(CNN) After racing a yacht from London to Rio de Janeiro, adventurer Dhruv Boruah learned that another team taking part in that same race had come across two turtles tangled in plastic in the middle the Atlantic Ocean. Thinking about all the other victims of plastic pollution in our oceans, Boruah was compelled to act.

So, back home in London, he pieced together a bamboo bicycle, put yellow floats on either side, and added a rudder and a pedal-powered propeller to the front. Then, with a fishing net hooked on either side, he began cycling on the city's rivers and canals collecting plastic waste.

The idea is not to singlehandedly rid London's waterways of plastic — that's too big a job for one man on a floating bicycle.

Instead, Boruah, 35, uses his comical contraption to strike up conversations with curious onlookers.

"It's a great conversation starter, and then I can tell them about my work, the plastic, and how it all starts here in the canals," Boruah tells CNN while balancing on his bike in London's Regent's Canal.

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