Know Your Environment. Protect Your Health.

Nitrate

Mill River Water District

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.

 

8

Samples

0

Samples exceeding legal limit (MCL)

4

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.0900 ppm110.0900 ppm
20190.199 ppm220.0810 ppm - 0.317 ppm
20200.106 ppm220.0550 ppm - 0.156 ppm
20210.269 ppm220.158 ppm - 0.380 ppm
20220.173 ppm220.110 ppm - 0.235 ppm
20230.0912 ppm220.0633 ppm - 0.119 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
2020-06-17AW11407-NIT0.0550 ppm
2020-12-09AW23564-NIT0.156 ppm
2021-05-19AX09623-NIT0.158 ppm
2021-12-09AX24400-NIT0.380 ppm
2022-06-08AY09687-NIT0.235 ppm
2022-11-02AY19818-NIT0.110 ppm
2023-05-22AZ09224-NIT0.119 ppm
2023-10-17AZ19164-NIT0.0633 ppm