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Date Published: 22/06/00
Author: Ed Metcalfe The world is running out of water. Ed Metcalfe finds out why. |
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The scholars were perplexed. Reading and re-reading the accounts of the early Christian ascetics living in the desert around Antioch, they kept coming across the repeated use of the Greek word dunamis – power – to describe these fiery religious extremists. What could it mean? Power over what? Power to what? Supernatural causes were obviously ruled out, but the apparent lack of any rational political explanation was mystifying.
At last, a convincing theory was put forward and accepted by most scholars. The accepted suggestion was that the solitary nature of the desert ascetics made them the natural choice for an impartial arbitrator in local disputes. In particular, it was suggested that their deliberation in disputes over who controlled the scant supplies of desert water would have elevated the holy men to a position of considerable political power.
WATER AND POWER
Two thousand years on, and the power politics of the Levant still hinges on religious men and – more than ever before – water. Israel today treats water as a matter of national security. Two-thirds of the water it uses originates in territories it now controls through military conquest – the Golan Heights and the West Bank. The flow from the River Jordan is stored in the Sea of Galilee, from where it is carried to Israel’s cities, farms and industries, which would otherwise simply collapse. The headwaters of the Jordan are situated in the Golan Heights, occupied in 1967 by Israel. Who controls the Golan controls the water. Though Israel has promised to return the territory to Syria, she will not do so unless her water supply is secure. About one-quarter of Israel’s remaining water comes from aquifers (underground reservoirs) located inside the occupied West Bank – as good a reason as any for not handing the region back.
Israel’s control of the headwaters means that the tiny kingdom of Jordan is particularly vulnerable to Israel cutting off her water supply from the Jordan and Yamouk rivers. In 1990, King Hussein of Jordan commented that water was the sole reason Jordan might go to war with Israel. Under the 1994 peace treaty between the two countries, Israel agreed to provide Jordan with extra water and to co-operate in the face of acknowledged shortages. In 1999, however, the worst drought in 50 years forced Israel to unilaterally cut Jordan’s agreed supply by 60 per cent, forcing Jordan to drain its already depleted aquifers.
FIGHTING THE LAST DROP
As demand for water intensifies across the world, the prospect of conflict between nations over depleted supplies becomes very real. In 1999, for example, Libya’s Colonel Gaddafi warned that, ‘the next Middle East war would be over dwindling water supplies’. This was no novel prediction but rather an echo of the well-publicised statement made by the World Bank several years earlier that control of water would be the breeding ground for wars in the twenty-first century.
Israel’s control of the Jordan basin is not the only potential flashpoint. Across the world, conflicts over increasingly scarce water loom large on the horizon. For more than two decades, India and Bangladesh have quarrelled over rights to extract water from the Ganges during the dry season – and this seems set to worsen. Turkey’s Grand Anatolian Project, a vast irrigation and hydroelectric damming scheme on the Tigris and Euphrates, threatens to deprive Syria and Iraq downstream. Syria has ambitious irrigation plans of her own that would further hit Iraq. Egypt fears appropriation of the Nile’s waters – on which it is entirely dependent – by upstream Sudan and Ethiopia. The list is long and growing.
THE CAUSES
To be taken seriously, international water tensions need to be seen in the context of what is happening to the world’s water. This most basic of resources is facing a classic collision between supply and demand. Available fresh water represents less than half of 1 per cent of the world’s total water stock – the rest is sea water, or frozen in polar ice. While the world’s human population is increasing by roughly 85 million per year, the supply of continental rainfall – the only renewable source of fresh water – remains constant. Expanding cities and industrialisation are guzzling water at an astonishing rate. Worldwide, the consumption of water is doubling every 20 years, with industrial water use alone projected to double by 2025. As demand soars, increasing levels of pollution further restrict the use of available water.
A recent study conducted by the International Water Management Institute projects water supply and demand for 118 countries over the 1990-2025 period. The study predicts that 17 countries in the Middle East, including the warring neighbours Israel, Syria, Jordan and Egypt, as well as South Africa, Pakistan and the dryer regions of western and southern India and northern China will all face ‘absolute water scarcity’ by 2025. These regions, representing more than 1 billion people today (estimated to reach 1.8 billion in 2025) will not have enough water to maintain 1990 levels of per capita food production from irrigated agriculture and also meet industrial and household needs. They will accordingly be forced to reduce the amount of water used in irrigated agriculture and transfer it to urban and industrial sectors, importing more food instead.
This shift is already well under way in northern China, where swelling cities and industries are exerting their economic weight to draw water from the Yellow River at the expense of agriculture in the lower reaches of the basin. The study also points to 24 countries, mainly in sub-Saharan Africa, which face severe ‘economic water scarcity’ by 2025. These countries do have sufficient potential water resources to meet projected 2025 requirements. They will, however, have to double the amount of water extracted and diverted by that time to meet those needs. This will require massive water development projects, at enormous cost – which they can ill afford – and possibly severe environmental damage.
EXTRACTION
Although it is the world’s burgeoning cities and industries – particularly, in terms of growth rates, in the ballooning megacities of the ‘developing’ world – which pose the greatest challenge to the world’s water supply, agriculture remains the chief culprit for today’s predicament. Roughly 70 per cent (globally) of water diverted from rivers or drawn up from aquifers is used for irrigation. Irrigation is a hugely wasteful process. Leaking pipes, unlined channels, evaporation from reservoirs and canals and poorly directed spraying mean that 60-85 per cent of the water never reaches the plants’ roots. It is primarily irrigation that is responsible for the most serious problem that characterises the state of the world’s fresh water – the depletion of underground aquifers. Across the world, farmers are pumping groundwater faster than precipitation can replenish it, causing a steady drop in water tables; a process referred to by hydrologists as ‘groundwater overdrafting’.
