ARTICLES

The Need for Borehole and Pump Installations Is Growing Fast

At one time, for a property owner to have access to a source of water, other than that provided by the local municipality, might have been considered a luxury. In recent years, however, this has become more of a necessity. The need does not only arise because the demand for water by domestic, commercial, and industrial consumers and the price it commands have continued to escalate. The radically diminished reserves are now being further depleted by the increased frequency of drought in a country much of which is already semi-arid. As a result, it may be time for more South Africans to consider investing in a borehole and pump installation.

There are a number of stages in the process and the starting point will be to arrange for an expert to conduct a hydrogeological survey. The objectives of the survey are fourfold, the first being to establish the likely presence of subterranean water at the designated site. Thereafter, the surveyor’s task will be to assess the approximate depth at which the aquifer is located, the potential yield as compared with the homeowner’s estimated needs, and the likely quality of the water. Much of this information will be obtained from existing records as well as a visual inspection of the terrain. Based on the findings, an estimate for the cost of drilling the borehole and the pump installation can be calculated.

Sometimes, there may be existing geological data from a previous survey while a successful drilling on a neighbouring property can also be a good indication. Nevertheless, it would be ill-advised to proceed purely on the word of a driller and it should also be born in mind that a quote will stipulate the maximum depth that will be drilled, and any further drilling will incur an additional charge per metre.

Assuming that the survey yields positive results and that these are confirmed by the drilling, the quality of the work performed and the equipment supplied are vital to the long-term performance of boreholes and pump installations. The latter are of two types, according to whether they are designed to operate submerged or mounted above ground. Of the two, the positive pressure applied by submersible models is more effective than negative pressure applied from above and they also consume less electricity.

When choosing the correct size pump for borehole installations, this must be based upon the total head of pressure to be overcome. This will be determined from the depth of the drilled portion plus the height of any vertical piping that may need to be installed above ground. Any horizontal piping needed to transfer water to a storage tank, however, does not add to the head of pressure and will, therefore, have no influence on the size of the pump required.

Any water treatment required will depend upon the intended use for the pumped water. For tasks such as cleaning cars and driveways, irrigating the garden, and topping up the pool, the underground supply may be adequate without further treatment. If it is required for drinking purposes, however, the company responsible for drilling the borehole and the pump installation should be able to test the water and determine the type of treatment plant that will be necessary.