The first results were promising and Vattenfall is now looking at whether the dogs can replace the current thermal imaging cameras used for water leak detection.

Mark Spithorst, piping technical specialist at Vattenfall, came up with the idea of using sniffer dogs. Together with Scent Imprint for Dogs (SIFD), a Dutch company that provides dog detection training, he set up a special training for leak detection in district heating pipes.

The dogs were trained using the scents from demineralised water and polyurethane. Demineralised water is released when a heating pipe leaks, and polyurethane can be detected when water from outside the pipe enters the heat pipe’s insulated polyurethane jacket.

Three dogs are currently trained. Harry and Nemo specialise in detecting demineralised water and Juro is a specialist in sniffing out polyurethane. When the dog finds a spill, it sits down and points to the area with its nose.

Mark Spithorst, piping technical specialist at Vattenfall, said: “Normally, we locate leaks by aiming a thermal imaging camera at the ground and at homes. Of course, residents often react to this and wonder what we are doing pointing a camera at their house. We get the same when we are tracking leaks with the dogs, but the residents are usually enthusiastic, and interested in what we are doing.”

Wesley Visscher of Scent Imprint for Dogs (SIFD) said: “We selected dogs that enjoy this type of work. They are very enthusiastic and have a great time. Of course, we make sure they don’t work too hard by alternating the dogs and letting them rest regularly.”

At the moment, the dogs are only used in Almere, a province in The Netherlands, with the aim of rolling out the training so that detection dogs can be used in more places.