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Testing for bacteria

Bacteria testing looks for total coliform and E. coli — indicator organisms that show whether surface contamination can reach the water. It's the basic annual check for every private well.

When it's called for

How it works

An accredited lab (or a state/county health program, often cheaper) provides a sterile bottle and strict collection instructions. Results report presence or absence of total coliform and E. coli — presence/absence is the answer, not a level.

A positive result calls for your county or state health guidance first — retesting, well inspection and disinfection of the cause. Equipment like UV is a barrier after that, never instead of it.