A remote sensing approach to determine environmental flows for wetlands of the Lower Darling River, New South Wales, Australia

A remote sensing approach was adopted to determine environmental flow requirements for wetlands in the Lower Darling River. The regulation of river flows by the Menindee Lakes Storage has altered the natural flow regime in the river and is likely to be affecting the health of both the river and its wetlands. Landsat Thematic Mapper (TM) images corresponding to four flood events (1989, 1990 and two in 1996) were analysed and a relationship between river flow heights and wetland inundation was established. Wetlands were classified according to broad commence-to-flow river discharges. The study concluded that 13 000 Ml d(-1) (megalitres per day) at Weir 32 would inundate approximately 50% of the wetlands along the Lower Darling River, this figure being 10 000 Ml d(-1) less than estimated in a previous study.