Well water testing in the Okanagan

There's no free provincial program: use a qualified lab (search the CALA directory), which supplies the bottles. HealthLinkBC recommends testing for bacteria at least once a year and for chemistry when the well is new and annually after that.

• Bacteria (total coliforms and E. coli): at least once a year, and right away if the water's clarity, colour or taste changes.
• Chemistry when the well is new and every year after: HealthLinkBC names nitrates, fluoride and metals such as arsenic, lead, copper and manganese as the most common concerns in B.C. groundwater.

Search the CALA directory for an accredited lab near you; the lab supplies sterile bottles and instructions, and charges for the analysis. Read the instructions carefully and follow them exactly, and keep every result for future reference.

Interior Health says private systems have minimal regulatory oversight and that the homeowner is responsible for making sure the water is safe for drinking, cooking and household sanitation; for a rental, it becomes a legal requirement for the landlord. It says surface water and well water should be tested, that surface water and many groundwater sources should be disinfected, and it links to the Provincial Health Services Authority's list of labs approved for drinking water microbiology testing. If your water comes from the lake or a stream, watch for algae blooms: Interior Health says boiling will not remove algal toxins, and to use another source for drinking, and for pets and livestock, during a bloom.

HealthLinkBC says water with E. coli is not safe to drink: treat it before drinking, preparing food or brushing teeth (boiling is a short-term option), then find and fix the source, with long-term treatment if the source can't be corrected. Total coliforms without E. coli can mean the well needs better sanitation or physical upgrades, or that surface water may be getting in. Re-test after floods, drought or similar events, and don't rely on a neighbour's result: a safe test next door doesn't mean your water is safe.

Before disinfecting, the province's guide to simple chlorination asks you to check the wellhead:

• Sewage sources near the well, such as manure or compost piles or a septic field.
• Ground that slopes toward the well or lets water pond around it.
• A missing, cracked or damaged well cap, or one that lets water or vermin in.
• Casing that sticks up less than 30 cm (1 ft) above the ground or pump-house floor, or a gap or cracks in the seal around it.

Fix those first, or the well stays vulnerable. A registered well driller or pump installer has to do any surface-seal repair or casing extension, and the guide warns that chlorine vapour is dangerous in confined spaces such as pump houses, well pits and crawl spaces.

Read more: The well water guide.