Campaspe and Broken seasonal determinations have reached 100 per cent of high-reliability water shares.
Northern Victoria resource manager Dr Mark Bailey said the Murray system had jumped 20 pc, to 77pc HRWS, while the Goulburn and Loddon systems increase from 71pc HRWS to 85pc HRWS.
Seasonal determinations in the Bullarook system stayed at 100pc HRWS and 100pc LRWS.
Dr Bailey said recent rainfall provided a welcome increase in water availability.
"The catchments responded well to the rain in early September," Dr Bailey said.
"The volume of water in storage increased and higher tributary flows downstream of the storages met demand, which allowed for today's increased allocations.
"The Murray-Darling Basin Authority is also managing Lake Hume close to the full supply level."
That reduced the volume of rules-based accounts in the Murray system, and might cause deductions from spillable water accounts if releases continued.
"Any deductions from spillable water accounts will be determined in early October and included in the October 15 seasonal determination assessment."
Read more: Hume Dam and Menindee Lakes have filled
The latest Bureau of Meteorology seasonal outlook continues to favour above-average rainfall across the northern Victoria for the three month period from October to December.
The negative Indian Ocean Dipole has weakened but continues and the Bureau has also issued a La Nina watch meaning the chance of a La Nina forming is around 50pc.
A negative Indian Ocean Dipole and La Nina each increase the likelihood of above-average rainfall totals in south-east Australia.