Gibbergunyah Creek catchment is located in Wingecarribee Shire Southern Highlands of NSW 130 km south west of Sydney. The catchment is part of the Nattai River catchment which drains to Lake Burragorang as part of the Hawkesbury/Nepean catchment. Gibbergunyah Creek drains in a northerly direction through the Mittagong urban area where it is joined by tributaries Chinamans Creek and Iron Mines Creek. It continues to flow beneath the Hume Highway until its confluence with the Nattai River.
Phase I – Draft Floodplain Risk Management Study in which the floodplain management issues confronting the study area are assessed, management options investigated, and recommendations made. The objectives of this phase for Gibbergunyah catchment include:
- Review of Council’s existing environmental planning policies and instruments including Council’s long term planning strategies for the Study Area;
- Calculate flood damage estimates for existing conditions;
- Identification of works, measures and restrictions aimed to reduce the social, environmental and economic impacts of flooding and the losses caused by flooding on development and the community, both existing and future, over the full range of potential flood events;
- To assess the effectiveness of the works and measures for reducing the effect of flooding on the community and development, both existing and future;
- To consider whether the proposed works and measures might produce adverse effects (environmental, social, economic, or flooding) in the floodplain and whether they can be minimised;
- Examination of the present flood warning system, community flood awareness and emergency response measures in the context of the NSW State Emergency Service's developments and disaster planning requirements.
- Examine ways in which the river and floodplain environment may be enhanced by preparing a strategy for vegetation planning that will create a valuable corridor of vegetation without having a detrimental effect on flooding; and
- Identification of modifications to current policies required in the light of investigations.
Phase II – Draft Floodplain Risk Management Plan which is developed from the Floodplain Risk Management Study and details how flood prone land within the study areas is to be managed moving forward. The primary aim of the Plan is to reduce the flood hazard and risk to people and property in the existing community and to ensure future development is controlled in a manner consistent with flood hazard now and in the future. The Plan consists of prioritised and costed measures for implementation.
