Is my well water safe to drink after it floods?

We had one of the wettest springs on record in Dane County, and the trend continues this summer. So far this year, we’ve seen 10+ inches above our normal rainfall. As a result, you’ve likely noticed the high-water levels on local lakes and rivers and flash flood warnings after it rains. If you own a private well and your area recently flooded, your well water may be unsafe. Keep reading to learn how to find out and what to do if it is.

Flood waters can hold dangerous bacteria and can make your water unsafe to use.

If you use a private well for your water, you are responsible for testing and maintaining your well. It is recommended that you test your water every year, but you may need to test sooner if there has been flooding. Flood waters can carry all sorts of contaminants, including sewage, bacteria and viruses, fertilizers, heavy metals, chemicals, and more. Your well water might be unsafe if:

• Flood waters touched or ran over the top of your well.
• You notice changes in taste, smell, or color of your water.
• You have a shallow well and live near areas that were flooded.

If you suspect your well has been affected by flooding use safe water until your well is disinfected.

After a flood, do not use your well water for drinking, cooking, or bathing until it has been tested and is considered safe or it is properly disinfected. Instead, use bottled water, tap water that you boiled for one minute, or water from a well that was not flooded.

Once your well is no longer touching flood water, you can disinfect it. We recommend using a licensed well driller or pump installer with the right expertise and equipment to disinfect your well.

The disinfection process can take as long as a week. It is crucial you allow the proper amount of time for this process to work and continue to use safe water during this time.

After a week, it’s time to test a water sample from your well to see if bacteria are present. We can help you decide what type of test you need based on your specific situation and go over the costs. Just email us or call 608-243-0357. Disinfecting can be tricky, so make sure you don’t skip this step! If your test reveals bacteria are still present, continue to use safe water and reach out to us. We are happy to go over your next steps.

Not sure if your well was impacted? No matter what, we recommend annual well testing!

It’s good practice to test your well water every year for contaminants including coliform, bacteria, and nitrates. Certain factors about your plumbing may indicate a need for additional testing to check for lead and other metals. If you need more information, call our lab at 608-243-0357. We can recommend other tests depending on your well's location, age, etc.