Arsenic
Ridgewood Water
Arsenic is a potent carcinogen and common contaminant in drinking water. Arsenic causes thousands of cases of cancer each year in the U.S. Click here to read more about arsenic.
350
Samples
0
Samples exceeding legal limit (MCL)
298
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2014 | 1.54 ppb | 52 | 46 | ND - 6.46 ppb |
| 2015 | 1.11 ppb | 54 | 43 | ND - 3.01 ppb |
| 2016 | 1.41 ppb | 58 | 56 | ND - 5.48 ppb |
| 2017 | 1.02 ppb | 64 | 45 | ND - 4.47 ppb |
| 2018 | 1.39 ppb | 65 | 55 | ND - 6.73 ppb |
| 2019 | 1.42 ppb | 57 | 53 | ND - 3.95 ppb |
ppb = parts per billion
State and national drinking water standards and health guidelines
EWG Health Guideline 0.004 ppb
The EWG Health Guideline of 0.004 ppb for arsenic 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.
EPA Maximum Contaminant
Level (MCL) 10 ppb
The legal limit for arsenic, established in 2001, was based on costs for arsenic removal, as calculated at the time that the standard was set. This limit does not fully protect against the risk of cancer due to arsenic exposure.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2014-03-05 | 4030099-08 | 1.75 ppb |
| 2014-03-05 | 4030099-05 | 2.89 ppb |
| 2014-03-05 | 4030099-06 | 6.46 ppb |
| 2014-03-05 | 4030099-03 | 1.40 ppb |
| 2014-03-05 | 4030099-09 | 3.05 ppb |
| 2014-03-05 | 4030099-07 | 3.66 ppb |
| 2014-03-05 | 4030099-01 | 2.03 ppb |
| 2014-03-05 | 4030099-02 | 1.63 ppb |
| 2014-03-05 | 4030099-11 | 2.89 ppb |
| 2014-03-05 | 4030099-04 | 1.75 ppb |
| 2014-03-05 | 4030099-10 | 3.72 ppb |
| 2014-05-28 | 4050791-09 | 1.51 ppb |
| 2014-05-28 | 4050791-01 | 1.94 ppb |
| 2014-05-28 | 4050791-04 | 1.54 ppb |
| 2014-05-28 | 4050791-02 | 4.06 ppb |
| 2014-05-28 | 4050791-03 | 1.03 ppb |
| 2014-05-28 | 4050791-06 | 1.26 ppb |
| 2014-05-28 | 4050791-05 | 2.86 ppb |
| 2014-05-28 | 4050791-07 | 1.46 ppb |
| 2014-05-28 | 4050791-08 | 0.971 ppb |
| 2014-07-09 | 4070294-06 | ND |
| 2014-07-09 | 4070294-14 | 1.56 ppb |
| 2014-07-09 | 4070294-07 | ND |
| 2014-07-09 | 4070294-04 | 2.97 ppb |
| 2014-07-09 | 4070294-01 | ND |
| 2014-07-09 | 4070294-08 | 0.829 ppb |
| 2014-07-09 | 4070294-02 | 1.39 ppb |
| 2014-07-09 | 4070294-05 | ND |
| 2014-07-09 | 4070294-03 | 0.591 ppb |
| 2014-07-09 | 4070294-09 | 0.681 ppb |
| 2014-07-09 | 4070294-12 | 0.708 ppb |
| 2014-07-09 | 4070294-11 | 0.977 ppb |
| 2014-07-09 | 4070294-10 | 1.37 ppb |
| 2014-07-09 | 4070294-13 | 0.573 ppb |
