Spring rain and snowmelt can push the river up in Lake St. Louis, and homes on lower ground or near the river bottom feel it first. If your home runs on a private well or a water softener, a flood is a good reason to slow down and check a few things before you return to normal water use.
Why low-lying wells need attention
Many wells in river-bottom ground draw from alluvial material close to the surface. When floodwater stands around a wellhead, surface water, silt, and whatever it carries can move toward the opening, especially if the cap, vent, or casing is cracked or missing. A well that has run well for years can still take on water it should not have after high water.
Homes on municipal supply are not exempt. Your tap water comes from a treated system, and the water provider's notices are the first thing to follow if a boil or use advisory is issued. Keep an eye on those notices during and after high water.
Check the wellhead first
Once the water has dropped and the ground is safe to walk, look at the well from a distance before you touch anything. Note cracks, loose caps, damaged vents, and silt packed against the casing. Look at the electrical box and wiring as well, since standing water can reach controls and connections. If anything looks wet, damaged, or buried, stop and call a licensed well contractor. Do not run the pump to test it while you are unsure about the wiring.
Test before you drink
A flood is a clear reason to test a private well, even if the water looked clear. A bacteria test for coliform and E. coli is the usual starting point. Use a certified lab, follow its sampling instructions exactly, and ask what the report means before you decide on next steps. Until results arrive, many homeowners use bottled water for drinking and cooking.
Consider testing for nitrates too, since runoff and septic influence can shift during high water. If your well is deep in bedrock, a radium test is worth discussing with the lab, particularly given the former Weldon Spring cleanup area in the wider service area, even though current municipal readings are within limits. A test describes the sample you collected on the day you collected it, so retest if conditions change.
Look at the softener after a flood
If your softener sits in a basement, garage, or utility room that took on water, do not assume it is fine. Check the control valve and any electrical connections for moisture or corrosion. Look inside the brine tank for silt, debris, or water that should not be there. Inspect the drain line and its outlet, since sediment can settle in low spots and slow flow. Salt that got wet may have clumped or partly dissolved, so check it before you add more.
Check the bypass valve position too. Leave it set the way you normally run the home until you know the system is dry and working. If the unit was under water, have it inspected before you restart it, and review its manual for guidance on flood exposure.
A simple flood checklist
- Follow any local water notices from your provider.
- Inspect the well cap, vent, casing, and wiring from a safe distance.
- Do not run a flooded pump or softener until a qualified person has checked it.
- Collect a bacteria sample using the lab's instructions, and use bottled water for drinking until you have results.
- Check the softener valve, brine tank, drain line, and salt for water damage.
- Write down dates, observations, and test results so you can compare them later.
Plan ahead for next season
Flood season is easier to handle when the setup is already sound. Keep records of your well construction, pump, and softener model, and note where each component sits relative to the ground. Keep the brine tank and salt off the floor where water can reach them. Review your wellhead and vent each year, especially before the wet months. A little attention in spring can save you from guessing later about what high water did to your home's water system.