Abstract

Water Levels and Subsidence in the Houston-Galveston Region, Texas
Track: Water Resources
Authors: Michaela Johnson

The U.S. Geological Survey, in cooperation with the Harris-Galveston Subsidence District, City of Houston, Fort Bend Subsidence District, and Lone Star Groundwater Conservation District has investigated the relation of groundwater withdrawal and land-surface subsidence in the Houston-Galveston region, Texas. The Chicot, Evangeline, and Jasper aquifers are the three primary aquifers in the Gulf Coast aquifer system in this region. Large withdrawals of water from the Chicot and Evangeline aquifers have caused potentiometric-surface declines, causing compaction of clay layers in the aquifer sediments. Annual water-level measurement data collected from the well-monitoring network in 11 counties have been used to produce 35 years of maps depicting water-level altitudes and water-level changes in the 3 aquifers. In 2011, regional land-surface subsidence contours were interpolated using 2000-2010 elevation data obtained from GPS records to provide an updated depiction of ongoing subsidence; subsidence continues to occur in areas where groundwater withdrawals have not been curtailed.