Timothy (Jak) J Kearns
University of Houston, USA
Posters-Accepted Abstracts: J Aeronaut Aerospace Eng
In this study we summarized land subsidence and groundwater level changes that have occurred in the Houston metropolitan area during the past eight years (2005-2012). The Chicot and Evangeline aquifers are the major aquifers that underlie the Houston metropolitan area. Subsidence measurements from 95 permanent Global Positioning System (GPS) stations and 11 borehole extensometers and groundwater level measurements from 170 wells screened in the Chicot aquifer and 320 wells screened in the Evangeline aquifer were investigated. GPS and extensometer observations indicate that the overall subsidence rate in the Houston area has been decreasing since 2005. Currently, subsidence in downtown Houston and in the southeastern region of the Houston metropolitan area has nearly ceased (<3 mm/year). However, subsidence is occurring at a rate as rapid as 2.5 cm/year in the western and northern regions of the Houston metropolitan area. This study indicates that the local preconsolidation heads were approximately 30 to 40 meters below the land surface. The land subsidence rate is decreasing in the areas where the water level is rising, but still below the preconsolidation head. The rate of land subsidence is steady in the areas that groundwater head is declining and below the preconsolidation head.