Nitrate
Castaic Lake Water Agency
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.
Testing results - average by year
Year | Average result | Samples taken | Detections | Range of results |
---|---|---|---|---|
2014 | 2.23 ppm | 43 | 41 | ND - 4.92 ppm |
2015 | 2.48 ppm | 43 | 42 | ND - 3.84 ppm |
2016 | 2.63 ppm | 48 | 46 | ND - 4.10 ppm |
2017 | 2.35 ppm | 51 | 49 | ND - 3.90 ppm |
2018 | 2.31 ppm | 50 | 46 | ND - 4.10 ppm |
2019 | 2.42 ppm | 55 | 47 | ND - 4.40 ppm |
ppm = parts per million
State and national drinking water standards and health guidelines
EWG Health Guideline 0.14 ppm
The EWG Health Guideline of 0.14 ppm for nitrate was defined by EWG . This health guideline protects against cancer and harm to fetal growth and development.
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 |
---|---|---|
2014-01-06 | 2104-003-0800 | ND |
2014-01-06 | 2104-004-1010 | 4.92 ppm |
2014-01-06 | 2104-005-1020 | 2.15 ppm |
2014-01-06 | 2104-006-1040 | 2.44 ppm |
2014-02-03 | 2104-003-1200 | ND |
2014-02-03 | 2104-004-0950 | 4.86 ppm |
2014-02-03 | 2104-005-1000 | 4.04 ppm |
2014-02-03 | 2104-006-1015 | 4.45 ppm |
2014-03-03 | 2104-003-0800 | 0.520 ppm |
2014-03-03 | 2104-004-1000 | 3.46 ppm |
2014-03-03 | 2104-005-1010 | 2.69 ppm |
2014-03-03 | 2104-006-1050 | 3.03 ppm |
2014-04-07 | 2104-003-0800 | 0.497 ppm |
2014-04-07 | 2104-004-1055 | 3.28 ppm |
2014-04-07 | 2104-005-1100 | 2.64 ppm |
2014-04-07 | 2104-006-1120 | 2.89 ppm |
2014-04-10 | 2104-002-0800 | 0.678 ppm |
2014-05-05 | 2104-003-0800 | 0.542 ppm |
2014-05-05 | 2104-004-1015 | 3.41 ppm |
2014-05-05 | 2104-005-1025 | 2.53 ppm |
2014-05-05 | 2104-006-1045 | 3.07 ppm |
2014-06-02 | 2104-003-0800 | 0.497 ppm |
2014-06-02 | 2104-005-1005 | 2.37 ppm |
2014-06-02 | 2104-006-1025 | 2.33 ppm |
2014-07-07 | 2104-003-0800 | 0.587 ppm |
2014-07-07 | 2104-005-1005 | 2.62 ppm |
2014-07-07 | 2104-006-1020 | 2.62 ppm |
2014-08-04 | 2104-003-1105 | 0.587 ppm |
2014-08-04 | 2104-005-1015 | 2.48 ppm |
2014-08-04 | 2104-006-1035 | 2.48 ppm |
2014-09-02 | 2104-003-0930 | 0.542 ppm |
2014-09-02 | 2104-005-1320 | 2.71 ppm |
2014-09-02 | 2104-006-1340 | 2.71 ppm |
2014-10-20 | 2104-003-0830 | 0.474 ppm |
2014-10-20 | 2104-005-1020 | 2.48 ppm |
2014-10-20 | 2104-006-1040 | 2.48 ppm |
2014-11-03 | 2104-003-0830 | 0.520 ppm |
2014-11-03 | 2104-005-1010 | 2.48 ppm |
2014-11-03 | 2104-006-1025 | 2.48 ppm |
2014-12-01 | 2104-003-0900 | 0.542 ppm |
2014-12-01 | 2104-004-1020 | 4.07 ppm |
