There used to be a [Water bus](https://www.google.com/maps/@55.8565032,-4.2592711,3a,75y,190.74h,91.64t/data=!3m6!1e1!3m4!1sBYaO9BOuKHW2BmqCZ2QIJg!2e0!7i16384!8i8192) at some point. But I've never seen it active in my lifetime.
I wouldn't be shocked if someone said it was an old Victorian era thing that got canned during the war.