Estimating recharge rates with baseflow separation in the Ibicuí Watershed (South America)

Published
2016-02-01
DOI: https://doi.org/10.14295/ras.v29i3.28487
Keywords: Base flow. Eckhardt’s filter. Aquifer recharge. Escoamento de base. Filtro de Eckhardt. Recarga aquífera.

    Authors

  • Camila Dalla Porta Mattiuzi Companhia de Pesquisa em Recursos Minerais - CPRM
  • Roberto Kirchheim Companhia de Pesquisa em Recursos Minerais - CPRM
  • Walter Collischonn Instituto de Pesquisas Hidráulicas - IPH/UFRGS
  • Fernando Mainardi Fan Instituto de Pesquisas Hidráulicas - IPH/UFRGS

Abstract

This study aims to estimate the groundwater recharge rates in the Ibicuí Watershed, in the state of Rio Grande do Sul, using baseflow separation method. The watershed’s main aquifer is the Guarani Aquifer System, in its confined areas (West) and outcrop (Central). The baseflow separation was made with the Eckhardt (2005) numerical filter, with historical streamflow data released by the National Water Agency. The recharge estimates were compared with the geological, hydrogeological and soil found in the study area. Recharge rates ranged from 88 mm/year to 378.7 mm/year (13% and 47% respectively of the effective precipitation in the sub-watersheds, and 6% to 21% of total precipitation). The results showed that the higher recharge rates were found in the geological units with higher transmissivity and more permeable soils, and with higher average precipitation. On the other hand, sub-watersheds with low recharge rates showed permeable geologic units and crystal units, soils with high clay content and low average precipitation.

How to Cite
Mattiuzi, C. D. P., Kirchheim, R., Collischonn, W., & Fan, F. M. (2016). Estimating recharge rates with baseflow separation in the Ibicuí Watershed (South America). Águas Subterrâneas, 29(3), 285–300. https://doi.org/10.14295/ras.v29i3.28487