Chromium (hexavalent)
California Water Service Company Oak Hills
Chromium (hexavalent) is a carcinogen that commonly contaminates American drinking water. Chromium (hexavalent) in drinking water may be due to industrial pollution or natural occurrences in mineral deposits and groundwater. Read more about chromium (hexavalent).
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2013 | N/A | 0 | 0 | N/A |
| 2014 | N/A | 0 | 0 | N/A |
| 2015 | N/A | 0 | 0 | N/A |
| 2016 | N/A | 0 | 0 | N/A |
| 2017 | N/A | 0 | 0 | N/A |
| 2018 | 9.39 ppb | 29 | 29 | 4.00 ppb - 12.0 ppb |
| 2019 | 8.92 ppb | 25 | 25 | 5.00 ppb - 12.0 ppb |
| 2020 | 8.81 ppb | 16 | 16 | 5.40 ppb - 12.0 ppb |
| 2021 | 8.94 ppb | 25 | 25 | 5.90 ppb - 13.0 ppb |
| 2022 | 9.17 ppb | 26 | 26 | 5.30 ppb - 12.0 ppb |
| 2023 | 9.66 ppb | 28 | 28 | 5.50 ppb - 12.0 ppb |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 0.02 ppb
The EWG Health Guideline of 0.02 ppb for chromium (hexavalent) was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-01-03 | CA2710019_003_003-201801030948 | 12.0 ppb |
| 2018-01-03 | CA2710019_010_010-201801030947 | 7.60 ppb |
| 2018-02-13 | CA2710019_010_010-201802131001 | 7.00 ppb |
| 2018-02-13 | CA2710019_003_003-201802131000 | 12.0 ppb |
| 2018-03-05 | CA2710019_010_010-201803051054 | 6.80 ppb |
| 2018-03-05 | CA2710019_003_003-201803051053 | 12.0 ppb |
| 2018-04-02 | CA2710019_010_010-201804021027 | 7.70 ppb |
| 2018-04-02 | CA2710019_003_003-201804021028 | 12.0 ppb |
| 2018-05-08 | CA2710019_003_003-201805081301 | 12.0 ppb |
| 2018-05-08 | CA2710019_010_010-201805081303 | 12.0 ppb |
| 2018-06-05 | CA2710019_010_010-201806050940 | 9.60 ppb |
| 2018-06-05 | CA2710019_003_003-201806050939 | 11.0 ppb |
| 2018-07-05 | CA2710019_003_003-201807051321 | 11.0 ppb |
| 2018-07-05 | CA2710019_010_010-201807051322 | 11.0 ppb |
| 2018-07-31 | CA2710019_010_010-201807311259 | 8.20 ppb |
| 2018-08-07 | CA2710019_010_010-201808071340 | 10.00 ppb |
| 2018-08-07 | CA2710019_003_003-201808071339 | 11.0 ppb |
| 2018-09-04 | CA2710019_010_010-201809040915 | 7.40 ppb |
| 2018-09-04 | CA2710019_003_003-201809040913 | 11.0 ppb |
| 2018-10-02 | CA2710019_003_003-201810021004 | 11.0 ppb |
| 2018-10-02 | CA2710019_010_010-201810021005 | 5.50 ppb |
| 2018-10-16 | CA2710019_003_003-201810161029 | 11.0 ppb |
| 2018-10-16 | CA2710019_010_010-201810161032 | 5.90 ppb |
| 2018-10-22 | CA2710019_010_010-201810220945 | 5.60 ppb |
| 2018-10-22 | CA2710019_003_003-201810220948 | 11.0 ppb |
| 2018-11-05 | CA2710019_010_010-201811051119 | 4.00 ppb |
| 2018-11-05 | CA2710019_003_003-201811051120 | 11.0 ppb |
| 2018-12-05 | CA2710019_010_010-201812051031 | 5.10 ppb |
| 2018-12-05 | CA2710019_003_003-201812051030 | 11.0 ppb |
| 2019-01-09 | CA2710019_003_003-201901091104 | 11.0 ppb |
| 2019-01-09 | CA2710019_010_010-201901091103 | 5.90 ppb |
| 2019-02-05 | CA2710019_010_010-201902050904 | 6.00 ppb |
| 2019-02-05 | CA2710019_003_003-201902050902 | 12.0 ppb |
| 2019-03-04 | CA2710019_003_003-201903041046 | 11.0 ppb |
| 2019-03-04 | CA2710019_010_010-201903041047 | 5.20 ppb |
| 2019-04-09 | CA2710019_003_003-201904090934 | 11.0 ppb |
| 2019-04-09 | CA2710019_010_010-201904090932 | 6.00 ppb |
| 2019-05-07 | CA2710019_010_010-201905070948 | 7.30 ppb |
