Nitrate and nitrite
Mountain Water Company
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.
210
Samples
0
Samples exceeding legal limit (MCL)
210
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 | 0.857 ppm | 35 | 35 | 0.390 ppm - 2.63 ppm |
| 2015 | 0.816 ppm | 34 | 34 | 0.360 ppm - 2.93 ppm |
| 2016 | 0.738 ppm | 35 | 35 | 0.300 ppm - 2.59 ppm |
| 2017 | 0.929 ppm | 38 | 38 | 0.380 ppm - 2.96 ppm |
| 2018 | 1.10 ppm | 35 | 35 | 0.470 ppm - 2.84 ppm |
| 2019 | 0.985 ppm | 33 | 33 | 0.410 ppm - 3.45 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 |
|---|---|---|
| 2014-08-20 | B14082029-001A | 0.740 ppm |
| 2014-08-20 | B14082029-002A | 0.430 ppm |
| 2014-08-20 | B14082029-003A | 0.730 ppm |
| 2014-08-20 | B14082029-004A | 0.390 ppm |
| 2014-08-20 | B14082029-005A | 1.20 ppm |
| 2014-08-20 | B14082029-006A | 0.930 ppm |
| 2014-08-20 | B14082029-007A | 0.590 ppm |
| 2014-08-20 | B14082029-008A | 2.63 ppm |
| 2014-08-26 | B14082497-001A | 0.460 ppm |
| 2014-08-26 | B14082497-002A | 1.62 ppm |
| 2014-08-26 | B14082497-003A | 1.04 ppm |
| 2014-08-26 | B14082497-004A | 0.410 ppm |
| 2014-08-26 | B14082497-005A | 0.440 ppm |
| 2014-09-08 | B14090737-001A | 0.480 ppm |
| 2014-09-10 | B14091071-001D | 0.480 ppm |
| 2014-09-10 | B14091071-002D | 0.960 ppm |
| 2014-09-10 | B14091071-003D | 0.990 ppm |
| 2014-09-30 | B14100103-001A | 0.950 ppm |
| 2014-09-30 | B14100103-002A | 0.580 ppm |
| 2014-09-30 | B14100103-003A | 0.750 ppm |
| 2014-09-30 | B14100103-004A | 1.46 ppm |
| 2014-10-08 | B14100810-001A | 0.580 ppm |
| 2014-10-09 | B14100938-001A | 1.34 ppm |
| 2014-10-09 | B14100938-002A | 0.630 ppm |
| 2014-10-09 | B14100938-003A | 0.660 ppm |
| 2014-11-06 | B14110557-001D | 0.830 ppm |
| 2014-11-06 | B14110557-002D | 1.35 ppm |
| 2014-11-06 | B14110557-003D | 1.28 ppm |
| 2014-11-20 | B14111576-001D | 0.530 ppm |
| 2014-11-20 | B14111576-002D | 1.11 ppm |
| 2014-11-20 | B14111576-003D | 0.840 ppm |
| 2014-11-24 | B14111861-001D | 0.930 ppm |
| 2014-11-24 | B14111861-002D | 0.510 ppm |
| 2014-12-10 | B14121087-001A | 0.660 ppm |
| 2014-12-22 | B14121939-001D | 0.500 ppm |
| 2015-01-29 | B15011910-001D | 0.580 ppm |
| 2015-05-19 | B15051656-002A | 0.500 ppm |
| 2015-08-31 | B15090069-001A | 0.360 ppm |
| 2015-08-31 | B15090069-002A | 0.860 ppm |
| 2015-08-31 | B15090069-003A | 0.970 ppm |
| 2015-08-31 | B15090069-004A | 1.49 ppm |
| 2015-08-31 | B15090069-005A | 1.18 ppm |
