Overview |
There is water at some depth almost everywhere
beneath the earth's surface. A well is a dug or
drilled hole that extends deep enough into the ground to
reach water. Wells are usually circular and walled with stone,
concrete or pipe to prevent the hole from caving in.
They are sunk by digging or drilling through one or
more layers of soil and rock to reach a layer
that is at least partially full of water called an
aquifer. The top of the aquifer, or the level beneath
which the ground is saturated with water, is called the
water table. In same areas there is more than one
aquifer beneath the water table. Deep wells, such as those
sunk by large motorized equipment, can reach and pull water
from more than one aquifer at the same time. However,
this manual will only discuss sinking wells to the first
usable aquifer with hand-powered equipment.