ABSTRACT
As in every major city, the infrastructure of Melbourne has demanded tunnels for water supply, sewerage, telecommunications and transport. The Board of Works tunneling program essentially developed as a specialist dayworks operation with there own dedicated crews which started in the 1960's and is still currently proceding, though at a lesser level of activity. The larger sewers for Melbourne's original system were located in the soft ground close to the Yarra River mouth area and were constructed by various contractors using tunnelling methods. Another project of interest and importance was the lowering of the Hobsons Bay Main Sewer which involved the construction of a sewer tunnel under the Yarra River at a lower level than the existing main so that larger ships could access Melbourne's docks. Elaborating on the tunnel monitoring referred to earlier in this section, the programme implemented for the melbourne underground rail loop project was the most extensive for tunnels constructed in the Melbourne region.
