I first visited the Gandhak Ki Baoli, an eight hundred year old step well in the Mehrauli neighborhood of New Delhi, India, in the late 1990's. It was and is an impressive structure. Unlike a conventional round well in which water is hauled up and down a vertical shaft in a bucket, a step well is built like a broad staircase descending into the depths of the earth. This allows the people using the well to walk down to the level of the water as it rises and falls with the seasons. There they can wash clothes, draw water and even bathe.
The Gandak Ki Baoli was built in the reign of Sultan Iltutmish, a 13th century ruler of what was then the city of Mehrauli. When it was originally constructed, this huge five-tiered structure not only provided water for the population around it but also provided a cool, secluded spot for relaxation and refreshment during the long months of hot Indian weather. As late as the early 1970's divers would jump from the sides of the well into the water below "for the amusement of visitors".
All that was in the bottom of the Gandak Ki Baoli when I first visited it was dust and trash. It remains bone dry to this day. The reason is not hard to fathom. The water table in New Delhi, and throughout much of India, is falling precipitously.
In the Indian State of Bihar, the water table has dropped by 2.5 meters in the last twenty years. The rate of decline is increasing. The water table is now falling by 13 centimeters, about five inches, every year. In Punjab, the "bread basket" of India, the situation is worse. The water table there has fallen more than 20 meters in the last decade. In Tamil Nadu, a state of 62 million people in southern India, 95 percent of wells owned by small farmers have dried up. Less than half as much land is irrigated in Tamil Nadu today than it was a decade ago.
Put simply, India is drawing much more water out of the ground via wells than is replenished naturally. In effect, India is "mining" the aquifers on which it sits. Nationwide, some 175 million Indians depend on agricultural production that is only viable because of over pumping. Once the existing water supply is consumed, that agricultural production will no longer be possible.
It's an alarming situation. When the water supplies are exhausted, hundreds of millions of people will be threatened with famine. It gets worse. This is not just an Indian phenomenon. It is one being experienced worldwide. In fact, half the world's population lives in areas with falling water tables.
Water tables are plummeting all across northern China including under areas, which produce large portions of China's wheat and corn crops. Already in China grain harvests are beginning to decline. As a direct result of a reduction in the amount of irrigated farmland, Chinese wheat production fell by 27 percent between 1997 and 2004.
Saudi Arabia announced in 2008 that its natural aquifer was almost entirely depleted. Since then its domestic wheat harvest has fallen by two thirds. That production will soon cease entirely, and the entire population of Saudi Arabia will be dependent on imported wheat.
Yemen, Syria and Iraq also face serious water shortages. In Jordan, over the last four decades, grain production has dropped by eighty percent. Sanaa, the capital of Yemen, is literally running out of water. Wells over a thousand feet deep are going dry. There is serious discussion that this city, with a population of 2,000,000, may have to be abandoned within twenty years because of a lack of drinking water.
Deserts are advancing across the globe. The world's largest desert, the Sahara, is growing in all directions. In the north it is pressing the populations of the North African nations against the coast. In the south it is effectively devouring the broad band of savannah that separates the Sahara from the jungles of central Africa. The populations of the this savannah region are being driven southward, away from their villages and farms, and into a smaller and smaller sliver of habitable territory.
By one estimate, over the last 50 years, 24,000 villages in northern and western China have been abandoned because of desert expansion. An area the size of Rhode Island is lost to desertification in China annually. One quarter of the entire land mass of China is now desert.
Much of the impetus for the so-called Arab Spring of 2011 was provided by a rise in food prices. Relatively modest increases in food costs, which would be regarded as an inconvenience here in the United States, have disastrous consequences in societies where income levels are perilously low and a much higher proportion of individual income is spent purely on subsistence.
Such unrest is likely to be only a mild precursor, however, to what we will see in the coming decades as the inevitable consequences of the destruction of natural aquifers and runaway population growth are experienced. Entire cities may disappear and huge rural populations, living literally hand to mouth on food production made possible only by irrigation, may descend into anarchy.
How long we have before the crisis hits is a matter of some dispute. In some areas it may be decades away. In others it could happen any day. One thing is certain. A great many nations in the world are already running on empty, and we are all going to feel the results.