Security Of Supply
The application of the seasonal allocation principles determine the security of water supply for irrigators.
For example, on the Goulburn River system (supplying the Shepparton, Central Goulburn, Rochester-Campaspe and Pyramid-Boort Areas and river diverters along the Goulburn River), 100% or more of water right and licensed volume would be supplied in 97 years out of 100. The lowest seasonal allocation in the last 100 years would have been about 75% of water right and licensed volume. Very low seasonal allocations only occur at the end of drought sequences lasting a few years. In the 100 year sequence, high seasonal allocations (around 200%) would occur in about 60 of those years.
The same seasonal allocation principles produce different results for the other water supply systems, depending on the particular river flow regime and the capacity of the storages. Notably, Victoria's share of the River Murray system has a similar likelihood of water right and licensed volume being received as for the Goulburn River system, but is much more likely to receive high seasonal allocations.
