Residents of Jiangxi province have been providing the city with clean water for more than half a century. Dara Wang reports. 

Xie Yujie stood looking over the land that was home to his ancestors for 350 years. The 65-year-old has often returned to this spot in the decade or so since he and his neighbors were relocated to safeguard the purity of the Dongjiang River, which supplies up to 80 percent of Hong Kong's fresh water.

Xie's ancestral home lay near Yajibo Mountain, the source of the Dongjiang, which spans three counties in Jiangxi province－Huichang, Anyuan and Xunwu.

Xie lived in Qingfeng, a village in Huichang blessed with fertile land. He recalled the villagers planting rice and raising poultry on the lowlands and growing mushrooms high on the mountain's slopes.

The decision to clear the village was taken because local farming practices threatened the purity of the water.

Xie Yuncai, Party secretary of the village, said excrement from chickens and other poultry leached into the soil and contaminated the river water.

Moreover, when the farmers planted mushrooms, they cut chunks of wood from living trees then bored holes in the harvested wood and planted mycelium spores.

As a result, the trees began to die, and the savaging of the local forests gradually reduced their capacity to conserve water.

According to Xie Yuncai, the removal order, issued in 2006, was intended to ensure clean drinking water for Hong Kong, which meant the villagers had to move.

Liu Chaohua, Party secretary of Qingxi township, said each villager was given 3,500 yuan ($517) to build a new house in the center of the township.

Some residents, such as Xie Jiawan, were unhappy with the development because they felt the settlement was unfair.

The Songwuchang group, an administrative subdivision of the village that was home to Xie Yujie and Xie Yuncai, was the only one of five groups in Qingfeng that was ordered to vacate the land because their presence had a direct influence on the source of the river.

"Our whole family had lived on the farmland for generations. How can we farmers earn a livelihood without land?" Xie Jiawan said.

As a venerable elder, Xie Yujie, who served as the village Party secretary for 16 years from 1983, was one of the first residents to leave. He wanted to set a good example to other residents, so in 2007 he demolished his ancestral home and moved to the center of Qingxi.

"To be honest, I was reluctant to leave the mountain," he said. "But I had to leave to preserve the purity of the water for the people in Hong Kong."

Xie Yujie and local officials spent several months persuading Xie Jiawan to move, and eventually he agreed.

By 2013, about 100 people from the Songwuchang group had relocated. Many other villagers have since followed, and the process is ongoing.