Why Is My Water Bill So High? 9 Common Causes and How to Check for a Leak

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By Efrain Realzola
Real Texas Plumbing, Heating and Air, serving Lago Vista, Jonestown, Lakeway and the Lake Travis area. Updated November 2026.

Your water bill is high for one of three reasons: you used more water, water is leaking somewhere, or the bill doesn't match what your meter actually read. Most of the time it's a leak, and most leaks can be found with a ten-minute meter test and a walk around the house.

Here's the order we'd check things in, cheapest and fastest first.

The most common reasons a water bill spikes

• A running or silently leaking toilet (toilet repair)

• A leaking sprinkler line, a zone stuck on, or a pool auto-fill that won't shut off

• A hidden leak under the slab, inside a wall, or on the buried line from the meter (leak detection)

• A leaking water heater or a failing relief valve (water heater repair)

• Water pressure that's too high

• A water softener stuck in its cleaning cycle (water softener repair)

• Dripping faucets, showerheads and worn appliance lines (faucet repair)

• A cracked or corroded pipe (broken pipe repair)

• A billing issue: an estimated read, a longer billing period, or normal seasonal use

Step 1: Do the meter test

This tells you whether water is moving through your plumbing when nobody is using any. You don't need tools.

Reading the meter. The numbered row is your running total. The small dial, triangle or star is the leak indicator. Meters count in gallons or cubic feet depending on your utility, and one cubic foot is about 7.5 gallons, so check your bill to see which unit yours uses.

1. Stop all water use. Nobody showering, dishwasher and washing machine off, sprinklers off, and no one flushing. Ice makers will refill on their own, so give them a minute to finish.

2. Find your meter. It's usually in a ground box near the street or the edge of your property, with a lid marked for water. Lift the lid with a screwdriver rather than your fingers, and look first. Fire ants, spiders and the occasional snake like those boxes.

3. Look for the leak indicator. Most meters have a small dial, triangle or star that spins when even a trickle of water passes through. If it's turning with everything off, water is moving somewhere.

4. Write down the meter reading, wait two hours without using any water, and read it again. The EPA says that if the reading changes at all, you probably have a leak.

5. Now shut off your home's main water valve and check the meter again. If the indicator stops, the leak is inside your house or at the water heater. If it keeps turning, the leak is on the buried line between the meter and your house.

That last step matters. It tells you whether you're hunting for a leak you can reach (a toilet, a fixture, an appliance) or one underground, which needs a professional.

If the meter isn't moving at all, the problem is probably usage, a leak that only runs at certain times (like sprinklers), or the bill itself. Keep reading.

What your meter test is telling you

• Indicator still and the reading unchanged after two hours: There's no constant leak. Look at leaks that come and go (sprinklers, a softener, a toilet that only runs now and then) and at the bill itself.

• Indicator turning slowly, and it stops when you shut off the main: A small leak inside the house, like a toilet flapper or a dripping fixture. Go to Step 2.

• Indicator spinning fast, and it stops when you shut off the main: A bigger leak inside, such as a failed supply line, an appliance hose or the water heater. Look for wet floors and walls, and don't wait.

• Indicator still turning with the main shut off: The leak is on the buried line between the meter and your house, or the main valve isn't sealing. That's a job for leak detection.

Step 2: Check the usual suspects

Toilets. A running or silently leaking toilet is the most common cause we know of. Put a few drops of food coloring in the tank, don't flush, and wait ten minutes. If color shows up in the bowl, the flapper isn't sealing. The EPA says a worn flapper can silently leak thousands of gallons a year, and suggests replacing flappers at least every five years. If your home has a grinder pump, a leaking toilet sends all that water to the pump, so a pump that's kicking on more often than it used to is a clue worth following.

Need help? Our toilet repair service covers running and leaking toilets. If a toilet is cracked or beyond repair, we also handle toilet installation.

Sprinklers and irrigation. This is the one people miss. The EPA estimates a leak only 1/32 of an inch wide, about the thickness of a dime, can waste around 6,300 gallons a month. Run each zone and look for geysers, soggy spots, sunken ground, or a zone that won't shut off. Check the timer too. A schedule left on summer settings in the fall adds up fast.

