How has flow regime changed in Yarra River?
Change in Flow Regimes: A high proportion of the yield for the Yarra River Basin is derived from the Upper Yarra catchment, which contributes approximately 50% of the mean annual flow. The unregulated streams in the Basin exhibit distinct seasonal flow patterns, with up to 60% of the annual flow occurring in the winter and spring months. The highest flow period extends from August to November, with 55% – 60% of the flow occurring during this time. March through to May are the lowest flow months, with total flow representing 3% to 4% of the average annual flow. September is the highest flow month, with total flow representing up to 34% of the average annual flow. The flows of the Yarra River are highly regulated by the Upper Yarra Reservoir, Maroondah Reservoir, and other storages, and are reduced by major diversions for the Melbourne water supply system. The flow downstream of the Upper Yarra Reservoir has been significantly reduced from an estimated average annual flow of 150,500 ML t
