The floods that have swamped most of Missouri have rendered a lot of well water undrinkable. If your well has been submerged in floodwater, Daryl Brock with the Department of Health and Senior Services says you should not use the water.
"The best precaution is not to drink the water until they’ve flushed out the well some," says Brock, "If they note that they’re seeing some coloring in the water, they would probably want to then disinfect their wells."
Your well water may be unsafe even if it is not submerged in floodwaters. Brock says that while all wells under floodwaters are not safe for drinking, wells that are near flooded areas may be affected also, by water seeping into underground sources that feed the well.
Brock advises citizens to disinfect their wells after the flooding recedes with a solution of half chlorine and half water; then have the water tested by your local health department.