The detailed underground path of Suburban Rail Loop (SRL) East between Cheltenham and Box Hill shows the varied topography of Melbourne's middle suburbs.
Constructing twin 26km tunnels underneath a dense urban area presents a unique engineering challenge, requiring meticulous planning to minimise the impact on homes and businesses.
Tunnelling is complex because of the different types of ground and rock formations, and the existing buildings and infrastructure serving the thriving and vibrant suburbs above.
The underground path of SRL East will pass through varied topography
The tunnel will mostly range between 20m and 40m below the surface, with the deepest point up to 60m below ground under Riversdale Road, Burwood. Cheltenham’s station will be closest to the surface, at just 16m underground, and the station at Monash at 24m underground will be the deepest. Comparatively, Melbourne’s City Loop station platforms are about 30m underground, with Parliament station 39m below the city streets.
The tunnelling route has been planned using a myriad of geo-technological engineering methods – from the high tech through to traditional drilling. A total of more than 10km below ground has been drilled so far along the SRL alignment between Cheltenham and Box Hill, to gather information about local ground conditions.
Engineers conducting pre-construction survey work in Box Hill have also used the innovative approach of seismic testing to test how vibration travels through the ground. This method was used at several locations including Box Hill Gardens, Station Street, Severn Street and Thames Street.
SRL is Victoria’s largest ever public transport investment, providing vital transport connections through Melbourne’s middle suburbs and opening up access to key education, health and shopping destinations for many thousands of Victorians.
SRL East between Cheltenham and Box Hill will be open by 2035, with a turn up and go service delivering better transport connections, and better access to jobs, education and health services. Within a year of opening, around 70,000 passengers will use the service every day.
Construction starts next year, creating up to 800 early direct jobs.