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CONTAMINANT

Chloroform

FOUND

Exceeding guidelines

STATES DETECTED

46

serves

252 million

utilities detected

24,872

states detected

46

serves

234 million

utilities detected

20,760

Overview

Chloroform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Chloroform and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. learn more about this contaminant

In addition to tap water disinfection, chloroform pollution in the environment also comes from industrial discharges from pulp and paper mills, and from urban wastewater effluent. Human studies show that chloroform damages the kidneys, liver and central nervous system. In animals, chloroform causes infertility, birth defects and cancer.

Click here to read more about disinfection byproducts.

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 0.4 ppb

The EWG Health Guideline of 0.4 ppb for chloroform was based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.

ppb = parts per billion

National Standard Exists

Health Concerns:

  • Cancer

  • Harm to fetal growth and development

Want to remove
Chloroform from your water?

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Activated Carbon, 

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Chloroform around the Country

UTILITIES REPORTING ABOVE HEALTH GUIDELINES UTILITIES WITH CONTAMINATION
State Utilities People Served Utilities People Served
California1,01730,360,2901,23134,977,868
Texas2,19725,756,0482,82428,253,911
New York1,23917,473,2211,47118,865,351
Illinois1,51211,782,2731,56511,866,048
Pennsylvania1,18010,990,1881,35911,184,495
Ohio92010,289,7891,09310,496,689
Georgia6179,278,5629469,844,031
North Carolina9179,230,9139649,309,764
New Jersey4148,354,8364848,808,590
Washington6256,965,8718688,144,938
Virginia6497,168,0677467,239,048
Tennessee3326,994,0183527,140,825
Massachusetts2916,176,5423786,609,147
Florida2266,389,5542476,470,415
Colorado6136,183,0707156,288,121
Louisiana7774,811,2388845,077,106
Missouri5934,471,4468124,969,097
Alabama2114,097,9862714,562,837
Maryland1614,360,1331994,473,862
Minnesota5614,108,7506354,348,680
South Carolina3303,788,6063603,897,979
Wisconsin4663,483,1665713,880,646
Oklahoma5763,366,0326273,458,819
Utah1822,752,8742573,255,760
Nevada362,847,891712,944,088
Arkansas4962,584,0745562,787,042
Indiana2372,733,8632492,774,821
Iowa7202,500,3828222,722,662
Connecticut1922,644,3472412,678,327
Kansas5951,758,8587071,908,468
New Mexico1261,244,1122391,656,296
West Virginia3631,487,7343861,541,418
Arizona57467,0511051,474,138
Nebraska761,160,8271281,298,679
Rhode Island41997,35753999,650
Delaware119846,078143865,909
North Dakota259675,393276699,912
District Of Columbia4667,3254667,325
Idaho27400,12534581,035
Montana193466,934245564,823
Alaska153459,396169468,920
Vermont194417,944253460,352
Wyoming142433,654190456,293
Maine54267,83054267,830
Hawaii25206,67232240,858
Mississippi45131,99056150,170