| 2014-07-23 | 4070750-04 | 1.17 ppb |
| 2014-07-23 | 4070750-02 | 1.30 ppb |
| 2014-07-23 | 4070750-05 | 0.989 ppb |
| 2014-07-23 | 4070750-01 | 2.24 ppb |
| 2014-07-23 | 4070750-06 | 2.30 ppb |
| 2014-07-23 | 4070750-03 | 1.54 ppb |
| 2014-10-29 | 4100857-04 | 0.531 ppb |
| 2014-10-29 | 4100857-03 | ND |
| 2014-10-29 | 4100857-05 | ND |
| 2014-10-29 | 4100857-12 | 2.49 ppb |
| 2014-10-29 | 4100857-01 | 1.27 ppb |
| 2014-10-29 | 4100857-08 | 2.00 ppb |
| 2014-10-29 | 4100857-09 | 1.49 ppb |
| 2014-10-29 | 4100857-02 | 0.743 ppb |
| 2014-10-29 | 4100857-07 | 0.696 ppb |
| 2014-10-29 | 4100857-06 | 0.556 ppb |
| 2014-10-29 | 4100857-10 | 0.728 ppb |
| 2014-10-29 | 4100857-11 | 0.534 ppb |
| 2015-03-09 | 5030145-09 | 0.701 ppb |
| 2015-03-09 | 5030145-02 | ND |
| 2015-03-09 | 5030145-01 | ND |
| 2015-03-09 | 5030145-04 | 0.930 ppb |
| 2015-03-09 | 5030145-06 | ND |
| 2015-03-09 | 5030145-11 | 1.88 ppb |
| 2015-03-09 | 5030145-05 | 1.32 ppb |
| 2015-03-09 | 5030145-08 | 0.880 ppb |
| 2015-03-09 | 5030145-07 | ND |
| 2015-03-09 | 5030145-03 | ND |
| 2015-03-09 | 5030145-10 | 2.26 ppb |
| 2015-03-10 | 5030178-01 | 1.25 ppb |
| 2015-03-30 | 5030652-01 | 2.87 ppb |
| 2015-03-31 | 5040020-01 | ND |
| 2015-05-12 | 5050322-09 | ND |
| 2015-05-12 | 5050322-03 | 2.09 ppb |
| 2015-05-12 | 5050322-06 | ND |
| 2015-05-12 | 5050322-01 | 3.01 ppb |
| 2015-05-12 | 5050322-08 | 1.12 ppb |
| 2015-05-12 | 5050322-07 | 1.06 ppb |
| 2015-05-12 | 5050322-02 | 2.22 ppb |
| 2015-05-12 | 5050322-10 | 0.756 ppb |
| 2015-05-13 | 5050377-01 | ND |
| 2015-06-09 | 5060246-08 | 0.947 ppb |
| 2015-07-15 | 5070473-07 | 0.663 ppb |
| 2015-07-15 | 5070473-03 | 2.04 ppb |
| 2015-07-15 | 5070473-05 | 2.87 ppb |
| 2015-07-15 | 5070473-01 | 0.570 ppb |
| 2015-07-15 | 5070473-08 | 1.08 ppb |
| 2015-07-15 | 5070473-02 | 1.56 ppb |
| 2015-07-15 | 5070473-06 | 1.45 ppb |
| 2015-07-15 | 5070473-04 | 1.13 ppb |
| 2015-07-15 | 5070473-10 | 1.07 ppb |
| 2015-07-15 | 5070473-09 | 2.18 ppb |
| 2015-07-15 | 5070473-13 | 1.35 ppb |
| 2015-07-15 | 5070473-12 | 1.19 ppb |
| 2015-07-15 | 5070473-11 | 1.92 ppb |
| 2015-07-15 | 5070473-14 | 1.30 ppb |
| 2015-07-16 | 5070495-01 | 0.740 ppb |
| 2015-10-14 | 5100424-04 | ND |
| 2015-10-14 | 5100424-03 | 0.637 ppb |
| 2015-10-14 | 5100424-10 | 1.43 ppb |
| 2015-10-14 | 5100424-05 | 0.594 ppb |
| 2015-10-14 | 5100424-01 | 1.34 ppb |
| 2015-10-14 | 5100424-09 | 1.47 ppb |
| 2015-10-14 | 5100424-02 | 0.664 ppb |
