Premise was engaged to prepare a Hydraulic Impact Assessment to investigate the pre-development, and mitigate post-development, flood scenarios for a range of design flood events and several construction stages. Hydrologic and hydraulic models (XP-SWMM) were developed, validated, and tested for the catchment encompassing the site.
These models were also utilised to develop mitigation strategies that would alleviate flooding in areas already subject to inundation. The modelling included a waterway crossing at Karrabin Rosewood Road and a partial upgrade to those culverts. The development was designed to convey flows with no worsening of flood conditions to surrounding properties.