Know Your Environment. Protect Your Health.

Nitrate

City of Tacoma

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.

 

67

Samples

0

Samples exceeding legal limit (MCL)

56

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20181.90 ppm129ND - 4.60 ppm
20191.83 ppm1210ND - 4.95 ppm
2020N/A00N/A
20212.03 ppm1210ND - 4.71 ppm
20222.46 ppm1716ND - 3.74 ppm
20232.08 ppm1412ND - 4.06 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
2018-02-072.40 ppm
2018-03-124.20 ppm
2018-03-194.60 ppm
2018-04-11ND
2018-04-11ND
2018-06-122.80 ppm
2018-06-122.30 ppm
2018-06-212.00 ppm
2018-06-212.10 ppm
2018-07-192.40 ppm
2018-07-25ND
2018-10-180.0380 ppm
2019-01-022.53 ppm
2019-01-022.99 ppm
2019-01-022.51 ppm
2019-06-172.54 ppm
2019-06-172.54 ppm
2019-06-172.54 ppm
2019-06-24ND
2019-07-244.95 ppm
2019-10-230.370 ppm
2019-10-230.260 ppm
2019-12-030.750 ppm
2019-12-05ND
2021-06-2141362984.71 ppm
2021-06-2141363002.68 ppm
2021-06-2141362962.65 ppm
2021-06-2141316202.19 ppm
2021-06-2141362973.29 ppm
2021-06-3041370440.780 ppm
2021-06-3041370454.22 ppm
2021-06-304143413ND
2021-07-2141446710.360 ppm
2021-07-2141446720.220 ppm
2021-07-214159325ND
2021-07-2241446773.26 ppm
2022-02-0142389810.310 ppm
2022-07-1443184863.74 ppm
2022-08-0443315463.48 ppm
2022-09-1543711972.53 ppm
2022-10-0143616930.750 ppm
2022-10-1143616940.370 ppm
2022-10-114371889ND
2022-10-1143828490.750 ppm
2022-11-0843751883.45 ppm
2022-11-1543845332.77 ppm
2022-12-2743902392.30 ppm
2022-12-2743902363.66 ppm
2022-12-2744006883.55 ppm
2022-12-2744006883.55 ppm
2022-12-2744006883.55 ppm
2022-12-2744006883.55 ppm
2022-12-2744006883.55 ppm
2023-03-0344196643.49 ppm
2023-06-2044701673.68 ppm
2023-06-2044704022.55 ppm
2023-06-2744781563.61 ppm
2023-07-0544782182.70 ppm
2023-07-0544782162.21 ppm
2023-07-124491244ND
2023-07-1244996892.43 ppm
2023-07-1244996874.06 ppm
2023-07-1244861353.02 ppm
2023-10-204549137ND
2023-10-2045381210.360 ppm
2023-10-2045381220.710 ppm
2023-11-1545555600.270 ppm