Quick answer: Make borehole or tank water safe in this order: test it, filter out sediment first, add a carbon filter for taste and odour, then finish with a UV steriliser to kill bacteria and viruses. UV only works on clear water, so it never replaces the sediment stage. Compare lab results with SANS 241, which requires no E. coli in 100 mL, and retest at least once a year.
Is my borehole water safe to drink?
You cannot tell by looking or tasting. Clear, cold borehole water can still carry bacteria, high nitrates or fluoride. Water that looks cloudy or rusty may be perfectly safe to drink once it settles, but it needs a closer look.
The only reliable answer is a laboratory test. Ask an accredited water lab for a microbiological test (E. coli and total coliforms) and a chemical test (nitrate, fluoride, iron, manganese, pH and total dissolved solids). Take the sample the way the lab tells you, in their bottle, from a tap that has run for a few minutes.
What does SANS 241 say about drinking water?
SANS 241-1:2015 is the South African drinking water specification. It is written for water service providers, but most people use its limits as a yardstick for private supplies. These are the numbers worth knowing:
| Determinand | SANS 241-1:2015 limit | Why it matters |
|---|---|---|
| E. coli | Not detected per 100 mL | Acute health risk (faecal contamination) |
| Total coliforms | 10 or fewer per 100 mL | Operational indicator |
| Turbidity | 1 NTU or less (operational), 5 NTU or less (aesthetic) | Cloudiness also shields germs from UV |
| Nitrate as N | 11 mg/L or less | Acute health risk, especially for infants |
| Fluoride | 1.5 mg/L or less | Chronic health risk |
| Total dissolved solids | 1,200 mg/L or less | Taste and scaling |
| Iron | 300 ug/L aesthetic, 2,000 ug/L chronic | Staining and taste |
| Manganese | 100 ug/L aesthetic, 400 ug/L chronic | Staining and taste |
These figures come from the published standard text (see Sources). Check the current edition if you need them for compliance.
Which filter removes what?
Each stage does a different job, and they work best in a fixed order:
- Sediment filter (5 micron): removes sand, silt, rust flakes and dirt. It protects your pump, taps and every stage after it. JOJO’s own filter guide suggests changing sediment cartridges roughly every 3 to 6 months.
- Carbon filter: improves taste and smell. Carbon cartridges can last up to about 12 months depending on the water.
- UV steriliser: neutralises bacteria and viruses. It removes nothing physically and leaves no disinfectant behind in the pipes or tank.
Filters like these do not remove dissolved nitrate, fluoride or high salinity. Researchers at the University of Pretoria note that many rural borehole supplies exceed 1.5 mg/L fluoride, 6 mg/L nitrate-nitrogen or 1,500 mg/L salinity, and that ion exchange or reverse osmosis is needed to treat them. If your lab report shows a chemical problem, talk to a water treatment specialist before buying more cartridges.
How does UV treatment work, and what are its limits?
A UV unit passes water past a lamp that damages the genetic material of germs so they cannot multiply. The dose depends on lamp strength and how long the water is in the chamber. The UK Drinking Water Inspectorate gives about 40 mJ/cm2 as a typical minimum dose and says the water should be pre-filtered to well under 1 NTU where tougher organisms such as Cryptosporidium are a concern.
Four practical rules follow from that guidance:
- Filter first. Cloudy or iron-rich water blocks UV and lets germs hide behind particles.
- Stay within the rated flow. Do not push more water through than the unit is designed for.
- Replace the lamp every 10 to 12 months. A tired lamp still glows, but its output drops to around 70% of new, so the light does not prove the dose is enough.
- Clean the quartz sleeve. Scale on the sleeve cuts the UV that reaches the water.
Because UV leaves no residual protection, keep storage tanks closed, covered and clean after the UV unit.
Worked example: a Limpopo farm with a borehole
A farmhouse and two worker cottages (about 10 people) pump borehole water to a tank. The lab report shows no E. coli but a few coliforms, some sand and an iron level above the aesthetic limit. Nitrate and fluoride are within SANS 241.
- Peak demand: about 10 people at 200 litres each per day is 2,000 L a day. Peak flow at the taps might reach 1,000 L/h, which is well inside the 2,720 L/h rating of a 55 W in-line UV unit.
- Stages: a 5 micron sediment cartridge to catch sand, a carbon block for iron taste and smell, then UV.
- Check: retest after installation, and again every year or after any flood or pump repair.
That system needs no chemicals and runs on a small amount of electricity. You are not treating the whole farm, only the drinking and kitchen supply, so you can keep irrigation and stock water on the raw line and save cartridges.
How much does borehole water treatment cost?
Prices below are Kamano prices, VAT included. Browse the full water filters range.
For the farm above, the filter set (R2,079) plus an in-line UV unit (R2,000) comes to R4,079. Yearly running costs are modest: four sediment cartridges at R203 is R812, one carbon block at R198 and one UV lamp at R440, about R1,450 a year. If you prefer a ready-made package, look at our tank and pump combo kits, some of which include UV and filters. The 800 L tank combo with 0.75 kW pump, UV light and filters is R10,640. Cartridge life will be shorter in sandy water.
If you are still choosing a pump, our guide on how to choose a borehole pump covers depth, yield and head. Pumps are listed in the borehole pumps category.
Delivery is by Kamano’s own trucks to all 9 provinces in 1 to 3 business days. Fees by order weight, VAT included, are R550 up to 30 kg, R950 up to 60 kg and R1,450 up to 100 kg, and over 100 kg is quoted. Orders of R20,000 or more get free delivery with coupon code KH027, which does not work below R20,000. See our Polokwane delivery page. Payment is by EFT, and trade buyers can request a quote at our quote page.
How often should I retest and maintain the system?
Test at least once a year, and again after floods, a pump pull, a new tank or any change in taste, smell or colour. Keep a simple log of cartridge changes and lamp dates on the wall next to the filter frame.
Sanitise the tank and pipes if a test ever shows E. coli, then retest. A UV unit is a barrier, not a repair for a contaminated tank.
Buying from outside South Africa?
Kamano’s standard delivery covers South Africa only. Buyers in Botswana, Zimbabwe, Namibia and Mozambique should contact Kamano before ordering to discuss cross-border options. Call or WhatsApp +27 73 679 0837 or email sales@kamanoindustrial.co.za.
Sources
- SANS 241:2015 Parts 1 and 2, drinking water quality (published text)
- UV disinfection, UK Drinking Water Inspectorate
- Water defluoridation, denitrification and desalination in rural South Africa (University of Pretoria)
- What water filtration device do you need and why? (JOJO)
Frequently asked questions
What is the best way to purify borehole water for drinking?
Test first, then filter and disinfect in order: a 5 micron sediment filter, a carbon filter, then a UV steriliser. UV needs clear water to work. If the lab shows high nitrate or fluoride, filters will not fix it and you need ion exchange or reverse osmosis.
Does UV remove bacteria from water?
UV neutralises bacteria and viruses so they cannot multiply, but only when the water is clear and the unit runs within its rated flow. It does not remove particles, chemicals or salts, and it leaves no protection in the pipes. Replace the lamp roughly every 10 to 12 months.
What does SANS 241 say about E. coli in water?
SANS 241-1:2015 says E. coli must not be detected in a 100 mL sample, and it treats this as an acute health risk. Total coliforms should be 10 or fewer per 100 mL. If E. coli shows up, disinfect the tank and plumbing, then retest.
How often should I test borehole water?
Test at least once a year, and again after floods, pump repairs, a new tank or any change in taste, smell or colour. Use an accredited laboratory, test for microbes and key chemicals such as nitrate and fluoride, and keep the results to track trends.