When called in to partner on a trenchless pipeline installation in Townsville, Queensland, Edge Underground was given four weeks to complete the project. However, armed with some of the best microtunnelling equipment in the industry, and collaborating with a company that knew how it worked, Edge Underground exceeded everyone’s expectations and set a new benchmark for the industry when it completed the first stage of works in only six days.
In mid-2019, Edge Underground was subcontracted to help complete the Northwood Sewer Project in Townsville, partnering up with local contractor NQ Excavations.
Stuart Harrison, Managing Director at Edge Underground, said the team was called in to complete a range of different pipeline diameters that all needed to be installed on grade.
“We went about setting somewhat of a new benchmark in these diameters. The first part of the project we completed was about 180m, comprising five separate lines of sewer pipeline. Three of the setups were 610mm diameter bores, and two were 510mm,” Mr Harrison said.
“The lines were unique in that the pipe selected was really not a structural pipe, which made it unique in itself. It was a sewer max pipe, which isn’t known for being used in a jacking environment.
“But the ground we were working in was incredibly stable, so we knew that we’d be able to push the pipe through the bores without doing any structural damage, and save a lot of money.”
The works were completed in six days.
“It’s something that I don’t think anyone considered was possible at the time we started.
“However, some of the unique aspects of the way we do our work with the AXIS system gives us an opportunity to create some significant cost savings. That’s exactly what we did here,” Mr Harrison said.
Preparing the site in advance
A key factor that contributed to the quick completion of the works was the existing working relationship between Edge Underground and NQ Excavations, which ensured all site preparation works were completed in advance.
“The problem that we often have is that we’ll go to a job site and we’ll be starting to do our job, assuming the contractor is organised and they’ve got invert grades and lines, and shafts prepared in advance,” Mr Harrision said.
“At the end of the day, we need to have the next line ready to go. So we’ll get to a point where we’re running quicker than they can prepare shafts.
“I think that’s probably something that surprises people. Often their experiences might be that they’re going to take a fair amount of time to prepare a shaft, and they’ve got time because the borers are going to take a while.”
Mr Harrison said this was not the case with NQ Excavations as they had worked together on a number of jobs in the past, and knew exactly what Edge Underground needed and how quickly the team could put pipe in the ground.
“They knew what we needed, so upfront we had shafts and lines prepared in advance. Inverts and all the critical information we needed was already prepared,” Mr Harrison said.
“It’s like working with any contractor, the first time we went up to Townsville there was learning and building contacts with NQ Excavations. But now they know what we need and we know how they like to run, which made us really efficient on this project.
“To be honest, I think we may be making a few more records on the next part of the job. Especially if the site can be prepared in advance.”