| 2015-08-31 | B15090069-006A | 0.860 ppm |
| 2015-09-16 | B15091536-001A | 0.570 ppm |
| 2015-09-16 | B15091536-002A | 0.980 ppm |
| 2015-09-16 | B15091536-003A | 0.460 ppm |
| 2015-09-16 | B15091536-004A | 0.410 ppm |
| 2015-09-16 | B15091536-005A | 0.460 ppm |
| 2015-09-16 | B15091536-006A | 0.950 ppm |
| 2015-09-29 | B15092516-001D | 0.690 ppm |
| 2015-09-29 | B15092516-002D | 0.530 ppm |
| 2015-09-29 | B15092516-003D | 0.370 ppm |
| 2015-09-29 | B15092516-004D | 0.600 ppm |
| 2015-10-15 | B15101460-001A | 0.570 ppm |
| 2015-10-15 | B15101460-002A | 0.510 ppm |
| 2015-10-15 | B15101460-003A | 1.14 ppm |
| 2015-10-15 | B15101460-004A | 1.36 ppm |
| 2015-10-15 | B15101460-005A | 2.93 ppm |
| 2015-10-20 | B15101683-001D | 0.460 ppm |
| 2015-10-20 | B15101683-002D | 1.46 ppm |
| 2015-10-20 | B15101683-003D | 0.590 ppm |
| 2015-10-20 | B15101683-004D | 0.580 ppm |
| 2015-10-22 | B15101954-001A | 0.900 ppm |
| 2015-10-22 | B15101954-002A | 0.860 ppm |
| 2015-10-22 | B15101954-003A | 0.580 ppm |
| 2015-10-22 | B15101954-004A | 1.18 ppm |
| 2015-10-27 | B15102213-001D | 0.640 ppm |
| 2015-10-27 | B15102213-002D | 0.510 ppm |
| 2015-10-27 | B15102213-003D | 0.640 ppm |
| 2016-05-24 | B16051927-001A | 0.450 ppm |
| 2016-05-24 | B16051932-001A | 0.480 ppm |
| 2016-08-23 | B16082328-001A | 0.430 ppm |
| 2016-08-23 | B16082328-002A | 0.400 ppm |
| 2016-09-14 | B16091275-008A | 0.850 ppm |
| 2016-09-14 | B16091275-009A | 0.520 ppm |
| 2016-09-14 | B16091275-010A | 0.570 ppm |
| 2016-10-05 | B16100470-001A | 0.510 ppm |
| 2016-10-05 | B16100470-002A | 0.580 ppm |
| 2016-10-05 | B16100470-003A | 0.870 ppm |
| 2016-10-05 | B16100470-004A | 0.400 ppm |
| 2016-10-05 | B16100470-005A | 0.380 ppm |
| 2016-10-10 | B16100735-001D | 0.580 ppm |
| 2016-10-10 | B16100735-002D | 0.400 ppm |
| 2016-10-10 | B16100735-003D | 0.560 ppm |
| 2016-10-18 | B16101448-001A | 0.780 ppm |
| 2016-10-19 | B16101620-001A | 0.850 ppm |
| 2016-10-19 | B16101620-002A | 0.790 ppm |
| 2016-10-26 | B16102234-001A | 0.600 ppm |
| 2016-11-02 | B16110416-001A | 0.340 ppm |
| 2016-11-02 | B16110416-002A | 1.17 ppm |
| 2016-11-02 | B16110416-003A | 1.09 ppm |
| 2016-11-02 | B16110416-004A | 0.470 ppm |
| 2016-11-02 | B16110416-005A | 0.540 ppm |
| 2016-11-09 | B16110855-001D | 1.02 ppm |
| 2016-11-09 | B16110855-002D | 1.48 ppm |
| 2016-11-09 | B16110855-003D | 0.300 ppm |
| 2016-11-09 | B16110855-004D | 1.19 ppm |
| 2016-11-16 | B16111413-001D | 0.820 ppm |
