Technical Commentary/ Aquifer Recharge and Overexploitation: The Need for a New Storyline by Franc¸ois Molle 1 Groundwater has been the star in 2022, with a UN World Water Development Report and countless other policy documents, reports, conferences and webinars devoted to the “invisible resource.” Unsurprisingly, groundwater overexploitation emerged as a central theme; yet, a puzzling—and very damaging—storyline was frequently reiterated. (A storyline is defined by Hajer [2006:69] as “a condensed statement summarizing complex narratives, used by people as ‘short hand’ in discussions.”) It describes overexploitation as occurring when groundwater abstraction exceeds recharge, suggesting first that there is a clear point at which an aquifer becomes “overexploited,” or “overabstracted” and second that this threshold can be quantitatively equated with the “recharge” term of the mass balance. There are many variations of this storyline. In some cases, the statement is just flatly wrong: “If groundwater abstraction exceeds the natural groundwater recharge for extensive areas and long times, overexploitation or per- sistent groundwater depletion occurs” (Wada et al. 2010). But many formulations, implicitly or explicitly, equate overexploitation—or even the fact that water tables are falling—with abstraction exceeding recharge, indirectly suggesting that, as there is no overexploitation when pumping less, this is therefore allowable. In the Arab region “limited renewable groundwater resources continue 1 Corresponding author: UMR-Geau, Institut de Recherche pour le D´ eveloppement (IRD), 361, rue JF Breton, BP 5095, 34196 Montpellier Cedex 5, France; (33) 4-67-16-64-81; francois.molle@ird.fr Article impact statement : Displaces the storyline that overexploitation occurs when groundwater abstraction exceeds aquifer recharge. Received November 2022, accepted February 2023. © 2023TheAuthor. Groundwater publishedbyWileyPeriodicals LLC on behalf of National Ground Water Association. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. doi: 10.1111/gwat.13299 to be exploited at an unsustainable rate, exceeding nat- ural recharge rates” (ESCWA 2022). “Of Mexico’s 653 aquifers 101 are considered to be over-exploited, mean- ing that their net annual extraction exceeds their natural recharge” (World Bank 2009). “‘Overexploitation’ of an aquifer is a term applied to a physically unsustainable situation in which the extraction of groundwater exceeds replenishment (recharge) within a given area over a given period of time” (Pahuja et al. 2010). “Exploiting ground- water resources at a faster rate than recharge has led to widespread “overdraft” and falling water tables in many parts of the world” (Jones et al. 2011). “In many places we are extracting groundwater faster than it is being replen- ished by natural or managed recharge. This overdraft is driving groundwater depletion, or a diminishing volume of water in aquifers” (Richter and Melissa 2022). A perusal of the policy literature, as well as scientific articles, yields innumerable similarly ambiguous statements, such as, “we need to align use with recharge,” or to “restore the balance between abstraction and recharge,” directly or indirectly suggesting that abstracting less or as much as the aquifer recharge is the right and “safe” thing to do. Denouncing the flawed nature of these statements reminds us of the debate on the “budget myth” (Brede- hoeft 1997, 2002) and associated misconceptions about “safe yield” (Sophocleous 1997). It is well understood by hydrogeologists that any pumping from aquifers induces after some time and some stock depletion (and notwith- standing the possible fluctuations generated by hydrologic variability) a new state of equilibrium where abstrac- tion results in the “capture” of specific portions of both the recharge and the “natural” discharge of the aquifer to recipients like rivers, lakes or the ocean (Pierce and Cook 2020). Abstracting the same volume as the recharge actually draws all outflows to zero over time, with very drastic impacts on surface water and ecosystems and a spatial/social reallocation of the resource. More gener- ally, no continuous abstraction is without effect and its desirability and soundness must be assessed based on a consideration of what these effects are and who is affected and how. NGWA.org Groundwater 1 17456584, 0, Downloaded from https://ngwa.onlinelibrary.wiley.com/doi/10.1111/gwat.13299 by Institut De Recherche Pour Le Developpement, Wiley Online Library on [23/02/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License