SWIS Peaker Project

Alinta Energy Development Pty Ltd (Alinta) was investigating the option to develop approximately 400 megawatts (MW) of fast-start, open-cycle gas turbines to be connected to the South West Interconnected System (SWIS), known as the SWIS Peaker Project. The proposed location is on cleared agricultural land approximately 200 kilometres north of Perth, near the town of Cataby.

The stormwater analysis confirmed that overland runoff within the site can be managed through internal drainage systems. The risk of downstream scour and sedimentation was minimal, as flow velocities were projected to remain below critical thresholds. However, if significant alterations occur to runoff coefficients, landcover or the terrain of the Iluka mine site post-closure, diverging substantially from the pre-existing conditions, the Project may require re-evaluation. Nonetheless, it is anticipated that stormwater flows will remain below critical velocities for the 1% AEP.

The study revealed no significant or irreversible impact on inland water environmental values, indicating that the project aligns with the Environmental Protection Authority objectives to maintain surface water quality.