Scope:
This project involved the installation of a DN 300mm PVC sewer main and three DN 1200 manholes, including two micro-tunnel bores at 80 meters each. The sewer main was installed in water-charged sandy ground at depths of up to five meters. The scope also included the installation of a temporary bypass and three connections. Additionally, 15 meters of the existing 225mm sewer main was replaced at the West Botany and President Avenue intersection during a 56-hour shutdown. This work included concrete encasement and bypassing of the main throughout the process. The project also involved raising five manholes during night shifts.
Total Length: 185 meters
Key Challenges:
Key challenges included replacing 15 meters of a live sewer main in the middle of a busy intersection during a 56-hour shutdown, managing a constantly evolving site with multiple traffic switches, and excavating up to 5.5 meters in water-charged ground. The project also faced complications with filled ground and unexpected findings, working in close proximity to leachate barriers, managing traffic, and dealing with bore shaft issues caused by water ingress.
Result:
Road and Rail Excavations successfully delivered all scope and packages on time and within budget, maintaining high standards of quality and safety throughout the project. Innovative measures enabled us to excavate three bore shafts in water-charged ground at depths of 5.5 meters. Through close collaboration with our shoring and pumping suppliers, we effectively overcame challenges such as groundwater and running sand.
