Jacobs-Stantec JV to Deliver Greater Western Water Infrastructure
The selection of the joint venture between Jacobs and Stantec to deliver Greater Western Water’s capital infrastructure programme marks a major milestone in Victoria’s utility planning and urban development. Covering a massive service footprint of 3,700 square kilometres across Melbourne’s rapidly growing western corridor, this five year capital delivery programme is designed to meet the water and sewerage demands of a regional population projected to double by 2050. For land developers, local councils, legal practitioners, and environmental consultants, the scale of this infrastructure expansion represents both a significant catalyst for economic growth and a complex exercise in land-use coordination and regulatory compliance.
What makes this appointment particularly notable for the environmental services sector is the deliberate and early integration of critical technical disciplines into the master planning and option assessment phases. Contaminated land investigations, hydrogeological assessments, and discharge water quality analyses are not being treated as late-stage compliance activities. Instead, they are embedded directly into the initial engineering design process. This structural shift moves away from the historical, reactive model of linear infrastructure delivery, where ground contamination and groundwater issues were often only identified during excavation, resulting in severe project delays and significant cost overruns.
By characterising the subsurface environment before finalising pipeline alignments and asset locations, the joint venture is establishing a new standard for infrastructure delivery. In a region characterised by complex volcanic geology, historical industrial land uses, and sensitive ecological receptors, this proactive approach mitigates a wide array of environmental and financial risks. It provides a structured framework that other infrastructure authorities and private developers can look to as a model for de-risking major capital works in a highly regulated landscape.
Geotechnical and Contamination Challenges in Melbourne’s West
To understand the technical complexity of the capital programme, one must examine the specific geographic and environmental attributes of the 3,700 square kilometre service area. The corridor extends from the inner western suburbs of Melbourne through to the outer urban boundaries of Melton, Wyndham, and Bacchus Marsh. The geology of the Werribee volcanic plains consists predominantly of Newer Volcanic Group basalt, which presents distinct geotechnical and hydrogeological challenges. Soil profiles in these areas often feature heavy clay soils overlying fractured basalt rock, which can act as preferential pathways for groundwater flow and contaminant migration.
The environmental scope of the five year programme requires a systematic, phased investigation methodology to address potential contamination hazards across this vast area. Environmental practitioners must identify and evaluate a diverse range of historical land uses that may have left legacy contamination. Identifying these issues early allows the engineering design teams to optimise pipeline alignments, potentially bypassing highly contaminated zones altogether. Specific historical land-use hazards within this region include:
- Historical agricultural activities where organochlorine pesticides and heavy metals were widely applied.
- Industrial zones with potential chlorinated hydrocarbon and petroleum hydrocarbon impacts.
- Unregulated historical landfills and waste-disposal areas containing asbestos-containing materials.
Hydrogeological characterisation is another key technical component of the initial planning phase. In the fractured basalt aquifers of Melbourne’s west, groundwater depth and quality can vary significantly. Early stage hydrogeological assessments are critical for identifying shallow water tables that will intersect utility trenches, necessitating construction dewatering. By conducting detailed aquifer testing and groundwater quality sampling, the joint venture can establish accurate baseline conditions. This includes testing for emerging contaminants of concern, such as per- and polyfluoroalkyl substances (PFAS), which are highly mobile in groundwater and require specialised management protocols under Victorian environmental guidelines.
Furthermore, early discharge quality analysis is vital for designing effective dewatering management systems. When groundwater must be extracted during pipeline installation, the water must be managed in accordance with strict environmental discharge standards. If the groundwater is found to contain elevated concentrations of metals, nutrients, or synthetic organic chemicals, it cannot be discharged to local surface waters without treatment. Early characterisation allows the project team to evaluate treatment technologies, obtain necessary disposal agreements with sewer authorities, or design reinjection systems well before construction contractors mobilise to the site, thereby removing a frequent source of project disruption.
Alignment with Victoria’s General Environmental Duty (GED)
The proactive environmental strategy adopted by Greater Western Water and the joint venture aligns directly with the regulatory framework established by the Victorian Environment Protection Act 2017, which commenced on 1 July 2021. The cornerstone of this legislative framework is the General Environmental Duty (GED), which places a positive obligation on all individuals and corporations to eliminate or minimise risks of harm to human health and the environment from pollution and waste so far as reasonably practicable. In the context of large-scale infrastructure projects, demonstrating compliance with the GED requires proactive risk assessment and management systems. Waiting until construction to assess soil and groundwater contamination is no longer legally or operationally defensible under the new legislation.
References and related sources
How iEnvi can help
iEnvi provides specialist consulting services relevant to this topic. Our team includes CEnvP Site Contamination Specialists with experience across contaminated land, groundwater, remediation, ecology, and regulatory compliance.
- iEnvi contaminated land services
- iEnvi remediation and validation services
- iEnvi expert services and independent review services
This is an iEnvi Machete news summary. Prepared by iEnvi to summarise the source article for contaminated land, groundwater, remediation, approvals and site risk professionals.
Published: 17 Jun 2026
Need advice on this topic? Speak to an iEnvi expert at info@ienvi.com.au or 1300 043 684, or contact us online.
Need advice on this issue? iEnvi provides practical, senior-led environmental consulting across contaminated land, remediation, ecology and environmental risk.
Team credentials Contaminated land advice Remediation services Groundwater services Talk to iEnvi