Costs & planning

High water bill? How to find a hidden leak

Updated 2026-09-30

Short answer

Turn off every fixture and watch the meter's leak indicator for 15 minutes. If it moves, put dye in each toilet tank, check the water heater and irrigation, then call for leak detection if you still can't find it.

Step 1: The meter test

Turn off every faucet, appliance, ice maker and irrigation zone. Find the meter, often in a pit near the street in Colorado or in the basement, and watch the small leak indicator. Any movement means water is going somewhere.

Step 2: Usual suspects

Toilets: a few drops of food coloring in the tank; color in the bowl means a flapper leak
Water heater relief valve dripping into a drain
Irrigation valves or a cracked backflow device
Outdoor hose bibs that split over winter
Water softener stuck in regeneration

Step 3: Isolate the house

Close the main shutoff in the house and watch the meter again. If it still moves, the leak is in the service line between the meter and the house.

What leak detection involves

If simple checks don't find it, a plumber isolates the system: house versus service line, hot versus cold, and individual branches. Acoustic equipment, thermal cameras and moisture meters then narrow the leak to a small spot.

Only that spot is opened for repair. Keep the invoice; many water providers offer a one-time leak adjustment with proof of repair.

Isolation tests
Acoustic and thermal pinpointing
Targeted repair
Invoice for a bill adjustment

When to call a plumber

Call if the problem keeps coming back, if water is reaching walls, ceilings or electrical areas, or if any step above involves gas, a torch or opening a sewer line. A licensed plumber handles leak detection and will explain the cause before starting.

Questions

Will my water utility adjust a bill for a leak?

Many Front Range providers offer a one-time leak adjustment with proof of repair. Ask your provider and keep the plumber's invoice.

Can a toilet leak really raise my bill that much?

Yes. A flapper that never seals can run water constantly, which can show up clearly on a monthly bill.

This guide is general information for Colorado homeowners, not a substitute for an on-site diagnosis. Local codes vary; your plumber and building department have the final word.