TMWA Meter Test in Sparks: Find Out in 20 Minutes If You Have a Leak
Your water meter tells the truth before any wall shows damage. This is TMWA's own test, step by step, with what your reading means and what to do next. It costs nothing, takes 20 minutes, and works on the AMI smart meter most Sparks homes already have.
Why the meter test comes first
A high water bill is the number one reason Sparks homeowners call us, and the meter is the fastest way to find out whether that bill is a leak or just usage. TMWA has documented a single yard-line leak running 800,000 to 900,000 gallons in a month, about 20 gallons a minute, for four months, and it never surfaced. The bill would have passed $10,000. A leak like that does not wait for a wet spot on the floor.
The meter test answers one question only: is water moving when everything is off? If the answer is yes, you have a leak, and the test also tells you whether it is inside the house or out in the yard line. It does not tell you exactly where the leak is. That is the next step, and that is what acoustic listening and thermal imaging are for.
TMWA meter test, step by step
Do it in the morning, when nobody needs water for 20 minutes. You need nothing but a flashlight and a pen.
Turn off all water
Turn off every tap, toilet, appliance and irrigation zone. Turn off the ice maker, the water softener and the pool autofill. Tell everyone in the house: nobody uses water during the test, not even a toilet flush.
Find the meter and record the reading
Find your meter box, usually at the curb, and lift the lid. It may be stiff, and a screwdriver helps. Note the reading and the position of the low-flow indicator, the small triangle on the dial. That triangle is what you will watch.
Watch the flow indicator for 20 minutes
If the indicator moves with everything off, water is leaving the system somewhere. Any movement means a leak, and a steady spin means a big one. Do not use any water during these 20 minutes, or the test tells you nothing.
Close the house shut-off valve
If the meter is moving, close the valve where the water line enters the house, then watch the meter again. If the meter stops, the leak is inside or under the house. If it keeps moving, the leak is likely in the yard line between the meter and the house.
The small triangle is the whole test
That triangular flow indicator is the most sensitive part of the meter. A leak too small to move the numbers will still turn the triangle. If it is dead still with everything off, no water is flowing right now. If it creeps, even slowly, something is leaking.
If the 20-minute test shows nothing but your bill is still high, try the longer version: read the meter before bed, use no water overnight, and read it again in the morning. The EPA recommends a 2-hour no-use test for slow leaks the short test can miss.
What your reading means
Flow indicator moving
Water is flowing with everything off. You have a leak somewhere. A steady spin means a large leak, and the bill is climbing every hour it runs.
Meter stops at the house valve
The leak is inside or under the house. Next step is acoustic and thermal detection on the indoor lines, and the slab if the house is on a slab foundation.
Meter keeps moving
The leak is in the yard line between the meter and the house. That is underground leak detection, and it is the line that produced TMWA's 800,000-gallon case.
Set up your TMWA leak alert
Most Sparks homes now have an AMI smart meter, and TMWA lets you set a leak alert on it for free. TMWA recommends setting the alert at 5 gallons per hour for 24 hours.
Sign in at myaccount.tmwa.com
Go to myaccount.tmwa.com and sign in to your TMWA account.
Open Smart Meter
Find the Smart Meter section in your account dashboard.
Set the Leak Alert
Set it to 5 gallons per hour for 24 hours, the level TMWA recommends.
The alert watches for continuous flow. A normal home has hours with no water use at all, usually overnight. A leak never stops, so 24 hours of unbroken flow is the pattern the alert catches. It will not find the leak for you, but it will tell you the day one starts, instead of the month your bill arrives.
The numbers that tell you it is a leak
Every figure below comes from TMWA or the EPA, not from us. Use them to judge your own bill.
About 6,000 gallons a month
Winter indoor use of a family of four, according to TMWA. If your winter use is far above that with no change in habits, a leak is the first thing to check.
More than 12,000 gallons a month
The level the EPA points to as a sign of a serious leak for a family of four in winter, when irrigation is off or minimal.
More than 8,500 gallons a month
What a toilet leaking 1 gallon every 5 minutes adds. About 20 percent of toilets leak slightly, and the flapper is the most common indoor leak. TMWA has documented toilet leaks of 144,000 and 164,000 gallons in a single month.
800,000 to 900,000 gallons a month
TMWA's documented yard-line leak, running about 20 gallons a minute for four months, never surfacing, with a bill that would have passed $10,000. Another leak under a deck registered 300,000 gallons a month against a 6,000-gallon average, with no visible puddles.
Sources: TMWA, Facts About Leaks (tmwa.com), and EPA WaterSense. No bill-adjustment or leak-credit policy from TMWA was found, so we do not claim one exists.
Check your toilet first
The toilet flapper is the most common indoor leak, and it is the cheapest to rule out.
Drop food coloring in the tank
A few drops is enough. Do not flush.
Wait 15 to 30 minutes
Do not flush during the wait, or the test tells you nothing.
Check the bowl for color
If color shows up in the bowl, the flapper is leaking water from the tank into the bowl, around the clock.
Do this on every toilet in the house, one at a time, and check the meter again after each one. If the meter stops moving after a toilet is shut off, you found it. If the meter keeps moving with every toilet off, the leak is somewhere else, and the meter test has done its job.
Who to call first, TMWA or a plumber?
One thing to know before you call anyone: TMWA states that you are responsible for the water usage at your home or business, even if that usage is from a leak. The usage stays on your bill. That is why the meter test matters early, a leak found in week one costs far less than the same leak found in month four.
