ARTICLES

Preliminary Borehole Surveying is Essential to Assess the Potential Yield

Next to oxygen, it is water and not food that is essential to our survival. It is, therefore, an alarming fact that the reserves of this life-giving liquid which may be considered safe to drink have been dwindling steadily for decades, as the global population has expanded, and we have found ever more ways in which to utilise it for purposes other than maintaining life. It is perhaps ironic that, although oceans cover more than 70% of the planet’s surface, only around 3% of the earth’s total water resources are in the form of fresh water. Much of it is to be found underground and, consequently, borehole surveying is becoming increasingly important for the detection of subterranean aquifers in order to access their content.

While it may seem that lakes and rivers are fairly abundant other than in desert areas, their contents account for less than one-third of a percent of the total fresh water supply. Of the remainder, almost 70% is trapped in glaciers and icecaps and so largely inaccessible. As a result, the balance of just over 30% that occurs as groundwater is a crucially important resource and one that needs to be exploited with great care, and with due concern for the needs of future generations.

Naturally, borehole surveying is likely to remain the only option for those who manage our farms or who are living in remote locations beyond the reach of municipal supplies. For the inhabitants of coastal towns, there is now the prospect of more economical desalination technology that could be used to bolster their local reserves. However, in the light of the rising cost and frequent rationing of these supplies, a growing number of those residing in the suburbs of inland cities and towns are now turning to groundwater sources in order to reduce dependence upon their local service providers.

What Does Borehole Surveying Entail?

There are a number of procedures that are commonly applied for this purpose and overall, there results are generally quite reliable, although it is not always possible to predict exactly how deep it may be necessary to drill before intersecting an aquifer or precisely how large the long-term yield of the drilling exercise may be. The methods used for this purpose today, however, have progressed well beyond the use of the twitching willow, peach or witch-hazel twigs still favoured by so-called water diviners or dowsers.

Modern hydrologists rely instead upon the geology of the local and surrounding areas when surveying for borehole drilling sites. Geological maps provide information regarding the location and length of sedimentary rock layers that provide conduits for underground freshwater streams, while any existing wells in the neighbourhood also provide a valuable clue and the presence of a thriving water-loving plant such as a willow tree in the target area offers another.

To the prospective well-owner, the services of an experienced profession skilled in the practice of borehole surveying are as essential as those of an expert drilling team. Both should form part of an itemised quotation that also details the maximum depth of drilling before additional costs may be incurred. Professionalism and expertise form the core of borehole surveying and drilling by the Water Pump Group. For more information on our services, please feel free to contact us today.