As of Tuesday, June 27, Lake Eildon’s storage level was 97.2 per cent. G-MW is aiming to reduce this to 94 per cent by August 1.
Target filling points are guided by the Victorian Water Act 1989 to protect the reliability of water entitlements, while offering some flood mitigation.
Target filling points are required to be based on inflows expected in 95 years out of 100, meaning Lake Eildon will reach full capacity each year, with the exception of very dry years.
The current level of Lake Eildon is largely attributed to the higher than average rainfall from three consecutive La Niña events and a negative Indian Ocean Dipole.
Due to a wet June, G-MW adjusted the filling targets, now aiming to have Eildon full by November 1, instead of October 1.
The Bureau of Meteorology’s three-month climate outlook indicated that, as of June 15, there was a 60 per cent to over 80 per cent chance of below median rainfall across Australia.
The bureau has issued an El Niño alert, which means there is about a 70 per cent chance of El Niño, La Niña’s drier cousin, forming in 2023.
G-MW said downstream impacts were considered in any Lake Eildon water release, particularly for private land, which is affected before the minor flood levels are reached.
Water resources manager Mark Bailey said G-MW would continue to monitor the conditions and adjust fill and release rates as necessary.
“G-MW has reduced releases from 12,000ML per day in response to increased tributary flows,” Dr Bailey said.
“Releases are currently at 11,000ML per day (as of June 27) and are likely to resume at 12,000ML per day in the coming days after these tributaries fall.
“These releases are expected to continue through July. Minor adjustments will be made to accommodate any increased inflows downstream of Eildon and to minimise bank erosion.”
More information and the latest updates on Lake Eildon can be found at the G-MW website: https://www.g-mwater.com.au/eildon-management