SEEPAGE FROM A PARTIALLY PENETRATING. STREAM OF FINITE WIDTH

Abstract

For a partially penetrating stream in an unconfined aquifer, the reach transmissivity increases with increase in depth of water in the stream, decreases with increase in length of aquifer boundary and increases tending to constant value with increase in stream width. A rigorous analytical solution for steady seepage from a trapezoidal stream/canal to an unconfined aquifer in which water table lies at a shallow depth has been derived using Zhukovsky function and Schwarz-Christoffel conformal mapping. Steady state seepage from a stream in a confined aquifer can be expressed as q = k F Ah = Fr Ah in which k is hydraulic conductivity, Ah is hydraulic head difference measured at a piezometer in the vicinity of the stream, and F is a factor which depends on location of the piezometer i.e. distance of the piezometer from the stream bank and stream geometry i.e. cross section of the stream and depth of penetration of the stream. The above linear relationship between seepage and Ah is valid for steady state and confined flow condition.....