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The Effects of Industrialism on Our Water Table

Human beings can directly tap less than 1 percent of Earth's freshwater, meaning only about about 0.007 percent of the total global water supply. About 97 percent of the freshwater potentially available for human use is groundwater, or the water table, which consists of underground streams and aquifers, or water-saturated layers of materials like rock. Intensifying industrial-scale depletion and contamination of groundwater contribute to the water stresses and scarcities that an ever-increasing sector of humankind suffers.

  1. Industrial Groundwater Uses

    • In every region of the world, numerous industries, including thermoelectric power generation, manufacturing and mining and extraction depend upon vast supplies of groundwater. Farming is the largest consumer of groundwater, particularly the industrialized "conventional" agriculture that has proliferated globally since World War Two and relies heavily on manufactured fertilizers and pesticides and unsustainable forms of irrigation.

    Water Debt

    • Earth's natural hydrological or water cycle replenishes groundwater supplies chiefly through rainfall and snow melt on land.Human activities are said to work within an area's "water budget" when they do not withdraw more from the groundwater than can be naturally replenished. "Water debt" occurs when human activities decrease the overall amount of available groundwater or render it unusable. Groundwater depletion doubled worldwide between 1960 and 2000.

    Reduced Water Supply

    • Groundwater depletion obviously cuts down the overall amount of available water. When wells dry up, it may be too expensive or technically impossible to dig deeper. The human ability to withstand aridity and drought is compromised. In coastal areas, remaining groundwater may become too saline for use.

    Pollution

    • Whether or not the amount of groundwater is sufficient, pollution from pathogens or chemicals can reduce the amount fit for human use. Untreated wastewater discharges can introduce disease-causing microbes like hepatitis A or salmonella into the water table. Runoff from agriculture and manufacturing can contaminate groundwater with dangerous chemicals like nitrates, polychlorinated biphenyls (PCBs) and pesticides.

    Threatened Food Production

    • Only 18 percent of global farmland is irrigated, yet it produces 40 percent of the world's food. According to National Geographic freshwater fellow Sandra Postel, groundwater depletion threatens this "cornerstone of global food security." According to her calculations, the 75 trillion gallons of groundwater depleted in the year 2000 alone could feed 943 million people enough grain for one year.

    Land Subsidence

    • Groundwater depletion has already caused land subsidence, or sinking and collapse of land, especially in earthquake-prone areas such as California, Mexico and Thailand. Some places in California's San Joaquin Valley have sunk 30 feet since the early twentieth century. A major earthquake could trigger widespread land subsidence and infrastructure destruction in groundwater-depleted Dhaka, Bangladesh's capital and home to 15 million people.

    Rising Sea Levels

    • According to researchers from the University of Utrecht, Holland and the World Meterological Organization's International Groundwater Resources Assessment Centre, groundwater depletion has created about one-quarter of the observed rise in global sea level. Scientists have long hypothesized that large quantities of groundwater used in irrigation evaporates and rains into the ocean, or it ends up in river systems that drain into the sea.

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