Wellspring
Africa's Hand Powered Percussion Drill Cost Comparisons Between Hand Dug and Drilled Wells In the following examples we are using data collected in Liberia in 1986 and again in Nigeria in 1999. The hand dug technique in this example is the simplest design possible. We are assuming a well that is being built in stable soil which does not require a casing for the drilling or scaffolding for the digging. We are also assuming low labor costs, $5-a-day for trained technicians and $2-a-day for general laborers. (The lower wage actually favors the hand dug method since it is more labor intensive.) We will first list the basic costs for a single well and then list the costs
for twelve wells, assuming that the tools will make twelve wells before needing
replacement. BASIC DRILLING/DIGGING TOOLS
LABOR FOR DRILLING/DIGGING 45-FOOT WELL
DRILLING/DIGGING 12 WELLS
When it comes to finishing the well, there are many other savings to be
found. In the following example, we will assume that, to provide for a long
lasting and safe well, the hand dug well will have the minimum of protection in
the form of a raised cement lid and cement rings to line the well at the water
table only. The drilled well will have four-inch plastic PVC casing and a
concrete platform. MATERIALS FOR FINISHING ONE WELL
LABOR FOR FINISHING ONE WELL
FINISHING 12 WELLS
If we add the totals for both digging and finishing the twelve wells, the grand total
looks like this: DRILLING AND FINISHING TWELVE WELLS
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