For the last 15 years, N S Rajappan has been steadfast in his mission; cleaning Kerala’s Vembanad lake, which forms part of the state’s famed backwaters, in his own way.

His legs paralysed since birth, Rajappan crawls on his hands to reach his tiny wooden yacht every morning, leaving for the lake in search of plastic water bottles — an unrewarded effort hailed by Prime Minister Narendra Modi in his Mann Ki Baat on Sunday.

The 72-year-old, who lives at Arpookkara in Kottayam, has never undertaken any work for livelihood and stays with his younger sister Vilasini, a daily worker. “I don’t look into the distance I cover every day. I would go through the lake and its tributaries wherever possible, looking for plastic bottles,” said Rajappan, adding that he returns only once his tiny vessel is full of empty bottles. “I take the vessel to a safe location, mostly near bridges, to sleep in it during night. Sometimes, houseboats would directly hand over the bottles to me,’’ he said.

Back home, Rajappan stocks the bottles to be sold later. “I don’t make much money from this as one kg of empty water bottles would fetch only Rs 3,” he said.

Rajappan, who never attended school, said it was sheer curiosity that drove him towards this effort and he never realised its importance. “But people, who used to watch me collect the bottles every day, told me that I was doing something big. Recently, local people photographed me and circulated it (on social media). I hope my work will help others realise how plastic waste pollutes our lakes and rivers,” he said.