“It would be fair to say that passion is not the first emotion that springs to mind when you think about a sewer, but it was passion for a safer means of accessing the shafts at the Amaroo Main Sewer that created the motivation, which lead to the innovative solution developed for shaft entry at this project.
A safe and secure means of accessing a shaft during both the sinking operation and when it has reached its final depth has been an issue that has bedevilled the tunnelling industry.
When the drop to the bottom to the shaft floor is over 20m and you know that you will be repeatedly climbing in and out, it is crucial to make sure you get it right. The Amaroo Team had the collective experience to realise that nothing previously employed satisfied all the safety criteria. The project’s Design Manager together with the Production Team came up with an enclosed ladder system that fitted the tight constraints of a sewer shaft while offering protection to the worker accessing the shaft floor and when slinging material in and out of the shaft. The system was hung from the shaft collar and all extension pieces were installed from the security of the surface platform. It could be easily removed from the shaft during blasting operations or remain as the primary means of access for the pipejacking crew. In other words, it really did tick all the boxes.
The mark of a great idea is when others want to use them; all the ladders are now being relocated to new John Holland projects.”