Know Your Environment. Protect Your Health.

Nitrate

Madera Valley Water Supply Corporation

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.

 

18

Samples

0

Samples exceeding legal limit (MCL)

11

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20181.05 ppm330.0790 ppm - 1.95 ppm
20191.14 ppm330.0879 ppm - 2.28 ppm
20200.940 ppm330.0784 ppm - 2.63 ppm
20211.24 ppm330.0924 ppm - 3.46 ppm
20221.42 ppm330.0851 ppm - 3.78 ppm
20231.75 ppm330.0785 ppm - 4.48 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
2018-07-18Q18289580190.0790 ppm
2018-07-18Q18289580201.95 ppm
2018-07-18Q18289580181.13 ppm
2019-06-20Q19382910011.06 ppm
2019-06-20Q19382910020.0879 ppm
2019-06-20Q19382910032.28 ppm
2020-08-17Q20332150100.111 ppm
2020-08-17Q20332150110.0784 ppm
2020-08-17Q20332150122.63 ppm
2021-03-03Q21055790050.0924 ppm
2021-03-03Q21055790160.154 ppm
2021-09-13Q21251000063.46 ppm
2022-02-07Q22043920070.399 ppm
2022-02-07Q22043920080.0851 ppm
2022-08-31Q22258140023.78 ppm
2023-04-20Q23148870070.679 ppm
2023-04-20Q23148870080.0785 ppm
2023-08-30Q23375530044.48 ppm