The deck of Sunderland's New Wear Crossing could start making its way across the river this weekend.
The bridge team is carrying out final preparations in readiness to launch the 300m deck from the south side of the river to the north.
If weather conditions are suitable, the process could begin on Sunday afternoon.
The initial phase will be particularly slow as the blue steel temporary nose of the deck is guided carefully through the 100 metre tall central pylon.
While people are unlikely to actually see the bridge deck moving, due to the controlled pace of the hydraulic jacks controlling the launch, its progress will be visible over the course of time as the steel and concrete structure moves gradually towards the north embankment.
The operation is expected to take at least two days to complete, and will be dependent on weather conditions.
Once in place, the deck will span from where it has been assembled on the south side of the river in Pallion to the north side in Castletown, and will require a further 40m section to be constructed over the summer months on the north side in order to complete the full length of the bridge.
Sunderland City Council leader Coun Paul Watson said: "It will be very exciting to see the bridge deck take its final position over the River Wear.
"With every major milestone we pass, the new bridge comes to life a little bit more, and having the deck across the river will really give us an indication of what the New Wear Crossing will do for Sunderland and the positive impact it will have on the landscape.
"It will inject investment, jobs and pride into our city and will be the catalyst for regeneration and development along the riverbank in Pallion.
"Exciting times lie ahead for Sunderland."
The New Wear Crossing is phase two of the Sunderland Strategic Transport Corridor, which is a five-phase plan to improve links between the A19 and Sunderland City Centre and the Port of Sunderland.
Since construction got underway in May 2015, much of the work has centred around building the cofferdam and pylon foundations within the riverbed, constructing the approach roads on the south side, and assembling the bridge deck.
Roadworks have also been carried out on both sides of the river to prepare the current road network for the opening of the bridge in the spring of 2018.
However, in recent months, work has stepped up on the north side of the river, where the northern approach road and abutment are being constructed, and the new alignment of Hylton Park Road is being developed.
The work is being carried out by Farrans Construction and Victor Buyck Steel Construction, which formed a joint venture to deliver the project on behalf of Sunderland City Council.
Stephen McCaffrey, Project Director for FVB Joint Venture, said the project was progressing well and was on track to open next spring.
He said: "We may be in a position to start the initial bridge deck launch on Sunday afternoon, which will allow us to test that all the equipment is operating as expected before embarking on the bulk of the launch on Monday.
"If the weather conditions aren’t right, however, we may need to start on Monday morning instead.
"At 300 metres long and weighing 4,750 tonnes, the deck is a substantial structure so moving it out across the river will be a very slow and steady operation. It has been in the planning for a long time, and has been calculated to the nearest millimetre, so we will be monitoring it throughout to ensure it progresses in the way we expect.
"While people may not actually be able to see the deck itself moving, as it does so very slowly, over time they will see progress. We don’t expect it to be finished until Tuesday or Wednesday, at the earliest, but once complete, I’m sure people will feel that the bridge is visibly taking shape over the river."
The impressive 100metre pylon was raised into position in February during a two-day operation. It is now secured to the foundations within the riverbed and is free-standing.
Scaffolding has been attached to the top of the pylon to enable the cable stays to be fitted during the summer, which will be attached to the deck and gradually stressed to take the weight of the bridge later this year.
After that, the blue steel temporary supports holding the deck will be removed.