As of Monday afternoon, the SES had received 2391 calls in Knox and 1600 tasks were still outstanding.

Municipal emergency response co-ordinator, Senior Sergeant John Hess, said calls from Knox made up about 50 per cent of the SES's statewide response.

The suburbs hardest hit were Wantirna, Ferntree Gully, Lysterfield and Rowville.

Senior Sergeant Hess said he expected another spike in calls as people returned home after the Labour Day long weekend.

"There's a lot of unoccupied homes, so we wouldn't be surprised if we get a spike in people seeking assistance."

He said the SES had focused heavily on the Lysterfield area on Sunday before concentrating on the Wantirna area on Monday.

"We've got 23 units in the field as we speak, including nine units from South Australia."

Also helping Knox crews in the clean-up were teams from Tallangatta, Corio, Frankston, Kerang, Mildura, Bellarine, Kinglake and Seymour .

CFA units did damage assessments and visited premises to see how the SES should prioritise tasks. The Salvation Army provided food and drink to crews out on the road.

Senior Sergeant Hess advised residents to have their roofs checked for any damage.

He said the SES would attend to all tasks in the next few days, but it could take weeks for residents to clean up all the damage. A number of trees had fallen, but they would only be attended to by the SES if they presented a danger to the community.