I like "Senior River".

It flows better. Not that your version isn't wonderful, just that in my mind a correct--I mean, alternatively acceptable--number of syllables that fits the metre of the original song is an equally valid choice.

OK, I'll stop now.

Except to say...
About 10 or 15 years ago there was a huge controversy in Toronto the Good concerning some peoples' objections to a production of "Showboat" due to allegations that it stereotyped black people and made their past a spectator sport, or whatever. These folks formed "The Coalition To Stop Showboat", which struck me as the hugest waste of activist energy in the history of Toronto.   
One of them got the "Bonehead Media Comment" of the year when she suggested publically that shows offensive to black people are usually promoted by Jews. Way to stop racism in its tracks, lady!

"Showboat" went ahead, and ironically a few years later the promoter of the show, Garth Drabinsky, went to jail for massive show-biz financial fraud. But I don't believe presenting "Showboat" was part of the case against him...

If it was good enough for Paul Robeson (after he fixed the lyrics he didn't like), it's OK by me!

W-O