Test the Waters is a campaign to encourage residents with private drinking water wells to have their water tested for nitrate, either by participating in one of the County’s mail-in sampling projects or by bringing a water sample to a water testing clinic.
The campaign is in response to the Targeted Townships project that found 30 percent of wells tested high for nitrate. See the complete results of the Targeted Townships project.
More testing in 2014
In order to better understand the extent of high-nitrate areas in Dakota County, the County and Minnesota Department of Agriculture will again partner to offer nitrate testing by mail to owners of private drinking water wells. Testing will be offered in the cities of Rosemount and Farmington and in Empire, Eureka, Greenvale, and Ravenna townships. The County will also offer free water testing clinics in high-nitrate areas.
The need to test well water
Nitrate, the most common form of groundwater contamination in the U.S., is a form of nitrogen. It can come from manure and septic systems, but high levels over large areas are generally the result of crop fertilizer. If plants don’t absorb all of the nitrogen in fertilizer, the surplus stabilizes as nitrate and leaches into groundwater and surface water supplies.
In infants younger than 6 months old, high nitrate can cause methemoglobinemia, or “blue baby” syndrome, which is a condition in which the baby’s blood doesn’t absorb enough oxygen. There is some evidence, but not conclusive, that high nitrate may be associated with other health risks for adults.
The Minnesota Department of Health considers drinking water high in nitrate with 10 milligrams per liter (10 parts per million).
It is strongly recommend that high nitrate water not be given to an infant under six months of age, either directly or in formula. Pregnant women should also avoid drinking well water that contains high levels of nitrate.
Water that has been treated (for example, through a properly maintained reverse osmosis system) is considered safe for adults and older children. Municipal supplies and commercially bottled water are regulated to meet the nitrate standard, and may be given to infants.
Nitrate is not removed from water by boiling, and a water softener is not effective at removing nitrate.