Project Description

Client:  Pasminco Cockle Creek Smelter Pty Ltd
Authority:  Hunter Water Corporation
Contractor:  Patroy Enterprises
Location:  Main Road, Boolaroo (Lake Macquarie), NSW
Date: 2012
Value: $1M

Through 2011 – 2013 a new intersection was designed and constructed at the intersection of TC Frith Avenue and Main Road, Boolaroo.

The intersection and ancillary roadworks impacted several major utility services including three regionally significant trunk watermains. Two of the mains service the western side of Hunter Water’s operation area and form part of the backup water service plan for the Central Coast.

The watermains were relocated and replaced in the vicinity of the roadworks to ensure ongoing successful operation to Hunter Water’s water supply network.

GCA's Involvement

GCA were responsible for investigations, concept and detailed engineering designs and specifications for replacement / relocation of:

  • A total of 180m of 500mm Cast Iron watermains (original construction around year 1956)
  • 170m of 300mm Cast Iron watermain (originally constructed in year 1933)

Throughout the design process we focused keenly on anticipating the construction method and developing design details and specifications that would result in minimal shutdowns for the existing watermains.

The shutdown time and risk to Hunter Water’s supply base was ultimately minimised through development of:

  • Specialised connection details
  • Early works components that could be completed initially and left in-place for concrete to cure without additional forces whilst the watermains remained in service
  • A variety of materials (Polyethylene, Mild Steel, Ductile Iron) with consideration to the high operating pressures and with consideration to the individual construction considerations in each part of the project site
  • Specifying special pipe trench details and structural protection measures where warranted.

Our relationship with Hunter Water staff was also key to the success of the project. Through this we were able to meet with Hunter Water to discuss network operation issues and the anticipated network shutdown procedure and issues that would need to be addressed.

The project was successfully constructed without any impacts on Hunter Water’s customer base.