Only one species remains in viable populations - the mudfish.

As the lake withered, it was unable to provide suitable habitat for a host of other species. All large carnivores, such as lions and leopards, have been exterminated by hunting and habitat loss. Other large animals such as the rhinoceros and hippopotamus are found in greatly reduced numbers in isolated, small populations. Bird life still thrives around the lake, but the variety and numbers of breeding pairs have dropped significantly compared to 40 years ago (see: Why Lake Chad is shrinking).

A 'blue revolution' needed

As these examples illustrate, the challenge for the world community is to launch a genuine "blue revolution" that will afford governments and communities the chance to manage water resources on a more sustainable basis for all users, not just exploit the resource with the aim of supplying ever rising demand. "We not only have to regulate supplies of freshwater better, we need to reduce the demand side of the equation," complains Swedish hydrologist Dr. Malin Falkenmark. "We need to ask how much water is available and how best can we use it, not how much do we need and where do we get it". Increasingly, where we get it from is at the expense of aquatic ecosystems.

If blindly meeting demand precipitated, in large measure, the world's current water crisis, reducing demand and matching supplies with end uses will help get us back on track to a more equitable water future for everyone. Good intentions are not enough. The water initiatives launched in the wake of the World Summit on Sustainable Development held in Johannesburg, South Africa are laudable. But not one of them tended to the water needs of ecosystems, only the water needs of human communities.

There is an important lesson here: just as animals cannot live disconnected from their habitats (except in zoos) neither can humanity live disconnected from the water cycle and the natural systems that have evolved to maintain it. It is not a matter of "either or" says Karin Krchnak. "We have no real choices here. Either we as a species live within the limits of the water cycle and utilize it rationally, or we could end up in constant competition with each other and with nature over remaining supplies. Ultimately, if nature loses, we lose."

The nightmarish scenarios envisioned for a water-starved not too distant future should be enough to compel action at all levels. The water needs of people and wildlife are inextricably bound together. Unfortunately, it will probably take more incidents like the one in northern Kenya before we learn to share water resources, balancing the needs of nature with the needs of humanity.

Don Hinrichsen is a Contributing Editor of this website.

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