Irene sits on dolomite south of Pretoria, with smallholdings, estates and the historic village all drawing on the same karst ground.
Good yields are achievable, and the ground stability requirements apply across all of it.
What Is Under Irene
The formations below are what a rig actually meets on a Irene property, and between them they govern the depth, the casing requirement and what the hole will realistically give you.
| Formation | Where it sits | What it means for drilling |
|---|---|---|
| Malmani Subgroup dolomite | The karst bedrock underlying much of Centurion and its surrounds | A high-yielding aquifer where cavities and solution channels are intersected, and the single most safety-sensitive formation to drill in the country. |
| Chert residuum and wad | The weathered blanket over the dolomite | Low-density, highly compressible material. Uncontrolled water movement through it is the mechanism behind sinkhole formation. |
| Syenite and diabase intrusions | Cutting the dolomite and forming compartment boundaries | They divide the aquifer into hydraulically separate compartments, which is why yields differ so sharply across short distances. |
Send your street and what the water is for, and get an itemised quote for Irene.
Get a Irene Borehole QuoteWhat That Means for Your Borehole
- This ground carries genuine sinkhole risk, and drilling protocol on it is not a formality. Uncontrolled water loss into the subsurface is what triggers subsidence.
- Yields can be very high where cavities are intersected, and disappointing a street away, because compartments are hydraulically separate.
- Site stability assessment comes before drilling, not after. On dolomite that is the order of operations, full stop.
Where We Work Around Irene
- Irene village and the historic side
- Southdowns and the estate developments
- Doringkloof and Cornwall Hill boundaries
- Smallholdings on the Irene farm side
- Nellmapius road properties
- Centurion approaches
What to Watch For Here
Smallholding abstraction takes you past Schedule 1, which needs settling under the National Water Act before drilling.
Estate and heritage conditions apply in parts of Irene, alongside rather than instead of the municipal and dolomite requirements.
What the Water Is Used For
- Stock watering and animal supply
- Orchard, vegetable and pasture irrigation
- Stable, shed and equipment washdown
- Household supply where the analysis allows it
- Fire water and standby storage
Wellpoint or Borehole?
No. Dolomite karst is the wrong setting for a driven point entirely, and attempting shallow abstraction on this ground raises the stability questions rather than avoiding them.
Water Quality in Irene
Dolomitic groundwater is typically hard - high in calcium and magnesium - which scales kettles, geysers and irrigation fittings over time. It is otherwise generally good quality. Softening is straightforward once an analysis quantifies the hardness.
A water analysis is what turns that from a general expectation into a number for your specific hole, and treatment should be specified against the result rather than against the area's reputation.
Registration and Abstraction
Boreholes in the City of Tshwane are subject to municipal registration, and on dolomitic ground the City applies additional geotechnical requirements because of sinkhole risk. Cross-connection to the municipal supply is prohibited. The National Water Act governs abstraction on top of that: domestic use generally falls under Schedule 1, larger volumes may require registration or authorisation from the Department of Water and Sanitation. This is the one setting where the regulatory step is not paperwork - it is the safety case for the hole. Requirements change, so confirm your position before drilling.
Related Services
For the drilling process itself, the geology across the rest of the country and how a quote is put together, see Borehole Installers South Africa.
Borehole Prices in Irene
Drilling is charged per metre, so depth drives the total. The ranges below are framed for local ground conditions and access.
| Item | Indicative range | What moves it locally |
|---|---|---|
| Drilling, per metre | R500 - R1,100 /m | Dolomite drills reasonably but cavity intersections complicate the hole and the protocol adds cost. |
| uPVC casing, installed, per metre | R450 - R850 /m | Casing and sealing through the residuum is a stability requirement here, not just a hole-stability one. |
| Mobilisation and site establishment | R3,500 - R12,000 | Access and site conditions move this; a site visit settles it before quoting. |
| Water survey | R5,000 - R12,000 | Targets structure rather than depth. Worth most where yield is fracture-dependent. |
| Yield testing | R3,500 - R15,000 | Establishes the sustainable rate that pump selection depends on. |
| Pump, supplied and installed | R15,000 - R45,000 | Greater depth means more head, which means a larger pump and heavier cable. |
| Storage and booster | R12,000 - R35,000 | Needed wherever peak demand exceeds the borehole's sustainable rate. |
| Typical complete project | R90,000 - R240,000+ | Everything above, excluding treatment, which depends entirely on the water analysis. |
These are indicative ranges, not a quotation. They are compiled from published South African supplier and contractor pricing to give you a starting point for budgeting. They are not our rate card, and no figure here is a commitment.
Treat them as a broad guide only. Published borehole pricing in South Africa varies enormously - different 2026 guides quote per-metre drilling rates for the same province that differ by a factor of three - because depth, geology, access, specification, distance and fuel costs all move the number. Depth in particular is not known until the hole is finished. Figures generally exclude VAT unless noted, and change over time. Only an itemised written quote against your actual site means anything.
Irene Borehole FAQs
Can an Irene smallholding rely on a borehole?
Often yes, because dolomitic ground can be genuinely productive where a hole intersects solution cavities.
It is inconsistent between compartments, though, so the yield test matters more than a neighbour's experience. And on this ground the stability assessment comes first regardless.
Is the dolomite risk the same across Irene?
It varies with the thickness and nature of the residuum over the dolomite, which differs across the area. That is precisely what a site stability assessment establishes.
The presence of dolomite does not rule out drilling. Doing it without assessing the ground first is what creates the problem.
Is it safe to drill a borehole in Irene?
It can be done properly, but dolomitic ground carries real sinkhole risk and it is the one setting where the geotechnical question comes before the water question.
That means a site stability assessment first, a contractor who works to dolomite protocol, correct casing and sealing through the residuum, and no uncontrolled water loss into the subsurface. A contractor who shrugs at this on Centurion ground is the wrong contractor.
Why do yields vary so much between neighbouring Irene properties?
Because dykes and intrusions divide the dolomite into separate compartments that do not share water. One compartment can be highly productive while the adjacent one is not.
It also means a neighbour's excellent borehole tells you less about your own prospects here than it would almost anywhere else.
NEED A BOREHOLE IN IRENE?
Send your street and what you need the water for, and get an itemised quote.
Get My Free QuoteGet a Borehole Quote in Irene
Tell us where you are and what the water is for.
Client Reviews
Powered by leaderr
