Nitrate
Mountain Springs 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 | 0.0354 ppm | 4 | 4 | 0.0165 ppm - 0.0597 ppm |
| 2019 | 0.0190 ppm | 4 | 3 | ND - 0.0329 ppm |
| 2020 | 0.0200 ppm | 4 | 3 | ND - 0.0321 ppm |
| 2021 | 0.0147 ppm | 4 | 3 | ND - 0.0338 ppm |
| 2022 | 0.0320 ppm | 4 | 4 | 0.0151 ppm - 0.0475 ppm |
| 2023 | 0.0244 ppm | 4 | 4 | 0.0160 ppm - 0.0335 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 |
|---|---|---|
| 2018-03-13 | Q1810191008 | 0.0165 ppm |
| 2018-03-13 | Q1810191009 | 0.0597 ppm |
| 2018-03-13 | Q1810191007 | 0.0398 ppm |
| 2018-06-28 | Q1826059003 | 0.0257 ppm |
| 2019-01-28 | Q1904051001 | 0.0221 ppm |
| 2019-01-28 | Q1904051002 | ND |
| 2019-01-28 | Q1904051003 | 0.0329 ppm |
| 2019-01-28 | Q1904051004 | 0.0210 ppm |
| 2020-05-13 | Q2019339003 | 0.0318 ppm |
| 2020-11-05 | Q2043235018 | 0.0162 ppm |
| 2020-11-05 | Q2043235024 | 0.0321 ppm |
| 2020-11-05 | Q2043235025 | ND |
| 2021-11-16 | Q2132004009 | 0.0103 ppm |
| 2021-11-16 | Q2132004012 | ND |
| 2021-11-16 | Q2132004011 | 0.0148 ppm |
| 2021-11-16 | Q2132004010 | 0.0338 ppm |
| 2022-10-18 | Q2231735001 | 0.0475 ppm |
| 2022-10-18 | Q2231735006 | 0.0329 ppm |
| 2022-10-18 | Q2231735007 | 0.0151 ppm |
| 2022-12-06 | Q2236331001 | 0.0324 ppm |
| 2023-11-30 | Q2351033013 | 0.0164 ppm |
| 2023-11-30 | Q2351033014 | 0.0317 ppm |
| 2023-11-30 | Q2351033015 | 0.0160 ppm |
| 2023-12-13 | Q2353413008 | 0.0335 ppm |