Abstract
Ground-water is an important source of water supply throughout the world. Transmissivity and Storage Coefficient are two important parameters in ground-water problems, Theis technique was used for the determination of these parame-ters. For this purpose data of 15 pumping wells were analysed and it was concluded that Theis technique was the best method for this purpose especially when the pumping wells were fully penetrating.
INTRODUCTION
Transmissivity (T) and storage coeffi-cient (S) of an aquifer are of fundamental importance in ground-water problems. In-formation about the quantity of water which could effectively be stored and transmitted by an aquifer can be obtained by transmis-sivity and storage coefficient. This informa-tion may be used as guidelines in installation of tubewells for irrigation, drainage, indus-trial and municipal supply schemes, In Pak-istan, ground-water contribution towards the total demand of the country is not much ap-preciated. Therefore, an extensive develop-ment of ground-water supplies by means of pumping wells is highly desirable in order to Meet the increased demand of this essential article of daily use, There were several methods available for the determination of transmissivity and storage coefficient, but the selection of a proper method could facilitate an economi-cal and reliable estimate of the parameters. Theis (1935) developed a non-equilibrium well formula for the calculation of T & S. This formula took into account the effect of time of pumping on well yield. Cooper and
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Jaccob (1946) presented a modified non-equilibrium formula which was valid only for which "U" < 0.05, where U is an integral ar-gument. Chow (1952) developed a method of solution with the advantage of avoiding curve fitting and certain limitations. Todd (1980) reported that T & S could best be determined from pumping test of wells or from ground-water fluctuations in response to atmospheric pressure or ocean's tide vari-ations. Linsley et al. (1982) quoted use of "Dupuit" equation for the determination of T which was obtained from the equilibrium hydraulics of wells.
MATERIALS AND METHODS
In this study, Theis method was used for determination of T & S. For this pur-pose, the data of 15 pumping tubewells were obtained from NASA (Water and Sanita-tion Agency), Faisalabad, which were in-stalled at different locations in Faisalabad region. Of these, only live representative pumping tubewells have been discussed here.
