Calibration and Reliability in Groundwater Modelling: Credibility of Modelling

(Proceedings of ModelCARE 2007 Conference, held in Denmark, September 2007). IAHS Publ. 320, 2008, 182-188.

Evaluation of the hillslope-storage Boussinesq model with leakage

S. Broda¹, C. Paniconi² & M. Larocque¹

1 Centre de recherche pour l’Étude et la Simulation du Climat à l’Échelle Régionale,
Département des sciences de la Terre et de l’atmosphère, Université du Québec à Montréal (UQAM),
Case postale 8888, succursale Centre-ville, Montréal (Québec) H3C 3P8, Canada

stefan@sca.uqam.ca

2 Institut national de la recherche scientifique – Centre Eau, Terre & Environnement (INRS-ETE),
490 rue de la Couronne, Québec G1K 9A9, Canada

Abstract The hillslope-storage Boussinesq (hsB) model (Troch et al., 2003) has been extended to allow for leakage through a hypothetical aquitard at the hillslope bottom. A leakage term has been incorporated by extending the mass balance and combining it with the Boussinesq equation. To evaluate the extended hsB model, simulated water table levels are compared with results of a three-dimensional surface–subsurface flow model solving the Richards equation. Numerical experiments are performed on an inclined straight hillslope. Results from the extended hsB model are in reasonable agreement with those from the benchmark model, indicating that the hsB model can be used to simulate recharge to a deep semi-confined aquifer. The leakage rates calculated by the 3-D model show significant spatial variability, indicating the requirement for further extension of the hsB model to account for spatially distributed leakage.

Key words subsurface flow; hillslope drainage; Boussinesq equation; leakage