|Designer: Roger BrisbaneContractor:Morton Urban SolutionsClient:Stockland Development Pty LtdLocation:Ormeau, Gold Coast City, Queensland, AustraliaCompletion Date:2013|
Outline: Ridge is an 890 lot residential subdivision located adjacent to an existing flood plain and within the Gold Coast / Brisbane “Green Belt”. Compensatory earthworks for flood mitigation and requirements to place bio-retention basins above major storm levels presented technical challenges for piped stormwater conveyance systems.
Background: Mortons Urban Solutions was commissioned to undertake design, project management and construction supervision of the project to fulfil part of the regions demand for residential lots in the fastest growth corridor in Australia.
Methodology: Restrictive floodplain dynamics presented opportunities to utilise the full potential of 12d Dynamic Drainage Analysis (DDA), and permitted calculations, iterations and interrelations that would be unthinkable in any other drainage analysis package.
Issues: In order to fully utilise the site’s potential an end of line bio-filtration approach was adopted, however this presented additional problems with conveyance of large quantities of piped stormwater. 12d’s DDA facilitated a highly interrelated system incorporating bio-filtration basins, piped drainage, multiple bi-directional pits and overland flow components, with each component affecting the functioning of the other. A series of 16 bi-directional pits within the estate permitted low flows (Q3 month) to be directed towards bio-filtration basins, whilst larger flows were discharged directly into the floodplain, thus allowing pipe and