Nitrate and nitrite

Cucamonga Valley Water District

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
2013	N/A	0	0	N/A
2014	3.07 ppm	18	17	ND - 16.0 ppm
2015	1.38 ppm	6	6	0.430 ppm - 2.70 ppm
2016	1.54 ppm	5	3	ND - 5.20 ppm
2017	2.51 ppm	16	14	ND - 7.20 ppm
2018	1.87 ppm	21	19	ND - 7.80 ppm
2019	0.300 ppm	4	1	ND - 1.20 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
2014-06-18	3761-051-1138	1.60 ppm
2014-06-19	3761-054-0940	3.00 ppm
2014-06-19	3761-053-0925	0.890 ppm
2014-06-19	3761-052-0930	2.20 ppm
2014-06-19	3761-050-1035	1.90 ppm
2014-06-26	3761-035-1022	16.0 ppm
2014-06-26	3761-035-1007	7.80 ppm
2014-06-26	3761-034-1042	5.50 ppm
2014-07-10	3761-004-1022	3.20 ppm
2014-07-10	3761-042-1015	2.70 ppm
2014-07-10	3761-003-1052	3.80 ppm
2014-07-10	3761-025-1042	1.20 ppm
2014-08-05	3761-055-1150	2.30 ppm
2014-08-14	3761-016-1105	0.710 ppm
2014-08-14	3761-022-0842	ND
2014-08-14	3761-001-0917	1.10 ppm
2014-08-21	3761-023-0930	0.610 ppm
2014-08-21	3761-024-0940	0.670 ppm
2015-05-13	3761-055-1050	2.30 ppm
2015-06-11	3761-022-1035	0.460 ppm
2015-06-11	3761-001-1020	0.990 ppm
2015-07-09	3761-017-1100	0.430 ppm
2015-08-20	3761-055-0925	1.40 ppm
2015-11-23	3761-055-0900	2.70 ppm
2016-02-11	3761-055-1040	1.50 ppm
2016-07-21	3761-001-0930	1.000 ppm
2016-07-21	3761-022-0955	ND
2016-07-21	3761-017-1120	ND
2016-11-23	3761-035-1440	5.20 ppm
2017-06-14	3761-035-0930	3.90 ppm
2017-06-15	3761-034-0910	7.20 ppm
2017-06-19	3761-042-0859	2.60 ppm
2017-06-19	3761-053-0908	5.40 ppm
2017-06-22	3761-025-0818	1.20 ppm
2017-06-22	3761-003-0806	2.70 ppm
2017-06-22	3761-053-0902	0.930 ppm
2017-06-22	3761-052-0913	2.40 ppm
2017-06-26	3761-054-1041	3.20 ppm
2017-06-28	3761-050-0744	1.80 ppm
2017-06-28	3761-051-0735	1.60 ppm
2017-07-03	3761-055-1041	2.60 ppm
2017-07-12	3761-017-1408	ND
2017-07-13	3761-001-0733	1.40 ppm
2017-07-13	3761-022-0928	ND
2017-07-17	3761-004-1231	3.20 ppm
2018-03-14	3761-016-1008	0.780 ppm
2018-03-14	3761-023-1149	0.480 ppm
2018-03-28	3761-024-0931	0.750 ppm
2018-06-20	9588-034-1200	7.80 ppm
2018-06-21	9588-003-0848	4.20 ppm
2018-06-21	9588-025-0832	1.60 ppm
2018-06-21	9588-050-1244	1.70 ppm
2018-06-21	9588-051-0815	1.60 ppm
2018-06-25	9588-035-1127	3.00 ppm
2018-06-25	9588-004-0941	3.60 ppm
2018-06-26	9588-053-1000	0.740 ppm
2018-06-26	9588-052-0925	3.50 ppm
2018-06-26	9588-054-1035	2.60 ppm
2018-06-27	9588-055-1140	2.50 ppm
2018-07-11	9588-042-0950	1.40 ppm
2018-07-12	9588-017-1214	ND
2018-07-18	9588-022-1010	ND
2018-07-18	9588-001-0950	1.10 ppm
2018-07-26	9588-016-0846	0.660 ppm
2018-07-26	9588-024-0904	0.600 ppm
2018-07-26	9588-023-0912	0.600 ppm
2019-07-01	9588-017-0945	ND
2019-07-24	9588-017-1115	ND
2019-07-26	9588-001-0900	1.20 ppm
2019-07-26	9588-022-0915	ND