Who fixes it? Sprinkler heads, valves and zone lines are usually an irrigation specialist's job, and the EPA suggests hiring a WaterSense-certified irrigation professional. If the leak is in the pipe that feeds the system from your house, that's plumbing, and it's what leak detection is for.

Pools, fountains and auto-fill valves. A stuck auto-fill will keep topping off water that's draining or evaporating, and you'll never see it.

Water heater. Look at the base of the tank, the shutoff and supply connections, and the pipe coming off the relief valve. A steady drip from that pipe can mean the relief valve is failing or your water pressure is too high.

Repair or replace? A leaking fitting, valve or relief valve is a water heater repair. A tank leaking from its body can't be patched and has to be replaced. Standard tank water heaters run $2,200 to $4,400 installed (see water heater installation). If you'd rather upgrade, we also install tankless units (tankless installation).

Water pressure. Screw a pressure gauge onto an outdoor spigot. Over 80 psi is too high. High pressure makes valves and fittings leak and wastes water at every fixture. A failed pressure-reducing valve is a common reason, and it's a quick fix once it's found. Homes on hilly lots around Lago Vista and Lake Travis can see a lot of pressure variation, so it's worth knowing your number.

You can see this kind of work in our project gallery: Water Pressure Solutions for Safer Homes and Restoring Full Water Flow With Valve Replacement.

Water softener. A softener stuck in its cleaning cycle can send water down the drain around the clock. If you hear water running at the softener's drain line when nothing else is on, that's your answer.

Fix it: water softener repair. If your softener is old, or you're deciding whether you need one, see water softener installation and water filtration system installation. Hard water doesn't raise your bill by itself, but mineral buildup can clog aerators and wear out fixtures and your water heater sooner.

Faucets and showerheads. A faucet dripping once a second wastes more than 3,000 gallons a year, and a showerhead dripping ten times a minute wastes more than 500, according to the EPA. Worth fixing, but a drip alone rarely explains a big jump in one bill.

Fix it: faucet repair for drips, and faucet installation when a fixture is worn out.

Under the sink. Open the cabinet and look at the supply lines, the drain connections and the garbage disposal. A slow disposal leak can drip into the cabinet for months without you noticing. See garbage disposal repair.

Appliance lines. Check behind and under the washing machine, dishwasher, refrigerator and ice maker for damp floors, stains, or swollen cabinet bases.

Rubber washing machine hoses are a common failure point. If one is bulging, cracked or more than a few years old, replace it, and consider braided stainless hoses.

Step 3: Think about hidden leaks

If the meter kept moving after you shut off the main, or you've checked everything above, the water is going somewhere you can't see: inside a wall, under the slab, or underground.

Signs to look and listen for:

• The sound of running water when everything is off

• A warm or damp spot on the floor

• A patch of yard that's soggy or much greener than the rest, especially between the meter and the house

• Wet ground near the meter box

• A drop in water pressure

• A musty smell, stains, or mold that keeps coming back

A lot of lots in Lago Vista, Jonestown, The Hollows and Point Venture are large, and the line from the meter to the house can be long. More pipe means more places for a leak to hide. Central Texas soil also swells and shrinks with the weather, which can stress pipes under and around a slab.

Don't wait on a suspected hidden leak. It wastes water every day, and it can damage flooring, drywall and your foundation while it runs.

How a plumber finds a hidden leak

Plumbers narrow it down in stages. They confirm the leak with the meter, close the main to separate the house from the buried line, test sections of pipe, and then pinpoint the spot before anything is dug up or opened. The goal is to cut into as little yard, slab or wall as possible. That diagnosis step is what leak detection is for.

