Chasing mysterious smell with Blueye Pioneer in the Nidelven river in Trondheim

During this summer a mysterious smell occured in the city of Trondheim, Norway. The smell reminded of exhaust, asphalt or burnt rubber. One theory is that the source of the smell could originate from the Nidelven river that runs between Midtbyen and Brattøra. We were asked by the local newspaper, Adresseavisen, to bring our underwater drones and film the seabed in the canal to investigate if we could see any irregularities and perhaps uncover the mystery!