RFI - Attachment E - SWMP Callaghan and Toth

                                                                              Callaghan & Toth


5.0 FLOODING ASSESSMENT SUMMARY
The flood study for the site was undertaken by Hydrology & Water Management Consulting.
The results of the updated flood study were not available when this SWMP was updated. The
brief summary below is based on the flood study dated 16 October 2019 (Ref. No.:
J00318R1V1).

5.1      Existing Conditions

The site is bounded to the south and east by Cooroy Creek.

The site is subject to ponding of floodwaters from the adjacent watercourses and the Q100 year
ARI flood levels (i.e. 1% AEP event) (see Appendix A in Flood Study). The Lower Mill site is
affected by flood levels across a range of events. The proposed carparks and access roads
and pathways are below the Q100 year inundation line.

The flood assessment from Hydrology and Water reports on the hydrologic and hydraulic
performance of the site including upstream and downstream catchments.

5.2      Proposed Drainage System

See the updated flood study detailing findings relating to the proposed works and structures and
effects on flooding in the area.




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2001 Lower Mill Carpark Extension SWMP                                         July 2020