The Search for “New” Groundwater Sources: Assessing Unconventional Aquifers

The rising demand for energy has driven the innovation for new methods of unconventional natural resource extraction. While the use of such methods remains highly controversial, “new” resources not previously considered accessible, are now economically feasible to produce. Recently, the demand for groundwater has followed a similar trend. Traditional aquifers, highly stressed by rapidly changing demographics, provide an impetus to explore groundwater systems previously disregarded. Brackish water in deep confined systems is currently being discussed as a potential source where treatment or blending with fresher water may allow for increased production. Shallow systems, susceptible to contamination and often considered unappealing as drinking water sources, are now targeted for a variety of non-potable uses. Thin or slowly permeable units with varying water quality may be able to supplement currently produced groundwater or surface water. However, these “new” unconventional sources are neither isolated nor completely independent. The effective and efficient development of these unconventional aquifers will depend upon an organized and discerning approach that evaluates positive attributes and negative consequences. A broad assessment of several unconventional groundwater sources are presented in response to the current Texas drought experience. “New” sources of potential groundwater in the Edwards, Trinity, and Brazos River alluvium aquifers are evaluated along with shallow seasonal flow systems not officially considered aquifers.