Nitrate
Lima
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.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2018 | 2.99 ppm | 25 | 21 | ND - 10.00 ppm |
| 2019 | 5.02 ppm | 78 | 76 | ND - 13.0 ppm |
| 2020 | 2.70 ppm | 50 | 45 | ND - 6.80 ppm |
| 2021 | 2.80 ppm | 50 | 39 | ND - 6.40 ppm |
| 2022 | 2.73 ppm | 50 | 39 | ND - 6.90 ppm |
| 2023 | 2.52 ppm | 38 | 38 | 0.0600 ppm - 5.70 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 |
|---|---|---|
| 2018-01-22 | 8013393-01 | 2.70 ppm |
| 2018-01-22 | 8013393-02 | ND |
| 2018-02-07 | 8021243-01 | 0.750 ppm |
| 2018-02-07 | 8021243-02 | ND |
| 2018-03-13 | 8032335-01 | 3.60 ppm |
| 2018-03-13 | 8032335-02 | 3.80 ppm |
| 2018-04-16 | 8042946-01 | 7.50 ppm |
| 2018-04-16 | 8042946-02 | 1.20 ppm |
| 2018-05-03 | 8051007-01 | 9.00 ppm |
| 2018-05-03 | 8051007-02 | 0.0500 ppm |
| 2018-06-13 | 8062625-01 | 7.60 ppm |
| 2018-06-13 | 8062625-02 | 5.60 ppm |
| 2018-07-23 | 8074333-01 | 10.00 ppm |
| 2018-08-22 | 8084586-01 | 0.0400 ppm |
| 2018-08-22 | 8084586-02 | ND |
| 2018-09-10 | 8091578-01 | 4.10 ppm |
| 2018-09-10 | 8091578-02 | ND |
| 2018-09-26 | 8095536-01 | 7.00 ppm |
| 2018-09-26 | 8095536-02 | 0.170 ppm |
| 2018-10-17 | 8103740-01 | 0.360 ppm |
| 2018-10-17 | 8103740-02 | 0.120 ppm |
| 2018-11-08 | 8111867-01 | 6.50 ppm |
| 2018-11-08 | 8111867-02 | 0.160 ppm |
| 2018-12-26 | 8124259-01 | 4.30 ppm |
| 2018-12-26 | 8124259-02 | 0.200 ppm |
| 2019-01-30 | 9014615-01 | 7.40 ppm |
| 2019-01-30 | 9014615-02 | 0.160 ppm |
| 2019-02-18 | 9023058-01 | 6.90 ppm |
| 2019-02-18 | 9023058-02 | 0.120 ppm |
| 2019-03-11 | 9031663-01 | 8.10 ppm |
| 2019-03-11 | 9031663-02 | 0.0800 ppm |
| 2019-04-01 | 9040286-01 | 0.170 ppm |
| 2019-04-01 | 9040286-02 | 0.170 ppm |
| 2019-05-01 | 9050420-01 | 7.60 ppm |
| 2019-05-01 | 9050420-02 | 0.200 ppm |
| 2019-05-08 | 9052110-01 | 1.000 ppm |
| 2019-05-14 | 9053270-01 | 0.230 ppm |
| 2019-05-14 | 9053270-03 | 4.80 ppm |
| 2019-05-23 | 9054863-07 | 13.0 ppm |
| 2019-05-23 | 9054863-08 | 13.0 ppm |
| 2019-05-23 | 9055236-01 | 11.0 ppm |
| 2019-05-23 | 9055236-02 | 7.80 ppm |
| 2019-05-23 | 9055236-03 | 8.10 ppm |
| 2019-05-24 | 9055236-04 | 10.00 ppm |
| 2019-05-24 | 9055236-05 | 13.0 ppm |
| 2019-05-24 | 9055236-06 | 13.0 ppm |
| 2019-05-25 | 9055236-07 | 13.0 ppm |
| 2019-05-25 | 9055236-08 | 13.0 ppm |
