Every diagnostic path for a hidden leak starts at the water meter. It is the one place that measures all water entering your home, so it answers the most basic question first: is water leaving the system when nothing is running? Here is how to get that answer yourself.
Where is my water meter?
In most Flower Mound neighborhoods, the water meter sits in a ground-level box near the street or sidewalk, usually at the front of the property near the property line. Look for a rectangular metal or plastic lid, sometimes marked "water" or "meter."
Lift the lid carefully. You may need a screwdriver or a meter key to pry it open, and the box sometimes contains dirt, insects, or standing water. Clear debris gently so you can see the meter face. If the box is full of water, bail or sponge it out; a flooded box can hide the dial you need to read.
If you cannot find the box, check your water utility's website for guidance or call them. They can usually describe the typical location for your neighborhood.
How do I prepare for the test?
The test only works if no water is being used anywhere in the home during the check. Before you open the meter box:
- Turn off all faucets, inside and out.
- Make sure the dishwasher, washing machine, and any other water-using appliance are off and not mid-cycle.
- Turn off the irrigation controller, or confirm no zone is scheduled to run during your test window.
- Tell everyone in the house not to flush, run water, or use any appliance until you say so.
Ice makers and water softeners can draw water on their own. If your softener is mid-regeneration, wait until it finishes. The goal is a house where every legitimate water use is paused.
What is the leak indicator, and how do I read it?
Most residential meters have a small leak indicator on the dial: a tiny triangle, star, or gear that spins with even very small flows. It is designed to catch leaks too slow to move the main dial noticeably.
With everything in the house off, watch the indicator for one to two minutes:
- Indicator is spinning: water is flowing through the meter. Something is using or losing water. You have a leak (or something is still running; double-check the house).
- Indicator is completely still: no water is currently moving through the meter. A significant active leak is unlikely at this moment.
The indicator is sensitive enough to catch a slowly running toilet, so a spinning triangle does not automatically mean a slab leak. It means water is going somewhere, and the next steps narrow down where.
How do I run the two-hour meter test?
The leak indicator catches active flows, but a very slow leak might not spin it visibly. The two-hour test catches those:
- With everything off, write down the exact meter reading, including all digits.
- Do not use any water for two hours. No flushing, no faucets, no appliances, no irrigation.
- After two hours, read the meter again.
- Compare. If the number is higher, water moved through the meter during those two hours, and you have a slow leak.
Pick a window when the house is empty or everyone is asleep to make the no-water rule easy. Overnight works well for many households.
What do the results mean?
Meter moves, indicator spins fast: A substantial leak or a fixture running continuously. Check toilets first, then listen for running water. If toilets are fine, the leak is in the plumbing system itself.
Meter moves slowly over two hours: A slow leak. Could be a toilet flapper, a dripping fixture, a softener issue, or a pinhole in a pipe. Work through the checks in our high water bill guide to rule out fixtures and systems.
Meter does not move at all: Your plumbing is holding water normally right now. If your bill was high anyway, the cause was likely a one-time event, an irrigation schedule issue, or a meter reading correction. Keep an eye on the next bill.
Meter moves even with the main house valve shut off: This is a useful extra check. Shut off the main valve where water enters the house. If the meter keeps moving, the leak is in the service line between the meter and the house, in the yard. If it stops, the leak is inside the home's plumbing.
What are my next steps after a positive test?
If the meter confirms water loss, narrow it down before calling:
- Check every toilet with the food-coloring test described in our high water bill guide.
- Walk the irrigation zones and look for broken heads or soggy spots.
- Check the water softener and any RO system for continuous discharge.
- Look and listen for the slab leak signs: warm floors, running-water sounds, new cracks, musty smells. Full details in our slab leak signs guide.
If you have ruled out fixtures and systems and the meter still moves, it is time for professional leak detection. Bring your meter readings and notes about what you checked; that information helps the specialist start in the right place.