For many homeowners, the situation starts with a letter, phone call, or smart meter alert from the water company.
Water usage is unusually high. Continuous flow has been detected. A leak is suspected somewhere on the property.
Then comes the next stage:
“The leak appears to be on your side.”
But after that, things often become much less clear.
The house may already have been checked. A plumber may have looked around. The water company may have ruled out part of the external supply.
Yet despite all of that:
- the water meter is still moving
- usage is still high
- there is no obvious burst pipe
- nobody can actually find the leak
This is one of the most common situations homeowners face with hidden water leaks.
What Does “On Your Side” Actually Mean?
When the water company says a leak is “on your side,” they usually mean the water loss appears to be occurring somewhere within the private pipework you are responsible for.
This may include:
- the underground supply pipe after the meter
- pipework entering the property
- internal plumbing systems
- concealed water supplies
- pipework beneath floors or driveways
However, this still does not identify exactly where the leak is located.
It simply narrows down which part of the system may require investigation.
Why Some Leaks Are Extremely Difficult to Find
Many hidden leaks do not behave like obvious burst pipes.
Instead, water may escape slowly and continuously into surrounding materials or underground areas for a long time before visible symptoms appear.
Leaks are often hidden:
- beneath concrete floors
- inside wall cavities
- under driveways or patios
- within underground supply pipes
- behind fitted units or bathrooms
- along concealed pipe routes
Some leaks create visible damp quickly. Others lose significant amounts of water while leaving very little obvious evidence behind.
Why the Meter Keeps Moving Even When Nothing Looks Wrong
This is one of the biggest frustrations for homeowners.
The property appears dry, there is no obvious flooding, and yet the meter continues to register constant usage.
That is because hidden leaks may:
- disperse underground gradually
- travel beneath floors before surfacing
- soak into surrounding ground
- escape into cavities or voids
- remain hidden beneath solid floors
As a result, the amount of water being lost can appear completely disproportionate to the visible signs inside the property.
Why Initial Checks Sometimes Don’t Find the Leak
Many homeowners understandably assume that if a plumber or initial inspection did not immediately locate the problem, the leak may not be serious.
But hidden leaks are often much more complex than visible plumbing faults.
A standard inspection may rule out:
- obvious appliance leaks
- visible pipe damage
- overflow problems
- simple plumbing faults
However, concealed leaks often require a much more detailed investigation process.
That is especially true where pipework runs underground, beneath floors, or inside inaccessible areas of the property.
Why “Leak Confirmed” Is Different From “Leak Located”
This is an important distinction.
Water companies are often able to confirm abnormal usage or continuous water loss through meter data and monitoring.
But accurately locating the source of hidden leakage is a separate stage of the process entirely.
Professional non-invasive leak detection may involve:
- acoustic tracing
- thermal imaging
- tracer gas testing
- pressure testing
- sectional isolation testing
- moisture investigation
Some leaks are relatively straightforward to trace. Others require detailed specialist investigation to narrow down the exact location within concealed systems.
Could the Leak Still Be Outside?
Yes.
Even where no obvious external flooding is visible, leaks on underground supply pipes can still lose substantial amounts of water below ground.
Water may disperse:
- through surrounding soil
- beneath hard surfaces
- along utility trenches
- towards drainage paths underground
This is one reason supply pipe leaks are often much harder to locate visually than homeowners expect.
Why Specialist Mains Water Leak Detection May Be Needed
Once a hidden leak has been confirmed but not located, specialist investigation is often the next stage.
Professional non-invasive mains water leak detection focuses on accurately tracing concealed water loss within:
- underground supply pipes
- incoming water supplies
- concealed plumbing systems
- wall cavities
- concrete floors
- hidden pipe routes
The Leak Hunter carries out specialist non-invasive mains water leak detection across concealed water systems and hidden plumbing infrastructure.
As a WaterSafe Register registered company, we investigate hidden leaks using specialist diagnostic methods designed to locate the source accurately while minimising unnecessary disruption.
You can learn more about professional mains water leak detection and how concealed leaks are professionally traced before repairs begin.
Frequently Asked Questions
What does it mean when the water company says the leak is on your side?
It usually means the suspected leak appears to be somewhere within the private pipework or plumbing system the homeowner is responsible for after the water meter.
Can a hidden leak lose a lot of water without visible damage?
Yes. Many concealed leaks lose water underground, beneath floors, or inside cavities where the escaping water may remain hidden for a long time.
Why would the water meter keep moving if nothing looks wrong?
Hidden leaks can continue losing water continuously even where there is no obvious flooding or visible damp inside the property.
Can a supply pipe leak stay hidden underground?
Yes. Underground supply pipe leaks often disperse into surrounding soil or beneath hard surfaces without immediately appearing above ground.
What happens after a hidden leak is located?
Once the exact source is identified, the appropriate repair approach can then be planned based on the type, location, and accessibility of the affected pipework.