Nitrate in well water: What you should know

What is a Nitrate? Nitrate (NO3) is a naturally occurring chemical made of nitrogen and oxygen. Nitrate is found in air, soil, water, and plants. Much of the nitrate in our environment comes from decomposition of plant and animal waste. People also add nitrate to the environment in the form of fertilizers. Natural levels of nitrate in Minnesota groundwater are usually quite low (less than 1 milligram per liter [mg/L]. 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 casings that are 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. Presence of nitrates in drinking water can cause a variety of long- and short-term effects.  Infants are at a particularly strong risk (for blue baby syndrome) as well as pregnant women, chronically ill and the elderly with some cases resulting in death.  If you have a high nitrate level you should consider testing your water for other contaminants.

Nitrate is measured in parts per million (ppm) or milligrams per liter (mg/L) (1mg/L =1 ppm).  Nitrate occurs naturally in surface and groundwater at concentrations up to 1-2 ppm and is not harmful at these levels.  The safe drinking water standard (also called maximum contaminant level or MCL) for nitrate is 10 ppm.  If your water has nitrate levels above 10 ppm you should switch to bottled water or another source of drinking water and seek treatment options.

Fortunately for Hubbard County residents our Soil and Water Conservation District (SWCD) provides well water testing for nitrate levels at no-charge. The first Friday of every month the SWD has a cooler located outside their office, from 9am to 2pm, for residents to drop off their well water samples.  The office is located at 603 Central Ave, Park Rapids.  Historically SWCD has set up test stations at local community events during the year but due to COVID19 that has not been happening.  Therefore, on the morning of April 1st three additional drop off stations have been created; they are:

  • Laporte Grocery Store, 20 Main St, Laporte 
  • Benedict Outpost, 34365 Hwy 38, Laporte
  • The Peddler, 23528 398th St, Laporte

 You can bring a half cup of water in a clean container or Ziploc-type bag. To get a good sample, allow the water to run five minutes before collecting. Homeowners with reverse osmosis or other nitrate removal systems should take two water samples—one before and one after the treatment process. This will determine if the nitrate removal system is working. Homeowners with just a water softener only need to take one sample, either before or after the water passes through the water softener.  Samples should be taken just prior to dropping off and at room temperature when arriving at the drop off point for testing. Each sample must have a label attached (or if in a Ziploc-type bag this information can be written on the bag using a permanent marker): 

Name, date, township, physical address of well, city, zip, county, email, phone, and depth of the well (if known) should be included with your sample. Slips will be available at the drop off sites or can be downloaded from our website at www.hubbardswcd.org .  Results will be sent directly to the homeowner via email after testing on    April 2, 2021.  For more information contact Annette Olson at 218-732-0121 ext. 105.