Work

Water Resources Availability on a River Watershed in a Relevant Mineral Province (Minas Gerais, Brazil): An Integrated Approach to Water Resources Management

Year: 2025

Type: article

Abstract: The watershed of the Peixe River lies in central Minas Gerais state, close to Belo Horizonte city, a densely populated area. The area is located in the geological context of Quadrilátero Ferrífero, one of the most prominent mineral provinces in Brazil. To better recognize surface and groundwater availability, some methodologies have been applied to evaluate the minimal surface flow rates, groundwater recharge, and water reserves. The basin includes three main aquifer systems: Cauê (porous and fissured aquifer), related to iron formations; Gandarela, related to karst-fissured rocks; and Cercadinho, related to metapelite rocks. The Cauê aquifer presented the highest effective porosity and hydraulic conductivity. In contrast, the Cercadinho aquitard shows the lowest hydrodynamic parameters. Data between the years of 2004 and 2024 from 21 pumping tests from wells associated with the three aquifer systems were obtained to estimate the respective recharge rate. The recharge was evaluated by numeric recursive filter and recession-curve displacement methods. The recharge results with the numeric filter method showed underestimated values. Regarding the recession-curve displacement method, the results were more consistent with other studies in the surroundings. The average recharge estimated for the basin represents 24% to 54% of annual pluviometry in the hydrological periods of analysis. The recharge data were accounted for in the reserves calculation, including permanent and renewable reserves. Total permanent reserves were estimated to be 3.16 × 109 m3, including the prior aquifer systems of Cauê, Gandarela, and Cercadinho. The total mean renewable reserves of the basin were calculated to be 4.55 × 107 m3/year in the analyzed period. The high BFImax indexes found in baseflow separation, above 90%, suggest a relevant contribution of the karstic Gandarela aquifer on the watershed surface flow. Although in some years it has been concluded that groundwater exploitation outlines the renewable resources availability, in 2024’s scenario, the granted water volume was lower than the estimated availability and reserves. The best methodologies for coupling surface and groundwater are the Weibull distribution for reference surface flows and the recessive-curve displacement for baseflow separations. This research will be a contribution to water resources management strategies for regions with high population growth and water demand increase.

Source: Water

DOI: 10.3390/w17040532

Authors: Alex Rodrigues de Freitas, Rodrigo Sérgio de Paula, Isabel Margarida Horta Ribeiro Antunes

Institutions: Universidade Federal de Minas Gerais, University of Minho

Language: English

Topic: Water Quality and Resources Studies

Subfield: Water Science and Technology

Field: Environmental Science

Domain: Physical Sciences

SDG: Clean water and sanitation

Open Access status: gold

Estimated APC paid: $3,137