UK.
Howard - Bourne as in the Ingrebourne in Essex describes a particular type of river. For most of the year they are shallow with a low water flow, but at times of heavy regional rainfall suddenly shift a very large amount of water. As a result, they are often a very narrow, but deep cut channel.
In 1979 I was working with the fisheries department of the then Thames Water Authority and we were doing a fish population survey of the Ingrebourne and the river Beam, which turned into the Rom before joining the Thames through the Ford car factory at Dagenham.
Quite often, on the river you were in knee high water between river banks that were above head height.
Quack!
Geoff the Duck.