Ontario · Home health · checked September 28, 2026

Well water testing in Ajax

Ajax is a largely built-up town on Durham Region water, so private wells are rare. If yours is, here's how testing works in Ontario.

Ask a question → The well water guide
Filling a water-sample bottle at a farmhouse kitchen tap with the aerator removed, snowy fields and a barn outside

Private wells in Ajax

Rare

Testing cost

Bacteria free (Public Health Ontario)

Test for

Bacteria yearly or more

Extended panels

Nitrate, metals, more

How Ajax is built

Ajax's houses by when they were built Ten house shapes, one for each tenth of Ajax's 35,260 houses. Before 1961: 6%, 1961–1990: 36%, 1991–2000: 15%, 2001 or later: 44%. Older houses glow hotter.
  • Before 1961 6%
  • 1961–1990 36%
  • 1991–2000 15%
  • 2001 or later 44%
Each house stands for one in ten of Ajax's 35,260 houses (single-detached, semi-detached, row and duplex), drawn by when it was built. The glow shows the usual pattern: older houses tend to be leakier and less insulated. Snowfall scales with heating degree-days. Sources: Statistics Canada 2021 Census (table 98-10-0233-01), NRCan HOT2000 climate data.

Wells in Ajax

Ajax is a largely built-up town on Durham Region water, so private wells are rare.

How testing works in Ontario

Free bacteria testing through Public Health Ontario labs: pick up a kit at a PHO lab or your public health unit and drop it back off. Chemistry (nitrate, sodium, metals) goes to a licensed private lab for a fee. Local health units recommend testing at least three times a year: spring, summer and fall.

What to test for

  • Bacteria (total coliforms and E. coli): at least once a year, and after flooding, heavy rain or work on the well.
  • Nitrate, especially near farmland or septic systems.
  • Metals and naturally occurring contaminants such as arsenic, uranium or manganese when a well is new and every few years after, depending on local geology.

Our well water guide.

Well water testing in Ajax: common questions

Is well water testing free in Ontario?

Free bacteria testing through Public Health Ontario labs: pick up a kit at a PHO lab or your public health unit and drop it back off. Chemistry (nitrate, sodium, metals) goes to a licensed private lab for a fee. Local health units recommend testing at least three times a year: spring, summer and fall.

How often should I test my well?

For bacteria, at least once a year and after flooding, heavy rain or well work; many health units recommend more often. Test chemistry when the well is new and every few years after.

Are private wells common in Ajax?

Ajax is a largely built-up town on Durham Region water, so private wells are rare.

Well water testing near Ajax

Well water testing in Pickering7 kmWell water testing in Whitby7 kmWell water testing in Oshawa15 kmWell water testing in Markham22 kmWell water testing in Clarington29 km All 70 cities →

Sources

Checked September 28, 2026. Census figures are for the municipality (Ontario); climate data is NRCan's HOT2000 station Toronto Buttonville (27 km away).

Ask about well water testing in Ajax

Tell us your postal code and what you’re dealing with. We’ll reply with the right kind of certified professional or lab for your area, and which programs apply.

Email us what you’re planning, your postal code and the type of building (a house, a duplex or triplex, or a larger multi-unit building) — we’ll reply with registered service organizations for your area and which rebates apply.

Email dave@clickshift.ca

This inbox is answered by a person. Participating advisors pay us a referral fee — you pay nothing, and it never affects the directory.