| 2019-05-25 | 9055236-09 | 13.0 ppm |
| 2019-05-28 | 9055736-01 | 13.0 ppm |
| 2019-05-28 | 9055736-02 | 13.0 ppm |
| 2019-05-28 | 9055736-03 | 13.0 ppm |
| 2019-05-29 | 9055736-04 | 13.0 ppm |
| 2019-05-29 | 9055736-05 | 13.0 ppm |
| 2019-05-29 | 9055736-06 | 13.0 ppm |
| 2019-06-05 | 9061143-01 | 0.250 ppm |
| 2019-06-05 | 9061143-03 | 3.30 ppm |
| 2019-06-19 | 9063819-01 | 6.70 ppm |
| 2019-06-19 | 9063819-02 | 0.120 ppm |
| 2019-06-26 | 9065194-01 | 7.50 ppm |
| 2019-06-26 | 9065194-02 | 0.200 ppm |
| 2019-07-01 | 9070357-01 | 0.140 ppm |
| 2019-07-01 | 9070357-03 | 7.30 ppm |
| 2019-07-10 | 9072286-01 | 6.10 ppm |
| 2019-07-10 | 9072286-02 | 0.240 ppm |
| 2019-07-17 | 9073913-01 | 7.40 ppm |
| 2019-07-17 | 9073913-02 | 0.200 ppm |
| 2019-07-23 | 9074900-01 | 11.0 ppm |
| 2019-07-23 | 9074900-02 | 0.200 ppm |
| 2019-07-30 | 9075997-02 | 0.230 ppm |
| 2019-07-30 | 9075997-03 | 5.80 ppm |
| 2019-08-07 | 9081668-01 | 5.20 ppm |
| 2019-08-07 | 9081668-02 | 0.250 ppm |
| 2019-08-19 | 9084130-01 | 5.40 ppm |
| 2019-08-19 | 9084130-02 | 0.200 ppm |
| 2019-08-27 | 9085778-02 | 0.220 ppm |
| 2019-08-27 | 9085778-03 | 5.50 ppm |
| 2019-09-03 | 9090389-01 | 0.160 ppm |
| 2019-09-03 | 9090389-03 | 6.00 ppm |
| 2019-09-09 | 9091504-01 | 0.120 ppm |
| 2019-09-09 | 9091504-03 | 5.00 ppm |
| 2019-09-16 | 9093090-01 | 6.50 ppm |
| 2019-09-16 | 9093090-02 | 0.230 ppm |
| 2019-09-23 | 9094484-01 | 4.90 ppm |
| 2019-09-23 | 9094484-02 | 0.200 ppm |
| 2019-10-02 | 9100827-01 | 0.200 ppm |
| 2019-10-02 | 9100827-03 | 5.90 ppm |
| 2019-10-09 | 9102376-01 | 5.70 ppm |
| 2019-10-09 | 9102376-02 | 0.190 ppm |
| 2019-10-16 | 9103726-01 | 5.70 ppm |
| 2019-10-16 | 9103726-02 | ND |
| 2019-10-22 | 9104628-01 | 5.20 ppm |
| 2019-10-22 | 9104628-02 | ND |
| 2019-10-29 | 9105760-01 | 5.00 ppm |
| 2019-10-29 | 9105760-02 | 0.0400 ppm |
| 2019-11-12 | 9112014-01 | 5.50 ppm |
| 2019-11-12 | 9112014-02 | 0.0400 ppm |
| 2019-11-25 | 9114509-01 | 7.00 ppm |
| 2019-11-25 | 9114509-02 | 0.1000 ppm |
| 2019-12-18 | 9123898-01 | 6.80 ppm |
| 2019-12-18 | 9123898-02 | 0.220 ppm |
| 2019-12-30 | 9124855-01 | 0.200 ppm |
| 2019-12-30 | 9124855-03 | 4.50 ppm |
| 2020-01-08 | 0011600-01 | 5.20 ppm |
| 2020-01-08 | 0011600-02 | 0.280 ppm |
| 2020-01-21 | 0013826-01 | 0.120 ppm |
| 2020-01-21 | 0013826-03 | 4.80 ppm |
| 2020-02-04 | 0020760-01 | 4.70 ppm |
