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WaterSafety

Total Coliform in Drinking Water

Microbial · MCL: 5 % positive · 0 systems exceeding limit

Overview

Total Coliform is regulated under the Safe Drinking Water Act with an MCL of 5 % positive. The EPA Safe Drinking Water program sets and enforces the maximum contaminant levels shown here.

Health Effects

Exposure to Total Coliform above the MCL of 5 % positive may cause adverse health effects. Consult EPA fact sheets for detailed information.

Sources of Contamination

Total Coliform can enter drinking water from natural deposits, industrial discharges, or other sources.

Treatment & Removal

Treatment methods for Total Coliform include activated carbon filtration, reverse osmosis, and specialized media.

How to Remove Total Coliform From Water

These filtration methods are effective for reducing Total Coliform in drinking water:

Filter MethodEffectivenessCost RangeCertification
UV Disinfection99.99% inactivation$150-500 (point-of-use)NSF/ANSI 55 (Class A)
Reverse Osmosis (RO)99%+ removal$200-500 (under-sink)NSF/ANSI 58
Ceramic Filters99.99% removal$30-150NSF P231
UV Disinfection — details

Best method for microbial treatment. No chemicals added.

Reverse Osmosis (RO) — details

Effectively removes coliform bacteria through physical filtration.

Ceramic Filters — details

Absolute pore size blocks bacteria. Long-lasting and low maintenance.

Water Systems with Total Coliform Detected

San Antonio Water System

San Antonio, Texas

2,113,151 people
B

Gru - Murphree Wtp

Gainesville, Florida

195,681 people
C

Clermont Public Water System

Batavia, Ohio

133,059 people2 violations
F

Chicago

Chicago, Illinois

2,746,388 people
C

Cicero

Cicero, Illinois

83,000 people1 violation
C

Detroit City Of

Detroit, Michigan

633,218 people
A

Atlanta

Atlanta, Georgia

1,089,893 people5 violations
F

Dekalb County

Decatur, Georgia

743,000 people
A

North Fulton County

Alpharetta, Georgia

434,517 people
B

Durham, City Of

Durham, North Carolina

322,083 people
C

Newark Water Department

Newark, New Jersey

294,274 people22 violations
F

Nj American Water - Western

Delran, New Jersey

264,586 people
C

Jersey City Mua

Hoboken, New Jersey

262,000 people1 violation
C

Wildwood City Water Department

Rio Grande, New Jersey

218,472 people
C

Everett Public Works Dept. City Of

Everett, Washington

215,774 people
A

Kent Water Department

Kent, Washington

166,421 people
A

Cambridge Water Department

Cambridge, Massachusetts

118,214 people
A

Warren County Water District

Bowling Green, Kentucky

91,118 people
B

Hardin County Water District #2

Elizabethtown, Kentucky

76,326 people
C

Salem Public Works

Salem, Oregon

199,820 people
B

Medford Water Commission

Medford, Oregon

106,068 people
B

Berkeley County Pswd-Potomac River

Martinsburg, West Virginia

34,786 people
C

Albuquerque Water System

Albuquerque, New Mexico

560,326 people
A

Rio Rancho Water & Ww Services

Rio Rancho, New Mexico

107,350 people
B

Wichita, City Of

Wichita, Kansas

395,699 people
A

West Jordan City Water System

West Jordan, Utah

117,025 people
B

St George City Water System

St George City, Utah

105,240 people
C

Aquarion-Eastern Fairfield County

Shelton, Connecticut

351,756 people
C

Aquarion-Stamford

Shelton, Connecticut

119,214 people
B

Waterbury Water Department

Waterbury, Connecticut

107,271 people
C

Howard County D.p.w. Distribution

Columbia, Maryland

286,158 people
B