| 2016-11-16 | B16111413-002D | 0.940 ppm |
| 2016-11-16 | B16111413-003D | 2.59 ppm |
| 2016-11-30 | B16120054-001A | 0.520 ppm |
| 2016-11-30 | B16120054-002A | 0.520 ppm |
| 2016-11-30 | B16120054-003A | 0.560 ppm |
| 2016-11-30 | B16120054-004A | 1.28 ppm |
| 2017-01-24 | B17011515-001A | 0.400 ppm |
| 2017-03-08 | H17030154-001C | 0.380 ppm |
| 2017-03-08 | H17030156-001C | 0.380 ppm |
| 2017-03-08 | H17030158-001C | 0.550 ppm |
| 2017-09-06 | B17090541-001A | 0.690 ppm |
| 2017-09-06 | B17090541-002A | 0.430 ppm |
| 2017-09-06 | B17090541-003A | 0.440 ppm |
| 2017-09-06 | B17090541-004A | 0.450 ppm |
| 2017-09-06 | B17090541-005A | 0.630 ppm |
| 2017-09-13 | B17091233-001A | 0.710 ppm |
| 2017-09-13 | B17091233-002A | 1.68 ppm |
| 2017-09-13 | B17091233-003A | 1.48 ppm |
| 2017-09-13 | B17091233-004A | 0.520 ppm |
| 2017-09-13 | B17091233-005A | 0.480 ppm |
| 2017-09-19 | B17091738-001A | 1.01 ppm |
| 2017-09-19 | B17091738-002A | 1.41 ppm |
| 2017-09-19 | B17091738-003A | 0.830 ppm |
| 2017-09-19 | B17091738-004A | 1.61 ppm |
| 2017-09-19 | B17091738-005A | 0.690 ppm |
| 2017-09-26 | B17092349-001D | 1.83 ppm |
| 2017-09-26 | B17092349-002D | 0.550 ppm |
| 2017-09-26 | B17092349-003D | 0.490 ppm |
| 2017-10-03 | B17100298-001D | 0.750 ppm |
| 2017-10-03 | B17100298-002D | 0.920 ppm |
| 2017-10-03 | B17100298-003D | 1.10 ppm |
| 2017-10-03 | B17100298-004D | 1.06 ppm |
| 2017-10-11 | B17101115-001D | 1.19 ppm |
| 2017-10-11 | B17101115-002D | 0.580 ppm |
| 2017-10-11 | B17101115-003D | 1.41 ppm |
| 2017-10-11 | B17101115-004D | 1.45 ppm |
| 2017-10-11 | B17101120-001D | 0.520 ppm |
| 2017-11-01 | B17110168-004A | 1.63 ppm |
| 2017-11-14 | B17111245-001A | 1.07 ppm |
| 2017-11-14 | B17111245-002A | 0.620 ppm |
| 2017-11-14 | B17111245-003A | 1.000 ppm |
| 2017-11-14 | B17111245-004A | 0.710 ppm |
| 2017-11-14 | B17111245-005A | 2.96 ppm |
| 2017-11-14 | B17111245-006A | 0.700 ppm |
| 2018-05-15 | B18051508-001C | 0.750 ppm |
| 2018-05-15 | B18051514-001C | 0.520 ppm |
| 2018-05-23 | B18052237-001C | 0.600 ppm |
| 2018-06-05 | B18060423-001C | 0.820 ppm |
| 2018-06-05 | B18060546-001A | 0.530 ppm |
| 2018-06-19 | B18061823-001C | 0.940 ppm |
| 2018-06-19 | B18061914-001A | 1.15 ppm |
| 2018-06-19 | B18061915-001A | 1.04 ppm |
| 2018-07-17 | B18071571-001C | 0.580 ppm |
| 2018-07-17 | B18071604-001C | 1.08 ppm |
| 2018-07-18 | B18071741-001C | 1.60 ppm |
| 2018-07-18 | B18071799-001C | 0.780 ppm |
