Engineers put a spaniel in the works to help find tricky Langdale leak

What do you get when you spend hours searching soggy fields for a water leak which almost left a tiny Lake District hamlet with dry taps?

Answer: A tennis ball and a nice bath in a muddy puddle.

If that doesn’t sound like much reward for a job well done, then you’re not Denzil.

Denzil is United Utilities’ leak-detecting super hound that finds the burst pipes other technology cannot.

After months with dwindling water supplies, residents near Little Langdale were facing the prospect that their leak may never be found.

The small collection of just four homes was connected to the public water network by a private supply pipe running about half a kilometre across open fields.

They knew where the pipe joined United Utilities’ water mains network. They knew where it connected to their homes. But, being an old private pipe, its actual location was not marked on any surviving plans.

Anxious to help, United Utilities water customer manager for Cumbria, Mike Welch brought in his team with their listening sticks.

“Although we have lots of sophisticated technology like acoustic alarms and artificial intelligence for finding water leaks on our network, it’s a different story on a private pipe in the countryside. Especially in the middle of fields. The only thing on our side is that the area is remote and quiet enough to use listening sticks. These are a traditional tool to help you hear the noise of an underground leak. But without knowing exactly where the pipe ran, it was just about impossible,” he said.

Having had luck with sniffer dogs on other rural pipes, Mike drafted in dog trainer Luke Jones and his springer spaniels Denzil and Kilo to try his luck.

Denzil and Kilo are trained to detect the smell of chlorine, which is something you only find in treated water, not in rain water or ground water.

Said Luke: “It took us a couple of hours, because there were so many places the pipe could be, and there were several fields to cover. Basically we walked back and forward in lines across each field until Denzil picked up the smell. I used Denzil rather than Kilo because he is more experienced.

“Normally, I the dogs walk in a straight line on larger rural trunk mains because we know where the pipes are. This was good training for Denzil. I brought Kilo back later, once mine and Denzil’s scent had gone, to give him some training in the new technique, and he found the leak too.

“We don’t work on small domestic supply pipes often. But as long as there’s clean water for him to find, Denzil will pinpoint the leak. For one we had to search about 20 fields. It took a week, but he found it.”

Denzil’s reward for success is to get to play with his favourite toy, a tennis ball.