2014-12-01 | 2104-005-1030 | 2.48 ppm |
2014-12-01 | 2104-006-1045 | 3.39 ppm |
2015-01-05 | 2104-003-0900 | 0.678 ppm |
2015-01-05 | 2104-004-1000 | 3.84 ppm |
2015-01-05 | 2104-005-1010 | 2.48 ppm |
2015-01-05 | 2104-006-1020 | 3.39 ppm |
2015-02-02 | 2104-003-1010 | 0.700 ppm |
2015-02-02 | 2104-004-1145 | 3.84 ppm |
2015-02-02 | 2104-005-1200 | 2.48 ppm |
2015-02-02 | 2104-006-1215 | 3.16 ppm |
2015-03-02 | 2104-002-1450 | 0.700 ppm |
2015-03-02 | 2104-004-1340 | 3.61 ppm |
2015-03-02 | 2104-006-1310 | 3.61 ppm |
2015-04-06 | 2104-002-1035 | 0.745 ppm |
2015-04-06 | 2104-004-1135 | 3.61 ppm |
2015-04-06 | 2104-006-1150 | 3.61 ppm |
2015-04-09 | 2104-003-0920 | 0.836 ppm |
2015-04-14 | 2104-005-1325 | 2.94 ppm |
2015-05-04 | 2104-003-1430 | 0.813 ppm |
2015-05-04 | 2104-004-1020 | 3.61 ppm |
2015-05-04 | 2104-005-1040 | 2.48 ppm |
2015-05-04 | 2104-006-1055 | 3.16 ppm |
2015-06-01 | 2104-003-0910 | 0.858 ppm |
2015-06-01 | 2104-004-0955 | 3.61 ppm |
2015-06-01 | 2104-005-1005 | 2.48 ppm |
2015-06-01 | 2104-006-1025 | 3.16 ppm |
2015-07-06 | 2104-003-0910 | 0.926 ppm |
2015-07-06 | 2104-004-1015 | 3.84 ppm |
2015-07-06 | 2104-005-1025 | 2.48 ppm |
2015-07-06 | 2104-006-1040 | 3.16 ppm |
2015-08-03 | 2104-003-1035 | 0.949 ppm |
2015-08-03 | 2104-004-1015 | 3.84 ppm |
2015-08-03 | 2104-005-1545 | 3.39 ppm |
2015-08-03 | 2104-006-1525 | ND |
2015-10-05 | 2104-003-0845 | 0.474 ppm |
2015-10-05 | 2104-004-1015 | 3.61 ppm |
2015-10-05 | 2104-006-1405 | 3.61 ppm |
2015-11-02 | 2104-003-0915 | 0.490 ppm |
2015-11-02 | 2104-004-1005 | 3.70 ppm |
2015-11-02 | 2104-005-1015 | 2.70 ppm |
2015-11-02 | 2104-006-1035 | 3.20 ppm |
2015-12-07 | 2104-003-0836 | 0.580 ppm |
2015-12-07 | 2104-004-1025 | 3.60 ppm |
2015-12-07 | 2104-005-1035 | 2.70 ppm |
2015-12-07 | 2104-006-1050 | 3.10 ppm |
2016-01-04 | 2104-003-0910 | 0.700 ppm |
2016-01-04 | 2104-004-1030 | 3.80 ppm |
2016-01-04 | 2104-005-1040 | 2.80 ppm |
2016-01-04 | 2104-006-1100 | 3.30 ppm |
2016-02-08 | 2104-002-1020 | 0.700 ppm |
2016-02-08 | 2104-004-1155 | 4.10 ppm |
2016-02-08 | 2104-005-1210 | 3.10 ppm |
2016-02-08 | 2104-006-1220 | 3.50 ppm |
2016-03-07 | 2104-003-0930 | 0.600 ppm |
2016-03-07 | 2104-004-1035 | 3.50 ppm |
2016-03-07 | 2104-005-1045 | 2.70 ppm |
2016-03-07 | 2104-006-1105 | 3.10 ppm |
2016-04-11 | 2104-004-1035 | 3.80 ppm |
2016-04-11 | 2104-005-1045 | 2.90 ppm |
2016-04-11 | 2104-006-1105 | 3.40 ppm |
2016-04-18 | 2104-003-1450 | 1.30 ppm |
2016-05-02 | 2104-003-0900 | 0.770 ppm |
