Impact of spatio-temporally variable recharge on the characterization of well capture zones

A synthetic study, using a Monte Carlo approach, was conducted to investiga- te the impact of spatially variable recharge on the uncertainty of a well capture zone. The impact of spatial recharge variability was found limited for a moderately heterogeneous transmissivity field. Only recharge variances that are unrealistically large for a humid, temperate climate (e.g. in north, northwest and central Europe) yielded an important additional uncertainty in the estimation of the well capture zone. However, the uncertainty in the mean recharge was found to have a strong influence on the simulation results. It is suggested that estimation of the mean recharge for one or a few zones may suffice for the joint inverse estimation of transmissivities and recharges.