Children in the village had their education cut short because they had to work to make up for the lost income at home. Without basic sanitation infrastructure, water sources were often contaminated and waterborne diseases were rampant.

In March last year, Green Cross International, a Geneva-based environmental and humanitarian non-profit organisation founded by former Soviet leader Mikhail Gorbachev, offered a helping hand. Working with Singaporean non-profit organisation Lien Aid and the Yunnan Environment Development Institute, Green Cross built new infrastructure for the secure supply of clean water and sanitation.

"Using pipes, we captured the water of a spring that was running down the mountain and supplied households and the local boarding school with safe water. We built showers, taps and latrines," says Marie-Laure Vercambre, director of Green Cross' Water for Life and Peace programme.

The six-month, 500,000 yuan (HK$630,000) project was co-funded by the local government, Lien Aid and Green Cross, says Lien Aid's CEO, Koh Lian Hock.

"Apart from hardware, we also provided software: we educated the villagers about good hygiene practices and how to make use of the new facilities to improve their health," Koh said.

Heinigou is the first village in China to benefit from Green Cross' Smart Water for Green Schools programme, which was launched in 2010 to provide access to safe drinking water. The initiative has so far benefited more than 52,000 people within about 70 communities in Argentina, Bolivia, China, Ghana, Ivory Coast and Ukraine.

The Heinigou project also marked Green Cross' first foray into China in its 20-year history. As the organisation celebrated its anniversary this month in Geneva, its president, Alexander Likhotal, said the goal was to do more in the region. "Our pilot project is tiny, but it's an extremely important avenue of activity for Green Cross," says Likhotal, who was Gorbachev's adviser and spokesman. "We do hope that since we've started, we'll be able to show the authorities that we're there to help the Chinese people resolve the problems that exist."

China is facing a water crisis. Freshwater resources per head amount to about 2,200 cubic metres, less than a third of the global average. The government has warned that it will have exploited all its available water supplies by 2030.

China's population is predicted to peak at 1.4 billion in 2025. Accompanied by rapid economic growth and increased consumption of animal products, the strain on freshwater resources is growing. According to UN figures, it takes about 3,500 litres of water to produce 1kg of rice, but 15,000 litres to produce 1kg of beef. Freshwater supplies in China are further diminished by widespread water pollution from growing industrial development, according to a recent report in led by researchers from the Chinese University of Hong Kong's State Key Laboratory of Agrobiotechnology and School of Life Sciences.

Extreme weather, such as droughts and floods, is not helping. Water scarcity is especially severe in the northwest, which comprises more than 40 per cent of China's total land area and has undergone widespread desertification, the researchers said.

A major source of disease in China is the shortage of clean water and poor sanitation, they added. In rural areas, an estimated one-third of the population does not have access to improved sanitation. Vercambre said about 120 million people in China do not have access to safe drinking water.

On July 1 last year, China's new national standards for drinking water quality officially took effect; they include more than 100 items from the WHO guidelines.

"This is the first time a developing country has implemented strict regulations on drinking-water quality, and, in China, the first time the same standards have been applied in rural and urban areas," wrote Fudan University researchers recently in . "This is a milestone in Chinese environmental legislation, signalling a vigorous national effort to improve drinking water quality and public health."

While China's water challenges are unique because of their scale, Vercambre said "they're not unique in terms of the issues faced".

Indeed, water scarcity is a global problem with environmental, economic, social and humanitarian dimensions. The recent World Water Week and this year being the UN's International Year of Water Co-operation has brought particular focus to the crisis.

According to the UN, about 1.8 billion people worldwide lack access to safe drinking water. About a third of the world's population currently suffers from water stress, and the UN predicts this will rise to two-thirds by 2025.

From now until 2050, global water demand is expected to increase by 55 per cent, due to growing needs from manufacturing, electricity generation and households. Yet the world's water supply will remain the same.

"About 75 per cent of the planet is covered with water, but of this only three per cent is freshwater," says Vercambre. "Ten countries - and China is one of them - have on their territories 60 per cent of all this freshwater. That means the rest of the world, more than 180 countries, share the remaining 40 per cent."

Promoting access to and cooperation over water are therefore central to Green Cross' Water for Life and Peace Programme. That's why the Heinigou project has additional significance, Vercambre says. Yunnan is the first stop of the Mekong River Basin, which flows from the Tibetan Plateau through Myanmar, Laos, Thailand, Cambodia and Vietnam.

What happens upstream can have great impact downstream. For example, changes in water levels resulting from water use upstream can affect downstream agriculture. Pollution, meanwhile, flows downstream and respects no borders.

There are 276 cross-border watercourses in the world. According to Unesco, 145 nations have territory within a transboundary basin and 21 lie entirely within one. Over the last 50 years there have been 1,831 incidents on transboundary basins - both conflictual and co-operative. Seven disputes have involved violence, while about 200 treaties have been signed.

"Green Cross is advocating the equitable and sustainable use of shared water resources," says Vercambre. "For us, it's very clear that you need to deal with water issues at the local, regional and global level."

In 1997, the UN Watercourses Convention was launched. It is a global legal framework that establishes basic standards and rules for co-operation between watercourse states on the use, management, and protection of international watercourses. But it has still not come into force, with more states needed to back it.

China was one of three states, along with Turkey and Burundi, which voted against the convention in 1997, noting that states had "indisputable sovereignty over a watercourse which flowed through its territory".

However, according to a research report published in in April this year, China has signed border treaties with all of its neighbouring states except Bhutan and India, demonstrating its implicit support for some of the main norms of the convention.

According to Dr Patricia Wouters, Professor of International Water Law at Xiamen Law School, China's reaction to the convention has been to use international diplomacy, a so-called "soft path" of co-operation, which is the bedrock of China's foreign policy.

This approach, based on "dialogue, consultation and peaceful negotiations" has been expressed both by legal scholars and confirmed in foreign policy statements under China's new leadership under President Xi Jinping and Premier Li Keqiang . While it has many positive aspects, Wouters said the challenges for downstream states brought by the development activities of upstream states remained a "hard" problem, especially where the soft-path meets an impasse.

China has been very active in reaching out to its neighbouring countries and Wouters voiced hope that this would be reflected in increased co-operation on its transboundary water resources.