Northern Tunnel Portal - Sewer main relocation

From December 2020 for approximately four months, an underground sewer main located under the rail corridor at Normanby and within Victoria Park will be relocated approximately 300 metres east to enable construction of the Cross River Rail Northern Portal.

The new sewer main will be installed using two construction methodologies – microtunnelling and open cut trenching.

Microtunnelling will involve installing a new sewer main beneath the operating rail corridor and Inner City Bypass (ICB). Open cut trenching will be used to install the section of new sewer main along the existing Victoria Park pedestrian and cycle path. For more information about this methodology please refer to one of the links below:

Construction vehicles will use existing access roads and footpaths to reach work areas within Victoria Park, north and south of the ICB. Traffic controllers will manage vehicle movements within the park and interface with the public where required.
 

What to expect

  • Increased construction activity in the area with potential for an increase in noise, dust, vibration and workers
  • Work is subject to relevant approvals and suitable weather conditions
  • Construction impact mitigation activities such as water carts, water suppression and installation of fencing
  • Increased truck movements. Traffic control will be in place to assist where required
  • Temporary pedestrian and traffic changes. Please see below for more information
  • Standard construction times are 6:30am to 6:30pm, Monday to Saturday, however work will occur outside of these hours due to traffic permits, safety requirements and construction methodology.

 

An underground sewer main located under the rail corridor at Normanby and within Victoria Park will be relocated approximately 300 metres east. Construction access will be via existing footpaths and access roads in Victoria Park.
 

Site establishment including works areas

Victoria Park; north and south of the Inner City Bypass (ICB)

During December 2020, the following works will occur:

  • Delivering plant and equipment
  • Trimming vegetation along the haulage route within Victoria Park
  • Removal of three juvenile paperbark trees in Victoria Park on the northern side of the ICB
  • Minor earthworks to prepare the work areas and access routes
  • Night work on Gregory Terrace to prepare for the shared user path diversion
  • Installing temporary fencing around work areas and access routes
  • Intermittent stoppages of the shared user path may be required between 9am and 4pm to mobilise vehicles and equipment to the work areas.

 

Open cut trenching

Along Victoria Park shared user path

From December 2020 to late January 2021, the following works will occur:

  • Identifying existing underground services with vacuum excavation trucks
  • Cutting and excavating a trench approximately 300 metres along the shared user path and within Victoria Park
  • Installing the new sewer main segments with mobile cranes
  • Backfilling the trench and reinstating the pedestrian and cycle path
  • Closure of shared user path and installation of temporary cyclist facilities on Gregory Terrace and College Road from December 2020 to late January 2021. More information about the diversion will be distributed prior to the closure.

 

Microtunnelling

Under the rail corridor and ICB

From January to February 2021, the following works will occur:

  • Excavating and constructing concrete shafts
  • Installing the boring machine into the concrete shaft on the southern side of ICB using mobile cranes
  • Using the boring machine to excavate the underground sewer alignment
  • Using hydraulic equipment to push the pipe through the ground behind the boring machine
  • Removing excavated material with trucks.

What is microtunnelling?

Traditional open-cut trenching involves digging a trench, laying pipe and backfilling the trench.

Microtunnelling does not require a trench. Instead, a small boring machine will be used to dig an underground path, after which specialised hydraulic equipment is used to push lengths of pipe through the ground.

The boring machine will be selected specifically for the existing geological conditions in the area.
 

Decommissioning and reinstatement

Victoria Park north and south of the Inner City Bypass (ICB)

From February to March 2021, the following works will occur:

  • Plugging and filling redundant sewer pipes
  • Removing all equipment and materials
  • Reinstating work areas

Victoria Park shared user path diversion

A temporary diversion of the Victoria Park shared user path, behind Brisbane Girls Grammar School, will be required from December 2020 until late January 2021 to enable open cut trench excavation. Temporary cyclist facilities will be built on Gregory Terrace and College Road prior to the closure.

More information about the diversion will be distributed prior to the closure.

If you want to know more, all of this information is available in PDF form: