Determination of deep tubewell spacing using aquifer characteristics and irrigation requirement

Abstract

Relationship between ~eep tubewell spacing in square grid tubewell layout and ~quifer characteristics has bsen studied using unsteady ground water flow equations. Both constant discharge and variable discharge condition,s were considered and unsteady ground water flow equations were solved with the help of an IB1 360 di~it81 computer. Comparison ~msmade between SP:1cinrc:of ~Iells subjected to mutual interference ann spacin{; of wells wj.thout interferenrJ8. Discharge, coefficient of tr~nsmissibility. stor~ge coefficient, time of pumping, static lift and peak monthly irrigation water requirement have been used as variable parameters. The ~tor~ge coefficient should be the determining factor in selecting deep tubewell spacinG whon ~Tlifer characteristics are considered. Soma amount of nutual interference is allowable in seJ..ectin~deAp tube"el:l spf'.cingf'r.dnon_interference spacing is not always practic~ble. It is not important to consider the variability OI well discharge due to increase in drswdown at the well with time, A design chnrt has boen devoloped for the selection of deep tc:;:;~:211 ~:"ncj n" f'''nRi deri n.CCflquifnr charr.cteristias rmd irrigation water requirement in square grid tubewell layout.