| 2019-05-07 | CA2710019_003_003-201905070949 | 11.0 ppb |
| 2019-06-05 | CA2710019_008_008-201906051004 | 11.0 ppb |
| 2019-06-05 | CA2710019_010_010-201906050940 | 5.70 ppb |
| 2019-06-05 | CA2710019_003_003-201906050938 | 12.0 ppb |
| 2019-07-11 | CA2710019_010_010-201907110917 | 6.20 ppb |
| 2019-07-23 | CA2710019_003_003-201907231205 | 12.0 ppb |
| 2019-08-06 | CA2710019_003_003-201908061006 | 12.0 ppb |
| 2019-08-06 | CA2710019_010_010-201908061007 | 7.20 ppb |
| 2019-09-04 | CA2710019_003_003-201909041254 | 11.0 ppb |
| 2019-09-04 | CA2710019_010_010-201909041255 | 6.60 ppb |
| 2019-10-07 | CA2710019_003_003-201910071239 | 12.0 ppb |
| 2019-10-07 | CA2710019_010_010-201910071240 | 6.70 ppb |
| 2019-11-05 | CA2710019_010_010-201911050943 | 5.00 ppb |
| 2019-11-05 | CA2710019_003_003-201911050944 | 11.0 ppb |
| 2019-12-05 | CA2710019_010_010-201912051249 | 6.30 ppb |
| 2019-12-05 | CA2710019_003_003-201912051248 | 12.0 ppb |
| 2020-01-08 | CA2710019_010_010-202001081122 | 6.70 ppb |
| 2020-01-28 | CA2710019_003_003-202001281408 | 12.0 ppb |
| 2020-02-04 | CA2710019_010_010-202002041054 | 6.50 ppb |
| 2020-02-04 | CA2710019_003_003-202002041053 | 11.0 ppb |
| 2020-03-04 | CA2710019_003_003-202003040928 | 12.0 ppb |
| 2020-03-04 | CA2710019_010_010-202003040931 | 5.80 ppb |
| 2020-04-08 | CA2710019_003_003-202004081344 | 12.0 ppb |
| 2020-04-08 | CA2710019_010_010-202004081345 | 5.40 ppb |
| 2020-09-16 | CA2710019_003_003-202009161150 | 11.0 ppb |
| 2020-09-16 | CA2710019_010_010-202009161148 | 6.10 ppb |
| 2020-10-07 | CA2710019_003_003-202010070928 | 11.0 ppb |
| 2020-10-07 | CA2710019_010_010-202010070932 | 6.70 ppb |
| 2020-11-05 | CA2710019_010_010-202011051425 | 6.60 ppb |
| 2020-11-05 | CA2710019_003_003-202011051424 | 11.0 ppb |
| 2020-12-09 | CA2710019_003_003-202012091322 | 11.0 ppb |
| 2020-12-09 | CA2710019_010_010-202012091325 | 6.20 ppb |
| 2021-01-11 | CA2710019_003_003-202101111021 | 11.0 ppb |
| 2021-01-11 | CA2710019_010_010-202101111022 | 6.40 ppb |
| 2021-02-11 | CA2710019_010_010-202102111148 | 5.90 ppb |
| 2021-02-11 | CA2710019_003_003-202102111146 | 11.0 ppb |
| 2021-03-02 | CA2710019_003_003-202103021348 | 11.0 ppb |
| 2021-03-02 | CA2710019_010_010-202103021349 | 6.10 ppb |
| 2021-04-20 | CA2710019_010_010-202104200920 | 8.90 ppb |
| 2021-04-20 | CA2710019_003_003-202104200919 | 11.0 ppb |
| 2021-05-04 | CA2710019_003_003-202105040941 | 11.0 ppb |
| 2021-05-04 | CA2710019_010_010-202105040943 | 8.00 ppb |
| 2021-06-03 | CA2710019_003_003-202106031158 | 12.0 ppb |
| 2021-06-03 | CA2710019_010_010-202106031200 | 7.80 ppb |
| 2021-07-20 | CA2710019_003_003-202107201120 | 10.00 ppb |
| 2021-07-20 | CA2710019_010_010-202107201121 | 5.90 ppb |
| 2021-08-11 | CA2710019_003_003-202108110920 | 10.00 ppb |
| 2021-08-11 | CA2710019_010_010-202108110921 | 7.80 ppb |
| 2021-09-14 | CA2710019_010_010-202109140939 | 7.20 ppb |
| 2021-09-14 | CA2710019_003_003-202109140938 | 10.00 ppb |
| 2021-09-22 | CA2710019_001_001-202109221104 | 6.30 ppb |
| 2021-10-12 | CA2710019_010_010-202110121248 | 7.20 ppb |
| 2021-10-12 | CA2710019_003_003-202110121249 | 11.0 ppb |
| 2021-11-18 | CA2710019_003_003-202111181023 | 11.0 ppb |
| 2021-11-18 | CA2710019_010_010-202111181025 | 6.00 ppb |
| 2021-12-13 | CA2710019_003_003-202112130943 | 13.0 ppb |
