Signs of a hidden leak
- A water bill that jumps with no change in use.
- The meter moving when nothing is running.
- The sound of running water when the house is quiet.
- Warm spots on a slab floor, or damp, stained or bubbling drywall.
- A musty smell, or mold in a cabinet or closet.
- A soggy patch in the yard between the meter and the house.
- Low water pressure that came on suddenly.
The meter test, step by step
- Turn off everything that uses water: taps, dishwasher, washer, ice maker, irrigation.
- Find the meter. Greenville Water meters are outside, usually near the street in the right of way. Lift the lid carefully.
- Note the reading or watch the small leak indicator (a triangle or star on many meters).
- Wait 15 minutes without using any water, then check again.
- If it moved, close the main shut-off at the house and check again. If the meter stops, the leak is inside the house. If it keeps moving, the leak is in the service line between the meter and the house.
Meter moving? Have a plumber find the leak
Check the toilets first
A running toilet is the most common hidden leak and the cheapest to fix. Put a few drops of food coloring in the tank and don't flush for 15 minutes. If color shows up in the bowl, the flapper is leaking. A new flapper is a small part you can often replace yourself.
How plumbers find leaks
| Method | What it does |
|---|---|
| Pressure testing | Isolates sections of pipe to show which one is losing pressure |
| Acoustic listening | Picks up the sound of water escaping through walls, floors or soil |
| Thermal imaging | Shows warm or cool spots from hot or cold water lines leaking behind walls or under slabs |
| Moisture meters | Measures dampness in drywall, wood and flooring to trace the source |
| Line locating | Traces the path of buried water lines so only the right spot is dug |
Slab leaks
Many newer Upstate homes, especially in the 2000s and 2010s subdivisions around Greer, Simpsonville and Fountain Inn, sit on concrete slabs, with water lines under the floor. A leak there shows up as a warm floor spot, a sound of running water, or a high bill. Repair options are to break the slab and fix the pipe, or to reroute the line through walls or the attic. National figures put slab leak repair at about $1,000–$4,000 typically (Fixr, 2025).
Your side or the utility's?
Greenville Water maintains the line up to the outlet side of the meter; from there to the house is yours. A leak in the street or the meter box is the utility's to check first: (864) 241-6000. Our who-owns guide has the details, and our water line repair page covers fixing the service line.
Leak detection and repair costs
| Job | Typical range | Source |
|---|---|---|
| Leak detection | $200–$500 | A Greenville plumbing company's published range, 2026 |
| Leaking pipe repair | $105–$315 | Today's Homeowner, Greer SC, Feb 2025 |
| Slab leak repair | $1,000–$4,000 typical | Fixr national, May 2025 |
| Main water line repair | $397–$3,177 | Today's Homeowner, Greer SC, Feb 2025 |
Insurance and your water bill
- Homeowner's policies often cover sudden water damage but not slow leaks or the pipe repair itself. Photograph the damage and keep the plumber's invoice.
- Ask your water utility whether it offers any bill adjustment after a repaired leak, and what proof it needs.
Ready to find the leak?
Leak detection questions
How do I know if I have a hidden water leak?
Turn off all water use and watch the meter for 15 minutes. If it moves, water is leaking somewhere. A high bill, the sound of running water, and damp spots are other signs.
How much does leak detection cost in the Greenville area?
About $200–$500 for professional detection, based on an Upstate company's published range. The repair is usually priced separately once the leak is found.
Can a plumber find a leak without tearing out walls?
Usually, yes. Acoustic listening, thermal imaging and pressure testing narrow it down to a small area, so only a small opening is needed for the repair.
What does a slab leak feel like?
Often a warm spot on the floor from a leaking hot water line, along with the sound of running water and a higher bill. Cracks or damp flooring can also appear.
How can I tell if my toilet is leaking?
Add a few drops of food coloring to the tank and wait 15 minutes without flushing. Color in the bowl means the flapper is leaking.
Is a leak between the meter and my house my responsibility?
Yes. Greenville Water maintains the line up to the outlet side of the meter; the service line from the meter to the house belongs to the homeowner.
Sources
- Greenville Water: customer service page (line responsibility, meter location, emergency number). greenvillewater.com
- Upstate plumbing company published leak detection range (2026); Today's Homeowner (Greer, SC, Feb 2025); Fixr slab leak repair costs (May 2025).
- Census ACS 2020–2024 5-year estimates (housing age).
Page history
October 2026: first published.