If the water from your Wentzville tap or well fills a glass with bubbles, you are looking at one of two things: air that got into the plumbing, or gas that was already dissolved in the water and came out of solution as the pressure dropped. The two look similar at first, but they behave differently in the glass, and they point to different next steps. This guide walks through a simple glass test you can run at home before you spend money on a lab.
Wentzville homes draw water from a mix of sources, and private wells in the area can vary a lot from one property to the next. A well drawing from river-bottom ground can carry different gases than a deep bedrock well, so the same bubbling at the faucet may mean different things depending on your setup. Start by knowing what kind of supply you have.
Run the glass test
You need a clean clear glass, cold water from the faucet closest to the pressure tank or well line, and a few minutes of patience.
- Run the cold tap for a short time to clear the line, then fill the glass to the top and set it on a counter where no one will bump it.
- Watch the glass for the first few minutes. Bubbles that rise fast from the bottom and clear out of the glass quickly usually point to air that was trapped in the lines or the pressure tank.
- Look at the sides and the surface. Tiny bubbles that cling to the glass walls and keep forming over a longer stretch suggest gas coming out of solution as the water warms and loses pressure.
- Note whether the water looks clear when it first comes out. A cloudy or milky look that clears from the bottom up is often air. Water that stays cloudy or leaves a film is a different problem and calls for a different test.
- Repeat the test after the faucet has run a little longer, and again after the pump has been off for a while. Changes between runs tell you more than one glass alone.
Check the pressure tank and pump side first
Many bubbling complaints in Wentzville trace back to equipment, not to the aquifer. A pressure tank with a failed bladder can push air into the line, and a waterlogged tank that has lost its air cushion can send surges of air and water through the faucets. Both are common enough that they should be ruled out before you assume the water itself is changing.
Look for these signs: spurting at the faucet right after the pump starts, a pump that cycles more often than it used to, or air coming out only at certain faucets. Keep your notes handy. A licensed well contractor or pump service person can check the tank and its air charge, and you can ask them to walk you through what they find. Do not open or adjust pressure equipment if you are not sure how it works.
When the smell is part of the picture
Some bubbling wells also carry a rotten-egg smell, which often comes from dissolved hydrogen sulfide. That smell can show up in both hot and cold lines, or mainly in the hot line, so compare the two at the same faucet before drawing conclusions. The glass test cannot tell you what the gas is. A lab test can, and a lab can also measure iron and other items that often travel with sulfur in river-bottom wells.
If the smell is more like gas than sulfur, leave the area, ventilate it, and call your local fire department before anything else. Testing can wait until the air is safe.
What to ask the lab for
A standard bacteria test does not measure dissolved gases, so do not assume your sample results cover them. When you call a lab, ask whether it can run a dissolved gas or sulfide test, and confirm the container and handling it requires. If your well sits near a gas line or the bubbles smell of gas, say so when you call so the lab can advise on the right method.
Ask the lab to note the sample time and whether the sample was drawn before or after the pressure tank. That detail matters because gas can escape while water sits in a container. Keep the bottle cool and deliver it promptly, following the lab's directions.
Keep a short bubble log
Write down the date, the faucet you tested, whether the water was clear when first drawn, when bubbles appeared, and what the pump was doing. Note any heavy rain, since storm events can change how a shallow well behaves. Bring the log to your tests. Over a few weeks, a pattern usually emerges: bubbles that appear every time the pump starts point to equipment, while bubbles that linger in the glass point to gas in the water.
Next steps for Wentzville homeowners
- Run the glass test at two faucets, one near the pressure tank and one farther away.
- Check the tank and pump side with a qualified person before you assume the water changed.
- Compare hot and cold water at the same faucet for smell.
- Ask a lab about dissolved gas or sulfide tests if the glass test points to gas.
- Keep the bubble log and bring it to the lab and to any service call.