A water meter is one of the most useful tools a St. Louis homeowner already owns, and most people never read it. It records every drop of water that passes into the house, which makes it a quiet way to catch a leak before it becomes a stained ceiling or a soggy basement floor. This guide explains how to find the meter, read it, and run a simple overnight check that shows whether water is moving when nothing should be running.
Finding the Meter
In many older St. Louis homes, the meter sits in the basement close to the front wall, where the main water line comes through the foundation. Newer houses and some rowhouses may keep it in a different spot, and some properties have an outdoor pit or a lidded box near the sidewalk or curb. If you cannot find it, follow the cold water supply pipe from where it enters the house back toward the street. The meter is usually on that line, often with a shutoff valve on each side.
Reading the Register
The main part of the meter is a numeric register that shows total use since the meter was installed. Many meters also have a small leak indicator, such as a triangle, star, or dial, that turns only while water is flowing through the line. Write down every digit on the register, including the ones that seem unimportant, because the lowest digits often change first during a leak. The layout varies by age and by provider, so look for a printed guide from your water provider if one came with your account.
The Overnight Check
The goal is a quiet house. Pick a time when nobody will need water for several hours, such as late evening, and follow these steps.
- Turn off every faucet, shower, and appliance that uses water, including the washing machine and dishwasher.
- Make sure no one flushes a toilet or runs water during the test.
- Write down the register reading and note whether the leak indicator is still.
- Leave the water alone overnight.
- Read the register again in the morning, before anyone runs a tap.
If the number moved and the leak indicator was turning while everything was off, water is leaving the system somewhere. If the numbers stayed put, the line is likely tight for that period.
Common Culprits in St. Louis Homes
Once a check shows movement, these are the usual suspects to review.
- A toilet tank flapper that does not seal, which can let water trickle into the bowl with no visible sign.
- A faucet cartridge or washer that drips slowly, often hidden under a sink.
- An irrigation system or outdoor spigot that was left on or has a valve that no longer closes fully.
- A water softener on a timer that regenerates at night. Regeneration draws water even though no tap is open, so check its schedule before you blame the pipes.
- A split or cracked pipe in an unheated garage, crawlspace, or exterior wall, which is a real risk during a hard freeze in the St. Louis area.
When you suspect one source, close the shutoff valve for that fixture or zone if you can, and repeat the overnight check. Narrowing the source one step at a time takes patience, but it is easier to manage at home than guessing.
When to Call for Help
If the indicator keeps turning after every fixture is off and every valve is closed, the leak is probably between the meter and the house, or on the street side of the meter. Those cases belong with your water provider, who can check the line on their side, or with a licensed plumber who can trace the house side. Bring your log, including the dates, times, readings, and which fixtures you shut off. A clear record saves time on the phone and on site.
Keeping a Simple Log
Keep the readings in a notebook or on a note taped near the meter. Record the date, the time, the register reading, and whether the leak indicator was moving. Repeat the check each season, especially before the first hard freeze and again in spring when outdoor watering begins. A baseline reading taken on a quiet night is the easiest way to notice a change later, because you will know what normal looks like for your household.