Why Has My Water Bill Suddenly Increased?

Opening a water bill that is double what you normally pay is a genuinely unsettling moment. Your habits have not changed, nobody has moved in, and yet the numbers say your property has used far more water than usual.

In many Perth homes there is a simple explanation. In others, the extra usage is being caused by a leak you cannot see, hear or find. Working out which situation you are in is the first step, and you can do most of that yourself before calling anyone.

Start by ruling out the everyday explanations

Water Corporation bills usually arrive every two months, so a single bill covers a long stretch of time. A few weeks of unusual activity can quietly inflate the total.

Before assuming the worst, think back over the billing period and consider:

Reticulation and garden watering. Perth summers push usage up sharply, and a reticulation controller that has been set to run longer or more often is one of the most common causes of a spike. The winter sprinkler ban also means your summer bills will look very different to your winter ones.
Extra people in the house. School holidays, visiting family or a new housemate can add thousands of litres over two months.
A new pool, spa or large garden bed. Filling and topping up uses more water than most people expect.
A change in the way you are being billed. Check whether the reading was an actual meter read or an estimate. An estimated reading followed by an actual one can create a catch-up bill.

If none of these apply, it is worth checking the meter properly.

How to check your water meter for a hidden leak

This test takes about half an hour and gives you a clear answer.

Turn off every tap inside and outside the house. Switch off the dishwasher, washing machine, ice maker and reticulation controller.
Find your water meter, usually near the front boundary of the property.
Write down the full reading, including the red or black digits that measure smaller volumes.
Do not use any water for at least 30 minutes.
Read the meter again.

If the reading has moved, water is going somewhere. Many meters also have a small triangular or star shaped leak indicator that spins when water is flowing. If that dial is turning while everything is switched off, you almost certainly have a leak on your property.

Common causes of unexplained water usage

Leaking toilets

A cistern that seeps water into the bowl is silent and can waste a very large volume over two months. Put a few drops of food colouring in the cistern, wait 20 minutes without flushing, and check whether colour appears in the bowl.

Underground service pipe leaks

The pipe running between your meter and your home is your responsibility. When it leaks underground, the water often disappears into sand without ever surfacing, which is why so many Perth properties show high usage with no visible sign of a problem.

Slab leaks

Leaks in pipework beneath a concrete slab can go undetected for months. Warm spots on the floor, damp skirting boards, unexplained damp patches on walls or a hot water system that runs constantly can all point to one.

Reticulation faults

A cracked poly pipe or a solenoid valve that is not sealing properly will keep drawing water every time the system runs, and sometimes in between.

When it is time to bring in a leak detection specialist

If your meter is moving with everything switched off but you cannot find the source, the leak is almost certainly hidden underground, under concrete or behind a wall. This is the point where guessing becomes expensive.

Subtronic Leak Detection uses non invasive methods including acoustic listening equipment, thermal imaging and electronic detection to pinpoint the exact location of a leak without digging up your yard or cutting into your home first. We locate the leak and advise on next steps. Your plumber then carries out a targeted repair, rather than exploratory work across the whole property.

For homeowners, landlords and property managers across Perth, Mandurah and Rockingham, that difference usually means less disruption, less damage and a much smaller repair bill.