EWG's Tap Water Database — 2021 UPDATE



Dewitt WDS - North

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. Read More.

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.





Samples exceeding legal limit (MCL)


Samples exceeding
health guidelines

Testing results - average by year

YearAverage resultSamples takenDetectionsRange of results
201420.9 ppb161614.0 ppb - 29.0 ppb
201516.6 ppb16167.80 ppb - 34.0 ppb
201620.2 ppb161610.00 ppb - 36.0 ppb
201730.3 ppb121220.0 ppb - 49.0 ppb
201821.0 ppb161615.0 ppb - 30.0 ppb
201926.3 ppb161617.0 ppb - 42.0 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.4 ppb

The EWG Health Guideline of 0.4 ppb for chloroform was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

ppb = parts per billion

All test results

Date Lab ID Result
2014-02-131Q2014 FLY RD26.0 ppb
2014-02-131Q2014 RUSSELL L14.0 ppb
2014-02-131Q2014 ALMONT DR18.0 ppb
2014-02-131Q2014 BADGELY R14.0 ppb
2014-05-132Q2014 FLY RD16.0 ppb
2014-05-132Q2014 BADGELY R18.0 ppb
2014-05-132Q2014 RUSSELL L25.0 ppb
2014-05-132Q2014 ALMONT DR24.0 ppb
2014-08-133Q2014 ALMONT DR29.0 ppb
2014-08-133Q2014 BADGELY R29.0 ppb
2014-08-133Q2014 RUSSELL L20.0 ppb
2014-08-133Q2014 FLY RD19.0 ppb
2014-11-134Q2014 RUSSELL L17.0 ppb
2014-11-134Q2014 FLY RD16.0 ppb
2014-11-134Q2014 BADGELY R22.0 ppb
2014-11-134Q2014 ALMONT DR28.0 ppb
2015-02-111Q2015 ALMONT DR9.90 ppb
2015-02-111Q2015 FLY RD7.80 ppb
2015-02-111Q2015 RUSSELL L9.10 ppb
2015-02-111Q2015 BADGELY R19.0 ppb
2015-05-142Q2015 RUSSELL L11.0 ppb
2015-05-142Q2015 FLY RD7.80 ppb
2015-05-142Q2015 ALMONT DR11.0 ppb
2015-05-142Q2015 BADGELY R13.0 ppb
2015-08-133Q2015 BADGELY R27.0 ppb
2015-08-133Q2015 ALMONT DR19.0 ppb
2015-08-133Q2015 RUSSELL L20.0 ppb
2015-08-133Q2015 FLY RD15.0 ppb
2015-11-094Q2015 RUSSELL L19.0 ppb
2015-11-094Q2015 FLY RD23.0 ppb
2015-11-094Q2015 BADGELY R34.0 ppb
2015-11-094Q2015 ALMONT DR20.0 ppb
2016-02-121Q2016 BADGELY R19.0 ppb
2016-02-121Q2016 FLY RD10.00 ppb
2016-02-121Q2016 ALMONT DR12.0 ppb
2016-02-121Q2016 RUSSELL L11.0 ppb
2016-05-172Q2016 RUSSELL L15.0 ppb
2016-05-172Q2016 BADGELY R20.0 ppb
2016-05-172Q2016 ALMONT DR14.0 ppb
2016-05-172Q2016 FLY RD11.0 ppb
2016-08-103Q2016 BADGELY R30.0 ppb
2016-08-103Q2016 RUSSELL L18.0 ppb
2016-08-103Q2016 FLY RD24.0 ppb
2016-08-103Q2016 ALMONT DR21.0 ppb
2016-11-084Q2016 RUSSELL L33.0 ppb
2016-11-084Q2016 BADGELY R36.0 ppb
2016-11-084Q2016 ALMONT DR22.0 ppb
2016-11-084Q2016 FLY RD27.0 ppb
2017-05-102Q2017 RUSSELL L25.0 ppb
2017-05-102Q2017 FLY RD32.0 ppb
2017-05-102Q2017 BADGELY R35.0 ppb
2017-05-102Q2017 ALMONT DR28.0 ppb
2017-08-093Q2017 FLY RD39.0 ppb
2017-08-093Q2017 RUSSELL L34.0 ppb
2017-08-093Q2017 ALMONT DR34.0 ppb
2017-08-093Q2017 BADGELY R49.0 ppb
2017-11-074Q2017 BADGELY R27.0 ppb
2017-11-074Q2017 ALMONT DR21.0 ppb
2017-11-074Q2017 RUSSELL L20.0 ppb
2017-11-074Q2017 FLY RD20.0 ppb
2018-02-151Q2018 RUSSELL L15.0 ppb
2018-02-151Q2018 BADGLEY R20.0 ppb
2018-02-151Q2018 ALMONT DR15.0 ppb
2018-02-151Q2018 FLY RD19.0 ppb
2018-05-102Q2018 ALMONT DR19.0 ppb
2018-05-102Q2018 BADGLEY R30.0 ppb
2018-05-102Q2018 FLY RD24.0 ppb
2018-05-102Q2018 RUSSELL L22.0 ppb
2018-08-143Q2018 BADGLEY R28.0 ppb
2018-08-143Q2018 RUSSELL L22.0 ppb
2018-08-143Q2018 ALMONT DR30.0 ppb
2018-08-143Q2018 FLY RD22.0 ppb
2018-11-074Q2018 FLY RD24.0 ppb
2018-11-074Q2018 BADGLEY R16.0 ppb
2018-11-074Q2018 ALMONT DR15.0 ppb
2018-11-074Q2018 RUSSELL L15.0 ppb
2019-02-141Q2019 ALMONT DR24.0 ppb
2019-02-141Q2019 BADGLEY R22.0 ppb
2019-02-141Q2019 FLY RD26.0 ppb
2019-02-141Q2019 RUSSELL L22.0 ppb
2019-05-102Q2019 FLY RD30.0 ppb
2019-05-102Q2019 RUSSELL L23.0 ppb
2019-05-102Q2019 ALMONT DR25.0 ppb
2019-05-102Q2019 BADGLEY R29.0 ppb
2019-08-133Q2019 RUSSELL L27.0 ppb
2019-08-133Q2019 FLY RD32.0 ppb
2019-08-133Q2019 ALMONT DR26.0 ppb
2019-08-133Q2019 BADGLEY R42.0 ppb
2019-11-064Q2019 RUSSELL L18.0 ppb
2019-11-064Q2019 BADGLEY R30.0 ppb
2019-11-064Q2019 ALMONT DR17.0 ppb
2019-11-064Q2019 FLY RD27.0 ppb