Know Your Environment. Protect Your Health.

Nitrate

Harris County Water Control and Improvement District 114

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)

9

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.137 ppm330.0200 ppm - 0.260 ppm
20190.297 ppm32ND - 0.690 ppm
20200.273 ppm32ND - 0.550 ppm
20210.143 ppm32ND - 0.240 ppm
20220.157 ppm32ND - 0.400 ppm
20230.230 ppm31ND - 0.690 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
2018-04-03AE209310.130 ppm
2018-04-03AE209290.0200 ppm
2018-07-09AE325290.260 ppm
2019-05-08AE653020.690 ppm
2019-05-08AE65304ND
2019-05-08AE653050.200 ppm
2020-01-27AE952110.270 ppm
2020-04-23AF079230.550 ppm
2020-04-23AF07924ND
2021-02-01AF417450.240 ppm
2021-04-15AF502340.190 ppm
2021-04-15AF50236ND
2022-02-10AF841040.0700 ppm
2022-04-20AF938010.400 ppm
2022-04-20AF93802ND
2023-01-31AG266290.690 ppm
2023-06-06AG43153ND
2023-06-06AG43158ND