As government officials hail the success of relocating 340,000 people in China's south-north water diversion project, they are also aware of the social and environmental challenges the project may bring.

The relocation in central China's provinces of Hubei and Henan is part of the project to transfer clear water from the Han River, a major tributary of the Yangtze River, to the drought-prone north, including the capital city of Beijing.

At the start of the route, the height of the Danjiangkou Dam on the Han River has been raised, and the reservoir behind the dam will begin to rise in 2014 so that water will flow all the way to the north.

Forced to leave home

The project forced 180,000 people in Hubei and 160,000 in Henan to leave their homes around the reservoir.

It is China's second-largest relocation program after the Three Gorges project, which involved the relocation of 1.27 million people over 17 years.

The immigrants, mostly poor farmers, have moved to more than 600 government-designed villages across the two provinces within the past three years.

Last Tuesday, the Hubei provincial government said that the relocation is a miracle in the history of reservoir immigration in China.

Tens of thousands of officials were employed in the relocation program. Among them, 21 died from fatigue and illness caused by constant work.

However, the relocation is just the first step of the immigration, said E Jingping, director of the South-North Water Diversion Office of the State Council, China's cabinet. "The goal for the coming years is to keep the immigrants stable, enable them to prosper and become rich."

However, discontent exists among immigrants who have found life harder in the new locations, where locals have different dialects and cultures. Added to this, living costs are higher with some houses being defective. Some immigrants are given low-grade farmland to work and those who grew fruits in hilly regions do not know how to grow rice on a plain.

Living standards are likely to go down for more than a third of the immigrants, Peng Chengbo, vice director of the Hubei Reservoir Immigration Bureau, told Xinhua.

Thousands of immigrants have traveled back to their hometowns to seek redress from governments. Some have barricaded highways, besieged government buildings and beaten migration officials.

Peng said that local governments were under pressure in maintaining stability in Hubei, where various water projects, including the Three Gorges and the water diversion, forced a total of three million people to move over the past five decades.

Hubei plans to help migrants to raise their living standards to average levels in the new locations within three years, and to surpass the average in another two years, Peng said.

Biggest challenge

The biggest challenge the 201.3 billion-yuan (US$38.1 billion) project faces may not only be resettlement but also protection of water resources and calls for compensation from affected downstream areas.

Beginning in 2014, the project will draw 9.5 billion cubic meters of water from the Han River annually.

When the second phase is completed, 12 to 14 billion cubic meters of water will flow north each year.

Critics warned that since 25 to 30 percent of the river's flow is taken away, the ecology of the middle and lower reaches of the Han River - a 650-kilometer-long section in Hubei - will be damaged and new water shortages will be created.

Hubei provincial environmental authorities cite a host of problems.

The river level will fall and the cost of using water for daily life and irrigation will increase. The river's ability to cleanse itself will decline and pollution control will become more difficult. The number of days when the river is navigable will decrease and water transport will be less efficient. Fish will suffer loss of breeding grounds. Decrease in water temperature will be harmful.

To make matters worse, Shaanxi province, which is in the upper reaches of the Han River, will begin constructing a project to convey 1.5 billion cubic meters of water annually from the river to supplement the Wei River, the largest tributary of the Yellow River.

This project aims to ease water shortages in major cities including Xi'an and Xianyang in west China, but it is feared it will exacerbate the situation in Hubei, where the Han River is crucial to 12 million people and needed to irrigate 1.13 million hectares of farmland known as the Jianghan Plain.

As a result, a 10-billion-yuan package of minor projects have been formulated to reduce the impact of the water diversion projects on the Han River. The most prominent is a 67-kilometer-long manmade canal to use water of the Yangtze River to make up for the loss in its tributary.

Robbing Peter to pay Paul

Ironically however, the scheme is said by some to be another case of "robbing Peter to pay Paul" and new problems are predicted.

The Han River will be polluted by water from the Yangtze River, the aquatic life population in the tributary will be further decimated with a decrease in water temperature, and the Yangtze River itself is short of water every winter, according to the Hubei Bureau of the South-North Water Diversion Project, which oversees the construction of the projects.

In addition, dams are being built to raise water levels near major industrial cities in Hubei, including Xiangyang and Qianjiang, to improve shipping and irrigation.

But experts say that with too many dams the river will be cut into a string of reservoirs holding large volumes of municipal sewage. Solving all these problems needs more investment and proper management, they said.

Mei Jie, author of "The Mighty River Goes North," who was born in the Danjiangkou Reservoir area, said, "I feel I have to tell the world about the suffering of the people in the south and that the water flowing north is not ordinary water, but the blood and tears of the people in the south."

The water diversion project is a must for the country considering the chronic water scarcity in Beijing, but the capital city is still expanding and many people there are not fully aware of how scarce water is and they really need to cherish it, she said.