Nitrate and nitrite

Grand Prairie Bayou 2 PWA

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.

MORE ABOUT THIS CONTAMINANT

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2014	0.510 ppm	4	3	ND - 1.60 ppm
2015	0.973 ppm	3	3	0.230 ppm - 1.38 ppm
2016	0.995 ppm	2	2	0.660 ppm - 1.33 ppm
2017	0.783 ppm	3	3	0.300 ppm - 1.36 ppm
2018	0.760 ppm	5	5	0.250 ppm - 1.34 ppm
2019	0.480 ppm	2	2	0.480 ppm

ppm = parts per million

State and national drinking water standards and health guidelines

EWG Health Guideline 0.14 ppm

The 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
2014-02-06	140380002	0.200 ppm
2014-05-12	141360004	0.240 ppm
2014-05-12	141360003	1.60 ppm
2014-10-07	Y142820001	ND
2015-05-06	Y151270045	1.38 ppm
2015-05-06	Y151270040	0.230 ppm
2015-11-23	Y153280003	1.31 ppm
2016-05-09	Y161330016	1.33 ppm
2016-05-09	Y161330017	0.660 ppm
2017-01-10	Y170120023	0.300 ppm
2017-06-05	Y171590109	1.36 ppm
2017-06-05	Y171590110	0.690 ppm
2018-04-17	Y181090013	0.670 ppm
2018-05-22	Y181440020	1.34 ppm
2018-09-18	Y182630004	0.270 ppm
2018-09-18	Y182630006	0.250 ppm
2018-09-18	Y182630005	1.27 ppm
2019-04-15	Y191080012	0.480 ppm
2019-04-15	Y191080013	0.480 ppm