| 2015-10-14 | 5100424-07 | 0.882 ppb |
| 2015-10-14 | 5100424-06 | 2.38 ppb |
| 2015-10-14 | 5100424-08 | 0.620 ppb |
| 2015-10-21 | 5100667-03 | 2.97 ppb |
| 2015-10-21 | 5100667-02 | 0.834 ppb |
| 2015-10-21 | 5100667-04 | 0.888 ppb |
| 2015-10-21 | 5100667-01 | 1.07 ppb |
| 2015-12-29 | 5120773-02 | ND |
| 2016-01-07 | 6010110-06 | 0.625 ppb |
| 2016-01-07 | 6010110-01 | 2.70 ppb |
| 2016-01-07 | 6010110-07 | 0.804 ppb |
| 2016-01-07 | 6010110-04 | 5.48 ppb |
| 2016-01-07 | 6010110-02 | 1.11 ppb |
| 2016-01-07 | 6010110-05 | 0.947 ppb |
| 2016-01-07 | 6010110-03 | 0.820 ppb |
| 2016-01-07 | 6010110-09 | 1.53 ppb |
| 2016-01-07 | 6010110-10 | 0.787 ppb |
| 2016-01-07 | 6010110-11 | 1.29 ppb |
| 2016-01-07 | 6010110-08 | 1.44 ppb |
| 2016-01-07 | 6010110-12 | 1.27 ppb |
| 2016-01-08 | 6010173-01 | 0.984 ppb |
| 2016-01-08 | 6010173-02 | 2.56 ppb |
| 2016-01-19 | 6010438-01 | 1.97 ppb |
| 2016-04-06 | 6040180-04 | 0.647 ppb |
| 2016-04-06 | 6040180-06 | 1.98 ppb |
| 2016-04-06 | 6040180-05 | ND |
| 2016-04-06 | 6040180-02 | 4.15 ppb |
| 2016-04-06 | 6040180-03 | 1.42 ppb |
| 2016-04-06 | 6040180-01 | 1.79 ppb |
| 2016-04-06 | 6040180-08 | 0.935 ppb |
| 2016-04-06 | 6040180-07 | 2.38 ppb |
| 2016-04-06 | 6040180-09 | 0.745 ppb |
| 2016-04-19 | 6040629-02 | 1.26 ppb |
| 2016-04-19 | 6040629-01 | 1.16 ppb |
| 2016-05-03 | 6050075-01 | 1.90 ppb |
| 2016-05-11 | 6050372-04 | 0.895 ppb |
| 2016-07-06 | 6070112-06 | ND |
| 2016-07-06 | 6070112-09 | 1.56 ppb |
| 2016-07-06 | 6070112-07 | 0.568 ppb |
| 2016-07-06 | 6070112-04 | 3.11 ppb |
| 2016-07-06 | 6070112-01 | 1.76 ppb |
| 2016-07-06 | 6070112-08 | 0.864 ppb |
| 2016-07-06 | 6070112-02 | 1.90 ppb |
| 2016-07-06 | 6070112-05 | 0.918 ppb |
| 2016-07-06 | 6070112-03 | 0.610 ppb |
| 2016-07-06 | 6070112-11 | 0.986 ppb |
| 2016-07-06 | 6070112-10 | 2.39 ppb |
| 2016-07-06 | 6070112-14 | 0.923 ppb |
| 2016-07-06 | 6070112-13 | 1.000 ppb |
| 2016-07-06 | 6070112-12 | 1.65 ppb |
| 2016-07-06 | 6070112-15 | 1.15 ppb |
| 2016-10-11 | 6100288-07 | 0.554 ppb |
| 2016-10-11 | 6100288-06 | 0.752 ppb |
| 2016-10-11 | 6100288-11 | 2.29 ppb |
| 2016-10-11 | 6100288-08 | 0.568 ppb |
| 2016-10-11 | 6100288-04 | 1.41 ppb |
| 2016-10-11 | 6100288-03 | 3.30 ppb |
| 2016-10-11 | 6100288-09 | 0.933 ppb |
| 2016-10-11 | 6100288-01 | 1.67 ppb |
| 2016-10-11 | 6100288-05 | 0.778 ppb |
| 2016-10-11 | 6100288-02 | 0.798 ppb |
| 2016-10-11 | 6100288-10 | 0.798 ppb |
