UPDATE: The Mary River has peaked at 4.3m on Tuesday morning, lower than the expected 5m flood height.
The swollen banks of the river are now receding and Fraser Coast Mayor Gerard O'Connell said Maryborough was getting back to "business as usual".
Fraser Coast Regional Council crews will reinstall the rails of the Lamington Bridge this morning and hope to have it open on Monday afternoon.
Cr O'Connell praised the preparedness of the Local Disaster Management Group and residents and thanked volunteers for their work.
EARLIER UPDATE: Floodwater levels on the Mary River are slowly easing upstream and the waterway probably peaked about 5m in Maryborough in the early hours of Tuesday, the Mayor says.
"I think we're probably right," Fraser Coast Regional Council Mayor Gerard O'Connell said.
"It's an inconvenience at Lamington Bridge," he said.
He said engineers would assess the closed bridge on Tuesday but he hoped there hadn't been any damage to prevent the rails being replaced so it could be reopened.
Cr O'Connell said Granville had not been cut off although it looked like some debris was wedged under the Granville Bridge.
He said Maritime Safety Queensland would probably wait until floodwater levels had dropped and the flows were down before giving the okay for vessels to return to the river system.
"I think the emphasis is going to be on the rural areas - checking roads and surfaces," Cr O'Connell said.
EARLIER: Department of Main Roads engineers hope to assess the Lamington Bridge on Tuesday before rails are re-installed and the road reopened.
Maryborough has again avoided the worst of Cyclone Marcia with floodwaters expected to peak at only 5m.
The revised figure was predicted by the Bureau of Meteorology after their flood modelling was completed for the Mary River catchment.
BOM hydrologist Andrew Preece said the peak of the flood was likely to begin falling after 12.30am on Tuesday.
It made the prediction after analysing water levels in the creeks and systems feeding into the Mary River.
"I think it will be tied into the high tide tonight," he said.
"We can expect to see the river levels start to fall then."
The Lamington Bridge remained closed on Monday despite the lower predictions after the rails were removed on Sunday morning as an "appropriate precaution".
However Fraser Coast Mayor Gerard O'Connell said the bridge would not be opened until engineers had deemed it structurally safe.
Massive logs and rubbish including an oil drum have been wedged against piles on the Granville bridge by the rapid river.
Cr O'Connell said because Maryborough was considered a port, any debris removal would be a Maritime Safety Queensland issue.
Because of the submerged objects boaties have been advised that any navigation in the upper parts of the Mary River near the Marina be done in daylight hours.
The Fraser Coast Disaster Management Centre is expected to be closed on Monday after monitoring the cyclone and flood situation since Thursday last week.
At Tiaro, the flood level peaked at 13m about noon on Monday.