Nitrate
New 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 | 0.0917 ppm | 4 | 4 | 0.0209 ppm - 0.261 ppm |
| 2019 | 0.0338 ppm | 4 | 4 | 0.0199 ppm - 0.0430 ppm |
| 2020 | 0.0412 ppm | 4 | 4 | 0.0215 ppm - 0.0570 ppm |
| 2021 | 0.0391 ppm | 4 | 4 | 0.0314 ppm - 0.0510 ppm |
| 2022 | 0.0787 ppm | 4 | 4 | 0.0267 ppm - 0.161 ppm |
| 2023 | 0.0351 ppm | 4 | 4 | 0.0151 ppm - 0.0494 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 |
|---|---|---|
| 2018-06-06 | Q1822507014 | 0.0209 ppm |
| 2018-06-06 | Q1822507015 | 0.0384 ppm |
| 2018-06-06 | Q1822507013 | 0.261 ppm |
| 2018-09-19 | Q1837597001 | 0.0463 ppm |
| 2019-06-03 | Q1930848001 | 0.0367 ppm |
| 2019-06-03 | Q1930848002 | 0.0430 ppm |
| 2019-09-23 | Q1968123003 | 0.0354 ppm |
| 2019-12-10 | Q1979549003 | 0.0199 ppm |
| 2020-11-09 | Q2043745019 | 0.0345 ppm |
| 2020-11-09 | Q2043745021 | 0.0215 ppm |
| 2020-11-09 | Q2043745022 | 0.0519 ppm |
| 2020-11-09 | Q2043745023 | 0.0570 ppm |
| 2021-04-15 | Q2109763020 | 0.0314 ppm |
| 2021-04-15 | Q2109763029 | 0.0340 ppm |
| 2021-04-15 | Q2109763022 | 0.0510 ppm |
| 2021-04-15 | Q2109763021 | 0.0399 ppm |
| 2022-05-09 | Q2213779003 | 0.0896 ppm |
| 2022-05-09 | Q2213779008 | 0.161 ppm |
| 2022-05-09 | Q2213779013 | 0.0267 ppm |
| 2022-05-09 | Q2213779014 | 0.0373 ppm |
| 2023-06-15 | Q2322767013 | 0.0323 ppm |
| 2023-06-15 | Q2322767024 | 0.0494 ppm |
| 2023-06-15 | Q2322767025 | 0.0151 ppm |
| 2023-06-15 | Q2322767026 | 0.0436 ppm |