| 2020-02-04 | 0020760-02 | 0.0900 ppm |
| 2020-02-19 | 0023459-01 | 6.30 ppm |
| 2020-02-19 | 0023459-02 | 0.120 ppm |
| 2020-03-02 | 0030285-01 | 4.80 ppm |
| 2020-03-02 | 0030285-02 | ND |
| 2020-03-23 | 0034069-01 | 6.40 ppm |
| 2020-03-23 | 0034069-02 | 0.220 ppm |
| 2020-04-09 | 0042212-01 | 4.30 ppm |
| 2020-04-09 | 0042212-02 | 0.210 ppm |
| 2020-04-27 | 0044848-01 | 6.50 ppm |
| 2020-04-27 | 0044848-02 | 0.210 ppm |
| 2020-05-14 | 0052863-01 | 0.210 ppm |
| 2020-05-14 | 0052863-02 | 0.200 ppm |
| 2020-06-04 | 0061361-01 | 5.60 ppm |
| 2020-06-04 | 0061361-02 | 0.140 ppm |
| 2020-06-16 | 0063588-01 | ND |
| 2020-06-16 | 0063588-03 | 5.70 ppm |
| 2020-06-30 | 0070131-01 | 4.60 ppm |
| 2020-06-30 | 0070131-02 | ND |
| 2020-07-14 | 0072862-01 | 4.50 ppm |
| 2020-07-14 | 0072862-02 | 0.0500 ppm |
| 2020-07-28 | 0075960-01 | 0.180 ppm |
| 2020-07-28 | 0075960-03 | 3.70 ppm |
| 2020-08-13 | 0083310-01 | 0.150 ppm |
| 2020-08-13 | 0083310-03 | 5.60 ppm |
| 2020-08-27 | 0086024-01 | 0.270 ppm |
| 2020-08-27 | 0086024-03 | 5.30 ppm |
| 2020-09-09 | 0092196-01 | 0.240 ppm |
| 2020-09-09 | 0092196-03 | 6.20 ppm |
| 2020-09-21 | 0094612-01 | 6.20 ppm |
| 2020-09-21 | 0094612-02 | 0.0800 ppm |
| 2020-10-07 | 0101739-01 | 6.70 ppm |
| 2020-10-07 | 0101739-02 | 0.0400 ppm |
| 2020-10-19 | 0103769-01 | ND |
| 2020-10-19 | 0103769-03 | 5.10 ppm |
| 2020-11-02 | 0110318-01 | 5.60 ppm |
| 2020-11-02 | 0110318-02 | 0.0500 ppm |
| 2020-11-16 | 0112998-01 | 5.70 ppm |
| 2020-11-16 | 0112998-02 | ND |
| 2020-12-01 | 0120411-01 | 6.10 ppm |
| 2020-12-01 | 0120411-02 | 0.0600 ppm |
| 2020-12-17 | 0123655-02 | 0.310 ppm |
| 2020-12-17 | 0123655-03 | 6.80 ppm |
| 2020-12-28 | 0124531-01 | 5.30 ppm |
| 2020-12-28 | 0124531-02 | 0.240 ppm |
| 2021-01-11 | EA01701-01 | 5.40 ppm |
| 2021-01-11 | EA01701-02 | 0.130 ppm |
| 2021-01-28 | EA04765-01 | 5.40 ppm |
| 2021-01-28 | EA04765-02 | 0.240 ppm |
| 2021-02-10 | EB02222-01 | 4.00 ppm |
| 2021-02-10 | EB02222-02 | 0.220 ppm |
| 2021-02-22 | EB03592-01 | 5.10 ppm |
| 2021-02-22 | EB03592-02 | 0.200 ppm |
| 2021-03-08 | EC01664-01 | 4.50 ppm |
| 2021-03-08 | EC01664-02 | 0.220 ppm |
| 2021-03-22 | EC04198-01 | 4.90 ppm |
| 2021-03-22 | EC04198-02 | 0.0900 ppm |
| 2021-04-06 | ED01063-01 | 4.70 ppm |
| 2021-04-06 | ED01063-02 | 0.0900 ppm |
| 2021-04-21 | ED04315-01 | 5.00 ppm |
