The bridge, which links Moonee Valley with the City of Maribyrnong over the Maribyrnong River, was closed in June 2008 when it was deemed structurally unsafe.

Due to its highly unusual design, the opinion of a specialised timber bridge expert from Sydney was sought.

But planning, testing and preparation works have dragged on for more than a year.

The estimated budget for the bridge's repair has blown out to more than $400,000.

Now 21 months after the bridge was closed, Moonee Valley mayor Shirley Cornish said works should finally be completed by April.

The bridge is believed to have the longest single span laminated timber beams in the world, which has added to the complexity of repair works.

Cr Cornish said drilling and inserting strengthening rods through the main arch beams of the bridge and attaching a cladding frame was under way and would be completed by next week.

"Painting the section of the bridge over the river will commence next and will take approximately four weeks. Following that the aluminium cladding will be installed onto the frames and be completed in April."

Cr Cornish said engineers G&G Engineering (Aust) Pty Ltd had encountered setbacks along the way with sections of deteriorated timber having to be repaired or replaced.