Mining is a significant community issue and an important focus for WaterNSW. There is a long history of coal mining in the declared Sydney catchment. In recent years, coal seam gas has been an emerging issue in various parts of NSW, including the declared Sydney catchment.

The principal concerns for WaterNSW are that coal mining activities have the potential to affect

  • the quantity and quality of surface and groundwater in the Sydney catchment
  • water supply infrastructure
  • the ecological health of the Special Areas.

Surface water losses which may occur due to mining: As identified in our Literature Review report (link below), there are essentially three mechanisms which may potentially result in long-term or permanent removal of water from the surface water catchments across the Special Areas. These three mechanisms are summarised as follows and explained diagrammatically as indicative pre-mining and post-mining conditions.


Tuesday 18 January
2,497,329 ML
2,581,850 ML
9,342 ML
1,335 ML
-3,171 ML
Tuesday 18 January