Measuring The Effectiveness of Groundwater Management Policies for the Carrizo-Wilcox Aquifer of Texas

In the United States, more than 80% of the population now lives in urban areas. By 2050, a significant portion of that population will live in megaregions consisting of two or more metropolitan areas linked with interdependent environmental systems, a multimodal transportation infrastructure, and complementary economies. The Texas Triangle Megaregion, one of 8 to 10 such regions in the United States, is spatially delineated by the metropolitan areas of Dallas/Fort Worth, Austin, San Antonio, and Houston, with a total land size of nearly 35,435 square kilometers.

Supporting the modern industrial infrastructure of a major metropolitan megaregion has required extensive water-related modifications to the critical zone. These modifications come in the form of an extensive network of dams and reservoirs; a high-density matrix of wells for extracting water, oil, and gas from the critical zone; significant alterations of land cover; and interbasin transfer of ground and surface water. Progressive depletion of critical zone reserves threatens sustainable development in the heavily groundwater-dependent Texas Triangle and requires robust and effective water resource policy for the megaregion to remain economically viable.

Facing growth that is expected to double the population of the state to more than 46 million by 2060, Texas has increased its efforts to implement comprehensive water resources planning during the past decade. State policy in Texas dictates that groundwater management is best accomplished through locally elected, locally controlled groundwater conservation districts (GCD).

This study examined the effectiveness of GCDs as a water resource management tool in Texas. This research demonstrated no measurable difference in the annual rate of decline in groundwater levels in the Carrizo-Wilcox Aquifer in Texas after establishment of a GCD. The data did not show a correlation between the water allocation method used and the impact on average annual drawdown of the aquifer. The study was not able to demonstrate a relationship between the length of time a GCD has been in existence and the average annual drawdown rates in the aquifer.