| 2018-07-31 | B18080102-001A | 2.18 ppm |
| 2018-08-14 | B18081504-001C | 1.18 ppm |
| 2018-08-14 | B18081537-001C | 0.780 ppm |
| 2018-09-05 | B18090357-001C | 0.870 ppm |
| 2018-09-11 | B18091026-001A | 1.18 ppm |
| 2018-09-11 | B18091031-001A | 0.600 ppm |
| 2018-09-11 | B18091032-001A | 0.470 ppm |
| 2018-09-11 | B18091034-001A | 0.520 ppm |
| 2018-09-11 | B18091036-001A | 1.40 ppm |
| 2018-09-12 | B18091218-001A | 0.650 ppm |
| 2018-09-12 | B18091220-001A | 1.80 ppm |
| 2018-09-12 | B18091222-001A | 0.530 ppm |
| 2018-09-12 | B18091223-001A | 1.20 ppm |
| 2018-09-18 | B18091824-001A | 1.49 ppm |
| 2018-09-18 | B18091825-001A | 1.79 ppm |
| 2018-09-18 | B18091826-001A | 1.72 ppm |
| 2018-09-18 | B18091827-001A | 1.27 ppm |
| 2018-09-18 | B18091828-001A | 1.26 ppm |
| 2018-09-19 | B18091949-001A | 2.84 ppm |
| 2018-09-19 | B18091950-001A | 1.50 ppm |
| 2018-09-19 | B18091951-001A | 1.46 ppm |
| 2018-09-19 | B18091952-001A | 0.770 ppm |
| 2018-09-19 | B18091953-001A | 0.540 ppm |
| 2019-05-07 | B19050690-001A | 0.510 ppm |
| 2019-05-14 | B19051387-001C | 3.45 ppm |
| 2019-05-22 | B19052006-001C | 1.81 ppm |
| 2019-06-04 | B19060314-001C | 1.55 ppm |
| 2019-06-11 | B19061058-001C | 2.36 ppm |
| 2019-06-18 | B19061773-001C | 1.33 ppm |
| 2019-07-09 | B19070912-001C | 0.470 ppm |
| 2019-07-17 | B19071738-001C | 1.10 ppm |
| 2019-07-23 | B19072150-001C | 0.410 ppm |
| 2019-08-07 | B19080745-001C | 1.40 ppm |
| 2019-08-13 | B19081351-001C | 0.440 ppm |
| 2019-08-20 | B19082022-001C | 0.740 ppm |
| 2019-09-10 | B19090958-001A | 0.950 ppm |
| 2019-09-10 | B19091000-001A | 1.17 ppm |
| 2019-09-10 | B19091001-001A | 1.09 ppm |
| 2019-09-10 | B19091002-001A | 0.970 ppm |
| 2019-09-10 | B19091004-001A | 0.710 ppm |
| 2019-09-10 | B19091005-001A | 0.520 ppm |
| 2019-09-10 | B19091006-001A | 0.560 ppm |
| 2019-09-10 | B19091007-001A | 0.620 ppm |
| 2019-09-17 | B19091777-001A | 0.500 ppm |
| 2019-09-17 | B19091780-001A | 0.480 ppm |
| 2019-09-17 | B19091781-001A | 0.780 ppm |
| 2019-09-17 | B19091782-001A | 0.590 ppm |
| 2019-09-17 | B19091783-001A | 0.480 ppm |
| 2019-09-17 | B19091784-001A | 0.600 ppm |
| 2019-09-17 | B19091786-001A | 0.430 ppm |
| 2019-09-17 | B19091788-001A | 0.580 ppm |
| 2019-09-24 | B19092437-001A | 1.71 ppm |
| 2019-09-24 | B19092439-001A | 0.670 ppm |
| 2019-09-24 | B19092440-001A | 1.16 ppm |
| 2019-10-08 | B19100880-001A | 0.670 ppm |
| 2019-10-08 | B19100882-001A | 1.70 ppm |