NEW DELHI (AlertNet) - There's no escaping urban India's growth.

In the capital, hundreds of migrants arrive daily at railway and bus stations, densely populated slums burgeon at the seams and building complexes, shopping malls and industrial plants are sprouting up in every direction.

But as industrialisation takes effect and growing numbers of rural populations move to towns and cities like New Delhi, experts say the inability to provide clean and safe drinking water - especially to the urban poor - has reached crisis point.

"Higher demand for water, increased pollution by humans and industry and the mismanagement of water is most of all impacting the poorest people in the country's towns and cities," said Sushmita Sengupta of a Delhi-based think-tank, the Centre for Science and Environment (CSE).

"Cities are already water-stressed and with increasing urbanisation, we need to learn to stop wasting vital resources."

According to India's last census in 2001, around 286 million - 28 percent of population - live in towns and cities.

This is projected to reach around 575 million people in 2030, which will mean around 40 percent of India's total population will be urban.

Yet no major cities and towns have a 24x7 water supply. Most households receive water twice daily - in the morning and evening - with many middleclass families relying on water storage tanks.

Water cuts that last days are becoming increasingly common in the scorching summer months, and water protests and reports of violence over water scarcity are on the rise in urban centres.

SLUMMING IT

For over 40 million slum dwellers across India, many of whom cannot afford to pay for private tankers to supply water, the basic amenities of clean water and toilets remain elusive, say aid workers.

New Delhi is one of the fastest growing and most densely populated cities in India, with about 1,000 migrants arriving every day - most heading to slum colonies scattered around the city in search of a better life.

An estimated 4 million people live in slums - almost 30 percent of the capital's population.

Yet many have to defecate in the open and have no choice but to drink and bathe in contaminated water.

In southwest Delhi's Mangla Puri slums, women fill buckets up from the only two working pipes that serve the 2,000 residents of this over-crowded, densely populated colony.

They wait patiently as a tiny trickle passes through a plastic pipe into their containers. "We are tired of living like this," said Satinder Singh Raghav, a 25-year-old driver.

"The past four days, we didn't have any water and when we do get it, it is very little."

Residents - most of whom live in families of around six in tiny one-room cheek-by-jowl concrete units - say they cannot afford to buy water and resort to knocking on doors in the nearby affluent enclaves begging for the vital resource.

Sanitation standards in Mangla Puri are also poor. The two open water pipes sit alongside massive piles of rotting garbage and open drains filled with sewage, plastic and other rubbish. Piles of human waste from the few public toilets available are dumped out in the open less than 50 metres from the slum dwellings and there is an unbearable stench as pigs roll around in puddles of sewage.

Aid workers say poor sanitation contaminates scarce ground water.

"One of the reasons for contamination of groundwater is human waste which is percolating into the same water that people are drinking," said Indira Khurana, WaterAid's director of policy and partnerships.

Although access to clean drinking water has improved in many parts of the country, the World Bank estimates that 21 percent of communicable diseases in India are still related to unsafe water. Globally, unsafe water kills hundreds of thousands of people every year.

Poor drinking water and hygiene practices are resulting in mass cases of diarrhea across the country, which cause more than 1,600 deaths daily, the World Bank adds.

Experts say groundwater is also polluted with chemicals from industry and agriculture such as fertilisers, as well as high concentrations of fluoride and arsenic.

POLLUTION AND WASTAGE

Contamination is not limited to groundwater. Surface water sources like rivers, lakes and streams which supply many towns and cities are also severely contaminated.

Environmentalists say most of these water sources are turning into sewers where municipalities are dumping billions of tonnes of untreated sewage, not only killing vital water supplies but also threatening the lives of the poor who drink and bathe in the water.

New Delhi alone produces 3.6 billion tonnes of sewage every day but due to poor management less than half is effectively treated. The remaining untreated waste is dumped into the Yamuna river - which accounts for 86 percent of Delhi's water supply.

According to the Central Pollution Control Board, around 70 percent of the pollution in the Yamuna is human excrement. The rest is industrial effluents and agricultural run-off. Environmentalists say while India has over 300 sewage treatment plants, most are under-utilised and positioned too far from sewage drainage points.

Treated waste is often mixed with untreated sewage and thrown back into rivers. India's drainage system is decrepit and in serious need of repair, with more than half of the country's drains virtually redundant.

"There is a massive amount of wastage of water due to poor management... We need to focus on policies like rainwater harvesting as well as decentralising waste management," said CSE's Sengupta.

Environmentalists argue that climate change will exacerbate the water crisis as vital monsoon rains become erratic.

A July 2009 report by the Australian government warned that in the coming years, climate change could drastically weaken monsoon rains on the subcontinent, on which more than a billion people rely for agriculture and water supplies.

The government must invest more in infrastructure and management, experts add.

"The water demand (in India) will exceed supply by 40 percent by 2030 if it's just a business-as-usual scenario and if the government does not spend adequately on infrastructure," said Bharat Sharma of the International Water Management Institute.

"You have little incentive to use the water efficiently."

(Additional reporting by Matthias Williams)

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