OK, I'll have a go, see what fragments come out.

When the weather is fine, it's really high time
For messing about on the river.
********************
For messing about on the river.
There's tug boats and row boats and *** boats and ****
**********************************
So take off your coat, and go get afloat
Go messing about on the river.

The above is part memory, part I fear invention. It goes in in a similar vein for several more dire verses, of which there are none in my head. I have no words other than those I quoted for the parody I mentioned above, I'm afraid. That's me, I'm done.