Borehole water can look clear and still be unsafe to drink. The only way to know is a laboratory test. Here's what's involved.
When to test
- Before you first drink it from a new borehole
- Once a year after that, or more often if you have small children at home
- After anything changes: heavy flooding, a change in taste, colour or smell, or work near the borehole
What a lab test usually checks
- Microbiological: bacteria such as E. coli and total coliforms, which point to contamination from sewage or animals
- Chemical: things like nitrates, iron, manganese, fluoride and hardness
- Physical: pH, turbidity (cloudiness), colour and conductivity (dissolved salts)
Results are compared with the South African drinking water standard, SANS 241. Ask the lab to show your results against it.
How to take a sample
Use the sterile bottle the lab supplies and follow their instructions exactly. Samples for bacteria usually need to reach the lab within a day and be kept cool. Many borehole companies can arrange the sampling for you.
Common problems and fixes
- Orange or brown staining: usually iron or manganese, treated with specific filters
- Hard water (scale on kettles): softening or conditioning
- Bacteria: disinfection such as UV treatment, plus finding and fixing the source
Choose filtration after the test, not before. Otherwise you may pay for equipment that doesn't fix your actual problem.
This guide is general information. Follow the lab's advice on whether your water is safe to drink.