Nitrate
Concord 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 |
|---|---|---|---|---|
| 2014 | 1.02 ppm | 7 | 7 | 0.0570 ppm - 2.30 ppm |
| 2015 | 1.02 ppm | 7 | 7 | 0.0670 ppm - 2.20 ppm |
| 2016 | 0.583 ppm | 12 | 10 | ND - 2.20 ppm |
| 2017 | 1.04 ppm | 7 | 7 | 0.0636 ppm - 2.38 ppm |
| 2018 | 1.03 ppm | 8 | 7 | ND - 2.65 ppm |
| 2019 | 1.11 ppm | 7 | 7 | 0.0638 ppm - 2.35 ppm |
ppm = parts per million
State and national drinking water standards and health guidelines
EWG Health Guideline 0.14 ppm
The EWG Health Guideline of 0.14 ppm for nitrate was defined by EWG . This health guideline protects against cancer and harm to fetal growth and development.
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 |
|---|---|
| 2014-01-08 | 0.240 ppm |
| 2014-01-16 | 1.40 ppm |
| 2014-01-16 | 0.150 ppm |
| 2014-01-16 | 0.880 ppm |
| 2014-01-16 | 2.30 ppm |
| 2014-01-23 | 2.10 ppm |
| 2014-07-01 | 0.0570 ppm |
| 2015-01-16 | 2.20 ppm |
| 2015-01-16 | 0.240 ppm |
| 2015-01-16 | 0.120 ppm |
| 2015-02-06 | 1.10 ppm |
| 2015-02-24 | 1.90 ppm |
| 2015-02-24 | 1.50 ppm |
| 2015-07-01 | 0.0670 ppm |
| 2016-01-07 | 1.30 ppm |
| 2016-01-07 | 2.20 ppm |
| 2016-01-13 | 0.0600 ppm |
| 2016-02-04 | 1.80 ppm |
| 2016-02-16 | 0.930 ppm |
| 2016-02-17 | 0.0910 ppm |
| 2016-02-18 | 0.140 ppm |
| 2016-04-13 | 0.130 ppm |
| 2016-04-21 | 0.250 ppm |
| 2016-07-13 | ND |
| 2016-07-22 | 0.0940 ppm |
| 2016-11-16 | ND |
| 2017-01-19 | 0.980 ppm |
| 2017-01-19 | 1.90 ppm |
| 2017-01-19 | 0.280 ppm |
| 2017-01-19 | 1.50 ppm |
| 2017-03-13 | 2.38 ppm |
| 2017-03-23 | 0.142 ppm |
| 2017-07-06 | 0.0636 ppm |
| 2018-01-29 | 1.96 ppm |
| 2018-01-29 | 0.0992 ppm |
| 2018-01-29 | 0.180 ppm |
| 2018-01-29 | 2.65 ppm |
| 2018-03-15 | 0.911 ppm |
| 2018-03-22 | 2.40 ppm |
| 2018-07-02 | 0.0750 ppm |
| 2018-10-10 | ND |
| 2019-01-07 | 2.03 ppm |
| 2019-01-15 | 2.35 ppm |
| 2019-01-15 | 2.09 ppm |
| 2019-01-30 | 0.318 ppm |
| 2019-02-06 | 0.822 ppm |
| 2019-03-12 | 0.125 ppm |
| 2019-08-14 | 0.0638 ppm |