Water Profile

Montana, North Dakota and South Dakota

Published April 1, 1992  | April 1992 issue


  • Per capita water usage: 10,500 gallons per day.
  • Montana withdraws 8.6 billion gallons of water each day, making it the 13th largest water user among the states. Agriculture dominates Montana's water usage, accounting for 97 percent of withdrawn water. At about 8.4 billion gallons per day, Montana is the fifth largest user of water for agricultural purposes.
  • Montana has two distinct regions: The west and south central regions get as much as 100 inches of precipitation annually in the higher mountains and as little as 10 inches in the valleys; in the eastern and north central parts of the state, average precipitation is about 12 inches annually.
  • While ground water is available in nearly all parts of the state, it only accounts for about 2 percent of total withdrawals; still, about half of Montanans depend on ground water for domestic use.
  • Major water issues for the state include periodic shortages in some basins, especially due to drought; possible environmental damage due to mining, agriculture and forestry; and water-rights questions.

Source: National Water Summary (Series, 1983-88), U.S. Geological Survey.

North Dakota

  • Per capita water usage: 1,690 gallons per day.
  • North Dakota withdraws 1.2 billion gallons of water each day, putting it 43rd among the states. Thermoelectric power production accounts for 76 percent of North Dakota's water use; 15 percent is used for agriculture.
  • Annual precipitation in the state ranges from 13 inches in the northwest to about 20 inches in the east. About 75 percent of the state's precipitation falls between April and September. North Dakota's precipitation is subject to a high evaporation rate; likewise, its ground water sources are often not fully recharged, worsening the impact of occasional periods of drought.
  • Although 62 percent of the population relies on ground water for its domestic use, six of the state's 10 largest cities use surface water.
  • Natural wetlands, which provide an important water resource for migrating waterfowl and wildlife, cover more than 2 million acres in the central part of the state.

Source: National Water Summary (Series, 1983-88), U.S. Geological Survey.

South Dakota

  • Per capita water usage: 956 gallons per day.
  • South Dakota withdraws 674 million gallons of water each day from ground water and surface water sources, ranking it number 46 among the states in water usage. Three-quarters of the state's water supply is used for agriculture, and 8 percent for industry and mining.
  • The state averages 18 inches of precipitation annually, 14 in the northwest and 25 in the southwest.
  • Except for the Missouri River, most streams and rivers don't provide a dependable water supply. West of the Missouri River, 76 percent of the water supply is drawn from surface sources, and 73 percent of that goes to agriculture. East of the Missouri, 70 percent of the total supply comes from ground water, 60 percent of which is for agriculture.
  • South Dakota has been actively pursuing new industrial development in recent years, and the supply of water has become an issue in some regions. Since 1987, several important water-resource developments have begun, including rural water systems, river improvement, lake restoration, irrigation development and flood control.

Source: National Water Summary (Series, 1983-88), U.S. Geological Survey.