The Cost of a Borehole

A common question that we are asked is “How much does a borehole cost?” While this might seem like a straightforward question to ask, the answer certainly isn’t. It is the equivalent of asking how much a car costs.

The answer is dependent on various factors. What kind of car do you need? What do you want to use the car for? There isn’t a blanket price for a car, and likewise there isn’t one for a borehole either.

The cost of a borehole is largely dependent on its depth and the amount of casing to be used. The type of rock that we have to rill through also influences the price, as does the actual ground conditions.

While most people expect the easiest drilling to be into soft and loose geologies, the opposite is generally true. A great difficulty of the drilling process is to keep the borehole open during the process, which is made more difficult when the hole is collapsing in on itself because of unstable and loose ground.

We itemise all our quotes, however, in a logical manner that makes them easy to understand, so that the customer is aware of the costs at every stage of the project. A breakdown of the quote is detailed below for your reference.

The Cost of Mobilisation To and From the Site – And the Cost of Drilling

The cost of getting our equipment to your home or yard is usually based on the type of equipment needed (wheeled or tracked) and the distance we need to cover. The charge for drilling is per metre for different diameters. We usually start the borehole at a larger diameter, for example at 203mm, and this is drilled into solid rock to allow for the casing to be installed through the soft upper portions. It also helps to prevent collapse.

Most rock types are drilled at the same rate. Quartzite, however, because of its abrasiveness, is charged at a higher price, since it wears the drill bit down faster. Some loose ground conditions will also require a different drilling method, such as ODEX – but this is not commonly used in Gauteng.

Cost for Casing and Gravel Packing the Borehole

We charge per metre for the supply and installation of casing. Rest assured, however, that most boreholes in the Gauteng region only require steel casing through the soft weathered overburden, which is usually 12-24m, in order to secure the upper portions of the borehole from collapse.

Cost of Supply and Installation of Well Head

We install the purpose-built well head chamber (manhole) over the head of the borehole to allow access to the borehole and protect it from contamination. The boreholes are typically drilled in the driveway, so manholes are made to withstand traffic.

Cost of Developing and Flushing of the Borehole

An important procedure to undertake once the borehole is drilled and completed is to develop / flush the borehole clean of the drilling debris. Much of the rock fragments can get caught up and block the cracks, thereby blocking water from entering the hole. We take care of this aspect for you.

Cost of Site Clean Up

Drilling is a messy business, as the soil, mud and rock fragments that accumulate can be a huge mess. We protect your property by placing a plastic liner down under the rig before we even start drilling. The final clean up takes place when the rig moves off the borehole, and we will ensure that your property is clean of any debris when we finish the project.

Cost of Chemical Analysis

If the intention is to go off the water grid and use the borehole for human consumption, it is highly advisable to get a representative sample of the groundwater analysed at an accredited laboratory. You want an accurate reflection of the water quality, hence the water sample should be collected after purging of the borehole of at least 3 times its volume. We typically collect the water sample during the Yield Testing. The sample needs to get to the lab within 5 hours of collection. Two samples should be collected – one in a sterile bottle for Microbial counts and the other for macro & micro elements. The cost of the chemical analyses is made up of transport costs (getting the sample to the lab -Pretoria0; lab analytical costs, qualified interpretation & reporting.

The test for potability is known as the SANS-241 test which analyses for major cations & anions, selected micro elements, selected metals and microbial counts. Make sure that the person who interprets and reports on the chemistry has some form of qualification to interpret the results.

Cost of filtration & treatment

The lab results will dictate what if any treatment is required and hence the cost there of. Most groundwater in the greater Gauteng area is fit to drink without any treatment, bar particulate filtration and neutralizing of the water. Whilst most of the water is Class 1 drinking water (best quality), it does have a tendency to be aggressive. Simply explained, aggressive water can lead to corrosion of your plumbing and reticulation piping and pinhole leaks may from after many years, resulting in you having to chop out and replace piping in walls and floors of your home. Something you definitely do not want. So we analyse your water for corrosivity and install a neutralizing filter which treats the problem before it starts. You should have the corrosivity re-tested every 3-4 years.

The Cost of a Pumping System

The pumping system includes the cost of the borehole pump (submersible) which is installed down the borehole and if sized, installed and utilized correctly will work without any issues for years on end. The size and duty of the submersible pump is determined from the results of the yield test. The marriage between the borehole and the pump must be a “happy” one or problems will appear in time which will incur costs that were avoidable from the start.

From the borehole the water is pumped into a holding tank (Jo-Jo) where a significant volume (usually between 1000 – 10 000L) is stored. A pressure pump, which is connected to the home reticulation system draws water from the tank which passes through the filter/treatment system and supplies water to the home reticulation system. This means that every tap you open in your home or garden will trigger the pressure pump to come on and supply water at a good pressure.

The municipal supply is kept as a back up but isolated with a valve. The day that your borehole system has a problem or there is no power, your water supply can easily be restored by means of opening the municipal supply valve again.

Solar vs. Conventional Electrical

There are pros and cons of each system which we will explain to you at the time of selecting which way to go. The initial cost of a solar pumping system is higher than a conventional electrical system. One option that we do offer, is to install a pump that allows you to utilize both Solar & conventional power. This is proprietary information which, for obvious reasons we do not wish to share publicly on this forum, but will be willing to explain it all to you at the time of pump selection. Suffice it to say, we are continually on the lookout of ways to improve, work through and around obstacles (Eskom) to provide you with the best off the grid solution for your home.