New water year outlook for Murray-Darling Basin looks positive after water trifecta

The Murray-Darling Basin Authority (MDBA) released its annual operating outlook for the 2020-21 water year, which highlighted three things - a wet autumn, higher dam levels and more rain on the way.

MDBA executive director Andrew Reynolds the organisation was "cautiously optimistic" this water would be better than the previous.

"The outlook is better than the same time last year because we've got the trifecta we've been waiting for," Mr Reynolds said.

"Catchments are primed after the wet autumn, we've got more water in storage compared to the same time last year and the Bureau of Meteorology is forecasting higher than average spring rainfall," Mr Reynolds said.

As of the end of July, southern basin storages were at 51 per cent, compared to 40pc at the same time last year.

"We're still a way off filling the storages, but the critical mid-Murray storage at Lake Victoria is close to capacity, thanks to good winter flows from the tributaries downstream of Hume Dam," Mr Reynolds said.

"This means less of the supply to South Australia will need to come from the Hume, as it's sitting there in Lake Victoria now, ready to go."

Mr Reynolds said although the forecast predicted good rainfall, the MDBA had to plan for a range of conditions.

"Nobody knows for sure what the weather will bring," he said.

"If conditions revert to a drier scenario, we need to be ready for it, so we continue to operate the system as effectively and efficiently as possible."

There is an on-going risk of a delivery shortfall, where demand outstrips MDBA's ability to move water through the system.

"This year the Outlook considers the shortfall risk to be greatest in late summer and autumn under moderate or near-average rainfall scenarios," Mr Reynolds said.

An updated version of the outlook will be published at the end of October, following the normal winter-spring inflow, which will give a clearer picture of water availability.