Drainage and river flow
The river drainage system across this part of New South Wales is controlled by the major geological faults traversing the region. This is illustrated by the adjacent map showing major Lachlan Orogen faults and the rivers of the upper Murrumbidgee River catchment area.
The area of Murrumbidgee - Ginninderra Gorges National Park includes the landscapes formed over an extended period of geological time when erosion carved river courses through weaknesses in the rocks and developed two significant features:
- Waterfalls on Ginninderra Creek near its confluence with the Murrumbidgee River as it makes a river course flowing westward from the higher ground to the northeast of the Deakin Fault.
- Gorges developed on the Murrumbidgee River north of the Ginninderra Creek confluence where the river carves its way through units of the Laidlaw Volcanic Suite and Laidlaw Volcanic Suite to the north of the Winslade Fault.
Both features are key elements of the Murrumbidgee - Ginninderra Gorges National Park and will be a great attraction for visitors to the park from the nearby population centres and elsewhere, not just for recreation but also for education and appreciation of the natural environment (Doug Finlayson, 2011)
Upper Murrumbidgee River drainage system with superimposed major geological faults (red).
The Murrumbidgee River at Cusacks Crossing.