| 2016-10-11 | 6100288-13 | 0.913 ppb |
| 2016-10-11 | 6100288-12 | 2.43 ppb |
| 2016-10-11 | 6100288-14 | 0.779 ppb |
| 2016-10-11 | 6100288-15 | 0.858 ppb |
| 2017-01-18 | 7010444-04 | ND |
| 2017-01-18 | 7010444-07 | 2.41 ppb |
| 2017-01-18 | 7010444-05 | 0.692 ppb |
| 2017-01-18 | 7010444-03 | ND |
| 2017-01-18 | 7010444-02 | 3.59 ppb |
| 2017-01-18 | 7010444-06 | 1.18 ppb |
| 2017-01-18 | 7010444-01 | 0.813 ppb |
| 2017-01-18 | 7010444-10 | 1.37 ppb |
| 2017-01-18 | 7010444-11 | 1.37 ppb |
| 2017-01-18 | 7010444-12 | 1.15 ppb |
| 2017-01-18 | 7010444-14 | 1.02 ppb |
| 2017-01-18 | 7010444-13 | 0.968 ppb |
| 2017-01-18 | 7010444-08 | 2.49 ppb |
| 2017-01-18 | 7010444-09 | 1.17 ppb |
| 2017-01-18 | 7010444-15 | 0.651 ppb |
| 2017-01-18 | 7010444-16 | 0.990 ppb |
| 2017-01-24 | 7010573-01 | 0.610 ppb |
| 2017-04-18 | 7040506-04 | ND |
| 2017-04-18 | 7040506-06 | ND |
| 2017-04-18 | 7040506-05 | ND |
| 2017-04-20 | 7040580-05 | 0.641 ppb |
| 2017-04-20 | 7040580-01 | 2.66 ppb |
| 2017-04-20 | 7040580-10 | 1.16 ppb |
| 2017-04-20 | 7040580-03 | 1.23 ppb |
| 2017-04-20 | 7040580-02 | 4.47 ppb |
| 2017-04-20 | 7040580-04 | 1.12 ppb |
| 2017-04-20 | 7040580-07 | 1.84 ppb |
| 2017-04-20 | 7040580-08 | 1.15 ppb |
| 2017-04-20 | 7040580-06 | 2.25 ppb |
| 2017-04-20 | 7040580-09 | 0.718 ppb |
| 2017-05-10 | 7050367-02 | ND |
| 2017-05-10 | 7050367-01 | 0.776 ppb |
| 2017-05-17 | 7050640-03 | 1.82 ppb |
| 2017-07-05 | 7070048-06 | ND |
| 2017-07-05 | 7070048-10 | 0.901 ppb |
| 2017-07-05 | 7070048-07 | ND |
| 2017-07-05 | 7070048-04 | 0.579 ppb |
| 2017-07-05 | 7070048-03 | 3.39 ppb |
| 2017-07-05 | 7070025-01 | ND |
| 2017-07-05 | 7070048-08 | 0.510 ppb |
| 2017-07-05 | 7070048-01 | 1.25 ppb |
| 2017-07-05 | 7070048-05 | ND |
| 2017-07-05 | 7070048-02 | ND |
| 2017-07-05 | 7070048-09 | ND |
| 2017-07-05 | 7070048-12 | ND |
| 2017-07-05 | 7070048-11 | 1.72 ppb |
| 2017-07-05 | 7070048-15 | ND |
| 2017-07-05 | 7070048-14 | ND |
| 2017-07-05 | 7070048-13 | 0.963 ppb |
| 2017-10-03 | 7100035-07 | ND |
| 2017-10-03 | 7100035-06 | 0.700 ppb |
| 2017-10-03 | 7100035-08 | ND |
| 2017-10-03 | 7100035-12 | 1.82 ppb |
| 2017-10-03 | 7100035-09 | ND |
| 2017-10-03 | 7100035-04 | 0.923 ppb |
| 2017-10-03 | 7100035-03 | 4.27 ppb |
| 2017-10-03 | 7100035-10 | 1.07 ppb |
| 2017-10-03 | 7100035-01 | 1.08 ppb |
| 2017-10-03 | 7100035-05 | 0.858 ppb |
| 2017-10-03 | 7100035-02 | ND |
