Bicycle in river, Kyoto

I cannot convey the exact feeling that I had seeing this bicycle in the river in Kyoto.
How did it get here? Did someone have an accident? Was it thrown in?
It was the first real sign to me of the “unmanicured” side of Japanese life, of which I had not seen much sign of on my trip before this. It was not the last, either.
Key: R20070207-112209-crop2