Highview Court
Key Highlights
CLIENT
Private DeveloperLOCATION
Onkaparinga HeightsTYPE OF WORK
Flood Modelling, Stormwater ManagementProject Summary
Sproutt was engaged to prepare a Stormwater Management Plan (SWMP) for a proposed development within the City of Onkaparinga. The plan was developed in accordance with the City of Onkaparinga Stormwater Management for Development – Technical Guidelines. To support flood risk assessment and inform site planning, Sproutt completed detailed 2D rain-on-mesh flood modelling using HEC-RAS. This modelling identified the 1% Annual Exceedance Probability (AEP) flood extent across the site, providing essential data for layout and infrastructure decisions.
Our Approach
Sproutt’s approach was driven by a need to understand and manage flood risk at both the site and catchment scale. Using HEC-RAS, the team conducted 2D rain-on-mesh simulations to capture overland flow dynamics and flood behaviour under design storm conditions. The modelling was calibrated to reflect local topography and drainage characteristics, ensuring accurate delineation of the 1% AEP flood zone. This data was used to guide development placement, access routes, and stormwater conveyance infrastructure.
The SWMP was prepared in alignment with the City of Onkaparinga’s technical standards, ensuring that the proposed development met Council expectations for flood resilience and stormwater performance.
Outcomes
The Stormwater Management Plan provided the developer with a clear understanding of flood-prone areas within the site, enabling informed decisions around building siting and infrastructure design. The 2D flood modelling outputs supported compliance with Council requirements and helped mitigate flood risk through strategic planning. The final plan ensured that the development could proceed with confidence in its ability to manage stormwater effectively and sustainably.
