A continuous leak, particularly a running toilet, concealed pipe leak or irrigation fault, is often the biggest cause of an unexplained water bill increase because it can waste water around the clock. If there is no leak, heavy use such as garden watering, pool filling or long showers is the more likely cause.
Common causes of a high water bill
Check for continuous leaks before reviewing changes in household use:
- Running toilets: Listen for trickling into the bowl or a cistern refilling when nobody has flushed.
- Concealed pipe leaks: Warning signs include unexplained dampness, reduced pressure or running-water sounds behind walls, under floors or underground.
- Irrigation leaks: Split pipes, damaged sprinkler heads or faulty valves may leak during or after operation.
- Dripping taps: Persistent drips add to metered consumption.
- Increased use: Longer watering cycles, pool filling, long showers, visitors or changed routines can explain higher consumption.
How to narrow down the cause
- Compare consumption: Check the kilolitres used and the number of days in the billing period, rather than comparing only the amount charged. Consider recent watering, pool use, visitors or routine changes.
- Look and listen: Check accessible toilets, taps and irrigation, and look for damp areas. Do not remove fixtures, excavate or enter confined spaces.
- Check the meter: Turn off all taps, irrigation and water-using appliances, but leave the main supply on. Record the meter reading, use no water, including flushing toilets, for one hour, then check it again.
- Interpret the result: A changed reading means water passed through the meter. Recheck that every fixture and appliance was inactive. If the meter remains still, increased household or outdoor use is more likely than a continuous leak.
If water is near electrical equipment, do not touch the equipment or enter the wet area. Keep clear and seek urgent help from the electricity network operator or emergency services if there is immediate danger.
When to call a plumber
Contact an appropriately licensed plumber if the meter continues moving with all known outlets off, or if you suspect a concealed, underground or pressurised pipe leak. Do not attempt to expose or repair concealed plumbing yourself.
If escaping water is causing damage, turn off the property’s water supply only if you know the correct valve and can reach it safely. Our licensed Sydney plumbing team can locate the leak and advise on the required repair.