The explosive spread of small pumpsets and groundwater wells throughout the world over the last several decades is largely to blame. India, for instance, has more land irrigated by pumps than by all the other surface irrigation systems combined. Extraction of water from aquifers in India exceeds recharge by a factor of two or more. The situation is particularly serious in the States of Punjab, Harayana, Maharashtra and Gujarat, where water tables are dropping 0.5 to 0.7 metres per year. Falling water tables cause farmers to compete with each other in the digging of ever deeper tubewells.
North China is running a chronic water deficit, extracting from aquifers some 30 billion cubic metres a year more water than is naturally recharged. Across the region, which produces 40 per cent of China’s grain, water tables are dropping on average 1.5 metres a year. Since 1965, the water table under Beijing has fallen by some 59 metres.
Much of North Africa and the Arabian Peninsula sits on huge ‘fossil aquifers’ left over from previous climatic eras. These aquifers receive little or no replenishment from current rainfall, so pumping from them, as with mining oil, means permanent depletion. At the current rate of extraction, Saudi Arabia’s grain irrigation programme will result in total depletion in the next 50 years. Libya has embarked on the most ambitious, and arguably senseless, project of all: mining the immense Nubian aquifer under the Sahara and piping the water 1,500 kilometres north to the coast to create new agricultural zones. Experts say the water will run dry in 30–50 years.
In the US, groundwater is being recklessly mined in California’s Central Valley and across the High Plains from West Texas to South Dakota where the mighty Ogallala aquifer, which alone waters one fifth of US irrigated land, is being depleted eight times faster than nature can recharge it.
Irrigation, of course, not only depletes groundwater but reduces surface flow too, with dams and diversions that cause downstream desertification and the loss of productive wetlands and freshwater fish stocks. China’s Yellow River, for instance, has run dry and failed to reach the sea every year since 1985. Excessive river diversions for irrigation have shrunk the Aral Sea by half, destroying almost all of its wetlands and fish.
Though irrigation causes water tables to drop, it can also have the opposite effect. Where the irrigation is intensive and the soil not well drained, waterlogging causes the water table to rise. The surface water then evaporates leaving an accumulation of salts that renders the land useless for cultivation. This problem afflicts a quarter of all irrigated land and is most acute in Pakistan, where two million hectares have been lost to high soil salinity.
EVERY DROP COUNTS
Clearly, swift and decisive action needs to be taken to address the world’s water problem. Reducing consumption is the first step, and improving irrigation efficiency– and waterlogging, where it occurs – is a key area where this can be achieved. Lining canals will reduce seepage, but it is ‘drip irrigation’ that has the most substantial untapped potential. Consisting of a network of perforated tubing laid on or below the soil surface that drips water directly onto the plants’ roots, the drip system, unlike a flooded or spray-irrigated field, loses barely any water to evaporation or misdirection. Studies have shown drip irrigation to cut water use by up to 70 per cent and increase crop yield by as much. Pioneered by the Israelis, drip irrigation accounts for only 1 percent of all irrigated land worldwide but its potential is enormous now that more affordable and practical systems have been developed.
Rainfall ‘harvesting’, through both new and traditional community-based methods can make a real difference to peoples’ lives in arid zones without plundering groundwater, and at almost no cost. Villages in the Jhabua district of Madhya Pradesh, for instance, have avoided the impact of the drought that has recently blighted much of Western India.
The water harvesting structures these communities have built meant they were well equipped to face the water scarcity, with enough for drinking and in some cases irrigation. Growing water-intensive crops like rice in water-stressed areas could also be abandoned in favour of crops such as cotton which need less.
In some cases, it might be possible to recharge aquifers by collecting precipitation during the rainy season in ponds or bunded fields – that would otherwise flow to the sea – and allow it to percolate down into the aquifer. It could even be pumped down, provided the water was clean.
This would work only where there is sufficient rainfall and the aquifers are accessible.
Human and industrial waste discharged into rivers, as well as agricultural runoff, also places a major restriction on the use that can be made of available fresh water. Ninety per cent of the ‘developing’ world’s waste water is discharged untreated into local rivers. In China, 80 per cent of the country’s major rivers are so degraded they no longer support any fish. Many Eastern European rivers run yellow with industrial poisons. The reuse of waste water for non-drinking purposes, however, provides huge scope for reducing the pollution that enters rivers, and saving water consumption by increasing its productivity. ‘Sewage farming’ in Israel reclaims 70 per cent of the country’s sewer water and uses it for irrigation. A project in the Himalayas diverts 6 million litres of sewage per day that would otherwise be dumped into the Ganges and uses it to raise fodder crops. Industries in America that have been diligently recycling their water since prices went up have made massive cuts in consumption.
WATER FROM BRINE
Desalination – making fresh from salty water – is for many hopefuls at least one technological solution to the impending crisis. The process is prohibitively expensive, conducted only in the wealthy countries of the Middle East, notably Saudi Arabia. The alternative for the Middle East, however, may be even more expensive. Figures have been compared (a desalination project for 100,000 people buys one jet fighter) and it’s agreed that war is the costlier option.
But who knows what hot and thirsty people will do? A scantily clad holy man from the desert might even intervene and, with one tap of his staff, equitably divide the waters.x
Ed Metcalfe is a freelance journalist specialising in environmental issues.
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