Know Your Environment. Protect Your Health.

Nitrate

North Peninsula

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.

 

31

Samples

0

Samples exceeding legal limit (MCL)

7

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.348 ppm62ND - 1.50 ppm
20190.317 ppm62ND - 1.32 ppm
2020N/A00N/A
20210.260 ppm61ND - 1.56 ppm
20220.193 ppm71ND - 1.35 ppm
20230.223 ppm61ND - 1.34 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
2018-05-15ND
2018-05-150.590 ppm
2018-05-151.50 ppm
2018-05-21ND
2018-05-21ND
2018-08-28ND
2019-04-241.32 ppm
2019-06-11ND
2019-06-11ND
2019-06-11ND
2019-06-110.580 ppm
2019-06-25ND
2021-05-184113539ND
2021-05-204118585ND
2021-05-2041243341.56 ppm
2021-06-224131444ND
2021-08-234163390ND
2021-08-234163391ND
2022-07-234308949ND
2022-08-154335422ND
2022-08-254335316ND
2022-08-254335317ND
2022-11-1443752121.35 ppm
2022-11-154390293ND
2022-11-154390294ND
2023-08-2445061621.34 ppm
2023-08-244506161ND
2023-08-244506163ND
2023-08-244506160ND
2023-08-284506171ND
2023-08-284506170ND