ABSTRACT
Seepage refers to local waterlogging problems caused by groundwater inflow from a higher lying outside source. The causal groundwater flow is referred to as the seepage
.flow and the affected area as the seep zone. The source may be a nearby hill range but also a higher lying terrace. The scale can be a rather small and local (scattered seep spots of < 0.5-1.0 ha each at the foot of a slope) but also large and regional (seepage into a valley from a surrounding mountain range). Seepage is a natural phenomenon as in all the above examples but may also be man-created (seepage from an elevated canal or reservoir, seepage from an upslope irrigated area, seepage into a deep lying polder, etc.). The distance between the source and the seep area can be small (< 100 m to 1 km) but also quite large (> 10 km) while the seepage flow may travel through various layers (for regional seepage flows easily up to 50-100 m depth). Diagnosis of seepage problems therefore often requires considerable insight into the local and regional geohydrologcial conditions.
