E. coli in Drinking Water
Microbial · MCL: 0 presence · 0 systems exceeding limit
Overview
E. coli is regulated under the Safe Drinking Water Act with an MCL of 0 presence. The EPA Safe Drinking Water program sets and enforces the maximum contaminant levels shown here.
Health Effects
Exposure to E. coli above the MCL of 0 presence may cause adverse health effects. Consult EPA fact sheets for detailed information.
Sources of Contamination
E. coli can enter drinking water from natural deposits, industrial discharges, or other sources.
Treatment & Removal
Treatment methods for E. coli include activated carbon filtration, reverse osmosis, and specialized media.
How to Remove E. coli From Water
These filtration methods are effective for reducing E. coli in drinking water:
| Filter Method | Effectiveness | Cost Range | Certification |
|---|---|---|---|
| UV Disinfection | 99.99% inactivation | $150-500 (point-of-use) | NSF/ANSI 55 (Class A) |
| Reverse Osmosis (RO) | 99%+ removal | $200-500 (under-sink) | NSF/ANSI 58 |
| Ceramic Filters | 99.99% removal | $30-150 | NSF/ANSI 53 P231 |
UV Disinfection — details
Most effective for bacteria. Must be Class A rated for microbiological purification.
Reverse Osmosis (RO) — details
Physical barrier removes bacteria. Must be maintained to prevent biofilm.
Ceramic Filters — details
Pore size of 0.2 microns or smaller blocks bacteria. Gravity-fed options available.
Water Systems with E. coli Detected
San Antonio Water System
San Antonio, Texas
Jea Major Grid
Jacksonville, Florida
Emerald Coast Utilities Authority (ecua)
Pensacola, Florida
Tallahassee, City Of
Tallahassee, Florida
Aqua Pa Main System
Bryn Mawr, Pennsylvania
Chicago
Chicago, Illinois
Cicero
Cicero, Illinois
Nj American Water - Western
Delran, New Jersey
Jersey City Mua
Hoboken, New Jersey
Wildwood City Water Department
Rio Grande, New Jersey
Mesa City Of
Mesa, Arizona
Springfield Water and Sewer Commission
Springfield, Massachusetts
Madison Water Utility
Madison, Wisconsin
City of Olive Branch
Olive Branch, Mississippi
Berkeley County Pswd-Potomac River
Martinsburg, West Virginia
Roswell Municipal Water System
Roswell, New Mexico
Olathe, City Of
Olathe, Kansas
Salt Lake City Water System
Salt Lake City, Utah
St George City Water System
St George City, Utah
Waterbury Water Department
Waterbury, Connecticut
City of Baltimore
Baltimore, Maryland