Nitrate
City of Post Falls
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 |
|---|---|---|---|---|
| 2013 | N/A | 0 | 0 | N/A |
| 2014 | 0.853 ppm | 13 | 13 | 0.0580 ppm - 1.34 ppm |
| 2015 | 0.812 ppm | 15 | 15 | 0.310 ppm - 1.09 ppm |
| 2016 | 0.796 ppm | 14 | 13 | ND - 1.11 ppm |
| 2017 | 0.771 ppm | 11 | 11 | 0.330 ppm - 1.45 ppm |
| 2018 | 0.986 ppm | 21 | 21 | 0.430 ppm - 1.39 ppm |
| 2019 | 0.968 ppm | 14 | 14 | 0.444 ppm - 1.45 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 | Lab ID | Result |
|---|---|---|
| 2014-01-27 | I012714129 | 0.514 ppm |
| 2014-01-27 | I012714105 | 1.14 ppm |
| 2014-01-27 | I1280147 | 1.12 ppm |
| 2014-03-21 | N149078 | 0.0580 ppm |
| 2014-06-02 | I060214129 | 0.804 ppm |
| 2014-06-02 | I060214105 | 1.34 ppm |
| 2014-06-02 | I060214103 | 0.288 ppm |
| 2014-06-02 | I060214104 | 1.32 ppm |
| 2014-09-04 | N154281 | 0.980 ppm |
| 2014-09-04 | N154279 | 0.800 ppm |
| 2014-09-04 | N154280 | 1.12 ppm |
| 2014-09-04 | N154282 | 0.770 ppm |
| 2014-09-04 | N154283 | 0.830 ppm |
| 2015-03-18 | I031815143 | 0.862 ppm |
| 2015-03-18 | I031815129 | 0.349 ppm |
| 2015-03-18 | I031815103 | 0.670 ppm |
| 2015-07-14 | I071415143 | 0.995 ppm |
| 2015-07-14 | I071415129 | 0.531 ppm |
| 2015-07-14 | I071415104 | 1.06 ppm |
| 2015-07-14 | I071415103 | 0.310 ppm |
| 2015-09-14 | N164589 | 0.730 ppm |
| 2015-09-14 | N164587 | 0.960 ppm |
| 2015-09-14 | N164588 | 1.09 ppm |
| 2015-09-14 | N164590 | 0.890 ppm |
| 2015-11-17 | I111715143 | 0.996 ppm |
| 2015-11-17 | I111715129 | 0.777 ppm |
| 2015-11-17 | I111715104 | 1.01 ppm |
| 2015-11-17 | I111715 | 0.945 ppm |
| 2016-03-22 | N032216143 | 0.918 ppm |
| 2016-03-22 | N032216104 | 1.11 ppm |
| 2016-03-22 | N032216103 | 1.000 ppm |
| 2016-07-19 | 071916129 | 0.452 ppm |
| 2016-07-19 | N071916103 | 0.407 ppm |
| 2016-07-19 | N071916104 | 0.886 ppm |
| 2016-07-19 | N071916143 | 0.835 ppm |
| 2016-12-13 | I178297 | 0.820 ppm |
| 2016-12-13 | N178300 | ND |
| 2016-12-13 | N178299 | 1.02 ppm |
| 2016-12-13 | N178298 | 0.970 ppm |
| 2016-12-14 | I178364 | 0.980 ppm |
| 2016-12-14 | I178363 | 1.03 ppm |
| 2016-12-14 | I178362 | 0.710 ppm |
| 2017-03-14 | I170314060003104 | 0.983 ppm |
| 2017-03-14 | I170314060004143 | 0.700 ppm |
| 2017-03-14 | I170314060002129 | 0.330 ppm |
| 2017-03-14 | I170314060001103 | 0.474 ppm |
| 2017-07-18 | I170418047004143 | 0.885 ppm |
| 2017-07-18 | I170418047003104 | 1.45 ppm |
| 2017-07-18 | I170418047002129 | 0.584 ppm |
| 2017-07-18 | I170418047001103 | 0.712 ppm |
| 2017-12-15 | N189377 | 1.10 ppm |
| 2017-12-15 | N189376 | 0.730 ppm |
| 2017-12-15 | N189375 | 0.530 ppm |
| 2018-03-13 | I180313043004 | 1.20 ppm |
| 2018-03-13 | I180313043002 | 1.14 ppm |
| 2018-03-13 | I180313043001 | 1.06 ppm |
| 2018-03-13 | I180313043003 | 1.13 ppm |
| 2018-07-17 | I180717054001 | 0.734 ppm |
| 2018-07-17 | I180717054003 | 1.13 ppm |
| 2018-07-17 | I180717054004 | 1.12 ppm |
| 2018-07-17 | I170717054003 | 1.13 ppm |
| 2018-07-17 | I180717054002 | 0.753 ppm |
| 2018-07-17 | 8180717054001 | 0.734 ppm |
| 2018-11-06 | I181106039003 | 1.04 ppm |
| 2018-11-06 | I181106039001 | 1.04 ppm |
| 2018-11-06 | I181106039002 | 0.638 ppm |
| 2018-11-06 | I181106039004 | 1.10 ppm |
| 2018-12-18 | N200287 | 0.640 ppm |
| 2018-12-18 | N200286 | 1.27 ppm |
| 2018-12-18 | N200285 | 0.650 ppm |
| 2018-12-18 | N200284 | 1.39 ppm |
| 2018-12-18 | N200283 | 0.430 ppm |
| 2018-12-19 | N200327 | 1.15 ppm |
| 2018-12-19 | N200326 | 1.23 ppm |
| 2019-03-12 | I190312040003 | 1.20 ppm |
| 2019-03-12 | I190312040002 | 1.01 ppm |
| 2019-03-12 | I190312040001 | 0.922 ppm |
| 2019-07-16 | I190716024004 | 1.12 ppm |
| 2019-07-16 | I190716024002 | 0.787 ppm |
| 2019-07-16 | I19071624001 | 0.444 ppm |
| 2019-07-16 | I190716024003 | 1.13 ppm |
| 2019-11-12 | I210891 | 1.09 ppm |
| 2019-11-13 | I210941 | 1.10 ppm |
| 2019-11-18 | I211062 | 0.648 ppm |
| 2019-11-18 | I211059 | 0.673 ppm |
| 2019-11-19 | I211103 | 0.802 ppm |
| 2019-12-09 | I211716 | 1.18 ppm |
| 2019-12-16 | I211917 | 1.45 ppm |