Author(s)

J. D. Martínez-Nájera1, C. Cruickshank-Villanueva2 & M. Berezowsky-Verduzco2

Abstract

A mathematical model to evaluate coupled supply systems of rivers and aquifer types is presented; it is applied in the qualitative and quantitative estimation of extraction effects on the rivers and related aquifers under different hydrologic situations, with the purpose of determining the supply potential of the system. The model consists of the conceptual and numerical coupling of two structures that take into account different aspects of the systems under consideration. The first is for analyzing free-surface flow, and the second to carry out the analysis of flow in each one of the aquifers of interest for evaluation purposes. The coupling process occurs in iterative terms, the numerical implementation is realized by means of MODFLOW and ISIS. The approach is applied to the Papagayo River and the aquifers located in their river beds, in Guerrero State, México. The model is consistent with the field observations and numerically demonstrates that the system is able to yield the required volume by the aquifers and directly from the river. Keywords: river-aquifer coupled systems, equations of Saint-Venant, balance of flow in aquifers and Darcy’s law. 1 Introduction The flow of water in streams and aquifers follow its own field equations of balance of mass, energy and constitutive relationships, each system is related with the other by coupling terms. The purpose of the work is to present an approach to evaluate the dynamic of rivers and aquifers as supply systems under realistic conditions; the numerical implementation is carried out by using

Keywords

river-aquifer coupled systems, equations of Saint-Venant, balance offlow in aquifers and Darcy’s law