Assume all flood water is contaminated and KEEP CHILDREN AND ANIMALS OUT OF THE WATER. Do not swim or bathe in rivers, streams, creeks or lakes in flooded areas!
Floods along Wisconsin rivers and streams can pose a potential health danger for private well users if wells are flooded. Well owners whose wells become flooded need to have the well tested before resuming use of the water. Floodwaters can contain bacteria and waste contaminants that threaten water supplies. Wells located in pits and basements are especially susceptible to such contamination. Any water supply system which has been overtopped by flood waters should be thoroughly disinfected and then tested to determine water safety. This work is best performed by licensed well drillers or pump installers. Wells should be disinfected with a strong chlorine solution or chlorine tablets. The chlorine must come into direct contact with all interior surfaces of the well, from top to bottom and throughout the distribution plumbing. The solution should remain in the system for 24 hours and then flushed from the system. Then a water sample can be collected and submitted for bacteriological testing. Information about how to chlorinate your well is available from DNR customer service centers and on the DNR website at:
The Winnebago County Health Department may be able to provide sample kits for testing wells that have been flooded. Contact us at 920-232-3000.