Now the depth of Beijing’s underground aquifers sinks deeper and deeper due to over-extraction. Data came from Beijing Tap Water Museum. “Over-pumping has largely depleted the shallow aquifer, forcing well-drillers to resort to the region’s deep aquifer,” the founder of Washington DC-based NGO Earth Policy Institute Lester Brown wrote in a 2001 article about the depletion of underground water sources in the North China Plain. “Anecdotal evidence suggests that deep wells [drilled] around Beijing now have to reach 1,000 meters to tap fresh water, adding dramatically to the cost of supply,” Brown continued, citing a World Bank report.