Groundwater dynamics due to general stream fluctuations in an unconfined single or dual-porosity aquifer subjected to general areal recharge

•Residue theorem and convolutional integral are used to obtain solutions.•The solution is applicable to many river-aquifer systems.•Effects of stream stage hydrograph on the head in a river basin aquifer are explored.•Effects of recharge in a fractured reservoir on its boundary depletion rate are investigated.•Guidelines for aquifer parameter estimation are presented.