Why is my water bill suddenly so high? How to check for a hidden leak

A municipal bill that jumps for no obvious reason is one of the most common calls we get. Nobody changed their habits, nobody filled a pool, and yet the consumption figure has doubled. Nine times out of ten, the answer is a leak you cannot see.

Here is how to check for yourself before you call anyone, and what to do if the checks point to a leak.

Step 1: Rule out the obvious

Before suspecting a hidden leak, walk the property. Check every toilet for a quiet trickle into the bowl - food colouring in the cistern makes it easy to spot: if colour appears in the bowl without flushing, the flush valve is leaking. Check garden taps, the geyser overflow pipes on the roof or outside wall, and any irrigation system. A toilet running silently can lose hundreds of litres a day, and it is a cheap fix.

Step 2: Do the water meter test

This is the test that settles it. Turn off every tap and water-using appliance in the house, then watch your water meter for fifteen minutes. If the meter has moved while nothing was using water, water is leaving the system somewhere, and you have a leak.

Step 3: Look for the quiet signs

Hidden leaks leave clues: warm patches on the floor (a hot-water pipe leaking under the screed), mould in places that should not be damp, the faint sound of running water at night, or a lawn patch that stays green and soggy through summer. Old galvanised pipes, common in Cape Town's older suburbs, are frequent offenders: they corrode from the inside until pinholes open up.

Step 4: Get the leak found, not guessed at

If the meter test says you have a leak but you cannot see it, resist the urge to start opening walls. Professional leak detection equipment - acoustic listening gear, thermal imaging and moisture meters - finds the leak first, so only the repair spot gets opened.

Can you claim back the excess from the City?

Often, yes. The City of Cape Town has a leak rebate process for excessive consumption caused by an undetected leak. The conditions: the leak must be repaired by a registered plumber, and you apply with the plumber's report and proof of repair. We provide exactly that documentation with every leak repair.