Water Testing Laboratory
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What is a coliform?

A coliform is defined as aerobic and facultative anaerobic, gram negative, non-sporulating bacilli that produce acid and gas from the fermentation of lactose.

Total coliforms are the primary measure of microbial quality in drinking water, are usually non-pathogenic, and are found in human and animal waste, soil run-off, and vegetation.

Total coliforms are indicative of recent fecal pollution, effectiveness of treatment, deterioration of water quality in a distribution system, and progress in remediation.

Fecal coliforms are the subset of total coliforms that are commonly found in the feces of humans and animals.

Escherichia coli is a specific species of fecal coliform that is very pathogenic.