Utilities with the highest amounts of chloroform, 2021-2023

ALL UTILITIES
LARGE UTILITIES
Utility Location Tests Average level People served
Lowndes County-alapaha Plantation S/dValdosta, GA24 of 24179.3 ppb296
Wanette Public Works AuthorityWanette, OK12 of 12167.2 ppb402
Asher Utility Dev AuthorityAsher, OK12 of 12158.9 ppb375
Cleveland Municipal AuthorityCleveland, OK24 of 24158.0 ppb3,262
City of Rose CityVidor, TX24 of 24157.2 ppb467
Boswell Public Works AuthorityBoswell, OK24 of 24142.0 ppb932
Lakewood Water SystemHuntington, TX15 of 15135.5 ppb42
Osage County Rural Water District # 20 (hulah)Bartlesville, OK13 of 13131.7 ppb350
MaysvilleMaysville, OK23 of 23129.9 ppb1,212
Madera Co. Md1-hidden Lake EstatesMadera, CA11 of 11128.4 ppb162
Grayhorse Rural Water DistrictFairfax, OK11 of 11127.3 ppb100
Echols County Water AuthorityStatenville, GA8 of 8117.6 ppb972
Chalkyitsik Village WaterChalkyitsik, AK8 of 8115.9 ppb75
City of NomeNome, TX26 of 27113.6 ppb837
Stringtown Public Works Authority*Stringtown, OK24 of 24111.3 ppb1,105
PittsburgPittsburg, OK13 of 13111.0 ppb280
Fcsa #30/el PorvenirFresno, CA11 of 11110.0 ppb241
Latimer County Rural Water District #3Wister, OK11 of 11109.5 ppb175
Westhaven Community Services DistrictTrinidad, CA11 of 11108.9 ppb490
Pushmataha County Rural Water District #3Antlers, OK24 of 24107.6 ppb4,825
Bellwood Water SystemProvencal, LA24 of 24107.6 ppb1,032
Brookmont AreaPulaski, VA12 of 12106.3 ppb100
Orient Water CompanyRepublic, WA12 of 12105.5 ppb167
FloridaAmsterdam, NY1 of 1105.0 ppb432
Mount ErieMount Erie, IL2 of 299.0 ppb116
Town of Tullos Water SystemTullos, LA24 of 2496.1 ppb792
Choctaw County Rural Water System & Solid Waste Management District #6*Boswell, OK26 of 2694.1 ppb850
Vixen Water SystemChatham, LA24 of 2492.9 ppb774
Anthony Harbor SubdivisionHuntington, TX15 of 1591.6 ppb101
Pineridge SubdivisionSavannah, GA24 of 2491.0 ppb105
Atoka County Rural Water District #1 (wardville)Kiowa, OK12 of 1290.8 ppb125
Fairview Union Water System*Coushatta, LA24 of 2489.4 ppb2,346
Miami Water Users AssociationSpringer, NM24 of 2489.3 ppb135
Dixon, Town OfDixon, WY13 of 1388.7 ppb97
Forest Water Supply CorporationWells, TX27 of 2788.7 ppb561
Fairfax*Fairfax, OK28 of 2888.3 ppb1,555
Sierra Country ClubCoupeville, WA4 of 588.0 ppb355
High Falls Water DistrictCottekill, NY5 of 587.8 ppb426
Rye, Town ofRye, CO14 of 1487.6 ppb745
Pushmataha County Rural Water District #2 (albion)Albion, OK26 of 2686.1 ppb959
Keota Public Works AuthorityKeota, OK23 of 2385.9 ppb564
Kotzebue Municipal Water SystemKotzebue, AK12 of 1285.8 ppb3,154
El Camino Bay Water SystemHemphill, TX14 of 1484.9 ppb280
Leflore County Rural Water District #3Whitesboro, OK26 of 2684.6 ppb1,643
Village of Sikes Water SystemSikes, LA24 of 2484.5 ppb639
Chester Water DepartmentChester, MA24 of 2484.2 ppb750
Galena Wtp1 - CityGalena, AK12 of 1282.8 ppb470
Pushmataha County Rural Water District #5 (nashoba)Nashoba, OK24 of 2482.7 ppb725
Madera Co. Sa16 Sumner Hill-water SystemMadera, CA12 of 1282.4 ppb135
Avant Utilities AuthorityAvant, OK13 of 1381.5 ppb361

* This water utility supplies finished drinking water to at least one other water utility. The purchasing utility is not required to test for or report Chloroform, but it likely has the contaminant in its water supply.

