Know Your Environment. Protect Your Health.

Nitrate

Gonzales County 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.

 

60

Samples

0

Samples exceeding legal limit (MCL)

17

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.446 ppm105ND - 2.04 ppm
20190.392 ppm103ND - 1.46 ppm
20200.295 ppm103ND - 1.76 ppm
20210.0340 ppm101ND - 0.340 ppm
20220.227 ppm104ND - 1.27 ppm
20230.304 ppm104ND - 1.21 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
2018-02-08AE12914ND
2018-02-08AE128982.04 ppm
2018-03-12AE17722ND
2018-03-12AE177230.01000 ppm
2018-03-12AE17724ND
2018-03-12AE177260.0200 ppm
2018-05-03AE249231.75 ppm
2018-08-16AE372650.640 ppm
2018-12-12AE48552ND
2018-12-12AE48584ND
2019-01-09AE49124ND
2019-01-09AE49125ND
2019-01-09AE49126ND
2019-01-09AE491271.13 ppm
2019-01-09AE49142ND
2019-01-09AE49143ND
2019-03-05AE57072ND
2019-04-02AE607811.46 ppm
2019-07-12AE742801.33 ppm
2019-10-14AE86406ND
2020-01-21AE941841.76 ppm
2020-01-21AE94186ND
2020-01-21AE94219ND
2020-01-21AE94220ND
2020-03-10AF01876ND
2020-03-10AF01881ND
2020-03-10AF01911ND
2020-04-13AF064230.550 ppm
2020-08-24AF247650.640 ppm
2020-11-13AF34782ND
2021-01-13AF39008ND
2021-01-13AF39022ND
2021-01-13AF39009ND
2021-01-13AF39010ND
2021-04-01AF48756ND
2021-04-01AF48757ND
2021-04-01AF48758ND
2021-08-18AF667910.340 ppm
2021-08-18AF66792ND
2021-10-05AF72213ND
2022-02-09AF838670.240 ppm
2022-02-09AF83868ND
2022-02-09AF83900ND
2022-04-20AF93798ND
2022-04-20AF937990.670 ppm
2022-04-20AF93815ND
2022-09-30AG155910.0900 ppm
2022-09-30AG15609ND
2022-09-30AG15592ND
2022-12-28AG229151.27 ppm
2023-03-15AG331171.21 ppm
2023-03-15AG33134ND
2023-03-15AG33138ND
2023-03-29AG34735ND
2023-06-21AG451390.580 ppm
2023-06-21AG45140ND
2023-06-21AG45141ND
2023-06-21AG45142ND
2023-09-11AG554000.180 ppm
2023-11-28AG644931.07 ppm