7 Things to Consider when drilling a Borehole

In today’s uncertain times having a borehole is no longer a luxury. With the threat of global warming and the escalating decay of our water infrastructure, our access to clean, potable water is in jeopardy. Internationally, there has been a move towards private water supply and South Africa is no exception. Together with the trends to self-sufficiency, like solar power, boreholes have become increasingly more important.

As the demand for boreholes increases so too does the availability of service providers. The market is perceived as been a lucrative one and newcomers are continuously entering the market. But not all boreholes are drilled equal. A borehole should last anything from 20 – 50 years provided the construction is structurally sound. Ground conditions change from one borehole to another hence each borehole is unique.

As a consumer it is difficult to know if you have selected a competent service provider with the right level of skill. Drilling a borehole today is an investment which increases the value of your property. Although initial costs of drilling and installing pipes and pumps may be high, there are many long-term benefits to having your own water source. At prices ranging from R80 000 to R120 000, and sometimes more depending on your unique requirements, you want to be sure that you have the right company drilling your borehole.

  1. The first thing you would like to know is if the company belongs to an industry association like the Borehole Water Association of South Africa. Although the industry association or organisation has no legal hold over the service provider, their members are expected to abide by the regulations and standards of the association. The Borehole Water Association will advise you on what to expect when drilling a borehole and if a dispute should arise between you and the service provider, they can offer some intermediary assistance.
  2. As the say in real estate, “Location, location”, so it is with borehole drilling. It would be a good idea to do some inquiries with your neighbours to see how many people have a borehole and the yield and depth of these boreholes. When interacting with the borehole company try and gauge their level of experience in your area and what they expect in terms of yield and depth. The final port of call would be a geohydrologist or geophysicist. They will use instrumentation, topology and mapping to mark out the point that has the best potential for intercepting water. Many drillers have large heavy equipment and can only access the driveway of the property hence many surveyors/diviners mark a point on the driveway. Keep in mind that Blue River Drilling SA uses the Armidilo that can access those hard to reach places. We go where the water is.
  3. Once you have found you spot, you now need to find the driller. As mentioned, the Borehole Water Association can provide references after which you can ask the driller for some customer references. It is better to get references dating a year or more as this will give you an idea of how the borehole drilled has stood the test of time. The driller’s level of experience is also important, so you would want someone who has a good knowledge of drilling and the various ground formations they may have encountered. It is also important that the equipment is well kept and reliable.
  4. Does size matter? More and more small drill rigs are entering the market. These machines can make the difference, provided they live up to their claims. A domestic borehole will on average be about 60m – 120m. It is rare to go deeper than this. A traditional rig will make these depths with very little effort. Not all small rigs can do these depths. Some are only designed to go through soft sands and soils and when they reach the bedrock the driller struggles to go further. Some of the small rigs are confined to drilling a small diameter, less than 6”, where only a smaller non-standard pump can fit. In some cases, the diameter is too small to fit borehole grade casing and over time the borehole collapses as it did require the casing in order to remain stable. It is important to know what the capability of the machine is and to have this in writing so if the hole is not to standard you have recourse. The Armidilo designed, build and operated by Blue River Drilling SA is able to drill a standard borehole of up to 8” and a depth of 160m. The standard diameter for a domestic borehole is 152mm (6”). 
  5. A well constructed borehole often requires casing, either steel or UPVC. The inclusion of casing in a borehole can almost double the cost of the borehole that was initially quoted. This is one reason why a driller should have some knowledge of the area as he will be able to advise beforehand if there is a chance of having to case the complete borehole. Most drillers may only mention this in passing as the costs are that much higher for a fully cased borehole and this might deter the client. When it comes to casing, he may make the decision to forgo the casing only to find that in 2 or 3 years the borehole has collapsed. It is strongly advised that you discuss the need for casing with your service provider. It is far better to take another 2 or 3 months to save for the casing than to forgo this important part of the borehole construction. Also remember to discuss the pros and cons of steel casing and UPVC casing. 
  6. It is extremely difficult to predict the exact ground formation that the driller will encounter while drilling your borehole. Even though the borehole site survey can give you a good indication, there is still a possibility of Mother Earth surprising us. A very hard and abrasive rock formation can attract a drilling surcharge to make up for the wear and tear on the bit and the additional diesel used. Soft sands or clay might call for foam drilling which will also attract costs for the additives. Once again an experienced driller should be able to advise in advance if there will be any additional drilling costs over and above the standard rate. 
  7. Drilling is messy and noisy. The equipment and drilling process can be dangerous and cause injury. Remember to keep animals and children away from the equipment and for peace in the neighbourhood give your neighbours a head’s up that you will be drilling a borehole. And remember, for your safety and the safety of our crew please adhere to the rules of social distancing.

 

For further information you can reach us on 083 446 4226 or betty@brdsa.co.za

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