Transport Minister and Tauranga MP Simon Bridges welcomed the news that work was set to start on the project.
"The project will connect to the recently opened $455 million Tauranga Eastern Link and once finished will reduce congestion, improve safety by separating local and state highway traffic, and support economic growth in the region by improving the route to the Port of Tauranga.
"It is exciting to see another transport project get underway that will support Tauranga and the wider Bay of Plenty's economic and population growth for decades to come.
"Once it is finished it will make a real difference to people's travel."
New Zealand Transport Agency Bay of Plenty highways manager Niclas Johansson said the railway relocation work was the first phase of the State Highway 2 project.
"The project team is working closely with KiwiRail on the enabling works, which involves relocating the East Coast Main Trunk railway line to the west of Owens Place," Mr Johansson said.
"The relocation work will be carried out in two stages. Fulton Hogan have been awarded the $4.1 million contract to carry out the first stage which involves preparing the site of the new railway line.
"Fulton Hogan will be doing the earthworks and drainage as well as building a noise wall and two retaining walls alongside the site of the new railway."
Mr Johansson said the initial work would start this week and is expected to take five to six months.
Once finished, KiwiRail will start on stage two of the relocation, setting ballast, installing signals and laying new track.
The railway line was expected to be relocated by late 2016, with work on the second phase of the project set to start in 2017, following the tender process.
Once complete, the Baypark to Bayfair Link Upgrade will reduce congestion and improve safety by separating local and state highway traffic, and encourage economic growth in the region by improving the route to the Port of Tauranga.
The Transport Agency aims to have the flyovers open to traffic in 2020.
The Baypark to Bayfair Link upgrade will connect to the $455 million Tauranga Eastern Link, completing what is known as the 'Eastern Corridor' for the Bay of Plenty.
The Eastern Corridor provides an efficient and safe route to the Port of Tauranga, encouraging economic growth and productivity in line with the strategic direction set by the 2015 Government Policy Statement (GPS) on land transport.
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