Projects
Caboolture West Sewer Gravity Mains
The Caboolture West Sewer Gravity Mains project is a key Unitywater infrastructure investment supporting the long-term development of the Caboolture West and Morayfield South growth areas within the City of Moreton Bay.
The project involves the design and construction of a major DN1400 trunk gravity sewer connecting the Waraba Sewage Pump Station to the South Caboolture Sewage Treatment Plant, enabling future servicing of a population of approximately 40,000 equivalent persons through to 2041 and beyond.
Project information
- Project Owner
- Unitywater
- Stage
- Tender
- Location
- Caboolture / Morayfield, QLD
- Capital Cost
- Not disclosed
- Year
- 2026
Scope
The project comprises the construction of approximately 2.75km of DN1400 gravity sewer, delivered via a combination of open trench and trenchless construction methodologies.
Key elements of the scope include:
- Installation of DN1400 GRP gravity sewer mains
- Construction of maintenance holes and connection structures along the alignment
- Open trench excavation and installation works at depths generally ranging from 3m to 6.5m
- Integration of branch sewer connections and diversion of existing reticulation networks
- Decommissioning of existing sewer infrastructure where required
- Testing, commissioning, and handover of new assets
The works are delivered across multiple separable portions, incorporating complex staging, interface management, and coordination with trenchless construction activities and existing infrastructure.
Construction activities include excavation, dewatering, trench support systems, pipe installation, traffic management, environmental controls, and full reinstatement of affected areas.
Service Provided
Civil Project Partners provided detailed cost estimating services to support the tender phase of the project.
This included preparation of cost estimates for large-diameter gravity sewer installation works, incorporating open trench construction, deep excavation, maintenance hole construction, and interface risks associated with existing services and constrained access corridors.
CPP also supported methodology reviews and scope alignment to ensure accurate pricing across multiple work packages and staging scenarios.
