Addressing Data Scarcity and Structural Uncertainty in Groundwater Recharge Assessment: Refining the Recharge Model in the Chiquitano Dry Forest (Eastern Bolivia)

Abstract

ABSTRACT Accurately assessing groundwater recharge is crucial for sustainable water management in regions with limited data and high hydrological complexity. Focusing on the El Sutó spring (eastern Bolivia), this study integrates a field‐informed conceptual model with three numerical approaches—USGS Soil‐Water Balance (SWB‐USGS), a Simplified Water Balance driven by FLDAS (SGWB‐FLDAS), and Seasonal WetSpass (SeasonalWS)—to refine the representation of recharge processes in a tropical dry setting. Approximately 16.4% of annual rainfall percolates beyond the root zone, with rainy‐season recharge ~6.8× higher than in the dry season. Daily‐scale SWB‐USGS better captures short‐lived, high‐intensity events, while monthly and seasonal models smooth episodic peaks and emphasise long‐term spatial constraints. Cross‐model inconsistencies are used constructively to iteratively update the conceptual model, constraining structural uncertainty. Proxy consistency checks using water‐table fluctuations and observed intake discharge support the process realism of the refined framework. The multi‐model strategy advances transferable understanding of recharge in tropical dry ecosystems and offers practical guidance for water‐scarce contexts.