| 2017-10-03 | 7100035-11 | 0.810 ppb |
| 2017-10-03 | 7100035-14 | 0.967 ppb |
| 2017-10-03 | 7100035-13 | 2.61 ppb |
| 2017-10-03 | 7100035-15 | 0.718 ppb |
| 2018-01-03 | 8010030-05 | 2.09 ppb |
| 2018-01-03 | 8010030-04 | ND |
| 2018-01-03 | 8010030-03 | 0.865 ppb |
| 2018-01-03 | 8010030-02 | 3.27 ppb |
| 2018-01-03 | 8010030-01 | ND |
| 2018-01-03 | 8010030-06 | 1.26 ppb |
| 2018-01-03 | 8010030-07 | 1.47 ppb |
| 2018-01-03 | 8010030-08 | 0.986 ppb |
| 2018-01-09 | 8010168-03 | 0.711 ppb |
| 2018-01-09 | 8010168-04 | 1.19 ppb |
| 2018-01-09 | 8010168-01 | 0.797 ppb |
| 2018-01-09 | 8010168-02 | 0.924 ppb |
| 2018-01-09 | 8010168-05 | 0.960 ppb |
| 2018-01-09 | 8010168-06 | 2.77 ppb |
| 2018-02-05 | 8020087-03 | 1.17 ppb |
| 2018-04-03 | 8040027-06 | ND |
| 2018-04-03 | 8040027-01 | 2.08 ppb |
| 2018-04-03 | 8040027-07 | ND |
| 2018-04-03 | 8040027-04 | 1.29 ppb |
| 2018-04-03 | 8040027-03 | 5.06 ppb |
| 2018-04-03 | 8040027-08 | 0.701 ppb |
| 2018-04-03 | 8040027-05 | ND |
| 2018-04-03 | 8040027-02 | ND |
| 2018-04-03 | 8040027-09 | 0.624 ppb |
| 2018-04-03 | 8040027-11 | 1.27 ppb |
| 2018-04-03 | 8040027-10 | 1.95 ppb |
| 2018-04-04 | 8040074-03 | 0.812 ppb |
| 2018-04-04 | 8040074-05 | 1.15 ppb |
| 2018-04-19 | 8040672-01 | 4.02 ppb |
| 2018-04-26 | 8040945-02 | 1.59 ppb |
| 2018-04-26 | 8040945-01 | 1.07 ppb |
| 2018-07-02 | 8070013-07 | ND |
| 2018-07-02 | 8070013-11 | 2.37 ppb |
| 2018-07-02 | 8070013-08 | ND |
| 2018-07-02 | 8070013-05 | 1.32 ppb |
| 2018-07-02 | 8070013-04 | 5.13 ppb |
| 2018-07-02 | 8070013-01 | 0.591 ppb |
| 2018-07-02 | 8070013-09 | 0.776 ppb |
| 2018-07-02 | 8070013-02 | 1.67 ppb |
| 2018-07-02 | 8070013-06 | 0.751 ppb |
| 2018-07-02 | 8070013-03 | 0.617 ppb |
| 2018-07-02 | 8070013-10 | 0.559 ppb |
| 2018-07-02 | 8070013-13 | 1.42 ppb |
| 2018-07-02 | 8070013-14 | 0.882 ppb |
| 2018-07-02 | 8070013-12 | 2.32 ppb |
| 2018-07-02 | 8070013-16 | 0.504 ppb |
| 2018-07-02 | 8070013-15 | 0.890 ppb |
| 2018-07-11 | 8070425-01 | 1.82 ppb |
| 2018-10-02 | 8100082-08 | 0.778 ppb |
| 2018-10-02 | 8100082-07 | 1.01 ppb |
| 2018-10-02 | 8100082-09 | ND |
| 2018-10-02 | 8100082-01 | 3.23 ppb |
| 2018-10-02 | 8100082-05 | 2.07 ppb |
| 2018-10-02 | 8100082-04 | 6.73 ppb |
| 2018-10-02 | 8100082-02 | 2.37 ppb |
| 2018-10-02 | 8100082-06 | 1.19 ppb |
| 2018-10-02 | 8100082-03 | 2.03 ppb |
| 2018-10-03 | 8100136-01 | ND |
| 2018-10-03 | 8100136-02 | 0.774 ppb |
| 2018-10-03 | 8100136-03 | 0.709 ppb |
| 2018-10-03 | 8100136-05 | 1.60 ppb |
| 2018-10-03 | 8100136-06 | 0.801 ppb |
| 2018-10-03 | 8100136-04 | 2.49 ppb |
| 2018-10-03 | 8100136-07 | 0.749 ppb |
| 2018-10-15 | 8100635-01 | 2.23 ppb |
| 2019-01-10 | 9010342-02 | ND |
| 2019-01-10 | 9010342-06 | 3.15 ppb |
| 2019-01-10 | 9010342-03 | 0.589 ppb |
| 2019-01-10 | 9010342-01 | 1.46 ppb |
| 2019-01-10 | 9010342-09 | 3.08 ppb |
| 2019-01-10 | 9010342-04 | 0.979 ppb |
| 2019-01-10 | 9010342-08 | 0.593 ppb |
| 2019-01-10 | 9010342-05 | 0.974 ppb |
| 2019-01-10 | 9010342-15 | 2.12 ppb |
| 2019-01-10 | 9010342-14 | 2.17 ppb |
| 2019-01-10 | 9010342-13 | 1.59 ppb |
| 2019-01-10 | 9010342-11 | 1.50 ppb |
| 2019-01-10 | 9010342-12 | 1.86 ppb |
| 2019-01-10 | 9010342-07 | 3.19 ppb |
| 2019-01-10 | 9010342-16 | 1.63 ppb |
| 2019-01-10 | 9010342-10 | 1.54 ppb |
| 2019-04-10 | 9040481-02 | ND |
| 2019-04-10 | 9040481-06 | 2.48 ppb |
| 2019-04-10 | 9040481-12 | 0.635 ppb |
| 2019-04-10 | 9040481-07 | 0.614 ppb |
| 2019-04-10 | 9040481-11 | 3.95 ppb |
| 2019-04-10 | 9040481-10 | ND |
| 2019-04-10 | 9040481-09 | ND |
| 2019-04-10 | 9040481-01 | 0.677 ppb |
| 2019-04-10 | 9040481-03 | 1.64 ppb |
| 2019-04-10 | 9040481-08 | 0.937 ppb |
| 2019-04-10 | 9040481-05 | 2.65 ppb |
| 2019-04-10 | 9040481-04 | 0.689 ppb |
| 2019-07-24 | 9071191-08 | 0.506 ppb |
| 2019-07-24 | 9071191-14 | 2.60 ppb |
| 2019-07-24 | 9071191-02 | 0.821 ppb |
| 2019-07-24 | 9071191-01 | 1.44 ppb |
| 2019-07-24 | 9071191-05 | 0.824 ppb |
| 2019-07-24 | 9071191-09 | 1.79 ppb |
| 2019-07-24 | 9071191-11 | 0.735 ppb |
| 2019-07-24 | 9071191-07 | 0.780 ppb |
| 2019-07-24 | 9071191-06 | 1.13 ppb |
| 2019-07-24 | 9071191-10 | 1.91 ppb |
| 2019-07-24 | 9071191-03 | 1.09 ppb |
| 2019-07-24 | 9071191-13 | 2.94 ppb |
| 2019-07-24 | 9071191-12 | 0.962 ppb |
| 2019-07-24 | 9071191-04 | 1.26 ppb |
| 2019-09-19 | 9090882-01 | 3.19 ppb |
| 2019-10-09 | 9100466-06 | 0.827 ppb |
| 2019-10-09 | 9100466-07 | 0.726 ppb |
| 2019-10-09 | 9100466-13 | 2.10 ppb |
| 2019-10-09 | 9100466-03 | 0.773 ppb |
| 2019-10-09 | 9100466-01 | 1.41 ppb |
| 2019-10-09 | 9100466-11 | 1.70 ppb |
| 2019-10-09 | 9100466-09 | 0.836 ppb |
| 2019-10-09 | 9100466-05 | 0.796 ppb |
| 2019-10-09 | 9100466-08 | 1.85 ppb |
| 2019-10-09 | 9100466-04 | 1.05 ppb |
| 2019-10-09 | 9100466-12 | 2.03 ppb |
| 2019-10-09 | 9100466-10 | 0.822 ppb |
| 2019-10-09 | 9100466-02 | 0.863 ppb |
| 2019-12-04 | 9120094-01 | 2.32 ppb |