The river likely peaked at 7.55 metres on Saturday afternoon, the State Control Centre says, but it’s expected to remain at that level for the next 24 hours.
Four Charlton properties are at risk of above-floor flooding with SES and CFA crews urgently sandbagging to protect them.
A further 80 homes have been door-knocked with people living in low-lying houses advised to evacuate.
Elsewhere in Victoria, three properties have been sandbagged in Panmure with residents facing possible flooding on Sunday from Mount Emu Creek.
In Allansford, also in the southwest, three properties are threatened by the Hopkins River on Sunday or Monday.
Bureau of Meteorology senior forecaster Peter Newham says a rainband will move into the state’s west overnight and extend eastwards during Sunday.
It will likely bring five to 10 millimetres of rain in Victoria’s west and up to 20mm in the east.
Some sections of the northeast could receive 40mm but fortunately they’re only experiencing minor flooding at present.
“Monday is a bit of a break day between fronts,” Mr Newham told AAP on Saturday, suggesting Tuesday’s rain could see five to 20mm fall across Victoria.
Sections of the Great Ocean Road remain closed “due to severe structural damage to the roadway”, authorities say, with further landslides possible.
Residents between Lorne and Skenes Creek are safe but can’t use the road to access their homes.
Floodwaters claimed the life of an elderly farmer whose body was discovered in a Wallacedale dam on Friday.
The 84-year-old man, named by media as Frank Bell, had been missing since Wednesday after his ute was found swept away in the dam.
The state government has announced up to $1300 per person in disaster assistance to help cover immediate needs and up to $32,500 to help with the clean-up and rebuild.
Victorian Emergency Services Minister James Merlino and Federal Justice Minister Michael Keenan on Saturday announced further disaster relief for 22 flood-impacted regions.