| 2021-12-13 | CA2710019_010_010-202112130944 | 8.00 ppb |
| 2022-01-13 | CA2710019_010_010-202201130944 | 6.60 ppb |
| 2022-01-13 | CA2710019_003_003-202201130948 | 10.00 ppb |
| 2022-02-01 | CA2710019_003_003-202202011039 | 11.0 ppb |
| 2022-02-01 | CA2710019_010_010-202202011040 | 6.90 ppb |
| 2022-03-08 | CA2710019_010_010-202203080927 | 7.30 ppb |
| 2022-03-08 | CA2710019_003_003-202203080926 | 10.00 ppb |
| 2022-04-18 | CA2710019_010_010-202204180928 | 7.40 ppb |
| 2022-04-18 | CA2710019_003_003-202204180924 | 10.00 ppb |
| 2022-05-03 | CA2710019_003_003-202205030943 | 10.00 ppb |
| 2022-05-03 | CA2710019_010_010-202205030944 | 6.70 ppb |
| 2022-06-22 | CA2710019_008_008-202206221337 | 10.00 ppb |
| 2022-06-29 | CA2710019_008_008-202206291348 | 10.00 ppb |
| 2022-06-29 | CA2710019_010_010-202206291404 | 5.30 ppb |
| 2022-06-29 | CA2710019_003_003-202206291402 | 12.0 ppb |
| 2022-07-28 | CA2710019_003_003-202207281146 | 12.0 ppb |
| 2022-07-28 | CA2710019_010_010-202207281147 | 7.30 ppb |
| 2022-08-09 | CA2710019_003_003-202208091056 | 11.0 ppb |
| 2022-08-09 | CA2710019_010_010-202208091057 | 8.30 ppb |
| 2022-09-07 | CA2710019_003_003-202209070933 | 12.0 ppb |
| 2022-09-07 | CA2710019_010_010-202209070934 | 7.80 ppb |
| 2022-10-06 | CA2710019_010_010-202210061421 | 9.00 ppb |
| 2022-10-06 | CA2710019_003_003-202210061420 | 11.0 ppb |
| 2022-11-03 | CA2710019_003_003-202211031154 | 11.0 ppb |
| 2022-11-03 | CA2710019_010_010-202211031156 | 7.40 ppb |
| 2022-12-06 | CA2710019_010_010-202212061330 | 6.50 ppb |
| 2022-12-06 | CA2710019_003_003-202212061330 | 12.0 ppb |
| 2023-01-04 | CA2710019_003_003-202301041200 | 12.0 ppb |
| 2023-01-04 | CA2710019_010_010-202301041201 | 6.30 ppb |
| 2023-01-26 | CA2710019_008_008-202301261258 | 11.0 ppb |
| 2023-02-07 | CA2710019_003_003-202302071120 | 11.0 ppb |
| 2023-02-07 | CA2710019_010_010-202302071121 | 5.50 ppb |
| 2023-03-08 | CA2710019_003_003-202303081054 | 11.0 ppb |
| 2023-03-08 | CA2710019_010_010-202303081100 | 6.70 ppb |
| 2023-04-11 | CA2710019_003_003-202304111153 | 12.0 ppb |
| 2023-04-11 | CA2710019_010_010-202304111154 | 6.40 ppb |
| 2023-04-12 | CA2710019_008_008-202304121049 | 11.0 ppb |
| 2023-05-02 | CA2710019_010_010-202305021132 | 7.00 ppb |
| 2023-05-02 | CA2710019_003_003-202305021131 | 11.0 ppb |
| 2023-06-12 | CA2710019_010_010-202306120941 | 7.30 ppb |
| 2023-06-12 | CA2710019_003_003-202306120940 | 12.0 ppb |
| 2023-07-10 | CA2710019_003_003-202307101100 | 12.0 ppb |
| 2023-07-10 | CA2710019_010_010-202307101101 | 7.80 ppb |
| 2023-07-20 | CA2710019_008_008-202307201000 | 11.0 ppb |
| 2023-08-10 | CA2710019_003_003-202308100916 | 12.0 ppb |
| 2023-08-10 | CA2710019_010_010-202308100918 | 9.80 ppb |
| 2023-09-13 | CA2710019_010_010-202309130925 | 8.20 ppb |
| 2023-09-13 | CA2710019_003_003-202309130924 | 11.0 ppb |
| 2023-10-19 | CA2710019_003_003-202310190913 | 11.0 ppb |
| 2023-10-19 | CA2710019_010_010-202310190914 | 7.50 ppb |
| 2023-10-19 | CA2710019_008_008-202310190926 | 11.0 ppb |
| 2023-11-07 | CA2710019_003_003-202311071420 | 11.0 ppb |
| 2023-11-07 | CA2710019_010_010-202311071421 | 8.10 ppb |
| 2023-12-14 | CA2710019_003_003-202312141416 | 12.0 ppb |
| 2023-12-14 | CA2710019_010_010-202312141417 | 7.80 ppb |