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National Drinking Water Database


National Drinking Water Database - Chemical Contaminants

The Most Polluted Communities

11,205 water utilities reported detecting Bromoform in tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies

Ranked by population

RankSystem Population Served Positive test results of total reported tests Average Level
(Range)
1Metropolitan Water District of Southern California
Los Angeles, CA
17,000,0002 of 21.5 ppb
(1.5 ppb)
2Los Angeles Department of Water and Power
Los Angeles, CA
3,828,700236 of 3032.19 ppb
(0 to 14.7 ppb)
3Chicago Department of Water Management
Chicago, IL
2,896,0162 of 280.06 ppb
(0 to 1.2 ppb)
4City of Houston Public Works
Houston, TX
2,700,00028 of 510.34 ppb
(0 to 2.4 ppb)
5Miami-Dade Water & Sewer Department
Miami, FL
2,100,00012 of 120.21 ppb
(0.2 to 0.33 ppb)
6Washington Suburban Sanitary Commission
Silver Spring, MD
1,800,00097 of 1020.11 ppb
(0 to 0.44 ppb)
7Baltimore City Department of Public Works
Baltimore, MD
1,600,00025 of 1090.16 ppb
(0 to 2 ppb)
8Cleveland Division of Water
Cleveland, OH
1,500,00012 of 600.1 ppb
(0 to 0.9 ppb)
9San Diego Water Department
San Diego, CA
1,281,40066 of 664.78 ppb
(1.38 to 12.26 ppb)
10San Antonio Water System
San Antonio, TX
1,219,11330 of 351.67 ppb
(0 to 7.3 ppb)
11Dallas Water Utilities
Sunnyvale, TX
1,188,5802 of 16< 0.01 ppb
(0 to 0.09 ppb)
12Suffolk County Water Authority
Bay Shore, NY
1,009,26431 of 740.51 ppb
(0 to 5.2 ppb)
13San Jose Water Company
San Jose, CA
979,00012 of 2740.09 ppb
(0 to 9.85 ppb)
14City of Columbus Department of Public Utilities
Columbus, OH
897,21311 of 130.68 ppb
(0 to 1.3 ppb)
15Fairfax Water
Merrifield, VA
823,2161 of 30.17 ppb
(0 to 0.5 ppb)
16Indianapolis Water
Indianapolis, IN
805,43117 of 740.08 ppb
(0 to 1.27 ppb)
17Greater Cincinnati Water Works
Cincinnati, OH
775,0001 of 17.51 ppb
(7.51 ppb)
18United Water New Jersey
Haworth, NJ
773,4588 of 280.09 ppb
(0 to 0.85 ppb)
19Tucson Water
Tucson, AZ
675,0007 of 73.73 ppb
(2.83 to 4.24 ppb)
20Austin Water Utility
Austin, TX
669,6939 of 150.91 ppb
(0 to 2.37 ppb)