In the present work the physically based distributed rainfall–runoff modeling system, MIKE SHE, is used to simulate the surface runoff at a semi-mountainous impermeable area of Tavronitis River basin in Crete-Greece. The objective of this surface flow model is to develop an appropriate irrigation plan for olive trees. For the model calibration, a simulation time of one year (01/09/2000 - 31/08/2001) was considered, while for the model verification a two-year period (01/09/2001 - 31/08/2003). During these periods river flow measurements were obtained at two specified locations. These measurements were employed as targets for calibration and verification of the surface flow model. After the successful calibration and validation processes, the 2D maps of the overland flow were produced. Using these maps, the locations of significant surface water accumulation in the study region and for a specific time period were identified. Next, these locations were proposed for the construction of potential small hydraulic structures (dam or/and reservoir), for covering the irrigation needs of olive trees in the study area.