More than 100,000 Baoshan residents are now drinking Yangtze River water after switching from underground water, the district's new supplier said yesterday.

The switch marked the completion of first-phase work to provide better water and to help control the use of underground water in the district to counter land subsidence, officials with Shanghai Waterworks Shibei Co said.

"It is to meet the demand for better water and to ensure sufficient supply," said company spokesman Li Chunhui.

Shibei has invested more than 63 million yuan (US$7.6 million) to lay 46 kilometers of pipe to carry water to the 100,000-plus residents. The supply will be 40,000 cubic meters daily.

Shibei's waterworks business was expanded when it took over the water supply for the whole Baoshan District on Tuesday. Its service area now nearly doubles its previous area at more than 600 square kilometers.

To cope with the expanded business, it has set up a new branch in Baoshan to manage all water facilities.

The 135,000 residents it serves are in the district's Dachang, Luodian, Yanghang and Gucun areas, where tap water from big water plants downtown was previously inaccessible. In the past, residents had to depend on small water plants using underground water from deep wells.

The underground water pumping in Baoshan accounted for about 30 percent of the city's total underground water consumption annually, officials said.

Residents complained for a long time about the taste of the underground water, saying it contained too much minerals.