2016-05-02 | 2104-004-1035 | 3.60 ppm |
2016-05-02 | 2104-005-1045 | 2.80 ppm |
2016-05-02 | 2104-006-1100 | 3.20 ppm |
2016-06-06 | 2104-003-0900 | 0.830 ppm |
2016-06-06 | 2104-004-1025 | 3.60 ppm |
2016-06-06 | 2104-005-1035 | 2.90 ppm |
2016-06-06 | 2104-006-1050 | 3.20 ppm |
2016-07-05 | 2104-003-1030 | 0.840 ppm |
2016-07-05 | 2104-004-1240 | 3.60 ppm |
2016-07-05 | 2104-005-1250 | 2.80 ppm |
2016-07-05 | 2104-006-1310 | 3.20 ppm |
2016-08-01 | 2104-003-0945 | 0.820 ppm |
2016-08-01 | 2104-004-1025 | 3.50 ppm |
2016-08-01 | 2104-005-1035 | 2.80 ppm |
2016-08-01 | 2104-006-1055 | 3.20 ppm |
2016-09-06 | 2104-003-0845 | 0.890 ppm |
2016-09-06 | 2104-004-1215 | 3.90 ppm |
2016-09-06 | 2104-005-1225 | 3.00 ppm |
2016-09-06 | 2104-006-1245 | 3.40 ppm |
2016-10-03 | 2104-003-0905 | 0.860 ppm |
2016-10-03 | 2104-004-1030 | 3.80 ppm |
2016-10-03 | 2104-005-1040 | 2.90 ppm |
2016-10-03 | 2104-006-1055 | 3.20 ppm |
2016-11-07 | 2104-003-0900 | ND |
2016-11-07 | 2104-004-1210 | 3.50 ppm |
2016-11-07 | 2104-005-1220 | 2.70 ppm |
2016-11-07 | 2104-006-1245 | 3.10 ppm |
2016-12-05 | 2104-003-1210 | ND |
2016-12-05 | 2104-004-1035 | 3.70 ppm |
2016-12-05 | 2104-005-1045 | 2.90 ppm |
2016-12-05 | 2104-006-1055 | 3.30 ppm |
2017-01-09 | 2104-004-1030 | 3.80 ppm |
2017-01-09 | 2104-005-1045 | 3.00 ppm |
2017-01-09 | 2104-006-1100 | 3.40 ppm |
2017-01-11 | 2104-003-1100 | ND |
2017-02-06 | 2104-003-1020 | 0.540 ppm |
2017-02-06 | 2104-004-1130 | 3.70 ppm |
2017-02-06 | 2104-005-1135 | 2.90 ppm |
2017-02-06 | 2104-006-1150 | 3.30 ppm |
2017-03-06 | 2104-003-0840 | 0.520 ppm |
2017-03-06 | 2104-004-1015 | 3.60 ppm |
2017-03-06 | 2104-005-1025 | 2.80 ppm |
2017-03-06 | 2104-006-1045 | 3.20 ppm |
2017-04-10 | 2104-003-0840 | 0.770 ppm |
2017-04-10 | 2104-004-1035 | 3.80 ppm |
2017-04-10 | 2104-005-1045 | 3.10 ppm |
2017-04-10 | 2104-006-1125 | 3.50 ppm |
2017-05-01 | 2104-003-0830 | 0.770 ppm |
2017-05-01 | 2104-004-1030 | 3.80 ppm |
2017-05-01 | 2104-005-1040 | 3.00 ppm |
2017-05-01 | 2104-006-1110 | 3.40 ppm |
2017-06-05 | 2104-002-1010 | 0.580 ppm |
2017-06-05 | 2104-003-0920 | 0.570 ppm |
2017-06-05 | 2104-003-1010 | 0.580 ppm |
2017-06-05 | 2104-004-1100 | 3.70 ppm |
2017-06-05 | 2104-005-1115 | 2.80 ppm |
2017-06-05 | 2104-006-1150 | 3.30 ppm |
2017-07-10 | 2104-002-1000 | 0.800 ppm |
2017-07-10 | 2104-003-0945 | 0.810 ppm |
2017-07-10 | 2104-004-1100 | 3.60 ppm |
2017-07-10 | 2104-005-1110 | 2.80 ppm |
2017-07-10 | 2104-006-1135 | 3.30 ppm |
