In the past, the Communist Party has reflexively turned to engineering projects to address water problems, and now it is reaching back to one of Mao’s unrealized plans: the $62 billion South-to-North Water Transfer Project to funnel more than 12 trillion gallons northward every year along three routes from the Yangtze River basin, where water is more abundant. The project, if fully built, would be completed in 2050. The eastern and central lines are already under construction; the western line, the most disputed because of environmental concerns, remains in the planning stages.

The North China Plain undoubtedly needs any water it can get. An economic powerhouse with more than 200 million people, it has limited rainfall and depends on groundwater for 60 percent of its supply. Other countries, like Yemen, India, Mexico and the United States, have aquifers that are being drained to dangerously low levels. But scientists say those below the North China Plain may be drained within 30 years.

“There’s no uncertainty,” said Richard Evans, a hydrologist who has worked in China for two decades and has served as a consultant to the World Bank and China’s Ministry of Water Resources. “The rate of decline is very clear, very well documented. They will run out of groundwater if the current rate continues.”

Outside Shijiazhuang, construction crews are working on the transfer project’s central line, which will provide the city with infusions of water on the way to the final destination, Beijing. For many of the engineers and workers, the job carries a patriotic gloss.

Yet while many scientists agree that the project will provide an important influx of water, they also say it will not be a cure-all. No one knows how much clean water the project will deliver; pollution problems are already arising on the eastern line. Cities and industry will be the beneficiaries of the new water, but the impact on farming is limited. Water deficits are expected to remain.

“Many people are asking the question: What can they do?” said Zheng Chunmiao, a leading international groundwater expert. “They just cannot continue with current practices. They have to find a way to bring the problem under control.”

A Drying Region

On a drizzly, polluted morning last April, Wang Baosheng steered his Chinese-made sport utility vehicle out of a shopping center on the west side of Beijing for a three-hour southbound commute that became a tour of the water crisis on the North China Plain.