Author(s): Boris Lora-Ariza; Leonardo David Donado
Linked Author(s): Leonardo David Donado Garzón
Keywords: Hydraulic characterization Middle Magdalena Valley Pumping test Hydraulic conductivity
Abstract: In tropical countries, surface water has historically been prioritized over groundwater (MacDonald et al., 2012). However, recent decades have seen a marked increase in the demand for groundwater resources, underscoring the need for effective management of this resource (Dalin et al., 2017; Kurwadkar, 2017). To achieve sustainable management, it is crucial to characterize aquifer systems with hydrogeological potential. In Colombia, however, there is a notable lack of hydraulic data that would allow for an assessment of subsurface heterogeneity based on the spatial distribution of hydraulic properties. This study compiled available hydraulic data for the Middle Magdalena Valley in Colombia, encompassing 3519 groundwater points with at least one water level measurement. Of these, 3168 points (accounting for 90%) had only a single depth measurement, and only two points had more than 100 measurements. This highlights the absence of historical time series data for water levels. Additionally, 136 pumping tests were collected and reinterpreted using the methodology proposed by Renard et al. (2009). A regional-scale hydraulic characterization of the Neogene-Quaternary units in the Middle Magdalena Valley was performed. Based on piezometric data, a predominant south-to-north flow direction was identified, aligned with the topographic gradient, along with secondary east-west flows discharging into the Magdalena River. This pattern was validated using hydrochemical and isotopic data. A total of 512 analyses of physicochemical, microbiological, and/or isotopic samples were conducted as part of this research. Estimated hydraulic conductivity values ranged from 0.003 m/day to 154 m/day, with an average conductivity of 5.7 m/day for Quaternary units and 4.3 m/day for the Real Group, a Neogene formation, with the shallowest unit (Real U4) being the most hydraulically conductive.
Year: 2025