If you are buying a home in Lake St. Louis and the property draws from a private well, the water belongs in the inspection, not as an afterthought. Homes on municipal water receive a utility report each year, but a well has no such report unless someone creates one. This guide lists what to ask for and what to write down before you commit.
Start with the source question
Before anything else, confirm whether the house is on city water or a private well. Some properties near Lake St. Louis have a well that is no longer used for drinking, or one that serves only outdoor taps. Ask the seller for the well location, any well log that exists, and the date of the last service visit. Records filed when the well was drilled can also help, and your inspector can tell you what to look for on site.
What a well test should cover
A basic test for coliform bacteria and nitrate is a common starting point for a well, but the area has several concerns that a general panel may skip. Ask the lab exactly which parameters are included.
- Coliform bacteria and E. coli, which show whether surface contamination or a damaged well cap may be letting microbes into the water.
- Nitrate, which can come from agricultural runoff or a nearby septic system.
- Iron and manganese, which often cause staining on fixtures and laundry, particularly in wells drawing from river-bottom ground.
- Hydrogen sulfide, the source of a rotten-egg smell, more often found in deeper bedrock wells.
- Hardness and pH, which tell you what a softener would need to handle and whether the water tends to leave scale or corrode metal.
- Radium and other radionuclides, which occur naturally in some eastern Missouri bedrock aquifers.
Why radium belongs on the list
The former Weldon Spring cleanup site sits within the broader service area around Lake St. Louis, which is one reason homeowners ask about radium. Current municipal radium readings in the area are within limits, but those results describe the public supply, not a private well drawing from its own aquifer. A well's radium level depends on the surrounding rock and the depth of the well, so a neighbor's result does not transfer to your property. If the home has a well, ask whether radium has ever been tested and request the specific radium analysis rather than assuming a general panel covers it.
Questions to ask the seller
- Has the well been tested recently, and do you have the full lab report?
- Has the well cap or casing been repaired, and was the well disinfected afterward?
- Does the water smell, stain fixtures, or leave deposits in kettles or on faucets?
- Is there a softener, filter, or other treatment unit, and when was its media or salt last serviced?
- Where is the septic system and drain field relative to the well?
What to do with the results
A result that flags bacteria or nitrate is a reason to pause and talk with a licensed professional before closing, since the fix may involve the well structure, disinfection, or the septic layout. Staining results mainly affect fixtures and laundry, but they still shape how you will live with the water. Ask your inspector to note the well's condition in the report, and ask the seller whether they will address any findings before closing or adjust the price. Keep every report with your closing documents so the next owner starts with the same information.
Keep a record after you move in
Your first test becomes the baseline. Store it with your home file, retest on a schedule your well professional recommends, and retest after heavy rain, flooding, or any well work. Note the date, the lab, and which parameters were tested so future results can be compared on equal terms. A simple folder with reports, service receipts, and a short notes page is enough to start.