Just north of Windorah, the Barcoo River and the Thompson River join to form the famous (in Oz anyway) Cooper Creek where Windorah is located.
The creek, which is often nothing more than a series of water holes, drains south through places like Innamincka and eventually into the Lake Eyre basin.
During floods, it spreads out into hundreds of channels that, along with channels formed by the Georgina and Diamantina Rivers go to make up The Channel Country.
I'm not too sure how we can have two rivers joining to form a creek but that's what happens in the outback.
Your description reminded me of "A Bush Christening" :)
On the outer Barcoo where the churches are few,
And men of religion are scanty,
On a road never cross'd 'cept by folk that are lost,
One Michael Magee had a shanty......
On the outer Barcoo where the churches are few,
And men of religion are scanty,
On a road never cross'd 'cept by folk that are lost,
One Michael Magee had a shanty......