Nitrate and nitrite
Laurel Pump District
Nitrate and nitrite enter water from fertilizer runoff, septic tanks and urban runoff. These contaminants can cause oxygen deprivation for infants and increase the risk of cancer. Nitrite is significantly more toxic than nitrate. 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 | 0.729 ppm | 13 | 13 | 0.286 ppm - 1.92 ppm |
| 2019 | 0.416 ppm | 13 | 11 | ND - 0.905 ppm |
| 2020 | 0.663 ppm | 12 | 11 | ND - 1.60 ppm |
| 2021 | 0.950 ppm | 13 | 11 | ND - 2.65 ppm |
| 2022 | 1.18 ppm | 13 | 12 | ND - 3.48 ppm |
| 2023 | 0.852 ppm | 13 | 13 | 0.530 ppm - 1.72 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
ppm = parts per million
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-01-24 | S757463 | 0.300 ppm |
| 2018-02-14 | S757771 | 0.400 ppm |
| 2018-03-13 | S757791 | 0.700 ppm |
| 2018-04-05 | S759344 | 0.864 ppm |
| 2018-04-06 | S770742 | 0.882 ppm |
| 2018-05-24 | S759352 | 0.286 ppm |
| 2018-06-05 | S759474 | 1.92 ppm |
| 2018-07-12 | S757801 | 0.644 ppm |
| 2018-08-30 | S759544 | 1.82 ppm |
| 2018-09-19 | S759570 | 0.530 ppm |
| 2018-10-16 | S759591 | 0.386 ppm |
| 2018-11-14 | S757813 | 0.413 ppm |
| 2018-12-13 | S759672 | 0.340 ppm |
| 2019-01-10 | S759676 | 0.644 ppm |
| 2019-02-21 | S759643 | 0.905 ppm |
| 2019-03-12 | S759633 | 0.489 ppm |
| 2019-03-22 | S817053 | 0.665 ppm |
| 2019-04-02 | S759636 | 0.533 ppm |
| 2019-05-23 | S759282 | 0.332 ppm |
| 2019-06-20 | S759290 | ND |
| 2019-07-24 | S759728 | 0.648 ppm |
| 2019-08-21 | S759703 | 0.386 ppm |
| 2019-09-03 | S759704 | 0.262 ppm |
| 2019-10-18 | S895865 | 0.285 ppm |
| 2019-11-12 | S759358 | ND |
| 2019-12-09 | S919987 | 0.260 ppm |
| 2020-01-09 | S759366 | 0.270 ppm |
| 2020-02-12 | S922978 | ND |
| 2020-03-13 | S922986 | 0.481 ppm |
| 2020-03-25 | S901906 | 0.394 ppm |
| 2020-05-20 | S923023 | 1.10 ppm |
| 2020-06-23 | S923045 | 1.27 ppm |
| 2020-07-14 | S923031 | 1.60 ppm |
| 2020-08-13 | S923038 | 0.646 ppm |
| 2020-09-23 | S992027 | 0.455 ppm |
| 2020-10-08 | S992051 | 0.393 ppm |
| 2020-11-18 | S1020766 | 1.25 ppm |
| 2020-12-10 | S992059 | 0.0931 ppm |
| 2021-01-14 | S992067 | 0.952 ppm |
| 2021-02-08 | S1035156 | 2.16 ppm |
| 2021-02-12 | S1035165 | 1.42 ppm |
| 2021-03-04 | S992075 | 2.65 ppm |
| 2021-04-12 | S923105 | 0.656 ppm |
| 2021-05-06 | S923076 | 0.614 ppm |
| 2021-06-04 | S923085 | 0.666 ppm |
| 2021-07-02 | S923155 | ND |
| 2021-08-05 | S923122 | 0.404 ppm |
| 2021-09-03 | S923180 | 1.56 ppm |
| 2021-10-08 | S923203 | 0.931 ppm |
| 2021-11-19 | S1073506 | 0.333 ppm |
| 2021-12-03 | S1073512 | ND |
| 2022-01-06 | S923191 | 3.03 ppm |
| 2022-01-14 | S1136787 | 0.357 ppm |
| 2022-02-16 | S1073792 | ND |
| 2022-03-03 | S1073808 | 0.981 ppm |
| 2022-04-14 | S1073519 | 0.761 ppm |
| 2022-05-13 | S1073571 | 3.48 ppm |
| 2022-06-03 | S1073572 | 0.546 ppm |
| 2022-07-01 | S1073550 | 0.411 ppm |
| 2022-08-22 | S923170 | 0.770 ppm |
| 2022-09-12 | S1223017 | 0.621 ppm |
| 2022-10-05 | S1223023 | 2.79 ppm |
| 2022-11-07 | S1073542 | 0.519 ppm |
| 2022-12-06 | S1073558 | 1.05 ppm |
| 2023-01-05 | S1223044 | 0.553 ppm |
| 2023-02-15 | S1223058 | 0.667 ppm |
| 2023-02-24 | S1257106 | 0.545 ppm |
| 2023-03-13 | S1223092 | 0.536 ppm |
| 2023-04-10 | S1223062 | 1.72 ppm |
| 2023-05-26 | S1223080 | 0.530 ppm |
| 2023-06-15 | S1223087 | 0.663 ppm |
| 2023-07-07 | S1223100 | 0.901 ppm |
| 2023-08-04 | S1073891 | 0.646 ppm |
| 2023-09-18 | S1223148 | 1.13 ppm |
| 2023-10-23 | S1223152 | 0.786 ppm |
| 2023-11-03 | S1073897 | 0.720 ppm |
| 2023-12-08 | S1073854 | 1.68 ppm |