Murray Flood Study
The coastal plain south of Perth in Western Australia around the Serpentine and Murray River floodplains is predominantly rural-zoned land that is under increasing urban development pressure. The area has relatively flat terrain, high groundwater tables, surface ponding in winter, wetlands of significance, an extensive rural drainage network and periodic riverine flooding.
Floodplain management is a key component of the urban planning process for the area.
The Murray Flood Study project was part of a larger project that developed a drainage and water management plan for an area around Pinjarra.
Government of Western Australia
This flood study updated the hydrologic characteristics of the area using additional gauging data and new techniques, including seasonal flood frequency analysis and storm surge modelling. This involved modelling the hydrology of the 8,000 km2 Murray River catchment using the RORB model. The area of floodplain mapping was expanded using two-dimensional models enabling better characterisation of flooding in smaller streams. The two dimensional DHI Mike Flood model was used for the floodplain modelling.
Interest from stakeholders in the overall drainage management for the area was high. A continuous consultation approach was adopted throughout the project. This involved presentation of modelling methods and results at a number of meetings and community forums during the life of the project.
A floodplain development strategy was produced that emphasises land use planning, development controls and emergency planning over structural measures and includes recommendations for the consideration of potential impacts of future climate change on flooding.