Haloacetic acids (HAA5)
Walker Water System
Haloacetic acids are formed when disinfectants such as chlorine are added to tap water. The group of five haloacetic acids regulated by federal standards includes monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid. Read More.
Haloacetic acids are harmful during pregnancy and may increase the risk of cancer. Haloacetic acids are� genotoxic, which means that they induce mutations and DNA damage. Multiple studies by the National Toxicology Program have demonstrated the cancer-causing properties of individual haloacetic acids in laboratory animals. The Department of Health and Human Services is currently considering listing di- or tri-haloacetic acids for possible inclusion in its comprehensive Report on Carcinogens.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2018 | 1.25 ppb | 32 | 22 | ND - 3.70 ppb |
| 2019 | 0.634 ppb | 32 | 24 | ND - 1.37 ppb |
| 2020 | 0.393 ppb | 16 | 9 | ND - 1.35 ppb |
| 2021 | 0.865 ppb | 16 | 7 | ND - 3.60 ppb |
| 2022 | 0.380 ppb | 16 | 6 | ND - 1.21 ppb |
| 2023 | 0.636 ppb | 16 | 4 | ND - 8.20 ppb |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 0.1 ppb
The EWG Health Guideline of 0.1 ppb for the group of five haloacetic acids, or HAA5, was defined in a peer-reviewed scientific study by EWG and represents a one-in-a-million lifetime cancer risk level. This health guideline protects against cancer.
EPA Maximum Contaminant
Level (MCL): 60 ppb
The legal limit for the group of five haloacetic acids (HAA5), established in 1998, was based on the need for residual disinfectant levels in water served to customers and the cost of treatment. This limit does not fully protect against the risk of cancer and harm to the developing fetus due to exposure to haloacetic acids.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-02-02 | 35371888001 | ND |
| 2018-02-02 | 35371888002 | ND |
| 2018-02-02 | 35371888003 | ND |
| 2018-02-02 | 35371888004 | ND |
| 2018-02-02 | 35371888001 | ND |
| 2018-02-02 | 35371888002 | ND |
| 2018-02-02 | 35371888003 | ND |
| 2018-02-02 | 35371888004 | ND |
| 2018-05-03 | 35390312001 | 3.10 ppb |
| 2018-05-03 | 35390312002 | 3.10 ppb |
| 2018-05-03 | 35390312003 | 3.70 ppb |
| 2018-05-03 | 35390312004 | 2.70 ppb |
| 2018-05-03 | 35390312001 | 3.10 ppb |
| 2018-05-03 | 35390312002 | 3.10 ppb |
| 2018-05-03 | 35390312003 | 3.70 ppb |
| 2018-05-03 | 35390312004 | 2.70 ppb |
| 2018-08-07 | 35409811001 | 0.960 ppb |
| 2018-08-07 | 35409811002 | ND |
| 2018-08-07 | 35409811003 | 0.810 ppb |
| 2018-08-07 | 35409811004 | 0.830 ppb |
| 2018-08-07 | 35409811001 | 0.960 ppb |
| 2018-08-07 | 35409811002 | ND |
| 2018-08-07 | 35409811003 | 0.810 ppb |
| 2018-08-07 | 35409811004 | 0.830 ppb |
| 2018-11-01 | 35428050001 | 1.50 ppb |
| 2018-11-01 | 35428050002 | 1.40 ppb |
| 2018-11-01 | 35428050003 | 0.950 ppb |
| 2018-11-01 | 35428050004 | 0.930 ppb |
| 2018-11-01 | 35428050001 | 1.50 ppb |
| 2018-11-01 | 35428050002 | 1.40 ppb |
| 2018-11-01 | 35428050003 | 0.950 ppb |
| 2018-11-01 | 35428050004 | 0.930 ppb |
| 2019-02-14 | 35448843001 | 1.20 ppb |
| 2019-02-14 | 35448843002 | 0.840 ppb |
| 2019-02-14 | 35448843003 | 1.30 ppb |
| 2019-02-14 | 35448843004 | 1.30 ppb |
| 2019-02-14 | 35448843001 | 1.20 ppb |
| 2019-02-14 | 35448843002 | 0.840 ppb |
| 2019-02-14 | 35448843003 | 1.30 ppb |
