Dichloroacetic acid
St John Water District 3
Dichloroacetic acid, one of the group of five haloacetic acids regulated by federal standards, is formed when chlorine or other disinfectants are used to treat drinking water. Haloacetic acids and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.
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 | 1.69 ppb | 32 | 22 | ND - 11.2 ppb |
| 2019 | 0.159 ppb | 32 | 12 | ND - 0.860 ppb |
| 2020 | 0.291 ppb | 16 | 9 | ND - 0.860 ppb |
| 2021 | 0.538 ppb | 16 | 11 | ND - 1.50 ppb |
| 2022 | 1.07 ppb | 20 | 16 | ND - 2.30 ppb |
| 2023 | 0.890 ppb | 16 | 12 | ND - 1.80 ppb |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 0.2 ppb
The EWG Health Guideline of 0.2 ppb for dichloroacetic acid was defined by 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 reproduction and child development.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-03-15 | 35380541001 | ND |
| 2018-03-15 | 35380541002 | ND |
| 2018-03-15 | 35380541003 | ND |
| 2018-03-15 | 35380541004 | ND |
| 2018-03-15 | 35380541001 | ND |
| 2018-03-15 | 35380541002 | ND |
| 2018-03-15 | 35380541003 | ND |
| 2018-03-15 | 35380541004 | ND |
| 2018-06-14 | 35398653001 | 0.700 ppb |
| 2018-06-14 | 35398653002 | 0.610 ppb |
| 2018-06-14 | 35398653003 | 0.620 ppb |
| 2018-06-14 | 35398653004 | 0.480 ppb |
| 2018-06-14 | 35398653001 | 0.700 ppb |
| 2018-06-14 | 35398653002 | 0.610 ppb |
| 2018-06-14 | 35398653003 | 0.620 ppb |
| 2018-06-14 | 35398653004 | 0.480 ppb |
| 2018-09-06 | 35416144001 | 0.530 ppb |
| 2018-09-06 | 35416144002 | 0.600 ppb |
| 2018-09-06 | 35416144003 | 0.410 ppb |
| 2018-09-06 | 35416144001 | 0.530 ppb |
| 2018-09-06 | 35416144002 | 0.600 ppb |
| 2018-09-06 | 35416144003 | 0.410 ppb |
| 2018-09-20 | 35419461001 | ND |
| 2018-09-20 | 35419461001 | ND |
| 2018-12-10 | 35436358001 | 0.720 ppb |
| 2018-12-10 | 35436358002 | 0.710 ppb |
| 2018-12-10 | 35436358003 | 10.5 ppb |
| 2018-12-10 | 35436358004 | 11.2 ppb |
| 2018-12-10 | 35436358001 | 0.720 ppb |
| 2018-12-10 | 35436358002 | 0.710 ppb |
| 2018-12-10 | 35436358003 | 10.5 ppb |
| 2018-12-10 | 35436358004 | 11.2 ppb |
| 2019-03-13 | 35454558001 | ND |
| 2019-03-13 | 35454558002 | ND |
| 2019-03-13 | 35454558003 | ND |
| 2019-03-13 | 35454558004 | ND |
| 2019-03-13 | 35454558001 | ND |
| 2019-03-13 | 35454558002 | ND |
| 2019-03-13 | 35454558003 | ND |
| 2019-03-13 | 35454558004 | ND |
| 2019-06-11 | 35475282001 | 0.360 ppb |
| 2019-06-11 | 35475282002 | 0.340 ppb |
| 2019-06-11 | 35475282003 | 0.330 ppb |
| 2019-06-11 | 35475282004 | 0.320 ppb |
| 2019-06-11 | 35475282001 | 0.360 ppb |
| 2019-06-11 | 35475282002 | 0.340 ppb |
| 2019-06-11 | 35475282003 | 0.330 ppb |
| 2019-06-11 | 35475282004 | 0.320 ppb |
| 2019-09-12 | 35497592001 | 0.330 ppb |
| 2019-09-12 | 35497592002 | ND |
| 2019-09-12 | 35497592003 | 0.860 ppb |
| 2019-09-12 | 35497592004 | ND |
| 2019-09-12 | 35497592001 | 0.330 ppb |
| 2019-09-12 | 35497592002 | ND |
