Know Your Environment. Protect Your Health.

Nitrate

Shady Grove 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.

 

12

Samples

0

Samples exceeding legal limit (MCL)

8

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.369 ppm220.334 ppm - 0.403 ppm
20190.266 ppm220.253 ppm - 0.278 ppm
20200.107 ppm220.103 ppm - 0.110 ppm
20210.320 ppm220.266 ppm - 0.373 ppm
20220.0600 ppm220.0500 ppm - 0.0700 ppm
20230.191 ppm220.162 ppm - 0.220 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
2018-05-10Q18193210020.403 ppm
2018-05-10Q18193210040.334 ppm
2019-11-26Q19782780010.278 ppm
2019-11-26Q19782780020.253 ppm
2020-08-04Q20303650010.110 ppm
2020-08-04Q20303650020.103 ppm
2021-11-03Q21308890010.373 ppm
2021-11-03Q21308890040.266 ppm
2022-02-18Q22062020010.0700 ppm
2022-02-18Q22062020020.0500 ppm
2023-11-01Q23468470030.220 ppm
2023-11-01Q23468470040.162 ppm