India has the world's highest number of people without access to clean water, imposing a major financial burden for some of the country's poorest people.

According to the Water Aid, an international charity that strives to improve access to safe water, as well as hygiene and sanitation, there are 75.8 million people in India (that's 5% of the country's population) who are forced to either spend an average of 72¢to buy 50 litres of water a day, nearly 20% of their daily income, or use supplies that are contaminated with sewage and chemicals. The people of Britain spend around 10¢ a day for the same amount.

Many people are forced to turn to an alternative in order to access water, due to the price or simply the issue of accessibility, but using dirty water comes with consequences and causes countless illnesses each year. There are about 315,000 children who die from diarrhoeal diseases each year, 140,000 of which occur in India. The much smaller countries of Papua New Guinea, Equatorial Guinea, Angola, Chad and Mozambique have also topped the list of areas with the highest population percentages lacking clean water. In Papua New Guinea, there are 4.5 million without access.

"Poor management of water resources is the biggest problem holding India back," the report said. "Misappropriation in planning and execution of water supply projects is another key factor. And projects often use inadequate sources, or pipelines do not reach habitations."

India already faces chronic water shortages and drought, as rivers become increasingly polluted and groundwater reserves rapidly decline thanks to the unchecked use of water pumps by farmers and villagers. The problem is set to worsen as global temperatures rise and rain becomes more erratic with climate change. Within 15 years, the country is expected to have only half the water it needs to meet competing demands from cities, agriculture and industry.

Drought-prone areas such as New Delhi and Rajasthan are bring water kiosks into place, while others such as Nagpur, are experimenting with privatisation schemes in order too improve service. Punjab, which produces the vast majority of India's grains, has set up public water filtration units in order to clean groundwater contaminated by sewage and agricultural chemicals, including pesticides and fertilisers. Experts worry the water crisis could exacerbate community conflicts or regional tensions, and have urged authorities to impose strict regulations on water pumping and water use.

"We don't handle public goods well," said environmental economist Pavan Sukhdev. "You need public management systems to manage public goods, and there are no market lessons to help guide that management."

India's Supreme Court "has already held that the fundamental right to clean water is a right to life," said court advocate Satya Tripathi, adding that it's only a matter of time before the issue comes back before the court. "The government really has to pay attention. Water is the one thing that can tear this country apart."