Introduction Nitrate is a common contaminant found in many wells in Minnesota. Too much nitrate in drinking water can cause serious health problems for young infants. This brochure provides a basic explanation of nitrate in wells and gives steps that you as a well owner can take to protect your family and visitors from illness. Nitrate is found in air, soil, water, and plants. Much of the nitrate in our environment comes from decomposition of plants and animal wastes.
People also add nitrate to the environment in the form of fertilizers.
However, where sources of nitrate such as fertilizers, animal wastes, or human sewage are concentrated near the ground surface, nitrate may seep down and contaminate the groundwater. Elevated nitrate levels in groundwater are often caused by run-off from barnyards or feedlots, excessive use of fertilizers, or septic systems. Wells most vulnerable to nitrate contamination include shallow wells, dug wells with casing which is not watertight, and wells with damaged, leaking casing or fittings. Nitrate contamination of a well is often regarded as a first sign of deteriorating groundwater quality. Too much nitrate in drinking water poses a risk to infants under six months of age.