| 2021-04-21 | ED04315-02 | 0.0900 ppm |
| 2021-05-06 | EE01425-01 | 5.20 ppm |
| 2021-05-06 | EE01425-02 | 0.0600 ppm |
| 2021-05-17 | EE03421-01 | 4.20 ppm |
| 2021-06-01 | EF00438-01 | 6.10 ppm |
| 2021-06-01 | EF00438-02 | ND |
| 2021-06-16 | EF03619-01 | 6.40 ppm |
| 2021-06-23 | EF04942-01 | 5.40 ppm |
| 2021-06-23 | EF04942-02 | 0.0600 ppm |
| 2021-07-08 | EG01694-01 | 5.30 ppm |
| 2021-07-08 | EG01694-02 | ND |
| 2021-07-19 | EG03802-01 | 5.70 ppm |
| 2021-07-19 | EG03802-02 | 0.0400 ppm |
| 2021-08-02 | EH00550-01 | 5.50 ppm |
| 2021-08-02 | EH00550-02 | ND |
| 2021-08-17 | EH03978-01 | 5.80 ppm |
| 2021-08-17 | EH03978-02 | ND |
| 2021-09-01 | EI00450-01 | ND |
| 2021-09-01 | EI00450-03 | 5.30 ppm |
| 2021-09-15 | EI03178-01 | 6.00 ppm |
| 2021-09-15 | EI03178-02 | ND |
| 2021-09-29 | EI05645-01 | 6.30 ppm |
| 2021-09-29 | EI05645-02 | ND |
| 2021-10-11 | EJ02177-01 | 5.90 ppm |
| 2021-10-11 | EJ02177-02 | 0.0300 ppm |
| 2021-10-25 | EJ04810-01 | 5.60 ppm |
| 2021-10-25 | EJ04810-02 | 0.0400 ppm |
| 2021-11-11 | EK02750-03 | 5.20 ppm |
| 2021-11-15 | EK03183-01 | ND |
| 2021-11-23 | EK04741-01 | 5.30 ppm |
| 2021-11-23 | EK04741-02 | ND |
| 2021-12-08 | EL02013-01 | 5.50 ppm |
| 2021-12-08 | EL02013-02 | ND |
| 2021-12-21 | EL04271-01 | 5.00 ppm |
| 2021-12-21 | EL04271-02 | ND |
| 2022-01-05 | FA01053-01 | 5.60 ppm |
| 2022-01-05 | FA01053-02 | 0.0500 ppm |
| 2022-01-19 | FA03676-01 | 5.20 ppm |
| 2022-01-19 | FA03676-02 | ND |
| 2022-02-01 | FB00452-01 | 5.50 ppm |
| 2022-02-01 | FB00452-02 | 0.0400 ppm |
| 2022-02-14 | FB02636-01 | 4.90 ppm |
| 2022-02-14 | FB02636-02 | 0.0300 ppm |
| 2022-03-01 | FC00420-01 | ND |
| 2022-03-01 | FC00420-03 | 5.30 ppm |
| 2022-03-14 | FC02689-01 | 5.20 ppm |
| 2022-03-14 | FC02689-02 | ND |
| 2022-03-29 | FC05148-01 | 5.20 ppm |
| 2022-03-29 | FC05148-02 | ND |
| 2022-04-11 | FD01955-01 | 5.30 ppm |
| 2022-04-11 | FD01955-02 | 0.170 ppm |
| 2022-04-25 | FD04440-01 | 5.10 ppm |
| 2022-04-25 | FD04440-02 | ND |
| 2022-05-10 | FE02315-01 | 4.70 ppm |
| 2022-05-10 | FE02315-02 | ND |
| 2022-05-24 | FE04850-01 | 5.40 ppm |
| 2022-05-24 | FE04850-02 | 0.210 ppm |
| 2022-06-07 | FF01644-01 | 4.30 ppm |
| 2022-06-07 | FF01644-02 | ND |
| 2022-06-21 | FF04256-01 | 6.20 ppm |
| 2022-06-21 | FF04256-02 | ND |
| 2022-07-06 | FG01019-01 | 5.50 ppm |
| 2022-07-06 | FG01019-02 | ND |