Call TMWA first
Schedule a water usage review. Conservation staff will visit, help you read the meter, check the toilet flappers, and work out whether the usage pattern looks like a leak. They do not find or fix the leak itself.
Then call us to find it
If the meter test shows a leak, we find it with acoustic listening and thermal imaging, mark the spot, and give you a written report with the location.
Have ready when you call: your last two TMWA bills, any meter readings you took, and the symptom in one line, high bill, sound, warm floor, wet yard, or falling pool level.
TMWA meter test questions we hear every week
Straight answers about the TMWA meter test, leak alerts, and what your bill is telling you.
How do I check my TMWA meter for a leak?
Turn off all water in and around the house, find the meter box at the curb, and note the reading and the flow indicator. Watch the indicator for 20 minutes without using any water. If the indicator moves or the reading changes, water is flowing somewhere it should not be, and you have a leak. TMWA's own guidance is the source for this test, and it works on the AMI smart meters most Sparks homes now have.
How do I set up a TMWA leak alert?
Sign in at myaccount.tmwa.com, open Smart Meter, then Leak Alert. TMWA recommends setting the alert at 5 gallons per hour for 24 hours. The alert watches for continuous flow and tells you when water has been running without a break, which is the pattern a hidden leak makes. It costs nothing and runs on the smart meter TMWA already installed.
How do I check my toilet for leaks?
Put a few drops of food coloring in the toilet tank, then wait 15 to 30 minutes without flushing. If color shows up in the bowl, the flapper is leaking water from the tank into the bowl. TMWA calls the toilet flapper the most common indoor leak, and about 20 percent of toilets leak slightly. A toilet leaking 1 gallon every 5 minutes adds more than 8,500 gallons a month.
How do I find a hidden leak?
Start with the 20-minute meter test. If the meter moves, shut off the toilets one at a time and check the meter again after each one, because a toilet flapper is the most common cause. If the meter still moves with every toilet off, close the house shut-off valve: if the meter stops, the leak is inside or under the house; if it keeps moving, the leak is in the yard line. That is as far as the meter can take you, and it tells us exactly where to start listening.
Is my high bill a leak or just irrigation?
Compare your usage with TMWA's benchmark: a family of four uses about 6,000 gallons a month indoors in winter. If your winter use is far above that with no change in habits, a leak is more likely than irrigation, because irrigation is off or minimal in winter. In summer, turn the irrigation off for a day and run the meter test. If the meter still moves, the leak is not the sprinklers.
Am I responsible for water usage even if it was a leak?
Yes. TMWA states that you are responsible for the water usage at your home or business, even if that usage is from a leak. That is why a meter test matters early: a leak that runs for months is billed for months. TMWA can send conservation staff for a water usage review, but the usage itself stays your responsibility.
Can TMWA do a water usage review at my home?
Yes. Call TMWA at 775-834-8080 to schedule a water usage review, and conservation staff will visit. They can help you read the meter, check the toilet flappers, and work out whether the usage pattern looks like a leak. They do not find or fix the leak itself. If the review points to a hidden leak, that is when you call us for acoustic and thermal detection.
Why did my TMWA bill jump 20 to 40 percent?
A sudden 20 to 40 percent jump with no change in habits is a classic supply-line leak signal. A small leak running all day and night adds up fast: a toilet leaking 1 gallon every 5 minutes adds more than 8,500 gallons a month, and TMWA has documented a yard-line leak running 800,000 to 900,000 gallons a month that never surfaced. Run the 20-minute meter test first. If the meter moves, you have a leak, not a billing error.
When the test says there is a leak
Water Leak Detection
When the meter says water is flowing but you cannot see where, our water leak detection service tracks it behind walls, under sinks, and in ceilings with the same acoustic and thermal tools.
Learn more →
Underground Leak Detection
If the meter keeps moving with the house valve closed, the leak is in the yard line between the meter and the house. Our underground leak detection service covers that run.
Learn more →Areas we serve
Serving Sparks & Surrounding Areas · Based in Sparks, NV. Seven neighborhood areas, matched to the ZIP codes where our service is focused. If your street sits between two areas below, you are still in Sparks. Call and give us your ZIP.
Central Sparks →
Downtown Sparks, Victorian Square, and Greenbrae. Older housing stock, where original plumbing is now at its highest-risk age.
Spanish Springs →
Including Los Altos. Larger lots, longer yard lines.
Wingfield Springs →
Higher and more exposed, the freeze-risk area we watch most closely in December and January.
Kiley Ranch →
Newer master-planned homes, now old enough for first-generation fitting and water heater failures.
D'Andrea →
Including Pioneer Meadows and Stonebrook edges. Hillside lots, where yard leaks can travel before surfacing.
Sparks Marina →
Around the marina and its surrounding streets, in Sparks, NV 89431.
East Sparks →
East Sparks and the Vista Boulevard area, including Stonebrook.
ZIP codes in our core service area
Serving Sparks, NV and Washoe County, in Sparks, NV 89431. We name only the areas we actually serve on this page.
Not sure if we cover your street? Call (775) 505-6540 and give us your ZIP code.
Your meter says there is a leak. Now let us find it.
If the test showed water moving with everything off, the next step is detection, not guesswork. We find the leak with acoustic listening and thermal imaging, mark the spot, and give you a written report. Emergency service available.