A trio of teenagers has won national support for their quacking invention, which could change the way pollution is detected in the world’s waters.

Over just four days, Ben Hope, Harri Bell-Thomas, both 18, and Benedict Allen, 17, brought Watt the Duck to life at Monmouth School in preparation for a national coding competition.

Under their team name, Buoy, the pupils put together a “genius combination” of Raspberry Pi computers, sensors and a duck to revolutionise how data from oceans, rivers and lakes is collected.

More than 1,200 children from 66 centres across the UK flocked to Birmingham’s ICC for Young Rewired State’s Festival of Code.

After gruelling presentations to industry experts at the “world’s largest hackathon”, judges crowned them winners of the Code a Better Country category.

And after a successful campaign, the boys have just won the following public vote (decided on the number of YouTube views) to crown the people’s favourite finalist out of 16.

Team Buoy’s presentation video was watched 2,508 times – more than 1,550 times more than their closest rivals’.

Harri said: “I’m absolutely ecstatic.

“When presenting Watt the Duck, it was apparent we’d struck a chord both with the judges and the audience – our Twitter hashtag, #WattTheDuck, got a laugh every time we presented.

“Over the course of the weekend, we became used to our new names as the ‘duck guys’, and definitely enjoyed our momentary fame.”