Water borehole is commonly used around the world. But do you know the drilling process? Here are the 4 stages of Water borehole drilling.
- Pre-drilling
When drilling Water borehole, it is usual to start the process with a geological survey and vertical electrical sounding to locate water underground. The VES sounding attempts to map the availability of water by taking resistivity measurements using probes at a set distance apart.
In most countries, a borehole drilling permit and environmental report is required before commencing drilling.
- Drilling
A drilling rig is required for the drilling. As the drill progresses into the ground, extra drill rods are added until eventually the drill reaches the required depth.
A geologist is needed to supervise the drilling process; always engage qualified geologist and personnel. They ensure boreholes are drilled straight for correct procedures like steel casing and gravel filter pack fitting are followed.
For maximum water yield, boreholes must be developed and test pump conducted after 24 hours to pump out dirty water and to check what yield the bore-hole can supply before samples are taken for bacteria and chemical analysis.
- Pumps
The type of pumps may vary from mains powered, solar powered and wind powered depending on the availability of power and intended use of the borehole. In Africa, sunshine is abundantly reliable and predictable making solar energy a low cost.
For example, Osiligi Charity Projects, a non-governmental organization running charity projects in rural Kenya, recently sunk a borehole in a school it manages, to run throughout on green technology so they settled for solar powered Lorentz pumping system.
Piping is greatly determined by the intended use like irrigation, home supply, distribution or charity.
- Cost of drilling a borehole
Borehole drilling in every country has unique processes involved from conception to delivery and the combination of factors that impact the components and processes used will almost always be different.
Therefore, borehole drilling cost is not a constant and specific amount on paper. A carefully calculated quotation must be drawn and particular costing needs affected by different conditions must be considered.
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