Rapid groundwater decline and some cases of recovery in aquifers globally

Abstract

Groundwater resources are vital to ecosystems and livelihoods. Excessive groundwater withdrawals can cause groundwater levels to decline1–10, resulting in seawater intrusion11, land subsidence12,13, streamflow depletion14–16 and wells running dry17. However, the global pace and prevalence of local groundwater declines are poorly constrained, because in situ groundwater levels have not been synthesized at the global scale. Here we analyse in situ groundwater-level trends for 170,000 monitoring wells and 1,693 aquifer systems in countries that encompass approximately 75% of global groundwater withdrawals18. We show that rapid groundwater-level declines (>0.5 m year−1) are widespread in the twenty-first century, especially in dry regions with extensive croplands. Critically, we also show that groundwater-level declines have accelerated over the past four decades in 30% of the world’s regional aquifers. This widespread acceleration in groundwater-level deepening highlights an urgent need for more effective measures to address groundwater depletion. Our analysis also reveals specific cases in which depletion trends have reversed following policy changes, managed aquifer recharge and surface-water diversions, demonstrating the potential for depleted aquifer systems to recover.

Groundwater Depletion. Are Environmentally Friendly Energy Recharge Dams a Solution?

“…Groundwater depletion is a global issue and newer studies reveal the extent of the problem. Jasechko et al [5] studied groundwater depletion on a global scale and proposed various actions including the application of managed aquifer recharge on a global scale. Other factors that should be included in groundwater depletion forecasts are land use/land cover change and population growth [58].…”

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Estimating irrigation water use from remotely sensed evapotranspiration data: Accuracy and uncertainties across spatial scales

“…As such, groundwater use plays a critical role in global food production and trade (Dalin et al, 2017) and sustaining local and regional economies (Deines et al, 2020). However, groundwater use can also lead to detrimental outcomes, such as the depletion of interconnected surface water resources (de Graaf et al, 2019;Zipper et al, 2022), declining water levels and storage capacity in regionally-and globally-important aquifers (Hasan et al, 2023;Jasechko et al, 2024), and associated water scarcity and insecurity (D'Odorico et al, 2019;Marston et al, 2020). In many agricultural settings without alternative water sources, pumping reductions are the only currently viable tool available to reduce water abstraction and slow water table decline rates (Butler et al, 2020).…”

Can eXplainable AI Offer a New Perspective for Groundwater Recharge Estimation?—Global‐Scale Modeling Using Neural Network

“…Estimating the groundwater recharge rate has been one of the most important tasks for hydrologists since it constitutes one of the key parameters determining the safe yield-the amount of water that is replenished and thus can be sustainably withdrawn (Blöschl et al, 2019;Oki & Kanae, 2006). Currently, rapid decline of groundwater levels has been observed worldwide and accelerated during the past four decades in 30% of aquifers (Jasechko et al, 2024). This is especially alarming in regions where surface water resources are either generally scarce, not constantly available in time and space, or contaminated, so that the population is primarily dependent on groundwater (Schulz et al, 2024).…”