It happens. You open your water bill expecting the usual $80-$150 and see $412 instead. Las Vegas Valley Water District doesn't make billing mistakes that big — if the bill spiked, you almost certainly have a leak somewhere. Here's how we investigate it, including what you can check yourself before calling.
The 30-second mental model
Every drop of water that hits your meter goes one of three places: down a drain (used water), out an irrigation line (landscaping), or into a leak. If your usage spiked but your habits didn't change, you have a leak. The question is just WHERE.
Step 1: Toilets first (this is the #1 cause)
A leaking toilet flapper can waste 200 gallons per day silently — no sound, no visible drip. The water just keeps refilling forever. Test every toilet:
- Drop a few drops of food coloring (or a dye tab) into the tank.
- Wait 15-20 minutes WITHOUT flushing.
- Check the bowl. If you see any color, your flapper is leaking.
Flapper kits are $10 at any hardware store. This is the cheapest first thing to rule out.
Step 2: Watch the meter
Find your water meter — usually a concrete box in the front yard near the curb. Open the lid. Look at the dial.
- Shut off every water-using fixture in your house: sinks off, ice maker off, washer not running, dishwasher off, irrigation off.
- Watch the meter for 2-3 minutes.
- If the small triangle/dial is still spinning, you have a leak somewhere between the meter and a fixture.
Step 3: Isolate to inside or outside
If the meter is moving, shut off your main house valve (usually in the front yard or by the garage). Watch the meter again.
- If the meter STOPS: the leak is inside the house (slab leak, pipe leak, hidden toilet, etc.)
- If the meter STILL MOVES: the leak is between the meter and the house valve — that's your mainline service line. Common in Vegas homes 25+ years old.
Step 4: Irrigation check
If you don't have a separate irrigation meter, your sprinkler system shares the main supply. Check for:
- Soggy or unusually green patches in the yard
- Water pooling near valve boxes
- Buried drip lines that won't pressurize evenly when tested
Buried irrigation cracks are sneaky — they can leak underground for months without any visible surface symptom.
Step 5: Pool check (if you have one)
Pool leaks are HUGE water wasters — 100-300 gallons per day is typical. Do the bucket test:
- Fill a 5-gallon bucket to within an inch of the rim.
- Mark the waterline INSIDE the bucket AND on the pool.
- Wait 24 hours. Both will lose some water to evaporation.
- If the pool dropped more than the bucket, you have a leak.
Most common Vegas causes, in order
- Toilet flapper (cheap fix, $10)
- Underground irrigation crack (we'll find it acoustically)
- Slab leak — hot side (acoustic + electronic pinpoint)
- Water mainline service leak (between meter and house)
- Pool plumbing leak (dye + pressure testing)
- Water heater or softener malfunction (visible inspection)
When to call us
If you've checked toilets and watched the meter and you're still seeing usage, call us at (702) 682-1626. Our High Water Bill Investigation runs $250-$450 and almost always pays for itself in the next billing cycle. We use pressure isolation testing to systematically narrow down the leak, then acoustic + electronic detection to pinpoint it.
Most customers see their next bill drop 50-80% after we fix the cause.
"The first thing I tell people on the phone: check your toilets. Half the time, that's it — and they save themselves a $300 service call. I'd rather you save the money than pay me to find a 50-cent flapper." — Matt, owner