Brackish groundwater may offer a partial solution to water demands. The USGS recently published Fact Sheet 2018-3010, which describes brackish water resources within five principal aquifers in the Southwest Basins region. These aquifers span Arizona, New Mexico, Utah, Nevada, and California, and parts of Colorado and Idaho. The fact sheet explains the modeling methodology used to extrapolate from well observations to estimate the total brackish water resources in the region. It then discusses the potential for developing and using brackish groundwater to meet water resource needs. Additional data can be found in the national brackish groundwater assessment, the basis for the fact sheet.
Download the 6-page fact sheet in PDF format here.
Abstract
Secure, reliable, and sustainable water resources are fundamental to food production, energy independence, and the health of humans and ecosystems. But the large-scale development of fresh groundwater resources has stressed aquifers in some areas, causing declines in the amount of groundwater in storage and decreases in discharge to surface-water bodies like rivers and springs (Reilly and others, 2008). In some parts of the southwestern United States, the water supply is not adequate to meet demand without substantial effects on groundwater storage or surface discharge, and severe drought intensifies the stresses affecting water resources.
In support of the national census of water resources, the U.S. Geological Survey (USGS) completed the national brackish groundwater assessment to provide information about brackish groundwater as a potential resource to augment or replace freshwater supplies (Stanton and others, 2017). The objectives of the brackish groundwater assessment were to consolidate available data into a comprehensive database of brackish groundwater resources in the United States and to produce a summary report about the distribution, physical and chemical characteristics, and use of brackish groundwater. This fact sheet summarizes the occurrence of brackish groundwater and factors affecting its usability in the southwestern United States (specifically the Southwest Basins region) reported for the national study. The map below (fig. 1) summarizes the brackish zones for the five largest principal aquifers within the southwestern United States, along with groundwater resources in the remaining part of the region (Reilly and others, 2008).