Repair options for a hidden leak

• Spot repair: cut out the damaged section and replace it (broken pipe repair)

• Reroute: run a new line around the slab, through the attic or through a wall when the leak is under the foundation

• Repipe: when pipes are old, corroded or leaking in more than one place, replacing the whole line can make more sense than chasing leaks (repiping)

What affects the cost

Where the leak is matters most. A leak in the yard is usually simpler than one under the slab or inside a finished wall. The depth and length of the line, the pipe material and age, how much has to be opened and restored, and whether there is one leak or several all move the price.

We give you a written price before any work starts. The trip charge is $65, and it's applied toward the work when you schedule the job.

Step 4: Check the bill itself

Sometimes the plumbing is fine. Look at the bill before you tear into walls.

• Compare this bill to the same month last year, not last month. Water use jumps in summer for reasons that have nothing to do with leaks.

• Check the length of the billing period. A 35-day cycle will cost more than a 28-day one.

• Compare the reading on the bill to your meter today. If the bill used an estimate, or the numbers look off, call your water utility and ask for a re-read.

• Think about what changed: houseguests, a new pool fill, new sod or landscaping, a new irrigation schedule, a long stretch of hot weather.

• Do the math. Take the extra gallons on this bill compared to a normal one and divide by the days in the cycle. If you used 30,000 gallons and normally use 8,000, that's 22,000 extra gallons, or about 730 gallons a day. That's more than a dripping faucet can explain.

As a rough benchmark, the EPA says a family of four using more than 12,000 gallons in a cold month like January or February likely has a serious leak.

How much water can a leak waste?

These are the EPA's figures, from its Fix a Leak Week guidance:

• A faucet dripping once a second: more than 3,000 gallons a year

• A showerhead dripping 10 times a minute: more than 500 gallons a year

• A worn toilet flapper: thousands of gallons a year, often with no sound

• A sprinkler leak 1/32 of an inch wide: about 6,300 gallons a month

• The average home's leaks: more than 9,300 gallons a year, and about nine percent of homes leak 50 gallons or more a day

The EPA also says that fixing the easy leaks can save about 10 percent on a water bill. A big spike usually comes from something larger than a drip, like a sprinkler zone, a hidden line, or a toilet that runs all day.

If you find a leak, do this right away

1. Shut off the water at the fixture's own shutoff valve, or at the main if you can't find it.

2. Take a photo of the meter reading and the leak indicator.

3. Keep every receipt and repair invoice.

4. Call your water utility and ask whether they offer a leak adjustment on the bill. Policies differ from one utility to the next, and many want proof that the leak was repaired, so ask before you pay.

When to call a plumber

Call a plumber if:

• The meter keeps moving after you shut off the main

• You hear water running with everything off

• You find wet ground, a warm spot on the floor, or a sudden drop in pressure

• Your water heater is leaking

• You've checked everything above and still can't find it

When you call us, the trip charge is $65, and it's applied toward the work when you schedule the job. You get a written price before any work starts. We handle leak detection, broken pipe repair, toilet repair, faucet repair, water heater repair, water softener repair and grinder pump service for homes.

We're a family-owned shop with locations in Lago Vista (20811 Dawn Dr, Unit 706) and Lakeway (2802 Flintrock Trace). We serve homes in Lago Vista, Jonestown, The Hollows, Highland Lake Estates, Northshore on Lake Travis, Point Venture, Lakeway, Bee Cave, Horseshoe Bay, Marble Falls, Cedar Park, Leander, Crystal Falls Parkway, Anderson Mill, Round Rock and Austin. Our hours are Monday to Friday, 7:30 a.m. to 8 p.m., and Saturday, 8 a.m. to noon. We don't dispatch overnight, so if you find an active leak after hours, shut off the main valve and contact us when we open.

We'd rather you find a running toilet yourself in ten minutes than pay for a service call. If you've done the meter test and it points to something you can't reach, that's what we're here for. You can learn more about our family-owned shop or browse recent jobs.

How to keep it from happening again

• Know where your main shutoff valve is, and turn it once a year to make sure it still works. A stuck valve is no help in an emergency.

• Replace toilet flappers about every five years, as the EPA suggests.

• Swap rubber washing machine hoses for braided ones, and replace any that bulge or crack.