| 2019-02-14 | 35448843004 | 1.30 ppb |
| 2019-05-15 | 35469379001 | 0.370 ppb |
| 2019-05-15 | 35469379002 | 0.810 ppb |
| 2019-05-15 | 35469379003 | 0.550 ppb |
| 2019-05-15 | 35469379004 | 1.37 ppb |
| 2019-05-15 | 35469379001 | 0.370 ppb |
| 2019-05-15 | 35469379002 | 0.810 ppb |
| 2019-05-15 | 35469379003 | 0.550 ppb |
| 2019-05-15 | 35469379004 | 1.37 ppb |
| 2019-08-01 | 35486873001 | 0.550 ppb |
| 2019-08-01 | 35486873002 | 0.760 ppb |
| 2019-08-01 | 35486873003 | 0.520 ppb |
| 2019-08-01 | 35486873004 | 0.580 ppb |
| 2019-08-01 | 35486873001 | 0.550 ppb |
| 2019-08-01 | 35486873002 | 0.760 ppb |
| 2019-08-01 | 35486873003 | 0.520 ppb |
| 2019-08-01 | 35486873004 | 0.580 ppb |
| 2019-11-07 | 35511062001 | ND |
| 2019-11-07 | 35511062002 | ND |
| 2019-11-07 | 35511062003 | ND |
| 2019-11-07 | 35511062004 | ND |
| 2019-11-07 | 35511062001 | ND |
| 2019-11-07 | 35511062002 | ND |
| 2019-11-07 | 35511062003 | ND |
| 2019-11-07 | 35511062004 | ND |
| 2020-02-06 | 35529496001 | 0.430 ppb |
| 2020-02-06 | 35529496002 | 0.950 ppb |
| 2020-02-06 | 35529496003 | 0.440 ppb |
| 2020-02-06 | 35529496004 | 1.35 ppb |
| 2020-05-08 | 35548831001 | ND |
| 2020-05-08 | 35548831002 | ND |
| 2020-05-08 | 35548831003 | ND |
| 2020-05-08 | 35548831004 | ND |
| 2020-08-06 | 35569084001 | 0.300 ppb |
| 2020-08-06 | 35569084002 | ND |
| 2020-08-06 | 35569084003 | ND |
| 2020-08-06 | 35569084004 | 0.480 ppb |
| 2020-11-06 | 35590483001 | 0.820 ppb |
| 2020-11-06 | 35590483002 | 0.730 ppb |
| 2020-11-06 | 35590483003 | ND |
| 2020-11-06 | 35590483004 | 0.780 ppb |
| 2021-02-05 | 35610002001 | ND |
| 2021-02-05 | 35610002002 | ND |
| 2021-02-05 | 35610002003 | ND |
| 2021-02-05 | 35610002004 | ND |
| 2021-05-06 | 35631659001 | ND |
| 2021-05-06 | 35631659002 | ND |
| 2021-05-06 | 35631659003 | 0.560 ppb |
| 2021-05-06 | 35631659004 | 0.390 ppb |
| 2021-08-05 | 35653771001 | 3.60 ppb |
| 2021-08-05 | 35653771002 | 3.10 ppb |
| 2021-08-05 | 35653771003 | 3.20 ppb |
| 2021-08-05 | 35653771004 | 2.70 ppb |
| 2021-11-05 | 35676292001 | ND |
| 2021-11-05 | 35676292002 | 0.290 ppb |
| 2021-11-05 | 35676292003 | ND |
| 2021-11-05 | 35676292004 | ND |
| 2022-02-10 | 35696562005 | 1.01 ppb |
| 2022-02-10 | 35696562006 | 1.14 ppb |
| 2022-02-10 | 35696562007 | 0.990 ppb |
| 2022-02-10 | 35696562008 | 1.21 ppb |
| 2022-05-06 | 35715922001 | ND |
| 2022-05-06 | 35715922002 | 0.980 ppb |
| 2022-05-06 | 35715922003 | ND |
| 2022-05-06 | 35715922004 | 0.750 ppb |
| 2022-08-17 | 35741191001 | ND |
| 2022-08-17 | 35741191002 | ND |
| 2022-08-17 | 35741191003 | ND |
| 2022-08-17 | 35741191004 | ND |
| 2022-11-04 | 35758151001 | ND |
| 2022-11-04 | 35758151002 | ND |
| 2022-11-04 | 35758151003 | ND |
| 2022-11-04 | 35758151004 | ND |
| 2023-02-03 | 35776989001 | ND |
| 2023-02-03 | 35776989002 | ND |
| 2023-02-03 | 35776989003 | ND |
| 2023-02-03 | 35776989004 | ND |
| 2023-05-05 | 35797785001 | ND |
| 2023-05-05 | 35797785002 | ND |
| 2023-05-05 | 35797785003 | ND |
| 2023-05-05 | 35797785004 | ND |
| 2023-08-02 | 35818085001 | 0.620 ppb |
| 2023-08-02 | 35818085002 | 0.710 ppb |
| 2023-08-02 | 35818085003 | 0.650 ppb |
| 2023-08-02 | 35818085004 | 8.20 ppb |
| 2023-11-03 | 35839250001 | ND |
| 2023-11-03 | 35839250002 | ND |
| 2023-11-03 | 35839250003 | ND |
| 2023-11-03 | 35839250004 | ND |