Abstract: Freshwater is a vital resource in Australia, and its availability is highly variable in semi-arid and arid. Rapidly expanding water resource development in the Murray Darling Basin (MDB) has impacted natural flow regimes and the ecological integrity of many dryland rivers and their large floodplain wetlands. Efforts to manage and conserve the surface waters of rivers in the MDB are hampered by limited scientific data regarding historical and contemporary flow and inundation patterns and of responses of flora and fauna to the high natural variability of flow regimes that typify the lowland-dryland rivers.