Greg Brenneman
Agricultural Engineering Field Specialist
Iowa State University Extension & Outreach
Whether you moved to the country and own a well for the first time, or you've relied upon a well most your life, chances are good that you don't have an owner's manual that goes with your well. Thousands of people across the U.S. utilize private wells for drinking water for themselves or their livestock. Maintenance of these wells is critical to keeping wells functioning properly.
What do you know about your well? How deep is it? What is its capacity? How old is it? What depth is the pump? How deep is the casing and is the water safe to drink? Answers to many of these questions may take the help of the previous owner or a well contractor.
Usually, the best information will come from the contractor who drilled the well. They may have records on the well depth, draw down during pumping, casing depth, water yield, etc. You can ask the previous owner if he or she knows who the contractor was. Another place to check is county health departments. In recent years they have issued permits and kept records of well construction. The Iowa Geological Survey has a database of more than 55,000 wells in Iowa. This can be accessed on the internet at https://www.iihr.uiowa.edu/igs/geosam/map and click on the county you are interested in. Then just zoom into your location and see all of the wells that the Iowa Geological Survey has data on.
If no information can be found, a new well contractor can measure the well and water depth, and perform a pumping test to measure the yield and draw down.
While all of this information is good to have, especially if you will be increasing your water use for livestock or irrigation, it is also important to test the safety of the water for home use. There is no one test that tells you if the water is safe to drink. Unless a specific contamination problem is suspected (such as a chemical spill), it is normally recommended to test private wells for coliform bacteria and nitrate as general indicators of the safety. These low-cost tests will tell you if your water system has been contaminated by surface or shallow groundwater getting into the well.
Well water sampling kits can be ordered from the University of Iowa Hygienic Laboratory at 1-800-421-4692. or online at http://www.shl.uiowa.edu/env/privatewell/ordering.xml.
Most of Iowa's counties participate in the Grants-to-Counties Well Program. The Grants-to-Counties program will provide free water sampling and analysis to qualifying private drinking water systems. To find out if your county participates in the Grants-to-County Well Program or to arrange sampling of your water system, please refer to the list of County Environmental Health Sanitarians and contact the Sanitarian's office in the county where the well is located.
Resources
For more detailed information on wells, well construction, and water testing check out these publications from your Extension office or online.
- Good Wells for Safe Water - PM-840
- Coping with Contaminated Wells - PM-1329
- Sampling Your Drinking Water - PM-1335