EWG's Tap Water Database — 2021 UPDATE



North Channel Water Authority

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 exceeding legal limit (MCL)


Samples exceeding
health guidelines

Testing results - average by year

YearAverage resultSamples takenDetectionsRange of results
20140.550 ppm110.550 ppm
20150.870 ppm110.870 ppm
20160.110 ppm110.110 ppm
20170.150 ppm110.150 ppm
20180.490 ppm110.490 ppm
20190.380 ppm110.380 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
2014-05-22AC549960.550 ppm
2015-05-27AC933430.870 ppm
2016-07-15AD444120.110 ppm
2017-05-19AD849770.150 ppm
2018-10-25AE445240.490 ppm
2019-06-17AE707670.380 ppm