A water bill that jumps for no clear reason is almost always a leak you can't see. Here's the ten-minute meter test you can run yourself, the usual hiding spots, and when a smart leak sensor is actually worth the money.
Start with the meter test
Before you call anyone, you can confirm a leak in about ten minutes. Turn off every water fixture in the house and don't run the dishwasher, washing machine, or ice maker. Then find your water meter (usually near the street in a covered box) and write down the reading.
Wait an hour or two without using any water, then read the meter again. If the numbers moved, water is going somewhere it shouldn't. Many meters also have a small triangular or gear-shaped 'leak indicator' that spins when water is flowing. If it's turning with everything off, you have a leak.
The usual suspects
Most hidden leaks come from a short list of places. Before tearing anything open, it's worth ruling these out:
- A running toilet, where a worn flapper lets water trickle from the tank into the bowl day and night.
- Dripping faucets and worn supply lines under sinks.
- Outdoor spigots, irrigation lines, and hose bibs, especially after a hard freeze.
- The water heater, where the tank or a fitting has started to weep.
- A slab leak, where a supply line under the concrete foundation has failed.
- The main supply line between the meter and the house.
The silent budget-killer: the running toilet
A toilet that runs on and off is the single most common cause of a surprise bill, and it's the easiest to test. Put a few drops of food coloring in the tank (not the bowl) and wait fifteen minutes without flushing. If color shows up in the bowl, the flapper is leaking and needs replacing. It's a cheap part and an easy fix that can quietly cost you hundreds of gallons a day.
When the leak is hidden in a slab or wall
Some leaks never show up as a visible drip. With slab and behind-the-wall leaks, you're looking for indirect signs: a warm spot on the floor, the faint sound of running water when everything is off, unexplained mildew or a musty smell, paint or flooring that buckles, or a sudden drop in water pressure.
These are the ones worth bringing in equipment for. Rather than guessing and opening up drywall or concrete, we use acoustic and pressure tools to pinpoint the leak first, so the repair stays as small as possible.
Are smart leak detectors worth it?
Smart leak detection has gotten genuinely good. A basic battery sensor tucked behind the water heater or under a sink will sound an alarm and ping your phone the moment it gets wet, for a modest one-time cost. A whole-home monitor that clamps onto the main line goes further: it learns your normal usage and can automatically shut off the water if it sees a pipe burst while you're away.
Is it for everyone? Not necessarily. But if you travel often, own a second home, or have had water damage before, it can pay for itself in a single avoided flood, and some insurers offer a discount for having automatic shutoff installed. We're happy to tell you honestly whether it makes sense for your home or whether you'd do just as well with a basic sensor.
When to call us
If the meter test says you're losing water but you can't find the source, or you're seeing the warning signs of a slab leak, that's the point to bring in a plumber. We serve Chattanooga and the surrounding Tennessee Valley, Northwest Georgia, and the Sand Mountain communities of Northeast Alabama, and we go over the price with you before any work begins. Talk to a real plumber, not a call center, at 423-280-4171.