Webuild

Luke Opray is a senior engineering manager with extensive experience in water infrastructure design and delivery across Australia’s resources and infrastructure sectors. He has worked on major desalination, wastewater and industrial water projects, including adaptive delivery models for complex mining environments.

In today’s mining landscape, uncertainty is the only certainty. Whether driven by volatile commodity markets, regulatory complexity or unpredictable geological outcomes, mining operations are increasingly seeking infrastructure solutions that are agile, cost-efficient and environmentally responsible. Nowhere is this more critical than in water infrastructure.

Water is both a vital input and a sensitive output for mining activities. From dust suppression and ore processing to environmental discharge and groundwater protection, water plays a role in nearly every operational activity and social license consideration. Yet, traditional approaches to designing water treatment and supply systems often fall short by assuming fixed production profiles and long-term output certainty. In reality, water demand can vary significantly throughout a mine’s life.

This article explores why scalable, staged infrastructure design is no longer just a best practice but a necessity for the mining sector. By embedding flexibility into water infrastructure, mines can ramp capacity up or down in line with production cycles, improve ESG performance and control operational costs.

Why Water Demands in Mining Are Unpredictable

Mining operations often commence with assumptions about ore grade, groundwater inflows and production volumes that shift significantly once operations begin. These shifts affect water balance models and, in turn, the scale and function of water management infrastructure.

Water demand variability can stem from:

• Start-up and commissioning delays

• Commodity price-driven production slowdowns

• Unexpected water characteristics

• Changing environmental discharge limits

• Expansion or contraction of mining footprint

Designing fixed-capacity water infrastructure under these conditions is like building a dam based on a 10-year rainfall average, misaligned with reality and vulnerable to inefficiency.

The Case for Staged and Modular Design

Staged infrastructure design introduces modularity and scalability into the initial design scope. Rather than committing to a single, high-capacity treatment plant, designers plan for a base capacity with integrated expansion pathways. Depending on the water management requirements, this modularity can take the form of “trains” (e.g., 20 ML/d units) or smaller skidmounted systems that can be independently operated, maintained or upgraded.

Benefits include:

• Operational flexibility: Infrastructure can match real-time demand rather than theoretical projections.

• Lower OPEX: Energy, chemical use and maintenance are scaled to actual operation, not unused capacity.

• Improved ESG outcomes: Less waste, reduced carbon footprint and better resource stewardship.

• Financial agility: CAPEX can be phased in line with production and cash flow.

Case Study: Surat Basin CSG Water Treatment Plants

In the Surat Basin of Queensland, two major Coal Seam Gas water treatment facilities were constructed, each designed for a total capacity of 100 ML/day. Crucially, both plants were made up of 5 x 20 ML/day treatment trains. This staged configuration was a deliberate response to uncertainty in produced water volumes.

“In a world where mining must operate at the intersection of profitability, sustainability and uncertainty, scalable water infrastructure is not a luxury; it’s a necessity.”

As gas production ramped up, the actual water volumes never reached the anticipated peaks. Thanks to the modular design, the plants could operate only the number of trains required at any given time, offering superior operational flexibility and cost efficiency.

With long-term operational contracts in place, skilled operators adjusted the plant's functionality to yield benefits such as:

• Reduced chemical and energy consumption

• Increased membrane longevity

• Simpler operations management

From an ESG perspective, these efficiencies contributed to a smaller environmental footprint and better alignment with stakeholder expectations.

A Blueprint for Future Mining Projects

Mining companies and designers should embed staging principles into water infrastructure planning from day one. This includes:

• Feasibility-level assessments of demand uncertainty

• Scenario-based infrastructure planning

• Modular procurement strategies

• Integrated lifecycle cost analysis

In addition, collaborative delivery models such as early contractor involvement (ECI) or alliance contracting can facilitate this flexibility, aligning design intent with long-term operational performance.

Conclusion

In a world where mining must operate at the intersection of profitability, sustainability and uncertainty, scalable water infrastructure is not a luxury; it’s a necessity. By adopting staged, modular water treatment systems, mining operators can adapt to changing conditions, minimize waste and uphold ESG commitments, all while preserving operational and financial resilience.

The Surat Basin CSG case is an example of how thoughtful infrastructure staging can deliver real-world value, even in the face of demand variability. As the industry moves toward more adaptive and sustainable models, designing for uncertainty will define the next generation of water solutions in mining.