| 2019-09-12 | 35497592003 | 0.860 ppb |
| 2019-09-12 | 35497592004 | ND |
| 2019-12-09 | 35517589001 | ND |
| 2019-12-09 | 35517589002 | ND |
| 2019-12-09 | 35517589003 | ND |
| 2019-12-09 | 35517589004 | ND |
| 2019-12-09 | 35517589001 | ND |
| 2019-12-09 | 35517589002 | ND |
| 2019-12-09 | 35517589003 | ND |
| 2019-12-09 | 35517589004 | ND |
| 2020-03-11 | 35537037001 | 0.860 ppb |
| 2020-03-11 | 35537037002 | 0.650 ppb |
| 2020-03-11 | 35537037003 | 0.720 ppb |
| 2020-03-11 | 35537037004 | 0.690 ppb |
| 2020-06-11 | 35556251001 | 0.310 ppb |
| 2020-06-11 | 35556251002 | 0.400 ppb |
| 2020-06-11 | 35556251003 | ND |
| 2020-06-11 | 35556251004 | 0.350 ppb |
| 2020-09-03 | 35575676001 | ND |
| 2020-09-03 | 35575676002 | ND |
| 2020-09-03 | 35575676003 | ND |
| 2020-09-03 | 35575676004 | ND |
| 2020-12-10 | 35598317001 | ND |
| 2020-12-10 | 35598317002 | ND |
| 2020-12-10 | 35598317003 | 0.290 ppb |
| 2020-12-10 | 35598317004 | 0.380 ppb |
| 2021-03-19 | 35620546001 | ND |
| 2021-03-19 | 35620546002 | ND |
| 2021-03-19 | 35620546003 | ND |
| 2021-03-19 | 35620546004 | ND |
| 2021-06-30 | 35644466001 | 0.370 ppb |
| 2021-06-30 | 35644466002 | 0.270 ppb |
| 2021-06-30 | 35644466003 | 0.550 ppb |
| 2021-06-30 | 35644466004 | 0.290 ppb |
| 2021-09-24 | 35667106001 | 0.620 ppb |
| 2021-09-24 | 35667106002 | 0.630 ppb |
| 2021-09-24 | 35667106003 | ND |
| 2021-09-24 | 35667106004 | 0.680 ppb |
| 2021-12-21 | 35686306001 | 1.50 ppb |
| 2021-12-21 | 35686306002 | 1.40 ppb |
| 2021-12-21 | 35686306003 | 1.20 ppb |
| 2021-12-21 | 35686306004 | 1.10 ppb |
| 2022-03-10 | 35702952001 | 1.10 ppb |
| 2022-03-10 | 35702952002 | 0.930 ppb |
| 2022-03-10 | 35702952003 | 0.710 ppb |
| 2022-03-10 | 35702952004 | 0.660 ppb |
| 2022-06-08 | B2202690-001 | ND |
| 2022-06-08 | B2202690-002 | ND |
| 2022-06-08 | B2202690-003 | ND |
| 2022-06-08 | B2202690-004 | ND |
| 2022-07-25 | 35734268001 | 1.30 ppb |
| 2022-07-25 | 35734268002 | 1.20 ppb |
| 2022-07-25 | 35734268003 | 1.70 ppb |
| 2022-07-25 | 35734268004 | 1.40 ppb |
| 2022-09-07 | 35745058001 | 1.000 ppb |
| 2022-09-07 | 35745058002 | 1.40 ppb |
| 2022-09-07 | 35745058003 | 1.50 ppb |
| 2022-09-07 | 35745058004 | 1.10 ppb |
| 2022-12-01 | 35763427001 | 2.30 ppb |
| 2022-12-01 | 35763427002 | 2.00 ppb |
| 2022-12-01 | 35763427003 | 1.70 ppb |
| 2022-12-01 | 35763427004 | 1.30 ppb |
| 2023-03-16 | 35786622001 | 1.30 ppb |
| 2023-03-16 | 35786622002 | 1.70 ppb |
| 2023-03-16 | 35786622003 | 1.70 ppb |
| 2023-03-16 | 35786622004 | 1.40 ppb |
| 2023-06-21 | 35808368001 | 1.10 ppb |
| 2023-06-21 | 35808368002 | 1.50 ppb |
| 2023-06-21 | 35808368004 | 1.80 ppb |
| 2023-06-29 | 35809952001 | 1.10 ppb |
| 2023-09-18 | 35828420001 | ND |
| 2023-09-18 | 35828420002 | ND |
| 2023-09-18 | 35828420003 | ND |
| 2023-09-18 | 35828420004 | ND |
| 2023-12-27 | 35850590001 | 0.650 ppb |
| 2023-12-27 | 35850590002 | 0.650 ppb |
| 2023-12-27 | 35850590003 | 0.730 ppb |
| 2023-12-27 | 35850590004 | 0.610 ppb |