Hidden Waters, Dragons in the Deep: The Freshwater Crisis in China’s Karst Regions

Yunnan Province is a microcosm of the challenges facing China’s vulnerable freshwater supply. Severe water pollution and shortages stand in the way of ongoing economic growth.

In the southwest corner of China, a land of towering mountains and deep gorges not far from the border of Vietnam, is Shi Dong, the Rock Cave. It is here, 800 miles west of the Pacific Ocean, in an area so remote that people often settle in villages with no more than a few dozen homes, where the Yang Liu River disappears underground.
For more than 20 miles, the river flows beneath the surface of the earth, coursing through dark caverns and crevices in rocks, unseen and unknown to those who live above, its precise path a mystery. It emerges again through the mouth of a second cave, Nan Dong, the South Cave.

These two openings in the earth, where the Yang Liu River slips into and out of the shadows, mark the point where a fluvial region rich with surface streams meets an unusual geologic formation of soluble rock layers known as a karst landscape. It is also a fateful human dividing line, a place where China’s desperate confrontation with water scarcity, industrial modernization and pollution come into clear focus.

China’s vision of assuming a greater place on the world stage and prospering in the 21st century — goals it impressively displayed at the 2008 Summer Olympics and at other global events since — depends in large measure on its capacity to fit thriving human settlements into a severely damaged landscape where water is scarce, inaccessible, or often too dirty to use. More than 400 of China’s 600 largest cities experience water shortages, according to United Nations assessments. Three-quarters of China’s rivers and lakes are dangerously contaminated by municipal waste, as well as industrial and agricultural pollutants. The World Bank estimates that by 2020 water stresses in China could create up to 30 million environmental refugees, people who must move from their homes in search of one of the most basic necessities for life.

Just like the polluted waters of the Yangtze River, the eroded hills of the Loess Plateau and sandstorms whipped up in the deserts of Inner Mongolia that pummel Beijing every spring, the Shi Dong and Nan Dong caves of Yunnan Province represent the front lines of China’s fresh water crisis. Studies of China’s southwest karst region indicate the water beneath the surface is contaminated with bacteria, chemicals and sediments that drain off the land. Moreover, the region’s porous landscape makes securing a steady supply of water for agriculture and household use an often daily challenge.

The question that confronts the nearly 100 million people in Southwest China’s karst region, and 1.2 billion other Chinese citizens is this: Can the economic miracle that has lifted 450 million people out of poverty in a generation continue to advance when so much of the country’s natural treasury, especially its storehouse of fresh water, is so depleted?

East Mountain Plateau
At least a portion of the answer can be found in places like the East Mountain Plateau of Yunnan Province. On one side of the plateau, where the Yang Liu River rushes above ground in a narrow valley, people who live nearby can walk to its banks to get water. They can also dig wells, which at a certain depth will hit the water table. The land here is lush, with rice paddies tucked into mountain valleys.

But on the other side, the karst side, the water runs beneath their feet through a honeycomb of porous rock, in places more than a thousand feet below ground. People living on the surface of the karst formation have almost no way to reach the river. They cannot see it or discern its course. In some places the water is close enough to the surface for rudimentary wells to be drilled, though few would be successful because the shafts usually fail to strike the precise place where the water flows. In most other instances the water is too deep beneath the surface for wells to be drilled with the simple tools and resources available in this isolated region.

The consequences are clear. The people who live here, where the water runs beneath the earth, are among the poorest in China, earning an average of $80 annually, according to several studies. For much of the year, their fields are parched, their gardens dusty, and their hopes for a better life run dry.
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