CRAWFORD AND VERNON COUNTIES - On Thursday, Jan. 9, farmers and residents of two watersheds in the Kickapoo River Valley will gather to hear results of well testing. The samples in the West Fork Kickapoo and Tainter Creek Watersheds were taken in November. Scientists from the UW-Stevens Point Center for Watershed Science and Education (CWSE) will travel to the area to present the results.
In the West Fork Kickapoo Watershed, the November sampling was the first systematically undertaken sampling. A total of 50 samples were drawn. The West Fork Neighbors will gather at Nature Nooks Retreat, S4878 County Road S, Viroqua, WI 54665, on Thursday, Jan. 9, at 6 p.m. to hear the test results. The specifics of individual well test results will not be shared.
The sampling in the Tainter Creek Watershed is the second annual sampling taken, with the first having occurred in November of 2018. The presentation on the November 2019 sampling results will take place on Thursday, Jan. 9, at 7:30 p.m. at the Franklin Town Hall in Liberty Pole.
In the Tainter Creek Watershed in 2018, 44 wells were sampled – 26 in Vernon County and 18 in Crawford County. In 2019 39 samples were taken – 21 in Vernon and 18 in Crawford. Of the total 39 wells sampled in 2019, 10 were repeats from 2018, and 29 were wells not tested in 2018. The Watershed Council allowed people who had received concerning results in 2018 to re-test in 2019.
Tainter 2018 results
In the 2018 sampling in the Tainter Creek Watershed, coliform bacteria was shown to be present in 25 percent of the wells tested. E.coli, which is a member of the coliform bacteria group, was not present in any of the samples that tested high for coliform. E.coli comes either from animal or human waste and is considered an indicator that a pathway exists for contaminants from the surface to enter the well water.
“If there had been E.coli in any of the samples, we would have recommended stopping use immediately and re-testing,” CWSE’s Jessica Haucke explained.
“Detecting total coliform, is an indicator that there is cause for concern,” Haucke elaborated. “We encourage well owners who get a positive result for coliform to become sleuths to try and identify how the bacteria are getting into their water and what the source might be. An ongoing program of testing may be necessary to evaluate the success of any remediation efforts.”
Dr. Paul McGinley of CWSE described nitrate as the biggest cause for concern from the testing results. He was also quick to say, that the problem is widespread throughout the state.
In the 2018 sampling in the Tainter Creek Watershed, results in the 2.1 to 5.0 milligrams per liter (mg/L) range occurred in 11 percent of the samples; 39 percent were in the 5.1 to 10.0 mg/L range; and a concerning 23 percent were in the 10.1 to 20.0 mg/L range. Any result above 2 mg/L is considered to be above the naturally occurring level of nitrate.
Wells that test over 10 mg/L nitrate are not considered safe for women who are or may become pregnant, and infants.
In response to a question about whether the test results showed clusters of nitrates, Dr. McGinley answered that there was a cluster of high nitrate concentrations in the northern part of the watershed. He emphasized that the best opportunity to capture nitrate before it reaches groundwater is in the plant root layer of the soil. This, he says, is one of the most compelling reasons to plant cover crops and maintain a continuous root structure in the soil throughout the year.
For residents whose wells tested high, Haucke listed the solution, and also short-term strategies.
“The solution is to eliminate the source of the nitrate,” Haucke said. “In the short term, residents with high nitrates in their well water can explore changing the depth of their well; they can carry or buy water; or they can install a treatment system such as reverse osmosis, distillation, or an anion exchange system.”
In answer to a question about how often people with no nitrates showing up in their well water should retest, Haucke responded, “we recommend testing every year or two, and one test alone will not show a trend or demonstrate potential seasonal variations.”
Tainter Creek Watershed Council farmer Brian McCulloh queried McGinley about whether there is any longitudinal data available for the area about groundwater quality.
“What our group wanted to do was to establish a baseline for groundwater quality in the watershed,” McCulloh said. “If we don’t have any historical data to compare it to, then we are really just getting started.”
McGinley answered McCulloh’s question by explaining that public water systems are highly regulated, required to test regularly, and would be the best source of any historical data. He said examples of public water systems in the area for which there might be results would be churches, taverns, and other public places. Private well owners are not required to test their wells, and not required to share their results if they do have them tested.
McCulloh pointed out that even decomposing plant material on the surface of the soil has potential to produce nitrate.
McGinley responded that decomposing plant material is always a source of nitrate on any land. When that occurs in the spring and fall, and if there are less roots in the soil, then it becomes more likely that the nitrate will make it into the groundwater.
Vernon County Conservationist Ben Wojahn added that the best way to prevent nitrate from getting into groundwater is to grow cover crops, and to use a Nutrient Management Plan to make sure that you are using the right amount of fertilizer on crops.
Bruce Ristow reported that the sample taken from the Bathtub Spring in Star Valley tested positive for coliform. He was quick to point out that it is just basically a tube protruding from a hillside that allows the water to run into an old bathtub. The well is not deep, and does not have a casing.
Another resident asked if extremely wet years, like the one we just had in 2018, have potential to increase the amount of water percolating into the groundwater, carrying nutrients from the surface with it.
“Wetter years can result in more water entering groundwater,” McGinley answered. “Water percolates into the ground, but then moves into the groundwater relatively slowly, so only some of the water in your well today is likely to be from recent rain events.”
McGinley went on to elaborate that the Fall of 2018 weather and floods, especially occurring as they did at the time of year when most of the crops were still in the ground, means that they were probably not a major factor in the nitrate results from the recent testing. He explained that the one exception would be in the immediate vicinity of a sinkhole or thin soils, where water can travel through the soil layer and penetrate into the fractured bedrock more quickly.
Viroqua resident Alicia Leinberger asked why the results didn’t contain a result for phosphorous.
“Our testing equipment does give a result for phosphorous,” Haucke responded. “But since phosphorous is not considered a human pathogen, we don’t include it in the testing results.”McGinley said that the average amount of phosphorous in groundwater is very small, about 0.02 mg/L. This, he explained, is much lower than the results that are found in surface water.