| 2022-07-19 | FG03657-01 | 5.70 ppm |
| 2022-07-19 | FG03657-02 | 0.0600 ppm |
| 2022-08-02 | FH00691-01 | 6.50 ppm |
| 2022-08-02 | FH00691-02 | ND |
| 2022-08-15 | FH03281-01 | 6.00 ppm |
| 2022-08-15 | FH03281-02 | 0.0500 ppm |
| 2022-09-12 | FI02259-01 | 5.00 ppm |
| 2022-09-12 | FI02259-02 | ND |
| 2022-09-26 | FI05016-01 | 5.80 ppm |
| 2022-09-26 | FI05016-02 | 0.120 ppm |
| 2022-10-13 | FJ02772-01 | 5.70 ppm |
| 2022-10-13 | FJ02772-02 | 0.240 ppm |
| 2022-10-25 | FJ04638-01 | 6.90 ppm |
| 2022-10-25 | FJ04638-02 | 0.210 ppm |
| 2022-11-09 | FK02197-01 | 5.10 ppm |
| 2022-11-09 | FK02197-02 | 0.180 ppm |
| 2022-11-22 | FK04383-01 | 0.240 ppm |
| 2022-11-22 | FK04383-03 | 5.00 ppm |
| 2022-12-06 | FL01202-01 | 4.50 ppm |
| 2022-12-06 | FL01202-02 | 0.220 ppm |
| 2022-12-21 | FL04376-01 | 4.80 ppm |
| 2022-12-21 | FL04376-02 | 0.230 ppm |
| 2023-01-03 | GA00430-01 | 0.250 ppm |
| 2023-01-03 | GA00430-03 | 4.60 ppm |
| 2023-01-17 | GA03017-01 | 4.70 ppm |
| 2023-01-17 | GA03017-02 | 0.210 ppm |
| 2023-02-08 | GB01743-01 | 0.210 ppm |
| 2023-02-08 | GB01743-03 | 4.70 ppm |
| 2023-03-06 | GC01064-01 | 4.20 ppm |
| 2023-03-06 | GC01064-02 | 0.250 ppm |
| 2023-03-21 | GC03818-01 | 4.60 ppm |
| 2023-03-21 | GC03818-02 | 0.250 ppm |
| 2023-04-03 | GD00481-01 | 5.20 ppm |
| 2023-04-03 | GD00481-02 | 0.260 ppm |
| 2023-04-19 | GD03536-01 | 4.70 ppm |
| 2023-04-19 | GD03536-02 | 0.260 ppm |
| 2023-05-01 | GE00297-01 | 0.260 ppm |
| 2023-05-01 | GE00297-03 | 5.10 ppm |
| 2023-05-17 | GE03669-01 | 5.50 ppm |
| 2023-05-17 | GE03669-02 | 0.170 ppm |
| 2023-06-01 | GF00295-01 | 5.70 ppm |
| 2023-06-01 | GF00295-02 | 0.130 ppm |
| 2023-06-15 | GF03131-01 | 0.170 ppm |
| 2023-06-15 | GF03131-03 | 4.60 ppm |
| 2023-06-28 | GF05181-01 | 4.10 ppm |
| 2023-06-28 | GF05181-02 | 0.0800 ppm |
| 2023-07-11 | GG01680-01 | 5.60 ppm |
| 2023-07-11 | GG01680-02 | 0.120 ppm |
| 2023-07-27 | GG05026-01 | 0.0600 ppm |
| 2023-07-27 | GG05026-03 | 4.60 ppm |
| 2023-08-08 | GH02084-01 | 5.50 ppm |
| 2023-08-08 | GH02084-02 | 0.180 ppm |
| 2023-08-22 | GH04740-01 | 4.40 ppm |
| 2023-08-22 | GH04740-02 | 0.150 ppm |
| 2023-09-07 | GI01299-01 | 4.70 ppm |
| 2023-09-07 | GI01299-02 | 0.120 ppm |
| 2023-09-19 | GI03367-01 | 5.00 ppm |
| 2023-09-19 | GI03367-02 | 0.250 ppm |
| 2023-10-10 | GJ02138-01 | 0.0700 ppm |
| 2023-10-10 | GJ02138-03 | 4.80 ppm |