Surely you mean the Murrumbidgee River ?
I have no idea what sort of worm this is. But at a guess, it might be some sort of intestinal worm. Being on or near the Bidgee such a worm could survive long enough for you to find it and take a photo of it. It might have come from road kill, picked up by a bird and then dropped. Plenty of road kill around Gordon...rabbits, foxes, roo's etc.
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