Borehole Drilling in Free State

Geology and what to expect

Bloemfontein sits on Karoo sandstone and mudstone with dolerite sills and dykes. The British Geological Survey describes Karoo rocks as low in permeability, with groundwater moving mainly through fractures, limited storage and typical borehole yields of 1 to 3 L/s. Boreholes sited on fractured zones or contacts around dolerite can do better, but results are very variable and a dry borehole is possible. We have not sourced the geology of the rest of the province.

These are regional pictures. Depths and yields vary widely within a suburb, only a site survey and the driller's log can tell you what your plot will give, and a borehole can be dry.

Borehole drilling prices in Free State

One online price guide gives R290 to R520 per metre and R40,000 to R95,000 for a typical project, with typical depths of 40 to 110 m.

The price guide lists Bloemfontein only.

Prices come from published price guides, not from quotes. The main guide does not say whether its per-metre rates include casing, VAT or mobilisation, and a fully equipped system (pump, tank and installation) costs more than a drilled and cased hole. Ask for written quotes that say what is included.

National pricing guide · Cost calculator

Water quality and SANS 241 priorities

The British Geological Survey says most Karoo groundwater has total dissolved solids of 450 to 1,000 mg/L, highest in the west and south of the basin, and often of sodium-chloride type. Test total dissolved solids, sodium and chloride, plus E. coli and nitrate.

• E. coli: not detected in 100 mL (acute health)
• Nitrate: 11 mg/L as N or less (acute health)
• Total dissolved solids: 1,200 mg/L or less (aesthetic)
• Sodium: 200 mg/L or less (aesthetic)
• Chloride: 300 mg/L or less (aesthetic)

Whatever the province, the baseline checks are E. coli, nitrate, pH and total dissolved solids. Only a lab test tells you what your water holds.

Water quality guide · Is borehole water safe to drink?