Nitrate

Dennis Water District

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.

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Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2014	0.977 ppm	10	8	ND - 2.30 ppm
2015	0.873 ppm	12	10	ND - 1.90 ppm
2016	0.761 ppm	9	8	ND - 1.90 ppm
2017	0.633 ppm	9	7	ND - 1.60 ppm
2018	0.966 ppm	9	9	0.0700 ppm - 2.40 ppm
2019	0.716 ppm	9	7	ND - 1.70 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	Result
2014-03-17	0.940 ppm
2014-03-17	ND
2014-03-17	2.20 ppm
2014-03-17	1.50 ppm
2014-03-17	0.690 ppm
2014-03-17	ND
2014-03-17	0.620 ppm
2014-03-17	0.910 ppm
2014-03-17	0.610 ppm
2014-03-17	2.30 ppm
2015-03-11	0.570 ppm
2015-03-11	1.10 ppm
2015-03-11	ND
2015-03-11	0.920 ppm
2015-03-11	ND
2015-03-11	1.000 ppm
2015-03-11	1.90 ppm
2015-03-11	1.70 ppm
2015-03-11	1.10 ppm
2015-05-19	0.190 ppm
2015-07-14	0.490 ppm
2015-07-14	1.50 ppm
2016-03-10	0.1000 ppm
2016-03-10	1.000 ppm
2016-03-10	0.560 ppm
2016-03-10	1.50 ppm
2016-04-26	0.170 ppm
2016-04-26	ND
2016-04-26	1.90 ppm
2016-04-26	0.900 ppm
2016-06-09	0.720 ppm
2017-02-02	0.120 ppm
2017-02-02	1.60 ppm
2017-02-02	0.580 ppm
2017-05-19	1.50 ppm
2017-05-19	0.740 ppm
2017-05-19	ND
2017-06-20	0.990 ppm
2017-06-20	ND
2017-06-23	0.170 ppm
2018-06-04	2.40 ppm
2018-06-04	1.40 ppm
2018-06-04	0.410 ppm
2018-06-04	0.1000 ppm
2018-06-04	0.760 ppm
2018-06-04	0.0700 ppm
2018-06-04	0.750 ppm
2018-06-04	1.60 ppm
2018-06-20	1.20 ppm
2019-05-03	ND
2019-05-03	1.70 ppm
2019-05-03	0.650 ppm
2019-05-03	0.620 ppm
2019-05-03	ND
2019-05-03	1.70 ppm
2019-05-03	0.610 ppm
2019-05-03	0.840 ppm
2019-05-03	0.320 ppm