Thousands of water wells are located within flooded areas of the Midwest that could be contaminated with E. coli, according to the National Ground Water Association.
The Association says the number of wells impacted could be substantial because a large portion of the Midwest affected by flooding relies on groundwater for rural and small municipal water supply. Household, farm, and small business wells could be standing in water for several days, raising the potential for contamination.
While the exact number of wells possibly affected by contaminated floodwater cannot be readily counted, Census Bureau data show over one million wells in 300 counties impacted by flooding. This estimate includes counties flooded in Illinois, Indiana, Iowa, Kansas, Kentucky, Minnesota, Missouri, Nebraska, South Dakota, and Wisconsin during the March 2019 winter storm. Following a flood, disinfection and wellhead repair may be common needs among well owners.
Well relocation and elevation may also be useful and protective. The association says well owners should continue to monitor and test their systems.