It is often claimed that there is enough water on our globe for all foreseeable future purposes. Fresh-water resources could provide drinking, food and energy water for a larger world population.
However, water is not available in all the places and at all the times required. Collection, storage and distribution require large capital and running expenditures. Furthermore, to avoid pollution and disease, proper water supply must be accompanied by safe waste disposal, with equal priority for both.
It may be said that these are platitudes. But mankind, and armies in particular, took a long time to act on them. In the 1860s, 225,000 of the 393,000 American Civil War deaths were due to disease.
For various reasons many Third World countries lag behind with both water supply and waste disposal. Sometimes a look at their military expenditures will show why.
Since water is essential for life, efforts even to find it on the moon have been made. Without water, life will not continue, or so says the existing scientific wisdom.
The trans-boundary basins of the Great Lakes in North America and the North Eastern Congo, the rivers Rhine and Danube in Europe, the Amazon in South America, the Nile in Africa, the Tigris, Euphrates, Yarmuk and Jordan in the Middle East and the Mekong in Asia flow through many states (nine in the case of the Nile). Perhaps in these circumstances there are fewer disputes than might be expected.
River problems between the US and Mexico have long been settled by agreement, as have those between Mexico and Guatemala. Joint monitoring teams, which include engineers and technicians, solve any new difficulties.
Agreements were reached between South Africa and Lesotho about water development in the Orange river/Senqu Basin and between South Africa and Swaziland about the Kumati river.
The Ganges rises in China and flows through Nepal, India and Bangladesh. There have been disputes between India and Bangladesh, but considerable progress has been made towards peaceful settlement.
UN figures show that 50 countries have upwards of 75 per cent of their territory within multinational river basins. Upstream states can exert a stranglehold, so international agreements are obviously desirable. In some cases, however, they do not exist.
Reports about the Aswan High Dam on the Nile are conflicting. It has successfully controlled floods and droughts, but evaporation rates in the dam area, and from the great, slow-moving sheets of water behind it, are very high.
The Jonglai Canal scheme to drain the swamps and concentrate the river flow was halted in the Sudanese civil war. Silt, which previously would have provided cultivable soil, gets trapped behind the dam wall.
Egypt has many measures under way to improve and increase water supplies. Rising population is the spur. Seawater and brackish water have been desalinated and drainage and waste water are being used.
In some places all the obvious water resources have been developed. It is hard to see where the future water resources will come from for mega-cities with rapidly growing populations. The best dam sites have been used. Ground-water levels have dropped in Jakarta, Mexico City, the Po Valley and the Ogalla aquifer in the US.
Cairo, with nine million inhabitants, has Nile water but it fell behind on waste-water disposal. To catch up, US assistance, huge expenditure and years of work have been necessary.
There have been many predictions of "water wars" in the 1990s. They have not happened, yet. This is largely due to the military inability of the "have-nots" to challenge the "haves", even where water has been diverted or aquifer areas militarily occupied. Might is right in this vital matter. Negotiations and regional sharing plans, not wars, are needed.
Are "water wars" likely soon? Some writers argue that the problems are often internal rather than external. Wasteful use, poor distribution, perverse political priorities, inadequate expenditure, badly trained water engineers and technicians, and the assumption that water is a free gift from heaven can all cause shortages and pollution.
These arguments are self-serving when used by the "haves", especially when they are ignoring other peoples' rights. But our own experience shows how easily water is wasted, especially when it is free and plentiful. In countries with water meters, people are more careful. And some Third World irrigation practices are highly wasteful.
Turkey is building the vast South-East Anatolia Project (GAP). It will eventually include 21 dams and 17 hydroelectric plants on the Euphrates and Tigris rivers and their tributaries, in an area half the size of England. Downstream, these rivers flow through Iraq and Syria and are vital for agriculture.
The Turkish-Israeli alliance, even without US backing, constitutes a regional superpower. The GAP, "one of the seven wonders of the modern world", has given Turkey a vision of a pivotal role in Eurasia. Turkey has the geographical position and the military power. The GAP will provide the economic power.
Iraq is in a bad way and is getting worse under almost daily and unpublicised bombing. Control of the master water-taps will soon transform the politics and economics of the area. But Syria and Iraq may be pushed too far. Desperate men are dangerous, as Israel has discovered.
Turkey says it will continue water supply but that Syria and Iraq need to improve their utilisation and reduce waste.
For contrast we have the Gabcikovo problem in Slovakia. The communist governments of Hungary and Czechoslovakia signed an agreement in 1977 to build dams on the Danube. After the fall of communism, Hungary stopped working on the project. The Slovaks proceeded with a variant of the scheme. Hungary objected on environmental grounds.
However, both parties went to the International Court in The Hague in 1995, the first water case heard there. The court supported Slovakia on most counts because of the 1977 agreement but said Slovakia went too far on the variant scheme. Further negotiations were required. Both sides agreed in advance to accept the court's ruling. Legal procedures worked, albeit incompletely.
For this year's drought, Turkey supplied water to occupied northern Cyprus using huge towed bladders. Oil tankers are being considered.
Desalination plants can change salt water into fresh, or "sweet", water. Saudi Arabia has over 20 plants producing 30 per cent of all desalinated water in the world. Large amounts of energy are required, putting desalination beyond the means of poorer states. The Saudis are also pumping deep fossil water reserves. Critics call this "mining" because these reserves are not renewable.
Libya has the Great Man-Made River. Fossil water discovered under the central Libyan Desert is pumped through two buried pipelines as high as double-decker buses to supply the coastal towns. Again, the cost is high. The supply may last only 40 to 50 years.
There are environmental worries about dams, canals and deforestation. Clearances of animals, plant species and indigenous peoples distress scientists and conservators. Suppose those lost plants contain future cures for AIDS or cancer? Failure to consider the indigenous people is said to have been a reason for the attacks on the Jonglai Canal in Sudan.
The law of unexpected consequences from huge civil engineering schemes destroyed the Aral Sea in Soviet Russia. A vast plan to change the climate by diverting Siberian rivers southwards to parched Soviet Central Asia alarmed foreign and Soviet experts, because it could have made the Arctic Ocean more saline and caused even faster ice contraction than the "greenhouse effect". When Mr Gorbachev came to power the scheme was cancelled.
There are complex connections between overpopulation, deforestation, overgrazing, soil erosion and degradation, floods and droughts, water shortages and war. We think deforestation takes chain-saws and logging gangs. But large numbers of gentle peasant women gathering firewood daily can also help the process just as surely, if less quickly. We live in a complex world. Shortages need negotiation and forethought, not greed and war.