Fortunately it was insured so he bought a new bike which he takes as far as Napier, 20km away from his Hastings home.
It's not just rubbish Denis collects.
"I was working down at Splash Planet and next thing a lady comes in with a box of chocolates. 'Thank you very much for handing my wallet into the police station'."
He said the litter problem is improving and he's proud of the contribution he has made.
"A lot of people say 'It's because of what you are doing, that's why it is better'. Other people say '[In the] early days we used to drop the rubbish. Now we've seen you going around we don't do it any more'."
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