The water transferred more than 1,400 kilometers by the South-to-North Water Diversion Project is expected to ease the pressure on pumping underground water, which has gone deeper due to overexploitation in recent years.
Beijing is also capping 4,216 dry wells to prevent pollution, the municipal water authority said. These wells can no longer provide water due to the fall in the level of the water table.
More than 3,000 of them have been filled with concrete or covered with iron plates and all of them will be finished in 2015, said Wang Wei, deputy director of the water resources bureau of the Beijing Water Authority.
“The capping of wells will cut the channels of sewage and waste polluting the underground water and reduce the pollution risk to the major water sources and protect the drinking water supply,” he said.
In Beijing, more than 60 percent of the annual water consumption－3.6 billion cubic meters－comes from the underground water. The other 40 percent comes from rivers and reservoirs.
Underground water will continue to supply 50 percent of Beijing’s water when the diverted water arrives in Beijing, he added.
The level of the water table is around 24.5 meters and is 12.83 meters lower than what it was in 1998. The volume of water in the water table has decreased by 6.57 billion cubic meters, according to the Beijing Water Authority.
The South-to-North Water Diversion Project is expected to provide 1.05 billion cubic meters of water to the capital, and it should start to arrive by the end of December. It is expected that the diverted water will allow the water table to recover from the overexploitation and halt the fall in the level of the water table beneath the capital, said Sun Guosheng, director of the Beijing branch office for the project.
Beijing has conducted research on how to replenish the declining water table and the water authority has decided the best way is through the Chaobai River, a major river in the capital, said Meng Qingyi, vice-president of Beijing Water Science and Technology Institute.
“The water will replenish the vast funnel-shaped zone under capital that used to be part of the water table and then flow to neighboring areas, such as the Miyun, Huairou and Shunyi districts,” Meng said.
Based on the research, the replenishing of the underground water can be efficiently carried out in this region, he said.
The diverted water should satisfy the drinking water needs first and any surplus water can be stored in the Miyun Reservoir, he added.
Experts and government officials agree that water conservation should be a priority in the future.