You open your water bill and the number is two or three times higher than normal. Nothing has changed in your household — same number of people, same routines, no new appliances. Something is wrong, and in most cases, the answer is a hidden water leak somewhere in your plumbing system.
Here is how Katy homeowners can track down the source of a water bill spike and what a plumber can do that you cannot.
The Meter Test: Start Here
Before you call anyone, do a simple test. Turn off every water-using fixture and appliance in your home — sinks, showers, toilets, washing machine, ice maker, irrigation system, everything. Then go to your water meter and watch the dial or flow indicator. If it is still moving, you have an active leak somewhere between the meter and your home or inside the house.
This test does not tell you where the leak is, but it confirms that the high bill is not a billing error. If the meter stops when everything is off, the issue may be a running toilet or a fixture that cycles intermittently — which we will cover below.
Running Toilets: The Silent Bill Killer
A running toilet can waste 200 gallons of water per day — that is over 6,000 gallons per month — without making enough noise for you to notice. The flapper valve inside the tank deteriorates over time and allows water to seep continuously from the tank into the bowl. The toilet refills automatically, creating a slow but constant cycle of waste.
Check each toilet in your home by putting a few drops of food coloring in the tank. Wait 15 minutes without flushing. If the color appears in the bowl, the flapper is leaking. This is one of the most common and most affordable plumbing repairs, but it accounts for a significant percentage of unexplained water bill increases in Katy homes.
For more on toilet issues, read Quick Fixes for a Leaky Toilet.
Slab Leaks: Hidden and Expensive
Many Katy homes are built on concrete slab foundations with water supply lines running underneath or within the slab. When one of those pipes develops a leak — from corrosion, soil movement, or material failure — the water has nowhere to go but into the soil beneath your home.
Symptoms of a slab leak include warm spots on the floor (if the leak is on a hot water line), the sound of running water when nothing is on, cracks in the foundation or walls, and mold or mildew smell in specific areas. Slab leaks are difficult to detect without professional equipment and should be addressed quickly to prevent foundation damage.
If you suspect a slab leak, our post on warning signs of a slab leak covers the details.
Irrigation System Leaks
Katy homeowners with in-ground sprinkler systems often overlook this as a source of high water bills. A broken sprinkler head, a cracked lateral line, or a stuck valve can waste enormous amounts of water — especially during the summer months when the system runs frequently. Check for unexplained wet areas in the yard, sprinkler heads that are not spraying properly, and zones that seem to run longer than they should.
Underground Water Line Leaks
If the meter test shows active flow and you have ruled out toilets, fixtures, and irrigation, the leak may be in the main water line that runs from the meter to your home. This is a pressurized pipe, so even a small crack can lose a significant volume of water daily.
Signs include wet spots in the yard along the line path, discolored water, and a noticeable pressure drop. This type of leak requires professional detection equipment and repair — it is not a DIY job. Learn more about the full scope of water line repair and replacement we provide.
How a Plumber Finds Leaks You Cannot See
At GAL Plumbing Industries, we use electronic leak detection equipment that pinpoints leaks behind walls, under slabs, and underground without tearing up your property. This technology allows us to locate the exact spot of the leak, confirm the source before any demolition or excavation, and recommend the most targeted (and least expensive) repair approach.
We also check for hidden leaks throughout your home during the diagnostic process, because it is not uncommon to find more than one contributing issue.
Stop Paying for Water You Are Not Using
A high water bill in Katy is almost always a plumbing problem with a solution. Whether it is a $15 toilet flapper or a main water line repair, fixing the leak stops the bleeding on your bill and protects your home from water damage.
Call GAL Plumbing Industries at (832) 906-1141 or schedule a leak detection visit online. We serve Katy, Cinco Ranch, West Houston, Sugar Land, Fulshear, and surrounding areas.
Related reading: Detect Water Leaks Before They Cause Damage | Essential Plumbing Maintenance Tips for Your Katy, TX Home









