Australia’s Queensland state water company, Seqwater, on July 9 awarded the first construction contract for the approximately $165 million Toowoomba-to-Warwick pipeline to a joint venture between CPB Contractors and NACAP.
Construction on Stage 1 of the long-planned water infrastructure project is expected to begin in late 2026 on the first segment of the 69-mile pipeline connecting the outback Queensland cities of Toowoomba and Warwick, about 90 minutes west of Brisbane.
The project is expected to support around 400 construction jobs.
“Seqwater is delivering the project on behalf of the Queensland Government to strengthen water security for Toowoomba and protect the project corridor that could deliver long-term benefits for the Southern Downs,” Seqwater CEO Emma Thomas said in announcing the contractor award.
The project plans provide for two reservoirs, two pumping stations and two future dam sites. The route will predominantly cross state and local highway corridors and will use cemented ductile iron-lined polyethylene, mild steel and polyethylene pipes with diameters ranging from DN125 to DN600. The alignment includes 64 river crossings and seven railway crossings.
Most of the pipeline will be installed using conventional open-trench construction, although trenchless methods, including horizontal directional drilling and pipe jacking, are planned at major road, rail and waterway crossings to reduce surface disruption.
The pipeline concept originated after severe drought left Leslie Dam, Warwick’s main water source, at critically low levels in 2020.
Looking for quick answers on construction and engineering topics?
Try Ask ENR, our new intelligent AI search tool.
Ask ENR →
Seqwater’s Toowoomba-to-Warwick pipeline will run approximately 69 miles between Toowoomba and Warwick in Queensland, Australia. Stage 1 will build the northern segment to Greenmount, with a future extension continuing south to Warwick.
Map courtesy of Seqwater
According to Seqwater’s Public Environmental Report, the trail traverses expansive clay soils for much of its northern section before transitioning to sandstone formations further south. Project planners identified shallow basalt and sandstone, steep terrain, major waterway crossings and localized areas of ground instability as the main geotechnical challenges, including 16 mapped landslide hazard zones totaling less than a mile of alignment.
The federal environmental review was based on the work of engineering consultancy SMEC, environmental consultancy Jacobs and ecological consultancy Ecosure.
The state revised the project’s delivery strategy earlier this year, splitting construction into two phases after updated water security assessments found the immediate drought risk had been reduced.
“By advancing the pipeline in stages, we are balancing investment with long-term water security and ensuring regional infrastructure keeps pace with future growth, demand and opportunities,” Queensland Water Minister Ann Leahy said.
Stage 1 will deliver the pipeline to Greenmount, about 16 miles south of Toowoomba, while the remaining 40-mile section from Greenmount to Warwick will proceed to a future government decision based on regional water security needs.
Although the construction contract for the first stage has been awarded, the project remains subject to Australian federal environmental review under the Environment Protection and Biodiversity Conservation Act before work can begin.
During the public comment period, six submissions from individuals and community groups raised concerns about potential effects on koala habitat, threatened species, habitat connectivity and road vegetation.
Seqwater said successive alignment reviews and construction changes, including ditchless waterway crossings and route adjustments to avoid sensitive habitats, were made to reduce environmental impacts.
Construction is expected to take approximately 30 months, subject to work package sequencing, timing and regulatory approvals.
