Land-Surface Subsidence in the Houston-Galveston Region, Texas

Development of ground water in the Houston-Galveston region, Texas, began in the 1890's. Pumping of ground water from the Chicot and Evangeline aquifers for municipal supply, industrial use, and irrigation was about 23 cubic meters per second by 1974. Pumping of large amounts of ground water has resulted in water-level declines during 1943-73 of as much as 61 meters in wells completed in the Chicot aquifer and as much as 99 meters in wells completed in the Evangeline aquifer. The declines in artesian pressures have resulted in pronounced regional subsidence of the land surface. The center of subsidence is east-southeast of Houston at Pasadena, where as much as 2.3 meters of subsidence occurred between 1943 and 1973. The maximum amount of subsidence during 1964-73 was about 1.1 meters. The area in which subsidence is 0.3 meter or more has increased from about 906 square kilometers in 1954 to about 6,475 square kilometers in 1973. Water from Lake Livingston on the Trinity River, about 97 kilometers east of Houston, will become available in 1976. As a result, it is estimated that ground-water pumping will decrease by about 3.1 cubic meters per second in the area of maximum artesian-pressure decline and subsidence. The recovery of water levels is expected to decrease the rate of subsidence substantially. (Woodard-USGS)