The monsoon is late and years of poor rainfall have left the city's water reserves almost exhausted. Bhopal bills itself as the City of Lakes (it has two large man-made lakes in the heart of the city and six smaller ones) but, in the first week of July, they have all but dried up; the largest of the man-made pools, the 1,000-year-old Upper Lake, has shrunk from 38 square kilometres to a mere five square kilometres. The last time it was full was in 2005.

The government's meteorological officials try to put on a brave face, claiming it is not yet too late for the rains to come, but the truth is Bhopal has received little more than a third of the rain it should have had by this point and the United States agri-culture department has warned the country could face a serious drought unless rain arrives soon. To make matters worse, there are growing concerns that the monsoon could be further hampered by a developing El Nino weather system. (The weather was to break, on July 8, when 62mm of rain fell on the city - but this enlarged Upper Lake by only a fraction.)

In Pushpa Nagar, the last few drops of water dribble out of the tap. The crowd has filled every-thing it can lay its hands on; old cooking oil con-tainers are the most popular choice, followed by metal pots, even old paint tubs are pressed into service. It's all over in less than 10 minutes.

With the falling water table leaving many of the city's bore wells dry, at least 100,000 people have become dependent for their water supply on the fleet of tankers that shuttle backwards and forwards across the city, carrying 6,000 litres at a time. Fights often break out among those waiting for a delivery and some tankers have to have a police escort; desperate residents have refused to allow them to continue their rounds until they have disgorged every drop.

In the Durga Dham slum, the tanker stops about 100 metres away from a giant water tower built to supply a more upmarket area nearby. The door at the foot of the spiral staircase leading to the top of the concrete structure is heavily padlocked to prevent those who live in its shadow getting to the water inside, although the indicator on the side suggests there is precious little left anyway.

Chand Miya, the local committee chairman, watches the women as they work feverishly to drain the tanker. There is simply not enough water to go around, he says. 'During the last five or six years it has been raining much less,' he says. 'The population has increased but the water supply [has not].'

A family needs about 100 litres a day for drink-ing, cooking and washing, he says, and people have no idea when the tanker will come again.

The flooding that inevitably accompanies the arrival of the monsoon may seem to suggest India's problem is too much water. Too often, though, the opposite is the case. This year the country experienced its driest June in 83 years.

Overpopulation and climate change have played their part, with many people abandoning agriculture because of the increasingly erratic rainfall and drifting into the cities, placing additional pressure on already stretched urban water supplies.

Last October, those of the 1.8 million people living in Bhopal who are fortunate to have a mains supply were restricted to 30 minutes of water every other day in an attempt to stretch the reserves. When the monsoon failed to arrive on time, that became one day in three. Those living in the nearby city of Indore had to manage with half an hour's supply every seven days.

As those with no access to a regular supply grew more and more desperate, neighbour turned on neighbour to fight for what little water remained. A tragedy became almost inevitable and on May 13, it happened. The pipeline running through Bhopal's Sanjay Nagar slum had been dry for days. The water in the pipe was not intended for the Malviya family. Nor was it intended for their killers; the people of Sanjay Nagar had simply worked out where the pipe ran and dug down until they hit it, determined to get what they regarded as their fair share.

The Malviyas' neighbours clustered round a hole in the street outside their house. It had been covered with a large red stone. There were other holes outside other houses, into which the residents pushed rubber pipes when the water started to flow.

It was just after 8pm when the water began to flow, says Sunita, a female relative minding the house. Raju Malviya, his father, Jeevan, and his mother, Gyarasi, rushed out into the street and started to fill their containers from the hole they had drilled in the pipe where it ran past the blue metal door of their house. It was not long before a mob formed.

A local tough guy, Dinu, was convinced that they had stuffed a plastic bag into the pipe to stop the water flowing further down the hill, the neighbours say. Dinu slapped Gyarasi and Raju tried to stop him. Matters quickly got out of hand.

'We were too afraid to do anything,' says one woman, who gives her name as Shanno. 'I don't think they were really trying to block the pipe but Dinu didn't want them to take any water. He just wanted it for himself.'

Harsh words were exchanged, then blows. Someone produced a sword and a few minutes later, the three Malviyas lay dying in the dirt. Their neighbours waited until the attackers had left, too scared to intervene, then filled their own containers until the water stopped flowing. The Malviyas were a pleasant family, they said later, but they didn't have much choice over their priorities; no one knew when the water would be switched on again. Everyone went back into their houses and locked the doors. A little while later the police arrived and took the bodies away.

'It is a terrible thing, that people should be fighting over water,' Shanno says, looking down at the dry hole in the ground.

The couple had four other children, who have gone to stay with relatives while the family wrangles over compensation from the authorities. The Malviyas are not the only ones to have lost their lives in India this year for the sake of a few litres of water. In Bhopal alone at least two other people have been killed while trying to secure supplies.

At least those whose neighbourhoods are served by tankers know that supplies will come eventually, even if they cannot be sure when. But, in addition to the city's 380 registered slums, there are numerous shanties where people have to fend for themselves. Some, like the Malviyas, tap into the main supply. Others cluster around the ventilation valves of the main pipelines, which stick up out of the ground, trying to catch the small amounts of water leaking out.

