Characterizing Brackish Water in New Mexico

Recurring severe droughts in New Mexico require consideration of non-traditional water resources, including brackish water. However, better characterization of this resource is needed. In New Mexico, brackish water resources have been cited for decades as extensive and readily available, with as much as 75% of the state’s groundwater estimated to be brackish or saline water. Brackish water resources (1000-10,000 ppm TDS) are largely found within regional basins, incorporating geology complicated by rift basin faulting, episodic volcanism, and extensive deformation. The diverse geology creates regional and local variability in water chemistry, as well as with depth. Complete and accurate datasets are required to promote research on water resources, across the various stratigraphic units and among fresh, brackish, and saline waters. The general goal of the Aquifer Mapping Program at the New Mexico Bureau of Geology and Mineral Resources is to characterize all of the state’s aquifers in terms of water quality, quantity, and distribution. Currently, we are undertaking a fundamental step in characterizing New Mexico’s brackish waters through a major water quality data compilation effort. In addition to our own data, the datasets and databases will incorporate data from the New Mexico Environment Department, the New Mexico Office of the State Engineer, the U.S. Geological Survey, municipalities, consultants, and researchers. Historic data that has previously only been available in printed reports is also being digitized and incorporated into these datasets. This effort will lead to improved water quality data availability for the state, identification of target regions for brackish water use based on geologic and hydrologic data, and improved understanding of possible interconnections of fresh and brackish water resources. These efforts also will shed light on spatial and chemical data gaps.