Contaminant guide

Total coliform / E. coli

Coliform bacteria are indicators. Their presence can signal a pathway for disease-causing microbes. E. coli in drinking water is an acute health concern.

Health context

E. coli indicates fecal contamination and can cause serious gastrointestinal illness.

EPA standard notes

Under the Revised Total Coliform Rule, E. coli has an MCL goal of zero; assessments and corrective action are required when triggered.

Standards and rules change—confirm on epa.gov/sdwa.

What you can do

FAQ

Is a filter required?

Not automatically. Many systems meet standards without point-of-use filters. Filters can be useful for taste, specific contaminants, or home plumbing issues—match certifications to the problem.

Where should I verify numbers?

Your utility’s Consumer Confidence Report, public notices, TCEQ resources, and EPA ECHO/SDWIS records.