Georges Hall Catchment Flood Study

The Study Area

The Georges Hall study area is located in Bankstown, south west Sydney and is contained within the
suburb of Georges Hall. The Georges Hall catchment area is approximately 140 hectares of
predominantly residential land. Elevations range from over 50 mAHD in the east to approximately 2.5
mAHD along the banks of Prospect Creek and the Georges River. The catchment drains in a
westerly direction along three distinct drainage lines though much of the flow is overland with the first
noticeable channel appearing within the Amaroo Reserve towards the downstream extent of the
study area.

The Georges Hall catchment is bounded to the north by Flinders Road, south by Birdwood Road and
Beale Street, to the east by the Crest Reserve and to the west by the Georges River. The catchment
forms part of the wider Prospect Creek / Georges River catchment which discharges into Botany Bay.
The eastern boundary of the study area in Crest Reserve forms the catchment divide with the
Villawood Drain catchment, which itself is a tributary of Prospect Creek. More information relating to
the hydrological catchment is outlined in the Georges Hall Catchment Flood Modelling Report, in
Appendix B.

The Floodplain Management Process

The prime responsibility for planning and management of flood prone land in New South Wales rests
with local government. The NSW Government provides assistance on state-wide policy issues and
technical support. Financial assistance is also provided to undertake flood studies and floodplain
management studies, and for the implementation of works identified in these studies.
Flood Prone Land Policy and the Floodplain Development Manual (NSW Government, 2005) form
the basis of floodplain management in New South Wales.

The objectives of the Policy include:
<ul>
<li>Reducing the impact of flooding and flood liability on existing developed areas by flood mitigation
works and other measures; and</li>
<li>Reducing the potential for flood losses in new development areas by the application of
ecologically sensitive planning and development controls.</li>
</ul>

The Policy provides some legal protection for Councils and other public authorities and their staff
against claims for damages resulting from their issuing advice or granting approvals on floodplains,
providing they have acted substantially in accordance with the principles contained in the Floodplain
Development Manual.
The implementation of the Flood Prone Land Policy generally culminates in the preparation and
implementation of a Floodplain Management Plan. The Georges Hall Catchment Flood Study is one
of the first steps in preparing the Plan, and involves an assessment of existing flood conditions
throughout the catchment. The steps in the floodplain management process are summarised in
Figure 1-2.

Outcomes from the Study

The main outcomes from this study include:
<ul>
<li>A database of all public drainage assets within the study area;</li>
<li>Establishment of a computer model capable of assessing flood behaviour;</li>
<li>Information on flood behaviour under existing catchment conditions;</li>
<li>Information on potential constraints in the drainage assets for various storm events;</li>
<li>A property database including surveyed floor levels, flood levels and the resulting floor level
immunity, expressed in the magnitude of a storm event;</li>
<li>Predicted change in flood behaviour due to the potential impacts of climate change; and</li>
<li>A model that can be used to assess flood mitigation options and future development proposals.</li>
</ul>

Tags: Bankstown, Georges Hall
Organization: Canterbury-Bankstown Council