How has America's water use changed over the last 50 years? Are we using more or less water, and are there trends for different kinds of water use? There is a lot of information in this bar graph. It shows the amount of water used for various categories of water use from 1950-2000. This chart is from U.S. Geological Survey Circular 1268, "Estimated Use of Water in the United States in 2000."
Data table of trends in water use in the United States 1950-2000.
The bars that stand out most are the yellow ones -- water for electricity production. Electricity water use increased almost 500 percent from 1950 to 2000. Irrigation water use increases by about 50 percent -- it takes more water to grow food for our increasing population. Notice how after 1980 water use started a bit. Maybe after 1980 we started using more water-conservation measures. What do you think? The purple public-supply boxes are important. Notice how they continue on an uptrend. Public-supply water (water withdrawn by the local county and city water departments and delivered to homes and businesses) goes to serve our normal water uses, such as supplying industries, restaurants, and homes with water. Our ever-increasing population demands ever-increasing supplies of water.
The next chart shows the trends in surface-, ground-, and total water withdrawals for the Nation from 1950 to 2000. Notice how the relative amouts of surface- and ground-water withdrawals (in percentages) has remained fairly constant. About three-fourths of the water used in America comes from surface water. This chart is from U.S. Geological Survey Circular 1268, "Estimated Use of Water in the United States in 2000."
The majority, about 74 percent, of freshwater used in the United States came from surface water in 2000. The largest user of surface water is the thermoelectric-power industry, which uses it to cool electricity-generating equipment. Most of this water is returned directly to the environment, unlike in irrigation, in which much of the water is consumed. Only the public-supply sector, which uses about 10 percent of fresh surface-water withdrawals, has increased continually since 1950. This makes sense since publically-supplied water goes directly towards America's ever-growing population. Since 1950, the ground-water portion of total water withdrawals in the United States has remained at about 80 percent..
Ground water is vitally important in supplying water for our Nation's everyday water needs, with the most significant use being for irrigation and public water supply. Since 1950, the ground-water portion of total water withdrawals in the United States has remained at about 20 percent. The vast amount of ground water used is freshwater, with a small amount of saline water going to mining uses. Ground water is used to irrigate crops and supply homes, businesses, and industries with water.
U.S. Department of the Interior | U.S. Geological Survey
URL: http://ga.water.usgs.gov/edu/totrendbar.html
Page Contact Information: Howard Perlman
Page Last Modified: Friday, 07-Nov-2008 15:46:24 EST