UtilityLocationTestsAverage levelPeople served
Plattsburgh CityPlattsburgh, NY13 of 1380.9 ppb24,908
Floyd Water District*Rome, NY12 of 1272.2 ppb34,560
East Longmeadow DPW Water DepartmentEast Longmeadow, MA48 of 4870.5 ppb16,162
Hamlet Water System*Hamlet, NC48 of 4870.3 ppb10,289
Amsterdam*Amsterdam, NY4 of 470.2 ppb22,132
Longmeadow Water DepartmentLongmeadow, MA40 of 4069.5 ppb15,701
Bridgeport City OfBridgeport, WV62 of 6265.1 ppb10,775
Springfield Water and Sewer Commission*Springfield, MA175 of 17560.0 ppb230,331
Lincoln Park Water Department*Lincoln Park, NJ52 of 5259.8 ppb11,000
City of Troy Public Utilities*Troy, NY42 of 4259.1 ppb117,581
Agawam Water DepartmentAgawam, MA48 of 4858.4 ppb28,849
Bethlehem Water District No. 1*Delmar, NY48 of 4857.8 ppb62,062
Galion CityGalion, OH48 of 4857.3 ppb10,453
Mohawk Correctional Facility*Rome, NY11 of 1157.2 ppb34,775
Somerset Water DepartmentSomerset, MA51 of 5156.9 ppb18,257
Bristol County Water Authority*Warren, RI96 of 9656.5 ppb49,000
Pvia*Wister, OK36 of 3656.5 ppb40,000
University of Central FloridaOrlando, FL4 of 456.3 ppb44,103
Watertown City*Watertown, NY144 of 14456.3 ppb29,406
Canandaigua-Farmington Consolidated WD*North Tonawanda, NY45 of 4556.2 ppb40,732
East Greenbush General WDEast Greenbush, NY71 of 7156.1 ppb10,200
Thomson-McDuffie County W&S Comm.Thomson, GA51 of 5156.0 ppb21,312
Warren City PWS*Warren, OH48 of 4854.8 ppb49,130
Baldwin County*Milledgeville, GA50 of 5054.2 ppb23,067
TUD - Sonora/Jamestown Water System*Sonora, CA48 of 4954.1 ppb10,814
US Air Force AcademyUsaf Academy, CO48 of 4853.1 ppb16,876
College Utilities Corporation*Fairbanks, AK48 of 4952.7 ppb13,000
James Fork Regional Water District*Greenwood, AR51 of 5152.6 ppb11,380
Cunningham Utility District*Clarksville, TN56 of 5652.1 ppb15,755
Guilderland Town WDGuilderland, NY44 of 4452.0 ppb30,000
Orange Vale Water CompanyOrangevale, CA16 of 1652.0 ppb16,861
San Juan Water District*Granite Bay, CA16 of 1652.0 ppb28,971
Citrus Heights Water District*Citrus Heights, CA16 of 1652.0 ppb66,815
Montgomery County Water System*Mt Gilead, NC51 of 5151.6 ppb14,710
Clarksburg Water Board*Clarksburg, WV52 of 5251.4 ppb47,689
Wisconsin Rapids Water Works & Lighting Comm.Wisconsin Rapids, WI53 of 5351.4 ppb20,000
Eatonton Putnam Water & Sewer AuthorityEatonton, GA23 of 2351.4 ppb11,479
Lee Water District*Lee Center, NY12 of 1251.2 ppb36,000
Community Water System*Greers Ferry, AR50 of 5051.1 ppb17,412
East ProvidenceEast Providence, RI48 of 4850.5 ppb47,618
North Table Mountain WSDGolden, CO51 of 5150.3 ppb10,000
Lincoln Water CommissionLincoln, RI48 of 4850.1 ppb21,664
E Stroudsburg Boro Water Dept*East Stroudsburg, PA48 of 4850.0 ppb13,000
Cedar Grove Water DepartmentCedar Grove, NJ48 of 4849.9 ppb12,900
Wayne Township Division of WaterWayne, NJ96 of 9649.8 ppb55,000
MVWA - Mohawk Valley Water Authority*Utica, NY97 of 9749.8 ppb129,372
Verona Water Department*Chatham, NJ48 of 4849.8 ppb13,641
Buchanan County PSA*Vansant, VA48 of 4849.8 ppb19,326
Claremore*Claremore, OK65 of 6549.7 ppb15,873
Valdosta*Valdosta, GA49 of 4949.4 ppb48,959

* This water utility supplies finished drinking water to at least one other water utility. The purchasing utility is not required to test for or report Chloroform, but it likely has the contaminant in its water supply.

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