In search of a word

[The Backlash Cometh]

What is the opposite of a tributary? Instead of a stream that flows into a river, what would you call a stream that breaks away and follows a different course from the main body? It probably wouldn't last very long, maybe just during flooding, but it's definitely a different body from the main river course?

[jotsy]

1. irrigation ditch,

siphon channel?

[jtuck004]

2. A fork. n/t

[nuxvomica]

3. A "distributary"

http://en.wikipedia.org/wiki/Distributary

[The Backlash Cometh]

4. Thanks everybody! They're all going to be helpful