INFILTRATION WELLS AND GALLERIES: EXISTING PRACTICES AND DESIGN CRITERIA

Abstract

Water is vital for life. Development of any area without water is unthinkable. Drawing water from surface sources is more traditional than tapping groundwater sources. Surface water, however, can not be used without treatment. Groundwater is generally safe to drinking if it is not affected by any pollutional sources. Now-a-days the developments of new townships are mostly based on groundwater sources. The water quality of infiltration wells located adjacent to Ganga river and Upper Ganga canal in Hardwar and Rishikesh have been studied alongwith adjacent surface waters. Both surface and ground waters enter into an infiltration well primarily from bottom. Some water also seeps through weep holes provided in the well-wall. In the present investigation eight wells were found to be almost entirely fed by nearest surface water while two also receive considerable amount of ground water. All the infiltration well waters were found to be fit for drinking (with chlorination in some cases), while respective surface waters contained unacceptable amounts of total coliforms, turbidity, and suspended solids. Natural material acts as an effective filter in purifying surface waters at no cost. This makes water collection simpler and economical as treatment involving coagulation-flocculation-settling and filtration is avoided.