The eastern region of Syria, where the ancient local Inezi tribe once reared camels in the sandswept lands north of the Euphrates river, is now reeling under severe water shortage.

Drought in the past five years has also killed 85 per cent of livestock in eastern Syria, the Inezis' ancestral land. Up to half a million people have left the region in one of Syria's largest internal migrations since France and Britain carved the country out of the Ottoman Empire in 1920.

Illegal wells to irrigate subsidised wheat and cotton have contributed to the destruction of the water table. Farms dependent on rain have turned into parched land. Diseases, such as wheat rust, have further devastated crops this season.

In the past decade rainfall has become scarcer, official data shows, shrinking to an average 152 mm from 163 in the 1990s and 189 in the 1980s. An unprecedented heat wave struck this year. Temperatures exceeded 40 degrees Celsius for 46 days in a row in July and August.

Syria has become a wheat importer, undermining a state policy of food self-sufficiency. While climate models project the region will become hotter and drier this century, ministers and residents say other factors are exacerbating the problem.

Environment Minister Kawkab al-Dayeh told a water conference in Damascus last month pollution had played a role in the deterioration of 59 percent of total agricultural land, with raw sewage being widely used for irrigation.

Residents say corruption and mismanagement are the main reasons for the crisis. They cite badly run state-controlled estates, a legacy of Soviet-style policies, and irrigation canals dug to reach well-connected landowners in the naturally more fertile lands to the west.

"Jub Shaeer is only 3 km from the canal, but look how dry the land is in the village," said Ahmad al-Mehbash, head of the state-backed Peasants Union in Raqqa province.

The state launched irrigation schemes for the east in the 1970s and boosted subsidies to grow wheat and cotton, attracting tribal support for the rule of the Baath Party, which took power almost 50 years ago and still enforces emergency law.

But the Soviet-built irrigation system has failed to keep up with a population boom in the past three decades. Syria's population of 20 million is growing 2.5 per cent a year.

Raqqa, the provincial capital founded by Alexander the Great, has been in perpetual decline.

Its horseshoe-shaped wall and museum housed in a French Mandate palace gives a glimpse of the magnificent city that once acted as a Byzantine front line against Persia and was later designated by Al-Mansour, the founder of Baghdad and the Abbasid caliphate, as the second Arab capital after Baghdad.

Just outside the city is the tribal stronghold of Jub Shaeer. The Euphrates river runs brown with sewage. Plots of land are black from salinisation, as if doused in oil. Boll worms have devastated the cotton crop.

Occasional olive and citrus trees pop up in the arid landscape at estates whose owners operate illegal wells.

Officials hint at the need to reform farm subsidies, blamed by independent economists and water experts for wreaking havoc on the environment and diminishing water resources.

Subsidies on fertilisers have been abolished, helping to lessen corruption, the agriculture minister said. Agriculture's share of gross domestic product has fallen 10 percentage points to 13 percent in the past five years, official figures show. It still consumes 90-95 per cent of Syria's water.

Tribal links with Saudi Arabia have helped the Inezis cope with the drought better than their compatriots in the east, who now live in slums around Damascus, Aleppo and Hama.

Women and children predominate in the concrete settlement of Jub Shaeer. The men are either in Saudi Arabia or trying to get there in search of menial jobs. Illiteracy and poverty are rife and government services are poor or non-existent.

Mariam al-Falaj is raising five children alone. Her husband found work as a shepherd in Saudi Arabia after his own flock died. "One of the children is without vaccinations because government health officials have stopped coming," Falaj said.

Social tensions are rising. Tribesmen gather daily at the house of their chief, Ghazi al-Muheimes, to air their plight. They ask for state jobs or for help to work in Saudi Arabia.

One shepherd makes 6,000 ($130) Syrian pounds a month and has a wife and three children to feed.

"He needs 2,000 pounds a month alone to buy bread. Imagine a life where the aspiration of a young man is to toil from dawn to dusk under the burning Saudi sun. If there was water, the men would till their own land and stay here," Muheimes said.

The government has set up a "drought resistance" division but its head in Raqqa province told Reuters his main task so far had been to collect data. International donors have been more active.

The World Food Programme is helping to feed 190,000 people, with another 110,000 needing rations. The United Nations estimates 800,000 of the eastern region's 5 million people live in extreme poverty.

Hekmat Jolaq, a government agricultural engineer, acknowledged that scaling back subsidies would help improve water availability, but said national security required Syria to maintain its policy of self-sufficiency in major crops.

Jolaq, who is also deputy head of the Raqqa Agricultural Engineers Union, said the solution lay in more investment, the streamlining of irrigation plans and adoption of technology. "China has managed to cover whole desert areas with newly developed grazing plants," he noted.-Reuters