SO WHAT’S A WELL?

A well is simply a hole in the ground that reaches down to an

aquifer. Traditionally, people in the developing world have dug

wells by hand, which means that only the shallowest aquifers

can be reached; hand-dug wells rarely exceed 50 feet, and are

often left open, allowing run-off water and other contaminants

to enter the well from the surface. The shallow aquifers that

these wells draw from are vulnerable to pollution from agricul-

tural fertilizers, industrial waste, or seepage from nearby latrines.

With the right equipment, wells can be drilled to deeper, safer

water. A pipe and a pump are used to pull water out of the

ground, and a screen filters out any particles. Drilled wells are

lined with PVC or galvanized steel to protect them from pollu-

tion that could otherwise seep in. They are sealed systems, with

pumps that only allow water to flow out of the hole, to prevent

contaminants from being introduced from the surface.

OKAY... HOW DOES IT WORK?

Wells come in different shapes and sizes, depending on the

soil conditions and how much water is needed. In some areas,

wells need to be very deep to reach good water—sometimes

1,500 feet or more—and require powerful electric pumps pow-

ered by diesel generators. These wells are drilled in large com-

munities, and are often installed at a hospital or school. They can

produce hundreds of thousands of gallons in a day and serve

tens of thousands of people.

In the overwhelming majority of cases, wells don’t need to be

so deep; safe water is usually found within 100 feet of the sur-

face. For a well like this, a manual hand pump can be installed.

There are many kinds of hand pumps, some of which can pull

water up from a depth of 200 feet. While not as convenient as

an electric pump, a hand pump is usually a much more appro-

priate solution for a rural community, both culturally and

technologically: hand pumps use common, easily-replaceable

spare parts, and are simple for a village caretaker to maintain

with minimal skills and few tools. Except for the occasional

repair, it costs the community nothing to operate the well. Hand

pumps are cost-effective, and the pumps used at LWI’s wells

are proven to be robust and reliable under field conditions. A

single hand pump can easily provide water for a community of

500 people, but LWI teams regularly visit areas where two or

three thousand people rely on one pump, and more wells are

desperately needed.

courtesy of LWI. www.water.cc