Hydrology and Earth System Sciences www.hydrol-earth-syst-sci.net 1027-5606 1607-7938 7 3 2003 10.5194/hess-7-297-2003 http://www.hydrol-earth-syst-sci.net/7/297/2003/ http://www.hydrol-earth-syst-sci.net/7/297/2003/hess-7-297-2003.html http://www.hydrol-earth-syst-sci.net/7/297/2003/hess-7-297-2003.pdf 297 303 0000-00-00 The use of hydrological and geoelectrical data to fix the boundary conditions of a ground water flow model: a case study M. Giudici M. Manera E. Romano Università degli Studi di Milano, Dipartimento di Scienze della Terra, Sezione di Geofisica, via Cicognara 7, I-20129 Milano, Italy Email for corresponding author: Mauro.Giudici@unimi.it To assess whether the hydrometric level of an artificial lake in a quarry near Milan (Italy) could be assigned as a Dirichlet boundary condition for the phreatic aquifer in a fine scale groundwater flow model, hydrological measurements of piezometric head and rainfall rate time series have been analysed by spectral and statistical methods. The piezometric head close to the quarry lake proved to be well correlated with seasonal variations in the rainfall. Furthermore, geoelectrical tomography detected no semi-permeable layer between the phreatic aquifer and the lake, so the contact between surface and ground water is good. Finally, a time-varying prescribed head condition can be applied for ground water flow modelling.</p> <p style="line-height: 20px;"><b>Keywords: </b>ground water flow, boundary conditions, surface and ground water interactions, geoelectrical tomography, statistical analysis.