A survey of hydrological changes to wetlands of the Murrumbidgee River

The Floodplain (1974 flood height) of the Murrumbidgee River between Wagga Wagga and Hay Weir in New South Wales encompasses 174,700 ha. In this study area, open water wetlands occupy 2,005 ha and red river gum wetlands occupy 47,075 ha. A total of 570 ha of the red river gum has been killed by increased inundation. Fifty one percent of the open water wetlands (62% of total area) have been affected by local hydrological change. Water levels in 11% of open water wetlands (24% of total area) are now heavily controlled, and 31% (36% of total area) have been made permanent. the water regimes of Murrumbidgee wetlands are less altered that those of Murray River wetlands, but their extent of local hydrological control is similar to wetlands of the Namoi River. Future wetland surveys should record the degree and type of control of their water regimes.