Is it Safe to Drink?

By Sunni Heikes-Knapton 

With spring upon us, many private well owners are seeing changes taking place with the water in our subsurface aquifers.  As snowmelt occurs in the upper elevations, and streams and rivers are experiencing historically high flows, much of this surface water is finding its way to the groundwater network. But thinking about the potential dangers that might be coming with that water is important for every private well owner to consider. Potential contaminants could be a risk to anyone who consumes well water. 

The surface water and ground water connections in our area are a good reminder that annually testing your well is an important responsibility to ensure that your water is free from dangerous levels of bacteria and nutrients.   It is recommended that household well owners test their water at least annually for any major potential contaminants, and more frequently if: 

• There is a change in the taste, odor, or appearance of the well water, or if a problem occurs such as a broken well cap, inundation by floodwaters, or a new contamination source

• The well has a history of bacterial contamination

• The septic system has recently malfunctioned

• Family members or house guests have recurrent incidents of gastrointestinal illness

• An infant is living in the home

• One wishes to monitor the efficiency and performance of home water treatment equipment.

Test kits are available at the Madison Conservation District office, as part of a state wide program managed by Montana State University Extension. Known as The Well Educated Program, the effort provides information in many formats on how well owners can understand, monitor, and manage their wells and well water health.  

As explained at the Montana Well Educated Program website, “People who are on municipal water supplies have a vast set of people and resources in place to insure their water meets drinking water quality standards. Private well water supplies are not monitored by government or municipal agencies. This means the well owner must take responsibility for monitoring well water quality.”  

There are many parameters that one might consider when doing an annual test, with the most important being those that pose a health risk to consumers. The Well Educated website provides a good set of questions to ask to help determine which analysis should be run on your sample, with most situations encouraging testing for bacteria and nitrates.  

Total coliform is the most commonly used indicator of bacterial contamination. The presence of coliform bacteria is an “indicator” of a well’s possible contamination from human or animal wastes. The presence of coliform bacteria in well water can be a harbinger of worsening water quality. In some cases, more specific tests for fecal contamination, such as E. coli, may be used.

High levels of nitrate in well water present a health concern and can also indicate the presence of other contaminants, such as bacteria and pesticides. Drinking large amounts of water with nitrates is particularly threatening to infants (for example, when mixed in formula). Common sources of nitrate to well water are fertilizers, septic systems, animal manure, and leaking sewer lines. Nitrate also occurs naturally from the breakdown of nitrogen compounds in soils and rocks.

Arsenic is an example of a water-quality concern that can be seen in wells in the Madison Valley.  Arsenic occurs in water that comes into contact with some types of rocks and soils common in Yellowstone National Park and some streams in our area are also known to have high Arsenic levels. 

Indicators of a dirty well include cloudy water, low water flow into the well, or taste or odor problems. If these problems persist, or positive bacteria results are reported from well testing, then it is recommended that a qualified water well system professional should inspect the well. 

Test kits are available for free from the Madison Conservation District office in Ennis, with the well owner then selecting their own parameters and paying for own analysis.  For more information, contact us at 682-7289.