Classification of wells

CLASSIFICATION OF WELLS

The wells may be classified as

i.                   Open wells

ii.                 Tube wells

i.                   OPEN WELLS or DUE WELLS

Smaller amount of ground water has been utilized from ancient times by open wells. They are generally open masonry wells having compensatively higher diameters and are suitable for low discharge (18m³/hr). The dia of open wells may be 2-9m and they are generally less than 20m in depth. The walls of an open well may be built by brick or stone masonry or precast concrete rings.

The open wells may be classified into the following 2 types

i.                   Shallow wells

ii.                 Deep wells

The nomenclature of shallow and deep is purely technical and has nothing to do with the actual depth of the well. A shallow well might be having more depth than the deep well.

YIELD OF AN OPEN WELL

The term yield of the well is used to indicate the rater of with drawl of water without causing failure of well. It is the rate at which a well can supply the water.

The factors which influences the yield of an open well are:

1.     Well dimensions

2.     Location of nearby wells

3.       Porosity of aquifers

4.     Quantity of water available in aquifers

5.     Slope of water table

  6.     Coefficient of permeability of soil.

7.     Rate of pumping water.