PERFORMANCE ASSESSMENT OF A RADIAL COLLECTOR WELL NEAR A STREAM

Abstract

Traditionally, water supplies for drinking or industrial uses have been drawn from rivers, streams, and from natural or artificial collections of water. The systems of tapping under-ground water have been tube wells (vertical well), infiltration galleries, and radial collector wells. Vertical wells are generally suitable in a thick aquifer and it can tap water from an aquifer lying at greater depth. An infiltration gallery is a horizontal perforated pipe or conduit suitable for tapping water from a shallow aquifer. Infiltration galleries are generally laid near a stream or river to intercept infiltration water from the river. Infiltration galleries may be laid in different alignment, such as parallel or perpendicular to the stream or a river. A radial %.,olle‘.,toi well (RC W) c,onsisis of a IfufIIU I of ituriconitd performed pipes laid in an aquifer and connected to a vertical cylindrical caisson, plugged at the bottom end. These wells are particularly suitable for shallow highly permeable thin aquifers in which vertical wells have low yields due to the limited drawdown. RCWs have significantly longer well screen, which is exposed to the aquifer, and produce large quantities of water under the moderate drawdown conditions. A radial collector well with one or two collinear laterals can be treated as a horizontal collector pipe or an infiltration gallery. However, in case of multiple laterals in a radial collector well, the laterals interfere with each other, and hence it is important to provide non-perfortaed portion of pipes near the caisson.