There really aren't many cities ANYWHERE where people actually live on narrowboats any more. One of them is Cambridge. The Cam is a dozy little river and everyone jokes about it being dirty. It's pretty full of bikes (like everywhere else in the city), but as rivers go it's pretty clean I think. If you have got drunk and gone punting and bridge-jumping, and then drunk too much Cam water...that's a whole different thing. It has fish and birds and all sorts. At least ones that can cope with the tourists. And people really, genuinely, live on it, in the way that they have continually since probably forever. Though they do have things like solar panels now, and cabins bigger than 10' by 5'.
This guy is growing rainbow chard, as well as tomatoes and some other stuff. Not sure you can see it in the picture but he is. I planted some, but in the previous house. I'll have to go and see how it's doing when I head over for dinner this week. He wasn't the only one, either.