Nitrate
Littleton Water Department
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 | 0.577 ppm | 13 | 13 | 0.0600 ppm - 1.10 ppm |
| 2019 | 0.753 ppm | 7 | 7 | 0.190 ppm - 1.20 ppm |
| 2020 | 0.623 ppm | 7 | 7 | 0.310 ppm - 0.990 ppm |
| 2021 | 0.724 ppm | 8 | 8 | 0.0500 ppm - 1.59 ppm |
| 2022 | 0.748 ppm | 8 | 8 | 0.1000 ppm - 1.37 ppm |
| 2023 | 0.734 ppm | 8 | 7 | ND - 1.33 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 | Result |
|---|---|
| 2018-04-11 | 0.480 ppm |
| 2018-04-26 | 0.300 ppm |
| 2018-04-26 | 1.10 ppm |
| 2018-04-26 | 0.830 ppm |
| 2018-04-29 | 0.0600 ppm |
| 2018-04-29 | 0.570 ppm |
| 2018-04-29 | 0.810 ppm |
| 2018-05-01 | 0.880 ppm |
| 2018-05-01 | 0.0700 ppm |
| 2018-05-01 | 0.590 ppm |
| 2018-05-07 | 0.680 ppm |
| 2018-05-07 | 0.440 ppm |
| 2018-06-19 | 0.690 ppm |
| 2019-05-01 | 1.20 ppm |
| 2019-05-01 | 0.830 ppm |
| 2019-05-01 | 0.920 ppm |
| 2019-05-01 | 0.190 ppm |
| 2019-05-30 | 0.480 ppm |
| 2019-06-05 | 1.10 ppm |
| 2019-06-17 | 0.550 ppm |
| 2020-05-14 | 0.640 ppm |
| 2020-05-14 | 0.990 ppm |
| 2020-05-26 | 0.310 ppm |
| 2020-05-26 | 0.640 ppm |
| 2020-05-26 | 0.510 ppm |
| 2020-05-26 | 0.560 ppm |
| 2020-06-16 | 0.710 ppm |
| 2021-04-05 | 0.500 ppm |
| 2021-04-05 | 0.700 ppm |
| 2021-04-05 | 0.0500 ppm |
| 2021-04-05 | 0.150 ppm |
| 2021-04-05 | 1.54 ppm |
| 2021-04-05 | 0.590 ppm |
| 2021-04-12 | 1.59 ppm |
| 2021-06-08 | 0.670 ppm |
| 2022-05-18 | 1.37 ppm |
| 2022-05-18 | 0.1000 ppm |
| 2022-05-18 | 0.750 ppm |
| 2022-05-18 | 1.04 ppm |
| 2022-05-18 | 0.390 ppm |
| 2022-05-18 | 0.480 ppm |
| 2022-05-18 | 0.870 ppm |
| 2022-05-18 | 0.980 ppm |
| 2023-06-16 | ND |
| 2023-06-16 | 0.790 ppm |
| 2023-06-16 | 0.860 ppm |
| 2023-06-16 | 1.07 ppm |
| 2023-06-16 | 0.660 ppm |
| 2023-06-16 | 1.33 ppm |
| 2023-06-16 | 0.230 ppm |
| 2023-06-16 | 0.930 ppm |