Nitrate is an inorganic compound containing nitrogen that can come from natural or man-made sources. Nitrates in water can cause severe illness in infants and domestic animals.
A plant nutrient and inorganic fertilizer, nitrate is found in septic systems, animal feed lots, agricultural fertilizers, manure, industrial wastewaters, sanitary landfills, and garbage dumps. High levels of nitrate can also indicate the presence of other pollutants, such as pesticides or bacteria.
Report: Addressing Nitrate in California’s Drinking Water
The March 2012 report by UC Davis, Addressing Nitrate in California’s Drinking Water, identified nitrate as one of the state’s most widespread groundwater contaminants, primarily resulting from the use of fertilizers containing nitrogen during agricultural production.
The California Department of Public Health (CDPH) has set the maximum contaminant level (MCL) for nitrate in drinking water at 45 milligrams per liter, and public water systems take action if this level is exceeded. However, at least 2.6 million people in the Central Valley and Salinas Valley rely on groundwater for drinking water. Many of the communities in the area are among the poorest in California and have limited resources for providing safe drinking water. The UC Davis report found that 96% of the nitrate contamination was from fertilizers used on cropland.
The report details major findings, looks at regulatory, funding and policy options; and lists several promising actions for dealing with the problem. Click here to read the report.
- Beneath the Tulare Basin: A Tour of Groundwater and the Many Paths of Water to Wells, by Thomas Harter
- Factsheet on Nitrate, by the California Department of Public Health
- Nitrate Webpage and Links, by the California Department of Public Health
- Coping with Nitrate Contamination, a multimedia presentation by California Watch
- Healthy Crops, Safe Water Program, University of California