The majority of properties in Donvale, an outer eastern Melbourne suburb, are currently unsewered, but a project by Yarra Valley Water is using microtunnelling to construct a four kilometre branch sewer and connect residents to the system.
MFJ Constructions won the principal contract for the project and Pezzimenti Trenchless have been contracted to install the Donvale Branch Sewer, which forms the backbone of the Donvale Sewerage Project.
The project aims to create a better sewerage system for the suburb, and enable leaking septic tanks to be decommissioned.
Pezzimenti Trenchless are using microtunnelling to install a total of 4,470m of Hobas Jacking pipes at depths between 810m, with 1,500m of pipes having already been installed.
Microtunnelling is being used to avoid major excavations that would disrupt the local community and add costs to the project’s delivery.
The Donvale Sewerage Project also involves the installation of reticulation sewer pipes and property connections, which will connect to the branch sewer once completed.
Pezzimenti Director Joe Pezzimenti said the project has several challenging elements, including difficult ground conditions, that had to be taken into consideration.
“The sites have extremely hard siltstone – up to 40mpa – with Quartz pockets, and there are also challenges with groundwater and access to sensitive council land and private properties,” Mr Pezzimenti said.
“We have also had to drill under the Mullum Mullum Creek twice and we plan to do a few more crossings there, so there has been a lot of things that we have successfully juggled to get the project moving forward.”
Work on the branch sewer began in December 2015 and is scheduled for completion by June 2017.