One of the most amazing things I saw during my October 2004 tour of western China was an ingenious 2,000-year-old irrigation system that still functions today, delivering water to grape vineyards and cotton fields.

The ancient karez irrigation system is located in China’s western-desert farming community of Turpan. Annual rainfall at Turpan is 16 millimeters (0.63 inches). Summertime temperatures are so hot that tour guides routinely impress tourists by frying an egg on a flat rock. Turpan lies in the second deepest inland depression in the world, with more than 4,000 square kilometers (1,544 sq. miles) of land situated below sea level.

Turpan was once one of the crossroads of central Asia – a strategic stop on the overland Silk Road trade route linking China with India, Persia, and Rome.

The karezes at Turpan are a series of vertical wells linked by underground channels that use gravity to move water from snow-capped mountain peaks to the desert floor. Putting the channels underground reduces water loss from seepage and evaporation. Each karez is fed entirely by gravity, thus eliminating the need for pumps.

Laborers dug thousands of karez wells and several thousand miles of 5 ft. x 5 ft. underground tunnels by hand using picks, shovels and buckets. The underground tunnels link the long rows of wells.

Well and tunnel digging began at the Turpan depression and proceeded up the contour of the hillsides towards melting glaciers at 16,000 feet elevation. Wells were spaced approximately 100 feet apart.

Only when water reaches the desert floor does it flow in above ground channels to storage ponds where it is distributed to individual farmers’ 820 ft. x 985 ft. grape vineyards. Because the ancient karez system was so effective, many more karezes were constructed in the 20th century and today there are over 1,000 karezes in the Turpan area.                   

With abundant sunshine, hot temperatures and limitless water, a bountiful grape crop is assured. Grapes are sold fresh in the street market as table grapes, dried into raisins, and processed into wine.

The average grape grower in Turpan earns approximately $2,000 (U.S.) income per year, considerably more than farmers in many other parts of China. Some Turpan farmers also grow cotton and melons.

In Turpan’s open-air city market, dozens of varieties of raisins are artistically displayed for purchase. I bought a two-pound plastic bag of light-green raisins and enjoyed them as snack food in the days that followed. They were delicious.

The karez irrigation system at Turpan is regarded as the third-most notable ancient achievement in China, after the 4,163-mile Great Wall of China and the 1,200-mile Grand Canal that linked the Yellow River with the Yangtze River.

In Dunhuang (population: 180,000), another oasis farming community in the Gobi Desert, I was able to take a close-up look at cotton production. Farms in Dunhuang are smaller than Turpan’s vineyards. Farm families raise cotton on irrigated plots of ground called mus (1 mu = 1/6th acre).

Cotton is hand-harvested by laborers four times during September and October as the crop matures. The last picking was just being completed as I walked fields and observed the age-old process of plucking fluffy cotton from the bolls, then stuffing the cotton into white sacks.

Watching the harvest reminded me of the phrase used to describe on-farm hog butchering: “Every is utilized but the squeal.” All parts of the cotton plant are also utilized.

Cotton is separated from the seed at the cotton gin. Seeds are pressed into oil that is used by farmers for cooking. Back at the field, farmers cut and completely remove all cotton plants from their individual plots and haul them to their homes, where the woody-stemmed plants are burned in stoves as a wood-substitute fuel for cooking. Finally, all remaining leaves and empty cotton bolls in the field are swept into piles, collected into sacks and burned during winter under clay-brick beds to keep family members warm as they sleep at night.

2004 was a good year for growing cotton in China, thanks to the 2003 SARS epidemic. The price of cotton rose 25% as a result of mass production of white cotton masks distributed to China’s population to reduce exposure to the respiratory disease.

There are large farm fields and mechanized agriculture in China but I didn’t see many examples on this trip. Much of China’s agriculture is still practiced the way it has been done for centuries.

As capitalism and private enterprise gain footholds in this fast-changing economy, entrepreneurial farmers will discover ways to operate more land, manage larger numbers of livestock and market their production more profitably. Media stories and tourists’ reports about China’s progress on all fronts during the next decade will be interesting to follow.