2017-08-07 | 2104-002-0745 | 0.660 ppm |
2017-08-07 | 2104-003-1015 | 0.650 ppm |
2017-08-07 | 2104-004-0845 | 3.70 ppm |
2017-08-07 | 2104-005-0855 | 2.80 ppm |
2017-08-07 | 2104-006-0915 | 3.20 ppm |
2017-09-11 | 2104-002-1005 | 0.660 ppm |
2017-09-11 | 2104-003-1000 | 0.660 ppm |
2017-09-11 | 2104-004-1105 | 3.50 ppm |
2017-09-11 | 2104-005-1115 | 2.60 ppm |
2017-09-11 | 2104-006-1445 | 3.10 ppm |
2017-10-02 | 2104-003-0935 | 0.650 ppm |
2017-10-02 | 2104-005-1015 | 2.80 ppm |
2017-10-02 | 2104-006-1030 | 2.80 ppm |
2017-11-06 | 2104-003-0900 | 0.520 ppm |
2017-11-06 | 2104-004-1040 | 3.90 ppm |
2017-11-06 | 2104-005-1050 | 2.80 ppm |
2017-11-06 | 2104-006-1115 | 3.30 ppm |
2017-12-04 | 2104-003-0830 | ND |
2017-12-04 | 2104-005-1020 | 2.80 ppm |
2017-12-04 | 2104-006-1035 | 2.80 ppm |
2018-01-08 | 2104-003-0830 | ND |
2018-01-08 | 2104-004-1010 | 3.90 ppm |
2018-01-08 | 2104-005-1020 | 2.80 ppm |
2018-01-08 | 2104-006-1045 | 3.40 ppm |
2018-02-05 | 2104-003-0845 | 0.480 ppm |
2018-03-01 | 2104-003-0825 | 0.460 ppm |
2018-03-05 | 2104-004-1425 | 4.10 ppm |
2018-03-05 | 2104-005-1435 | 3.00 ppm |
2018-03-05 | 2104-006-1450 | 3.60 ppm |
2018-04-02 | 2104-002-0955 | 0.470 ppm |
2018-04-02 | 2104-003-0850 | 0.880 ppm |
2018-04-02 | 2104-004-1100 | 3.90 ppm |
2018-04-02 | 2104-006-1135 | 4.00 ppm |
2018-05-07 | 2104-003-1020 | 0.470 ppm |
2018-05-07 | 2104-004-1015 | 4.00 ppm |
2018-05-07 | 2104-005-1025 | 3.00 ppm |
2018-05-07 | 2104-006-1055 | 3.50 ppm |
2018-06-04 | 2104-003-0910 | 0.470 ppm |
2018-06-04 | 2104-004-1025 | 3.80 ppm |
2018-06-04 | 2104-006-1040 | 3.30 ppm |
2018-06-07 | 2104-005-1010 | 2.90 ppm |
2018-07-09 | 2104-002-0930 | 0.650 ppm |
2018-07-09 | 2104-003-0930 | 0.710 ppm |
2018-07-09 | 2104-004-1000 | 4.10 ppm |
2018-07-09 | 2104-005-0925 | 2.90 ppm |
2018-07-09 | 2104-006-0940 | 2.90 ppm |
2018-08-06 | 2104-002-1025 | 0.520 ppm |
2018-08-06 | 2104-003-0830 | 0.560 ppm |
2018-08-06 | 2104-004-1125 | 3.80 ppm |
2018-08-06 | 2104-005-1135 | 2.90 ppm |
2018-08-06 | 2104-006-1150 | 3.30 ppm |
2018-09-10 | 2104-002-0920 | ND |
2018-09-10 | 2104-003-0900 | 0.490 ppm |
2018-09-10 | 2104-004-1020 | 3.60 ppm |
2018-09-10 | 2104-005-1030 | 2.80 ppm |
2018-09-10 | 2104-006-1045 | 3.10 ppm |
2018-10-08 | 2104-002-0945 | 0.470 ppm |
2018-10-08 | 2104-003-0845 | 0.560 ppm |
2018-10-08 | 2104-004-1055 | 3.70 ppm |
2018-10-08 | 2104-005-1110 | 2.80 ppm |
2018-10-08 | 2104-006-1130 | 3.30 ppm |
2018-11-05 | 2104-002-0945 | ND |
