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Professional Borehole Pump Testing and Installation is Important

It is no longer easy or wise to ignore the fact that we are facing a serious threat to the continued supply of potable water in South Africa. To help reduce that risk, some of the nation’s consumers are recycling their grey and black wastewater in order to reuse it, while others are resorting to harvesting rainwater in tanks as a hedge against the increasing threat of drought or simply to reduce their monthly water bills. In practice, much of the planet’s fresh water is to be found underground but can usually be accessed by a sufficiently deep well or borehole. In the latter case, professional pump testing and installation will be just as important as the initial hydrological survey and the drilling.

While pumping water with equipment located above ground is practised all the time, the equipment is best used when applying positive pressure to displace liquid rather than negative pressure to suck it in, especially if it has to be raised to a considerable height. To extract water from a subterranean source would create pockets of air that result in turbulence and the phenomenon known as cavitation that can severely damage the impeller blades.

As a consequence, when drilling a borehole, a submersible pump is required, as is thorough testing and professional installation. There is, however, a limit to the height to which a given submersible unit is able to raise water from the aquifer in which it is located. Technically known as the head, it is a measure of the pressure required to raise water to ground level added to any additional vertical distance traversed by pipes installed above the ground. It is this figure, combined with the desired flow rate, that will determine the most appropriate unit for use in any given site.

The surveying and drilling processes also require professional handling. The hydrologist will consult local ordnance survey maps (or OS maps) and the surrounding terrain to determine the best starting point and the probable depth of the shaft while, in addition to creating it, the drilling team will also insert a stainless steel liner to prevent contaminants from the surrounding soil entering the flow, before the installation and testing of the borehole pump can be undertaken.

The tests performed are necessary in order to confirm that the equipment is able to deliver both the pressure and the flow rate necessary to meet the requirements of the client.  In addition to thoroughly testing the performance of the borehole pump, the installation might also include adding a compact water treatment plant, a specially lined storage tank along with extra pipes and taps, if the client’s wish is to provide a primary or secondary potable supply for domestic use.

Whether for use in the suburbs or in a settlement or farm, remote from the municipal service, water is a precious commodity. Unfortunately, even though Mother Nature has an efficient means to recycle it, excessive and escalating human demands, combined with climate change has meant natural recycling is no longer sufficient and consumers must either reduce their usage or seek alternative sources.

For professional surveys, expert drilling, borehole pump testing and reliable installation of world-class products, more and more South Africans are relying on Water Pump Group.