RPS delivers CSG water paper for National Water Commission

RPS was engaged by the federal government to prepare a discussion paper for the National Water Commission’s Waterline program addressing a range of issues relating to coal seam gas (CSG) water.

The aim of the paper was to provide a foundation for discussion and to seed debate in relation to policy and management issues associated to Coal Seam Gas (CSG) water across Australia, predominantly in Queensland and New South Wales. The paper is a discussion starter for planners and water managers that has a focus on collating technical concepts, analysing jurisdictional arrangements, reviewing potential water uses, and identifying the future extent of the CSG water issue.

The RPS team undertook a national analysis and benchmarked their findings against similar international scenarios.

The discussion paper has now been used by NWC to develop a position statement on CSG water management and associated jurisdictional arrangements.

The key findings of the discussion paper were:

• There is a significant opportunity to substitute current water sources (e.g. groundwater extractions for irrigation, surface water flows for environmental purposes) with treated CSG water;
• Legislation and policy settings need to change to maximise beneficial reuse of CSG water;
• The environmental impacts associated with CSG water can be managed, but further assessment is needed; and
• Potential beneficial CSG water uses are numerous, but only a few are realistic.

The discussion paper compiled a number of interesting facts in relation to CSG water, including:

• The estimated CSG water volume over the next 25-30 years is an average of 157-313 GL/a, which is comparatively small compared to the 11,500 GL/a extracted annually in the Murray-Darling Basin. The CSG water, however, is significant on a regional basis;
• Approximately 70% of this water will come from the Surat Basin and 30% from the Bowen Basin;
• The CSG water: energy ratio (i.e. ML water / PJ energy) varies significantly within and between basins; and
• Raw CSG water can be described as having poor to very poor water quality, particularly in an environmental context. The levels of salts in CSG water are high and, in most locations considered by this discussion paper, the dominant salt is sodium.

The discussion paper can be read by clicking here.