Imbalance in the modern hydrologic budget of topographic catchments along the western slope of the Andes (21–25°S): implications for groundwater recharge assessment

Relic Groundwater and Prolonged Drought Confound Interpretations of Water Sustainability and Lithium Extraction in Arid Lands

“…To illustrate the meaning of our findings we compare the existing conceptualization of the SdA water budget used by the DGA to manage water use in the basin (DGA, 2013) to a revised conceptualization that incorporates our understanding of water fluxes and sources (Boutt et al., 2021). These conceptualizations are summarized in a Sankey diagram (Figure 9) that shows the pre‐development understanding of the water budget (Figure 9a, 9c) and the impacts that anthropogenic water use would have on the water budget (Figure 9b, 9d).…”

“…The SdA basin catchment is a large and deep topographic depression of about 17,000 km 2 that spans a vertical profile of >3,500 m, its basin floor (2,900 km 2 ) is covered mostly by evaporite sediments with some clastic material and hosts a vast halite nucleus covering about 1,700 km 2 . The water budget and physical hydrology of the SdA region have been the focus of several recent studies (Boutt et al., 2021; Corenthal et al., 2016; Houston, 2007; Munk et al., 2018). A summary of the key hydrological attributes at SdA is introduced here (Figure 1b).…”

“…Yet for the Salar de Atacama (SdA), which represents the largest single recoverable lithium resource in the world with approximately 42% of the global reserve base as of 2021 (Cabello, 2021; USGS, 2022), no studies to date have constrained the capability of the basin's water budget to meet current water demands, possibly because of notable uncertainty between permitted water use and actual extraction (Babidge et al., 2019), and the lack of legitimate sustainability metrics. Rapidly increasing global demand for lithium (Ambrose & Kendall, 2020; Kesler et al., 2012) coupled with the hydrologic imbalance between recharge and discharge in this basin (Boutt et al., 2021) therefore necessitates a critical examination of water sustainability in light of anthropogenic and climatic pressures on these environments.…”

Hydroclimatological Patterns and Limnological Characteristics of Unique Wetland Systems on the Argentine High Andean Plateau

“…Indeed, Liu et al [15] showed that one in three of these catchments had an effective catchment area larger or smaller than the topographic catchment, leading to large discrepancies in water budgets. These hydrological imbalances within a catchment may be reconciled by the subsurface interbasin flow between topographic drainages and/or the draining of stored groundwater recharged during wetter periods hundreds to thousands of years before the present [16]. These processes are well documented globally [13,[16][17][18]; and particularly in the Chilean pre-Andean depression, where relevant contributions have been made recently [19][20][21][22].…”

“…These hydrological imbalances within a catchment may be reconciled by the subsurface interbasin flow between topographic drainages and/or the draining of stored groundwater recharged during wetter periods hundreds to thousands of years before the present [16]. These processes are well documented globally [13,[16][17][18]; and particularly in the Chilean pre-Andean depression, where relevant contributions have been made recently [19][20][21][22]. As in other arid regions of South America, these kinds of studies are relatively scarce in Argentina.…”