ICMM Guidance > A Practical Guide to Catchment-Based Water Management > Catchment-Based Water Management

Catchment-Based Water Management

A catchment (p15) is the area of land from which all surface run-off and subsurface waters flow through streams, rivers, groundwater aquifers and lakes into the sea, river mouth, estuary or delta; and the water downstream affected by the site’s discharge.
The term catchment is sometimes used interchangeably with drainage basin or watershed.

A catchment-based approach looks at activities and issues in the catchment as a whole, rather than viewing them separately.
This approach encourages companies to consider holistically how competing demands on water resources from a range of stakeholders can create pressures and lead to conflict if not appropriately managed.

This method draws attention to the complex nature of water risks and identifies response options in instances where risks arise, or require action outside the operational boundaries of the mine.

A catchment-based approach requires people from different sectors to be brought together and identify issues, agree priorities and build local partnerships.

Water management and mining

Mining and metals operations can impact catchment dynamics through:

  • Their physical footprint
  • Extraction
  • Processing
  • Operational discharge processes

Companies can be impacted from:

  • Physical and socioeconomic dynamics in the area
  • Water availability
  • Water quality
  • Water withdrawal rates
  • Social pressures
  • Developmental priorities
  • National, regional or local policy changes

Why water is different

  • Not understanding stakeholder perspectives may lead companies to pursue behaviours and actions that could undermine trust, destroy relationships and increase the cost of business
  • Water availability is variable. Understanding operational and strategic risk around water is different from other natural resources. For example one river catchment may be suffering from a drought, but a neighbouring one is experiencing extreme flooding. Or, a catchment may face droughts and floods in quick succession
  • Water is a finite but renewable source – availability is physically constrained by infrastructure and legally constrained by historical water rights systems
  • Water cannot be substituted – whilst alternatives can be found for carbon, only water can be used for drinking or irrigation
  • Water is bulky and costly to move in large volumes, it is therefore a regional product and limited in the distance it can be transferred between catchments
  • Because of costs and the fundamental flow of water from upstream to downstream – users, risks and responses must be understood at a catchment level

Water management to water stewardship

Operations, corporate head office and senior management need to understand the value of water and their social licence to operate in order to prioritise resources and mitigations of risk. Company governance and resourcing structures require an integration of holistic understanding, communication and material water risks and a shift from traditional management methods.

The true value of water

The costs of operational controls and mitigation programs are hard to quantify. However the integration of water valuation across operating processes should enable solutions that protect, and create significant business value.

Failing to reflect the cost of managing water from a technical perspective can lead to:

  • Water surplus
  • Water deficit
  • Failure to dewater ahead of a mine plan or lack of environmental compliance which can lead to operational risk
  • Mine closure plans which underestimate the costs of rehabilitation and long term liabilities of treating mine-impacted water for many years after the point of closure

Poor social management of water can lead to:

  • The erosion of stakeholder relationships
  • The loss of the company’s social licence to operate
  • Costly delays
  • Regulatory pressure
  • Lack of access to permits
  • Challenges to future mine expansions

Water valuation benefits companies by:

  • Identifying comprehensive and accurate planning and cash-flow forecasts
  • Providing a decision support tool
  • Providing motivation to manage water resources
  • Protecting the value of the operation
  • Enhancing collaboration, behaviours and actions to build trust
  • Enhancing licence to operate through transparency

Water as a business risk

Companies need to consider water use in the context of its local availability and demand. A number of direct, indirect and catchment risks need to be taken into account. Each of these risk categories (p18) may result in reduced operational performance, increased costs, short-term shutdowns and even mine closure; causing a potential severe and negative impact on the net present value of the mine and impact shareholder value.

Further Reading: