Nitrate
Westside Rural Water Supply Corporation
Nitrate, a fertilizer chemical, frequently contaminates drinking water due to agricultural and urban runoff, and discharges from municipal wastewater treatment plants and septic tanks. Excessive nitrate in water can cause oxygen deprivation in infants and increase the risk of cancer. Click here to read more about nitrate.
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 | 0.0547 ppm | 4 | 3 | ND - 0.121 ppm |
| 2019 | 0.0560 ppm | 4 | 3 | ND - 0.101 ppm |
| 2020 | 0.0654 ppm | 4 | 4 | 0.0375 ppm - 0.0905 ppm |
| 2021 | 0.0997 ppm | 4 | 4 | 0.0284 ppm - 0.204 ppm |
| 2022 | 0.0470 ppm | 4 | 3 | ND - 0.102 ppm |
| 2023 | 0.0223 ppm | 4 | 1 | ND - 0.0890 ppm |
ppm = parts per million
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 0.14 ppm
The EWG health guideline of 0.14 parts per million, or ppm, for nitrate and nitrite is based on the equivalent health guideline for nitrate, as defined in a peer-reviewed scientific study by EWG. This guideline represents a one-in-one-million annual cancer risk level.
EPA Maximum Contaminant
Level (MCL): 10 ppm
The legal limit for nitrate, established in 1962, was developed to protect infants from acute methemoglobinemia, a life-threatening disorder of oxygen transport in the body. This limit does not fully protect against the risk of cancer and harm to the developing fetus.
ppm = parts per million
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-10-30 | Q1843596012 | ND |
| 2018-10-30 | Q1843596013 | 0.0500 ppm |
| 2018-10-30 | Q1843596023 | 0.121 ppm |
| 2018-10-30 | Q1843596011 | 0.0477 ppm |
| 2019-05-07 | Q1920849015 | 0.101 ppm |
| 2019-05-07 | Q1920849018 | 0.0796 ppm |
| 2019-05-07 | Q1920849019 | ND |
| 2019-05-07 | Q1920849020 | 0.0435 ppm |
| 2020-01-23 | Q2002763018 | 0.0800 ppm |
| 2020-01-23 | Q2002763019 | 0.0905 ppm |
| 2020-01-23 | Q2002763020 | 0.0535 ppm |
| 2020-01-23 | Q2002763021 | 0.0375 ppm |
| 2021-01-25 | Q2101699018 | 0.117 ppm |
| 2021-01-25 | Q2101699026 | 0.204 ppm |
| 2021-01-25 | Q2101699020 | 0.0493 ppm |
| 2021-01-25 | Q2101699019 | 0.0284 ppm |
| 2022-11-10 | Q2233973001 | 0.102 ppm |
| 2022-11-10 | Q2233973017 | 0.0246 ppm |
| 2022-11-10 | Q2233973018 | ND |
| 2022-11-10 | Q2233973019 | 0.0613 ppm |
| 2023-03-20 | Q2310439008 | 0.0890 ppm |
| 2023-06-21 | Q2323858010 | ND |
| 2023-06-21 | Q2323858011 | ND |
| 2023-06-21 | Q2323858012 | ND |