Coliform testing is an indicator check for possible pathways that can allow germs into a private well. E. coli adds a more specific signal of fecal contamination, but neither result should be interpreted without the laboratory and local health department.
Reviewed 2026-09-05Rural Home Compass editorial deskData record microbial-indicators
The analyte, certified method, sample location, container, handling, and date are part of the result—not just the number on the report.Laboratory analyses in this record
total coliform bacteria
E. coli
Why this appears in a test plan
Use this record to establish a recurring baseline and to decide when an event such as flooding or well work justifies faster testing.
baseline: CDC includes total coliform bacteria in the recurring baseline for private wells.
flood or repair: Flooding, well work, and land disturbance can create a new pathway for microbial contamination.
illness: Possible water-related illness needs prompt public-health guidance and certified laboratory testing.
new property: A current microbial result replaces an unknown seller or prior-owner baseline.
What the result can tell you
Whether total coliform bacteria were detected in the submitted sample.
Whether E. coli was detected when that analysis is included by the certified laboratory.
What it cannot prove
That every possible disease-causing organism is absent from the water.
Where contamination entered the well or whether one sample represents future water quality.
Use the result safely
Use the laboratory container and sampling instructions exactly; microbial samples have handling and timing requirements.
Discuss any positive result with the laboratory and local health department before returning the water to normal drinking use.
This page and the recommender read from the same structured record. Sources were checked on 2026-09-05; local instructions override this national explanation.
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