In recognition of the significant development pressures in the Wianamatta South Creek catchment, this Cumulative Impact Assessment was commissioned to inform Infrastructure NSW, NSW Department of Planning and Environment – Environment and Heritage Group and Councils within the Catchment (Camden, Blacktown Liverpool and Penrith) of the flood constraints that could impact on development within the South Creek catchment. The assessment uses the adopted hydrologic and hydraulic models for the catchment from ‘Wianamatta South Creek Catchment Flood Study – Existing Conditions’ (Revision I, Advisian 2022) to define contemporary flood characteristics and to test a range of development and floodplain modification scenarios.

The assessment:

• highlights the critical importance of maintaining areas of flow conveyance and flood storage.

• developed mapping of the areas critical to the conveyance of floods that should not be disturbed or too heavily vegetated

• provides a list of recommendations that are considered essential for mitigating the cumulative impacts of potential future development in the Wianamatta South Creek Catchment