Melbourne’s SRL East tunnelling packages go to market

(Photo by Zichuan Han from Pexels)

The Victorian Government’s Suburban Rail Loop Authority has put two major tunnelling packages for the Suburban Rail Loop East (SRL East) project in Melbourne out to market, following the completion of pre-qualification on March 25.

The Suburban Rail Loop is a new 90-kilometre rail line that will connect Melbourne’s metropolitan train lines from the Frankston Line in the east to the Werribee Line in the west. The first stage of the Suburban Rail Loop program is the south-east segment from Cheltenham to Box Hill.

Work packages C and D, two of the total of seven work packages constituting the SRL East project, comprise a fully-tunnelled 26-kilometre metro corridor between Cheltenham and Box Hill in Melbourne’s east.

The line will include six stations, including new interchanges with existing heavy rail stations at Cheltenham, Clayton, Glen Waverley and Box Hill, with new stations at Monash and Burwood.

The first tunnelling package – Package C – will be the longest in Victoria’s history, delivering around 16 kilometres of twin tunnels between Cheltenham and Glen Waverley.

The second tunnelling package – Package D – will complete the SRL East corridor with tunnels from Glen Waverley to Box Hill.

Up to ten tunnel boring machines (TBMs) will be used for SRL East – each custom-built to suit the local ground conditions. The Metro Tunnel used four TBMs, while eight were used for the dual 21-kilometre tunnels on London’s CrossRail project.

The number of TBMs will speed up the tunnelling process, with launching sites planned for three locations: Monash, Heatherton, and Burwood.

Expressions of Interest open this week for the two tunnelling packages and will close by mid-2022. Up to three bidders will be shortlisted for participation in staggered Request for Proposal phases.

The bidders will compete for Package C, with a contract expected to be awarded by the end of 2023. The remaining two unsuccessful bidders for Package C will then compete for Package D, with that contract expected to be awarded in the third quarter of 2024.

This package of works will also include safety cross passages between the tunnels, station boxes at Clayton and Monash, and tunnel entrances and exits at the stabling facility.

Laing O’Rourke was officially awarded the circa $500 million Initial Works and Early Works package for SRL East project in November last year.

Initial construction on the project, including minor road modifications, utility re-location and ground improvement works, will start in coming weeks, with tunnelling expected to kick off in 2026.

When completed in 2035, SRL East will connect major employment, health, education, and retail destinations in Melbourne’s east and southeast. Trains will carry 70,000 passengers a day, with 8000 jobs set to be supported by the project.