Planning Report - 100988 · RAL25/0004

            ‘Detailed flood modelling of the catchment and subject intersection has
            demonstrated the capacity of the existing culverts provides 10% AEP design
            flood immunity to the intersection. For larger and rarer flood events of less
            than 2% AEP the model results show the intersection will experience water
            over the road to depths of less 0.3 m for a 1% AEP flood event for relatively
            short durations of less than 1.5 hours.

            The flood modelling has also demonstrated that should a significant blockage
            of the culverts occur during a major rainfall flood event the depths of inundation
            across the culvert would not be expected to significantly change, however, the
            inundation may persist for longer periods.’

            The proposed development will factor in these findings, noting the bio-retention
            basin and additional drainage infrastructure should aid in reducing inundation
            periods at the Lake Macdonald Drive – Dianella Court Intersection (see
            Appendix C, E & I for details).




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Planning Report No. 100988      Murray & Associates (QLD) Pty Ltd                  February 25