Leak detection programme prevents millions of litres of water loss

4/08/2020
Watercare’s proactive leak detection programme has prevented millions of litres of water loss at a crucial time for Auckland’s water supply.

Watercare chief executive Raveen Jaduram says the programme – which finds invisible leaks by listening for distinctive leak sounds – was accelerated this year as the region suffered the worst drought on record.

“We’ve covered more than 500 kilometres of pipes already and identified – and fixed – leaks with an estimated total volume of more than 2 million litres a day (MLD),” he says.  

The programme has focused on areas in Auckland with the most reported leaks, including Mt Wellington, Ellerslie, New Lynn, Māngere, Ponsonby and Herne Bay.

“By July next year, we expect to have covered more than 6000 kilometres – almost two thirds – of Auckland’s water pipes,” Jaduram says.

Acoustic leak detection involves listening for signs of a leak by tapping a stick microphone to a meter or pipe connection. Leaks have a distinctive sound as they are constantly running.

“We check at several times of the day to confirm it is a leak. We can then estimate the volume of the leak based on the sound detected – a big leak will be a loud leak.”

Jaduram says the acoustic leak detection work is just one element of a wider programme to minimise water lost to leaks.

“We spend more than $20 million a year replacing ageing water pipes and their supporting infrastructure.

“We have also put more crews in the field so we can investigate and fix reported leaks as soon as possible. We aim to repair urgent leaks within a few hours, and all leaks within five days, but sometimes, due to the location of the leak and factors like traffic management, they do take longer.”

While every effort is being made to reduce leakage in Auckland, leaks are inevitable in all water networks around the world.

“We have more than 9000 kilometres of pipes in Auckland and millions of separate joins. It’s not just old pipes that leak. In a hot, dry summer, the ground retracts and causes pipes to break. And any vibration – even that of heavy traffic – can cause cracks. In the past year, we had more than 1000 incidents of watermain damage caused by a third party working in the ground.

“Auckland actually has one of the better leakage rates in New Zealand but we know there’s room for improvement, and we are committed to bringing our leakage rate down. The leak detection programme will play a significant part in that.”

Jaduram also urges Aucklanders to check their own private plumbing for leaks.

“There are more than 440,000 connections to our network, and each has its own network of private plumbing – there could well be more kilometres of private pipes in Auckland than there are public, so if everyone was to carry out a simple leak test, the potential for water savings is huge.”

Click here to learn how to check for a leak at home