DIGGING DEEPER FOR GROUNDWATER

The State of Texas withdraws groundwater from nine major aquifers to meet the demands of the more than 27 million people living in the state. Most groundwater pumped today is used for agriculture, but municipal demands are expected to surpass agricultural use by 2060 when the Texas population is predicted to double. Wells recorded in the Texas Water Development Board’s Groundwater Database were analyzed for long-term trends in the depths of wells drilled. Box-and-whisker plots were generated for each major aquifer between 1900-2015, and hypotheses based on regional history are listed explaining any trends found in the data. These hypotheses include: The shallowest well drilled each year reflects deepening water tables, the presence or absence of droughts, hydrostratigraphic variations, and the improvement of technology (such as desalination plants) and agricultural techniques that have helped ease the stress on groundwater supplies. All major aquifers except the Edwards (Balcones Fault Zone) and the Hueco-Mesilla Bolsons Aquifers show noticeable deepening of well depths. The time trend correlation between well depths and water levels highlights the anthropogenic influence and stress placed on groundwater, and the importance of conservation for future sustainability.