In hydrology, throughflow, a subtype of interflow (percolation), is the lateral unsaturated flow of water in the soil zone, typically through a highly permeable geologic unit overlying a less permeable one. Water thus returns to the surface, as return flow, before or on entering a stream or groundwater.[1][2] Once water infiltrates into the soil, it is still affected by gravity and infiltrates to the water table or if permeability varies laterally travels downslope.[1] Throughflow usually occurs during peak hydrologic events (such as high precipitation). Flow rates are dependent on the hydraulic conductivity of the geologic medium.[1]
- ^ a b c Fetter, C. (2001). Applied Hydrogeology. New Jersey: Prentice-Hall. p. 41. ISBN 0130882399.
- ^ Selby, M. (2005). Hillslope Materials and Processes. New York: Oxford University Press. p. 216. ISBN 0198741839.