In the Balveer Nagar slum, a ramshackle collection of buildings rising up a hill above a wide drain, 250 families have no supply at all. The women get up in the middle of the night to walk the two kilometres to the nearest pumping station, where someone has removed some bricks to allow a steady flow of water to pour out. Below the giant pipe running from the pump house out across a small valley, women wash clothes on the rocks and men in shorts lather themselves before jostling their way forward until they are standing below the cooling stream of water to rinse themselves off.

Sumitra Prajati, 29, and 10-year-old Reena Dhani push their way through the crowd to fill up containers, balance them on their heads and set off back towards the slum. They must make the trip several times every day to have enough for their most basic needs. Sometimes the men stop them getting to the water, Dhani says, because they want to wash.

Back on the hillside, Reeta Adivaasi, 25, is preparing to set off again to fill up her containers, carrying her four-month-old daughter, Khushi, with her. She shuttles backwards and forwards, from 8am to 6pm, trying to keep her family supplied. Each trip takes an hour, she says, and she must make three or four trips every day to get enough water.

'If someone mends it, we won't have anywhere else to get our water,' says Adivaasi. 'This is the government's fault. We go to the corporation's offices to ask for help but no one listens to us. They are not interested.'

A few communities have received help from non-governmental organisations. In the Arjun Nagar slum, international charity WaterAid and its local partners have drilled a 115-metre-deep bore well, which provides water for 100 families, who each pay 40 rupees (HK$6.50) a month. Until the well was drilled, Shaheen Anjum, a mother of four, would get up at 2.30am every day to fetch water, wheeling a bicycle with five or six containers strapped to it to the nearest public pipe in the hope of beating the queues.

'Often we would get there and the water would not be running. It was so tiring and in the afternoon we would sleep. The children were suffering and getting ill because they had to come too,' she says. 'The tankers used to come but there were so many fights that the driver used to run away. The police used to have to come because there was so much fighting. We are lucky that there is water at this depth because in other places they have drilled and there is no water there.'

Even with the well, there is not enough water for everything. They still use a nearby pond to wash their clothes but at least now the women can bathe at home.

'Before this we used to have to plan our lives around water,' says Sarabjeet Kaur, one of the younger women standing around the pump. 'We could only wash twice a week and there were often arguments among the family because someone had used all the water. Now the water is here we can decide for ourselves when we wash.'

WaterAid is working in 17 of the city's slums, providing water and sanitation.

'It's not just Bhopal. This has been a drought year for many districts,' says Suresh Chandra Jaiswal, a WaterAid technical officer. 'Now it has reached a critical stage. We just don't know any more how long the water will last.'

In a good year, Bhopal may get 1,100mm of rain, mostly between July and September, but last year, it was 700mm. According to the meteorological department, this year's monsoon was expected to deliver only 93 per cent of the normal rainfall.

It is not just the water supply that is affected: 25 per cent of India's electricity comes from hydroelectric plants and there have been power cuts across the country, with outages of up to 10 hours a day in the capital, New Delhi.

Although the government has ambitious plans to divert water to Bhopal from the Narmada river, 70 kilometres away, that will not supply nearly enough to make up the shortfall.

The United Nations has been warning for many years that water shortages will become one of the world's most pressing problems in coming decades, with as many as four billion people estimated to be affected by 2050, according to one report.

Competition for dwindling water supplies has already raised tensions internationally. India and Pakistan are at odds over water supplies from the disputed state of Jammu and Kashmir while there is friction between the mainland and India over Beijing's plans to divert the Brahmaputra river. The Palestinians accuse Israel of denying them water and, in 1998, Turkey's plans to dam the Euphrates river brought it to the brink of war with Syria.

With temperatures at the start of July soaring to as high as 49 degrees in some parts of India and dozens of people reported dead from the effects of the heat, Indian scientists began experimenting with 'cloud-seeding' - using chemicals to trigger precipitation - in the hope of finding a way to outwit nature. But the real problem is that India has too many people in places where there is simply not enough water.

AT the EDGE of Upper Lake, the true scale of the disaster that has befallen Bhopal is clear. A steady stream of people heads out towards what was once an island, crossing a large expanse of sun-baked black silt that once formed the lake bed. The boat club is struggling - it has dragged the boats down to what is now the shore but trade is slow.

At a pumping station, the inlet pipe sits high and dry about 100 metres from the water's edge. No water has been pumped since January. That month, people started to volunteer to help de-silt the lake to increase its storage capacity but the problem of too little water remains.

A few men are working to dig a deeper channel so that when the rains come, some of it will be diverted to the pump. Employee Anwar Khan watches them dig half-heartedly. He gestures to railings on a wall that rises six metres above the dried-up lake bed. 'The water used to come up to here,' he says. 'Until February, it still reached the bottom of the wall. Look at it now.'

A water treatment plant at the end of the lake used to supply 100 per cent of the city's needs: now it can manage barely 20 per cent. Narmada Prasad, the supervisor, says demand has risen threefold since he started working here in 1983.

'There is just not enough water, even if the lake were full,' he says. 'Only rain can help. There is no other way out.'

Back at the pumping station, Khan, who has worked here since 1972, mops his brow as the sun beats down. He looks out towards the lake. 'I've never seen anything like this in my life,' he says. 'If there is no rain, there will be no lake. And if there is no lake, where will we get the water from?'