Seepage from channels and ponds with impervious boundary walls extending below floor level

The steady-state seepage after long times from flat-bottomed channels into “Green and Ampt” type soils is analysed using the method of conformal transformations for the case of an impervious boundary wall extending below floor level. Relationships, expressed in dimensionless form, are given showing the dependence of the seepage rate on the depth of the boundary wall and soil hydraulic properties. Similar relationships, obtained by an electric analogue that approximated to the hydraulic situation, are presented for the case of a circular pond with an impervious boundary wall. These relationships are useful not only for estimating the seepage from channels and reservoirs but also for analysing results from infiltrometer rings.