How do you shock a well after a positive coliform test?

Find the entry point first, then shock, then retest. Coliform in a well means something is getting in, so walk the wellhead for the usual doorways: a loose or cracked cap, a casing that does not stand clear of ponding water, ground sloping toward the well. Seal the doorway, run a full shock treatment through the well and plumbing, flush, and retest one to two weeks later. Drink from another source until the retest comes back clean.

Shocking without fixing the entry point is a treadmill: the treatment clears the water and the doorway lets the next dose of bacteria in. The cap gasket is the cheapest fix in well ownership and the most common answer.

The dose is sized by your well's gallons, from its depth, casing diameter, and static water level. We pull those numbers from your state's official well record and pack the kit to them, with the residual test that proves the treatment held.

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We pull your well's dimensions from your state's official record and pack a chlorine dioxide kit to them, from $399.

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