SOLOMON POWER STATION HYDROLOGICAL STUDY
Contract Power Group
Hydrological and 2D
Hydrological Study Report
The Solomon Power Station (SPS) is a gas-fired operation providing power to FMG’s Solomon Hub iron ore mining complex in the Pilbara region of Western Australia (WA).
The site includes the existing power station with a total area of about 30 ha, located about 300 km south-west of Port Hedland. The Indian ocean shoreline is approximately 200 km north of the SPS. The SPS site is located in the Hamersley Ranges, characterised by broad valleys and steep peaks with heavily eroded gorges. The site is surrounded on three sides by hills and has a broad flat valley to the east which slopes gently towards the Fortescue River.
Expanding the existing Solomon Power Station is currently being investigated and forms part of design deliverables to FMG.
The project’s overall objective was to determine the areas constrained by flooding and inform future planning and expansion of the SMS.
The project required an experienced team to undertake a Hydrological Study. 360 Environmental Pty Ltd (360 Environmental) was commissioned to provide a high-level hydrological assessment for the site. The focus was the potential flood issues at the site, assessing the flood extent and magnitude for several rainfall events and providing recommendations for future studies and planning.
360 Environmental’s Water Team undertook a hydrological, and 2- Dimensional (2D) hydrodynamic modelling to estimate the overland flows and surface flooding at the site. The hydrological model was used for calculating surface runoff. In contrast, the 2D hydrodynamic flood model was built for flood and hazard mapping. The models were simulated using 50%, 20%, 10%, 5% and 1% Average Exceedance Probability (AEP) rainfall events, and flood depth and hazard maps were produced. The modelling work was carried out considering the latest Australian Rainfall and Runoff: A Guide to Flood Estimation (Geoscience Australia, 2019).