Studies on groundwater recharge through surface drains

Abstract

A mathematical model is developed for the estimation of groundwater recharge through surface drains for both free flow as well as detained flow conditions. The Dupuit-Forchheimmer equation is solved using the Crank-Nicolson central finite difference scheme, to obtain the mound height matrix. The Gaussian elimination method was used to solve the matrix, to obtain the mound height at different radial distances across the drain. Various hydrogeological parameters like hydraulic conductivity, specific yield, etc. are determined by field investigations. Surface runoff available due to a particular rainfall event is correlated with recharge rate available in the drain. The model gives volume of water recharged for various rainfall events under different antecedent moisture conditions for both free flow and detained flow conditions. The value of recharge rate computed by using the model for a particular depth of flow in the drain is matched with the observed values. The model is more sensitive to change in the value of specific yield than hydraulic conductivity.

Prediction of overland flow and seepage zones associated with the interaction of multiple infiltration devices (cascading infiltration devices)

“…Simplified representation of a ground-water mound developed around an infiltration device alternative equations (e.g. Harr, 1991;Brutsaert, 2005;Singh et al, 2005;Cloke et al, 2006;Rushton, 2006). The height h can be estimated from h D h 0 C s n 5…”

“…The height h of the surface of the mound at any point in the subsoil can be modelled as a function of the distance and time from the device using a number of alternative equations (e.g. Harr, 1991;Brutsaert, 2005;Singh et al, 2005;Cloke et al, 2006;Rushton, 2006). The height h can be estimated from…”

Movement of Water Infiltrated from a Recharge Basin to Wells

“…Engineering considerations related to infiltration from ponds include pond design (Rao and Sarma 1981; Pettyjohn 1981; Zomorodi 1988; Bouwer 2002), the effects of clogging (Moravcováa et al 1968; Behnke 1969), and air entrainment (Christensen 1944; Bianchi and Haskell 1966; Heilweil et al 2004) on infiltration rates, and mounding of water at the saturated zone (Hantush 1967; Marino 1974; Singh et al 1976; Bouwer and Rice 1989). In early applications, comparatively shallow depths to water were favored when locating recharge ponds intended to recharge water table aquifers.…”