Why Is My Water Bill So High?
A water bill that suddenly climbs almost always comes from one of three places: a leak, a change in how much water the household uses, or an issue with the meter or the bill itself. This guide walks through every common cause, shows you how to test for a leak in a few minutes, and explains when it is time to call a plumber.
By Yorba Linda Plumbing Pros · Published · Updated
What Usually Causes a High Water Bill?
The most common causes of a high water bill are a running toilet, an irrigation problem and a hidden leak in a pipe you cannot see. Seasonal watering, house guests and filling a pool can also push use up without anything being broken.
Use this table to match what you are seeing with the most likely cause.
| What you notice | Most likely cause | First thing to check |
|---|---|---|
| Bill jumped, nothing looks wet | Running toilet or hidden leak | Food coloring test, then meter test |
| Bill higher only in summer | Irrigation schedule or a broken sprinkler | Controller settings and a walk of each zone |
| Soggy patch in the yard | Service line or irrigation leak | Meter test with the house valve closed |
| Warm spot on the floor | Hot water line leaking under the slab | Meter test, then call a plumber |
| Hissing toilet tank | Worn flapper or fill valve | Dye test in the tank |
| Steady drip at a faucet | Worn cartridge or washer | Tighten the handle, then repair |
| Bill jumped for one cycle only | Longer billing period or a meter read issue | Compare usage units and billing days |
How Much Water Can a Leak Really Waste?
More than most people expect. The U.S. Environmental Protection Agency's WaterSense program estimates that household leaks waste nearly 180 gallons per week in the average home, about 9,400 gallons a year. About 5 to 10 percent of homes have leaks that waste 90 gallons or more every day.
| Leak | Water wasted (EPA WaterSense estimates) |
|---|---|
| Average household leaks | About 9,400 gallons a year |
| Faucet dripping once per second | More than 3,000 gallons a year |
| Shower dripping 10 times a minute | More than 500 gallons a year |
| Large hidden leaks in some homes | 90 gallons or more per day |
The EPA also notes that fixing easy household leaks can cut a water bill by about 10 percent. A hidden slab or service line leak can waste far more than that.
How Do I Check My Water Meter for a Leak?
The meter test is the single best way to know if water is escaping. If the meter moves while nothing in the house is using water, you have a leak somewhere.
Step 1: Stop All Water Use
Turn off every faucet and make sure the dishwasher, washing machine, ice maker, water softener and sprinklers are not running. Ask everyone in the house not to flush for a while.
Step 2: Find and Read the Meter
The meter usually sits in a concrete box near the street at the front of the property. Lift the lid carefully and look for the leak indicator, a small triangle, star or dial that spins whenever water moves through the meter.
Step 3: Watch and Record
If the indicator turns, water is flowing. For a slow leak, write down the full reading, wait one to two hours without using any water, and read it again. Any change means a leak.
Step 4: Split the House From the Yard
Close the main shutoff valve where the water line enters the house and watch the meter again. If it still moves, the leak is most likely in the service line between the meter and the house, or in the irrigation system. If it stops, the leak is inside the house.
If the meter keeps moving and you cannot find the cause, our leak detection team can pinpoint it without tearing up floors.
How Do I Find a Leaking Toilet?
Toilets are the most common source of silent leaks, and the test takes 15 minutes. Add a few drops of food coloring to the tank, wait without flushing, then look in the bowl. Any color in the bowl means water is leaking past the flapper.
Check every toilet, including guest baths that are rarely used. Also look inside the tank: if water is spilling into the tall overflow tube, the fill valve is set too high or failing. The EPA suggests replacing toilet flappers about every five years, since rubber hardens and stops sealing. Our toilet repair page explains the fix.
Could My Sprinklers Be the Cause?
Yes. Outdoor watering is one of the biggest water uses in a Southern California home, so a broken head, a cracked lateral line or a stuck valve can raise the bill fast, and nobody notices because it happens at night.
- Walk each zone while it runs and look for geysers, broken heads or water pooling.
- Look for a spot that never dries, even when the system is off.
- Check the controller for extra start times, a schedule left on summer settings or a seasonal adjustment set too high.
- Turn the controller off and repeat the meter test to rule the system in or out.
The EPA estimates that a WaterSense labeled smart irrigation controller can cut irrigation water use by about 15 percent in an average home, which is worth considering if outdoor use is the main driver.
What About Faucets, Showers and the Water Heater?
Small fixture leaks add up across a full billing cycle. A faucet or showerhead that drips steadily usually needs a new cartridge, washer or seal, and it is a quick repair. See our faucet and fixture repair page.
The water heater can waste water too. A relief valve that keeps discharging, a leaking drain valve or a tank seeping from the bottom all send water out of the system. Check the discharge pipe outside and the floor around the tank.
Could the Bill Itself Be Wrong?
Sometimes the bill is higher without any leak at all. Before you assume the worst, compare the usage units on this bill with the same month last year, not just the dollar amount.
- Billing period length. A cycle with more days shows more use.
- Rate changes. Water rates and service charges can change from year to year.
- Estimated reads. If a meter could not be read, the bill may have been estimated and corrected later.
- Seasonal patterns. Summer irrigation can double use compared with winter.
If the usage units really did jump and your meter test shows no leak, call your water provider and ask them to recheck the read and review your usage history.
Meter moving and no leak in sight? Call and we will find it
What Should I Do Next?
Work through the checks in order, from the easiest to the most involved.
- Compare usage units with the same month last year.
- Run the food coloring test on every toilet.
- Walk the irrigation system and check the controller.
- Do the meter test, first with the house valve open, then closed.
- Look for warm floors, damp walls and wet spots in the yard.
- Call a plumber if the meter moves and you cannot find the source.
Yorba Linda Plumbing Pros can help with any of these, from a flapper swap to pinpointing a slab leak.
High Water Bill FAQs
Straight answers to what Yorba Linda homeowners ask us most. Still unsure? Call and ask a plumber.
Call (657) 359-9180Why is my water bill high when I have no leaks?
If the meter test shows no leak, the higher bill usually comes from more use or the bill itself. Longer billing periods, summer irrigation, house guests, filling a pool and rate changes all raise the total. Compare the usage units with the same month last year and ask your water provider to recheck the read if something looks off.
Can a running toilet really raise my bill that much?
Yes. A toilet with a worn flapper can leak water into the bowl around the clock, often without a sound, and over a full billing cycle that adds up to thousands of gallons. A food coloring test in the tank shows the leak in about 15 minutes, and a new flapper is a quick, low cost fix.
How do I know if the leak is between the meter and my house?
Close the main shutoff valve where the water enters your house, then watch the meter. If the leak indicator still moves with the house valve closed and the sprinklers off, the leak is most likely in the service line between the meter and the house. A plumber can locate and repair that line.
How long should I watch the meter for a leak test?
A fast leak shows on the meter's leak indicator within a minute or two. For a slow leak, write down the full reading, avoid using any water for one to two hours, and read it again. Any change in the number means water is escaping somewhere in the system.
Who pays for a leak on my side of the meter?
In most cases, the property owner is responsible for pipes on the house side of the water meter, including the service line to the home and everything inside. The water provider is usually responsible for the meter and the line on the street side. Your provider can confirm where the line falls.
Will a slab leak show up on my water bill?
Often, yes. A leak in a water line under the slab runs constantly, so it can raise the bill month after month before any water appears on the floor. A warm spot on the floor, the sound of running water or a meter that moves with everything off are the other common clues.
Call About a High Water Bill in Yorba Linda
If the meter is moving and you cannot find the cause, call now. We will track down the leak and give you the price to fix it before any work starts.