The Big River, an inland perennial river of the Goulburn Broken catchment, part of the Murray-Darling basin, is located in the lower South Eastern Highlands bioregion and Northern Country/North Central regions of the Australian state of Victoria. The headwaters of the Big River rise on the northern slopes of the Yarra Ranges and descend to flow into the Goulburn River within Lake Eildon.
The Big River flows over the Northern slopes of the Yarra Ranges and into the Goulburn River that is within the Murray-Darling basin.
We don't know that the rivers flow into the Murray-Darling basin which is what the Big River is a part of.  The system didn't catch geographical uncertainty.
( z1 flow :ARG1 ( z2 river :name ( z3 name :op "Big" :op "River" ) ) :path ( z4 slope :mod ( z5 north ) :mod ( z6 mountain :name ( z7 name :op "Yarra" :op "Range" ) ) ) :destination ( z8 river :name ( z9 name :op "Goulburn" :op "River" ) :location ( z10 basin :name ( z11 name :op "Murray-Darling" ) ) ) )