AT is going to start positioning the beams for the Eastern Busway over the Tamaki River on Monday.
There are four beams and each one is dropped in and connected to the section behind it. Each push of the bridge is around 50 metres and takes three days.
The steel bridge beams were delivered to the construction site earlier in the year and are the largest single steel beams ever to be fabricated in New Zealand.
The new busway bridge is more than 200 metres in length and weighs more than 100 tonnes.
The bridge runs alongside the existing Panmure Bridge and will include new cycling and walking paths and lookout platforms.