The seasonal determination in the Broken system has increased from 46 per cent of high-reliability water shares (HRWS) to 47 per cent HRWS.
Seasonal determinations in the Goulburn and Loddon systems are unchanged at 73 per cent.
The Bullarook seasonal determination remains at 33 per cent.
The Murray and Campaspe systems are unchanged at 100 per cent.
Resource Manager Mark Bailey said hot and dry conditions meant there was very little resource improvement since the last assessment.
“Hot conditions and a lack of rainfall across northern Victoria meant evaporation and river operating requirements were close to our estimates in most systems,” Dr Bailey said.
“Slightly lower than estimated operating requirements in the Broken system allowed the small seasonal determination increase announced today.”
Eildon Reservoir in the Goulburn system, has slipped below 50 per cent of capacity.
Eildon now stands at 48.7 per cent of capacity, Dartmouth 70 per cent, Hume 27.7 per cent, Goulburn Weir 96 per cent, Waranga Basin 43 per cent and Nillahcootie 56 per cent.
The Bureau of Meteorology is forecasting maximum temperatures in the mid 30s this coming week.