• Check your water pressure once or twice a year. If it reads over 80 psi, have a pressure-reducing valve looked at.

• Walk your sprinkler zones each spring and any time the bill jumps.

• Look under sinks and around the water heater every few months.

• Shut off the main when you leave for more than a few days, especially at a lake or second home that sits empty.

• Consider a smart leak detector or flow monitor. The EPA has a guide to leak detection and flow monitoring devices.

• Ask about plumbing maintenance so small problems get caught before they show up on a bill.

• If your home has older pipes that keep leaking, ask whether repiping makes sense.

Frequently Asked Questions

Why is my water bill suddenly so high?

Usually a leak, a change in how much water you used (sprinklers, a pool fill, houseguests), or a billing issue like an estimated read or a longer billing period. The meter test in Step 1 tells you which one you're dealing with.

How do I check my water meter for a leak?

Stop all water use, look at the leak indicator on the meter, and note the reading. If the indicator is turning, or the reading has changed after two hours with no water used, you likely have a leak. Shut off the main valve and check again to find out whether the leak is inside the house or on the buried line.

How much water does a running toilet waste?

The EPA says a worn flapper can silently leak thousands of gallons a year. A food coloring test takes ten minutes and shows you whether yours is leaking.

Can a leak under the slab or in the yard raise my water bill?

Yes. A hidden leak wastes water around the clock even though you can't see it. Warning signs include the sound of running water, a warm spot on the floor, a soggy or unusually green patch of yard, and a meter that keeps moving after you shut off the main valve.

Can my grinder pump make my water bill higher?

No. A grinder pump moves wastewater out of your home and doesn't draw from your water supply. But a pump that cycles more often than usual can be a sign that water is going down your drains when you aren't using it, such as from a leaking toilet.

Who is responsible for a leak between the meter and my house?

Usually the homeowner is responsible for the line on the house side of the meter. Check with your water utility to confirm where their responsibility ends.

Will my bill go back to normal after the leak is fixed?

Your next full billing period should show it. Keep your repair invoice, and ask your utility whether they offer a leak adjustment on the high bill.

How do I read my water meter?

Open the meter box lid and find the row of numbers (your total) and the small dial, triangle or star (the leak indicator). Meters read in gallons or cubic feet depending on your utility, and one cubic foot is about 7.5 gallons. Write down the total, wait, and compare.

Can high water pressure cause a high water bill?

It can contribute. Pressure over 80 psi stresses fittings and can cause leaks at valves, supply lines and the water heater's relief valve. A gauge on an outdoor spigot shows your number, and a failed pressure-reducing valve is a common cause of high pressure.

Can a leaking water heater raise my bill?

Yes. A slow drip from a fitting, valve or relief valve runs around the clock. If the tank itself is leaking, it needs to be replaced. See water heater repair and water heater installation.

Could my water meter be wrong?

It's possible, but a leak is far more common. Compare the reading on your bill to the meter itself. If the bill used an estimate or the numbers don't match, ask your utility to re-read it and check the meter. Do the meter test first so you know whether water is really moving.

Does fixing a small leak really lower my bill?

The EPA says fixing easily corrected household leaks can save about 10 percent on a water bill. The bigger savings come from finding the large leak behind a spike, like a sprinkler line or a buried pipe.

Should I shut off my water when I travel?

For trips of more than a few days, yes, and especially for a lake house or second home that sits empty. With the main closed, a failed hose or supply line can't run unnoticed.

My bill is high and I can't find a leak. What now?

Repeat the meter test with the main shut off. If the meter is still, look at the bill: an estimated read, a longer billing period, new sod, a pool fill or a sprinkler schedule. If the meter keeps moving, call a plumber for leak detection.

Does Real Texas Plumbing serve my area?

We serve homes around Lake Travis and Central Texas, including Lago Vista, Jonestown, Lakeway and the other communities listed above. If you don't see your neighborhood, contact us and ask.

Does Real Texas Plumbing do leak detection?

Yes. See our leak detection service. The trip charge is $65, applied toward the work when you schedule the job.