Southern Rural Water has kicked off works to replace a key tunnel that will improve water reliability for the Macalister Irrigation District.
After leaving Lake Glenmaggie, water is split between the Main Northern and Main Southern Channels to keep supply consistent across Victoria’s most productive irrigation region.
Along the Main Southern Channel, two key tunnels carry water through rocky terrain. Tunnel 5 transports 40% of the channel’s total flow, while Tunnel 6, running parallel to it, carries the remaining 60%. Together, they play a vital role in maintaining the region’s water delivery.
Constructed in the 1920s with 2.4-meter diameter cast in situ concrete pipes, Tunnel 5 was engineered to navigate the difficult rocky terrain. While it has reliably served the region for decades, it is now reaching its lifespan.
This winter, we’re replacing 140m of the downstream end of Tunnel 5 with modern materials and construction techniques to ensure long-term reliability. The 80m upstream end of tunnel 5 is scheduled for replacement next year.
This tunnel upgrade is just one part of our wider winter works program. We’re also busy automating customer outlets, replacing old regulators, tackling weed control, fixing erosion, and doing general maintenance across the network to keep things running smoothly.
By scheduling works during the winter shutdown, we ensure everything is ready to go once the irrigation season begins in August.