Rain Enhancement of Aquifer Recharge across the West Texas Weather Modification Association Target Area
Groundwater is critical to the economy and livelihood of west Texas, with particular importance to arid and semi-arid environments where precipitation is limited and highly variable. In the absence of significant surface-water resources, most land owners rely on groundwater as the sole resource for agricultural, municipal, and economic development needs. Unfortunately, groundwater resources in arid and semi-arid environments are stressed due to increased demands and variable recharge rates and mechanisms.
Rainfall enhancement has been shown using matched cloud analysis to increase precipitation by 8-20% across an eight-county area in west Texas during 2004–2013. This translates to an increase of rainfall as much as 2 in/yr. Confirmatory analysis at 10 rain gauges within the west Texas target area indicates that since 2004 precipitation exhibited an 8% increase when compared with precipitation at 15 rain gauges in the surrounding area outside of the target area.
A precipitation/recharge correlation developed for the semi-arid environment of west Texas was used to determine how much additional recharge has been realized from the rain-enhancement operations that were conducted for the eight-county target area. Using this correlation, recharge to the Edwards-Trinity Aquifer is calculated to have been enhanced by over 1.0 million acre-ft during the period of 2004–2013 across the eight-county target area.