Know Your Environment. Protect Your Health.

Nitrate and nitrite

Tri-water System

Nitrate and nitrite enter water from fertilizer runoff, septic tanks and urban runoff. These contaminants can cause oxygen deprivation for infants and increase the risk of cancer. Nitrite is significantly more toxic than nitrate. Click here to read more about nitrate.

 

32

Samples

0

Samples exceeding legal limit (MCL)

3

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018ND80ND
2019ND80ND
20200.0295 ppm43ND - 0.0410 ppm
20210.150 ppm43ND - 0.200 ppm
2022ND40ND
2023ND40ND

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

ppm = parts per million

All test results

Date Lab ID Result
2018-05-0235390243004ND
2018-05-0235390243003ND
2018-05-0235390243001ND
2018-05-0235390243002ND
2018-05-0235390243003ND
2018-05-0235390243004ND
2018-05-0235390243002ND
2018-05-0235390243001ND
2019-12-0635519669002ND
2019-12-0635519669001ND
2019-12-0635519669004ND
2019-12-0635519669003ND
2019-12-0635519669002ND
2019-12-0635519669001ND
2019-12-0635519669004ND
2019-12-0635519669003ND
2020-10-20355881140010.0410 ppm
2020-10-20355881140040.0370 ppm
2020-10-2035588114003ND
2020-10-20355881140020.0400 ppm
2021-06-15B2102722-0050.200 ppm
2021-06-15B2102722-0060.200 ppm
2021-06-15B2102722-0070.200 ppm
2021-06-15B2102722-008ND
2022-04-18B2201828-001ND
2022-04-18B2201828-002ND
2022-04-18B2201828-003ND
2022-04-18B2201828-004ND
2023-05-18B2302146-001ND
2023-05-18B2302146-002ND
2023-05-18B2302146-003ND
2023-05-18B2302146-004ND