The Study Area for Gulargambone is located at the confluence of the Castlereagh River (catchment area 7,000 km2 at the confluence) and Gulargambone Creek (catchment area 600 km2 creek outlet). The Study Area is situated on the Castlereagh Highway approximately 50km north of Gilgandra and 45km south of Coonamble in the central west of NSW.

Due to the close proximity of two major waterways and the relatively flat terrain of the Study Area, the village of Gulargambone has experienced in excess of 12 flood events since 1950 with local overland flows causing flooding in low lying areas in 2010.