2018-11-05 | 2104-003-0845 | 0.530 ppm |
2018-11-05 | 2104-004-1045 | 3.60 ppm |
2018-11-05 | 2104-005-1055 | 2.70 ppm |
2018-11-05 | 2104-006-1110 | 3.20 ppm |
2018-12-03 | 2104-002-0945 | ND |
2018-12-03 | 2104-004-1040 | 3.80 ppm |
2018-12-03 | 2104-005-1050 | 2.90 ppm |
2018-12-03 | 2104-006-1105 | 3.40 ppm |
2019-01-07 | 2104-002-1015 | ND |
2019-01-07 | 2104-004-1110 | 4.00 ppm |
2019-01-07 | 2104-005-1120 | 3.10 ppm |
2019-01-07 | 2104-006-1135 | 3.60 ppm |
2019-02-11 | 2104-004-1120 | 4.10 ppm |
2019-02-11 | 2104-005-1130 | 3.10 ppm |
2019-02-11 | 2104-006-1150 | 3.60 ppm |
2019-03-04 | 2104-002-1000 | 0.540 ppm |
2019-03-04 | 2104-004-1100 | 4.10 ppm |
2019-03-04 | 2104-005-1110 | 3.10 ppm |
2019-03-04 | 2104-006-1130 | 3.60 ppm |
2019-04-01 | 2104-002-0805 | 0.480 ppm |
2019-04-01 | 2104-003-1015 | ND |
2019-04-01 | 2104-004-1105 | 3.90 ppm |
2019-04-01 | 2104-005-1115 | 3.10 ppm |
2019-04-01 | 2104-006-1135 | 3.50 ppm |
2019-05-06 | 2104-002-0945 | ND |
2019-05-06 | 2104-003-0830 | 0.470 ppm |
2019-05-06 | 2104-004-1035 | 3.90 ppm |
2019-05-06 | 2104-005-1045 | 3.10 ppm |
2019-05-06 | 2104-006-1100 | 3.50 ppm |
2019-06-03 | 2104-002-1015 | ND |
2019-06-03 | 2104-003-0905 | 0.470 ppm |
2019-06-03 | 2104-004-1120 | 4.00 ppm |
2019-06-03 | 2104-005-1130 | 3.10 ppm |
2019-06-03 | 2104-006-1145 | 3.60 ppm |
2019-07-08 | 2104-002-1005 | 0.460 ppm |
2019-07-08 | 2104-003-0830 | 0.490 ppm |
2019-07-08 | 2104-004-1115 | 3.90 ppm |
2019-07-08 | 2104-005-1120 | 3.10 ppm |
2019-07-08 | 2104-006-1140 | 3.60 ppm |
2019-08-05 | 2104-002-0950 | 0.470 ppm |
2019-08-05 | 2104-003-0910 | 0.520 ppm |
2019-08-05 | 2104-004-1045 | 4.40 ppm |
2019-08-05 | 2104-005-1055 | 3.10 ppm |
2019-08-05 | 2104-006-1115 | 3.20 ppm |
2019-09-09 | 2104-002-1110 | ND |
2019-09-09 | 2104-003-0830 | 0.480 ppm |
2019-09-09 | 2104-004-1205 | 3.90 ppm |
2019-09-09 | 2104-005-1210 | 3.00 ppm |
2019-09-09 | 2104-006-1245 | 3.50 ppm |
2019-10-07 | 2104-002-1024 | 0.450 ppm |
2019-10-07 | 2104-003-0855 | 0.510 ppm |
2019-10-07 | 2104-004-1104 | 4.10 ppm |
2019-10-07 | 2104-005-1122 | 3.20 ppm |
2019-10-07 | 2104-006-1146 | 3.60 ppm |
2019-11-04 | 2104-002-1000 | ND |
2019-11-04 | 2104-003-0950 | ND |
2019-11-04 | 2104-004-1105 | 4.10 ppm |
2019-11-04 | 2104-005-1110 | 3.20 ppm |
2019-11-04 | 2104-006-1125 | 3.70 ppm |
2019-12-02 | 2104-004-1020 | 3.80 ppm |
2019-12-02 | 2104-005-1030 | 3.00 ppm |
2019-12-02 | 2104-006-1100 | 3.50 ppm |
2019-12-04 | 2104-002-1010 | ND |