Nicole Harvey left her secure job of 20 years when she met Joey the springer spaniel — and she has never looked back. 

"There was something about him that I went, 'I want to follow this dog as far as he can go'," she said.

Ms Harvey was working as a biosecurity dog handler for postal services at the Sydney Airport when she met Joey, who was then eight weeks old.

Her dog handling mentor Steve Austin was about to train him for Sydney Water.

Ms Harvey wanted in, and she quit her job to follow Joey.

At that time, there was little known about using dogs for water detection projects, but she took the leap anyway.

"We had nothing to compare it to," she said.

A trip to the country

Now three years later, Joey, Ms Harvey and Hydro — another detection dog with Sydney Water — are on the hunt for leaky pipes across regional New South Wales to save water in a drying climate.

The team is part of a state government program designed to preserve drinking water supplies in rural areas.

The dogs have sniffed out 14 holes in Parkes, two in Orange and are working towards heading back out to areas like Bathurst.

Their adventure in the regions comes after the team detected 325 leaks in the Sydney region alone, across more than 550 kilometres.

Ms Harvey said the canines had a unique ability to find cracks.

"What they're really good at is finding those tiny leaks before they become big leaks — so that's their specialty … compared to other devices that are out there."

The Joey and Hydro, who both belong to Sydney Water, have been trained to sniff out the chlorine and fluoride added to drinking water, and are taught to avoid control samples of rain, dam and river water.

Big savings using leak detection

Department of Planning and Environment water efficiency manager Jethro Laidlaw said it was even more important to find leaks in rural areas.

"And that's just a circumstance of long distances, not as many properties, [and] lots of water mains to look after underground."

He said the canines' work was an important way to help local councils divert money into more important projects.

"Every litre found has been pumped, it's been treated, it's got fluoride put in it — so saving water is a great way to save money," he said.

"As we are coming into this drier time … it's never more important to think about our water use."

A pup that's one in a million

Ms Harvey said watching Joey thrive and help save water was immensely gratifying, after the leap of faith she took three years ago.

"Joey's actually one of those dogs that's one in a million," she said.

"I am so, so lucky to be able to work with him — because his personality, his work ethic, is like nothing else you'll ever see."

And Ms Harvey has made sure that relationship will endure for a long time.