Falling Water Tables Threaten Agricultural Production and Populations Around the World

Falling water tables around the world are threatening agricultural production and the livelihoods and well being of millions of people. Farmers are digging deeper wells, in some cases applying oil drilling techniques to reach water up to 400 meters below the surface. Farmers are also running larger electric water pumps around the clock, creating challenges in the power sector and increasing agricultural costs . In India, for example, power companies spend approximately $9 billion per year subsidizing power for irrigation, twice as much as the country spends on education. Examples include:

• India - In North Gujaret, the water table is falling by 20 feet per year. In Tamil Nadu, the drying wells have reduced the amount of irrigated farm land by 50 percent in the last ten years.

• Pakistan - In Rawalpindi and Islamabad, waters tables fell an average between 1 and 2 meters per year between 1982 and 2000. In Baluchistan, water tables are falling approximately 3.5 meters per year.

• Iran - In the Chenaran Plain, in northeastern Iran, water tables were falling by 2.8 meters per year in the late 1990s.

• United States - Water from the Ogallala aquifier, which stores water for Nebraska, Oklahoma and Texas, is being withdrawn between 130 and 160 percent above its replacement rate, leading to possibly being depleted within 40 years.

The critical concern over time is the continued overdraft of subsurface and surface water resources at the same time that increasing populations are creating greater demand on agriculatural production. Our global agricultural system is drawing upon water resources at rates that exceed the natural and sustainable replenishment rates. In rural areas of India, farmers are spending successively more resources to acquire water, by drilling deeper wells and running pumps longer. In some cases, towns are abandoning their wells, governments are trucking in water, and people are migrating away from water-poor locations.

More sustainable agricultural practices have to be adopted to reverse the accelerating depletion of available fresh water resources. Similar to the peak oil analysis done by Shell geologist M. King Hubbert in 1956, there is an explicit amount of fresh water resource available at any one time, governed by its natural replenishment rate. Unless we utilize water resources in a manner governed by natural replenishment rates, billions of people are at risk for the two most fundamental requirements for survival: food and water.