Ogalla Aquifer Research Paper
Josh Wiza
Extra Credit
Ogallala Aquifer
The Ogallala Aquifer occupies the High Plains of the United States, extending northward from western Texas to South Dakota. The Ogallala is the leading geologic formation in what is known as the High Plains Aquifer System. The entire system underlies about 174,000 square miles throughout eight states.
The Ogallala aquifer is an unconfined aquifer, and nearly all recharge comes from rainwater and snowmelt in certain areas. As the High Plains has a warmer climate, recharge is minimal especially towards the southern part of the aquifer. “Recharge varies by amount of precipitation, soil type, and vegetation cover and averages less than 25 millimeters (1 inch) annually for the region
as a whole. In a few areas, recharge from surface water diversions has occurred. Groundwater does flow through the High Plains Aquifer, but at an average rate of only 300 millimeters (12 inches) per day (pubs.water.usgs.gov/fs029-01 - 19k).” “The depth to the water table of the Ogallala Aquifer varies from actual surface discharge to over 150 meters (500 feet). Generally, the aquifer is found from 15 to 90 meters (50 to 300 feet) below the land surface. The saturated thickness also varies greatly. Although the average saturated thickness is about 60 meters (200 feet), it exceeds 300 meters (1,000 feet) in west-central Nebraska and is only one-tenth that in much of western Texas. Because both the saturated thickness and the areal extent of the Ogallala Aquifer is greater in Nebraska, the state accounts for two-thirds of the volume of Ogallala groundwater, followed by Texas and Kansas, each with about 10 percent (pubs.water.usgs.gov/fs029-01 - 19k).” The Ogallala aquifer provides water for residential, industrial, and agricultural use. This large aquifer is mostly used for its widespread of irrigation. Farming accounts for 94 percent of the groundwater use which is needed for the regional economy. “It supports nearly one-fifth of the wheat, corn, cotton, and cattle produced in the United States. Crops provide grains and hay for confined feeding of cattle and hogs and for dairies. The cattle feedlots support a large meatpacking industry. Without irrigation from the Ogallala Aquifer, there would be a much smaller regional population and far less economic activity (www.kerrcenter.com).”
The Ogallala aquifer is depleting and in some areas being polluted. Irrigation withdraws much groundwater, yet little of it is replaced by recharge. Since large-scale irrigation began in the 1940s, “water levels have declined more than 30 meters (100 feet) in parts of Kansas, New Mexico, Oklahoma, and Texas. In the 1980s and 1990s, the rate of groundwater mining, or overdraft, lessened, but still averaged approximately 82 centimeters (2.7 feet) per year (co.water.usgs.gov).”
Increased efficiency in irrigation continues to slow the rate of water level decline. State governments and local water districts throughout the region have developed policies to promote groundwater conservation and slow or eliminate the expansion of irrigation. All in all, management has emphasized planned and orderly depletion, not sustainable yield. The future economy of the High Plains depends heavily on the Ogallala Aquifer because it is the main source of water for all uses. The Ogallala will continue to be the Fountain of youth of this region only if it is managed properly to limit both depletion and contamination.
Extra Credit
Ogallala Aquifer
The Ogallala Aquifer occupies the High Plains of the United States, extending northward from western Texas to South Dakota. The Ogallala is the leading geologic formation in what is known as the High Plains Aquifer System. The entire system underlies about 174,000 square miles throughout eight states.
The Ogallala aquifer is an unconfined aquifer, and nearly all recharge comes from rainwater and snowmelt in certain areas. As the High Plains has a warmer climate, recharge is minimal especially towards the southern part of the aquifer. “Recharge varies by amount of precipitation, soil type, and vegetation cover and averages less than 25 millimeters (1 inch) annually for the region
as a whole. In a few areas, recharge from surface water diversions has occurred. Groundwater does flow through the High Plains Aquifer, but at an average rate of only 300 millimeters (12 inches) per day (pubs.water.usgs.gov/fs029-01 - 19k).” “The depth to the water table of the Ogallala Aquifer varies from actual surface discharge to over 150 meters (500 feet). Generally, the aquifer is found from 15 to 90 meters (50 to 300 feet) below the land surface. The saturated thickness also varies greatly. Although the average saturated thickness is about 60 meters (200 feet), it exceeds 300 meters (1,000 feet) in west-central Nebraska and is only one-tenth that in much of western Texas. Because both the saturated thickness and the areal extent of the Ogallala Aquifer is greater in Nebraska, the state accounts for two-thirds of the volume of Ogallala groundwater, followed by Texas and Kansas, each with about 10 percent (pubs.water.usgs.gov/fs029-01 - 19k).” The Ogallala aquifer provides water for residential, industrial, and agricultural use. This large aquifer is mostly used for its widespread of irrigation. Farming accounts for 94 percent of the groundwater use which is needed for the regional economy. “It supports nearly one-fifth of the wheat, corn, cotton, and cattle produced in the United States. Crops provide grains and hay for confined feeding of cattle and hogs and for dairies. The cattle feedlots support a large meatpacking industry. Without irrigation from the Ogallala Aquifer, there would be a much smaller regional population and far less economic activity (www.kerrcenter.com).”
The Ogallala aquifer is depleting and in some areas being polluted. Irrigation withdraws much groundwater, yet little of it is replaced by recharge. Since large-scale irrigation began in the 1940s, “water levels have declined more than 30 meters (100 feet) in parts of Kansas, New Mexico, Oklahoma, and Texas. In the 1980s and 1990s, the rate of groundwater mining, or overdraft, lessened, but still averaged approximately 82 centimeters (2.7 feet) per year (co.water.usgs.gov).”
Increased efficiency in irrigation continues to slow the rate of water level decline. State governments and local water districts throughout the region have developed policies to promote groundwater conservation and slow or eliminate the expansion of irrigation. All in all, management has emphasized planned and orderly depletion, not sustainable yield. The future economy of the High Plains depends heavily on the Ogallala Aquifer because it is the main source of water for all uses. The Ogallala will continue to be the Fountain of youth of this region only if it is managed properly to limit both depletion and contamination.