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This consultation has concluded. Thank you for your feedback.
The Lismore Floodplain Risk Management Study has been prepared by Engeny Water Management and managed by Rous County Council under the guidance of Lismore City Council’s Floodplain Management Committee.
The study was initiated with assistance of grant funding from the NSW Government following the March 2017 flood in Lismore, when the CBD levee was overtopped for the first time since its completion in 2005.
The study set out to:
Develop calibrated hydrologic and hydraulic models based on best industry practice and up-to-date data.
Improve our understanding of flood behaviour to inform management of flood risk.
Identify and assess flood risk management measures.
Provide recommendations to inform development of an updated Lismore Floodplain Risk Management Plan (the next stage in the flood risk management process).
The study has now been finalised and Lismore City Council approved the study for public exhibition at its ordinary meeting on 10 November 2020.
The draft study report has identified:
That flood behaviour on the Lismore floodplain is very complex and difficult to model.
That the new hydraulic model for the Lismore floodplain represents recorded peak flood levels from historical events well, and was validated against previous models from 2018 and 1993.
That new flood levels for 'design' floods (floods that are estimated to happen) may be higher than Lismore City Council's currently adopted planning levels, requiring more evaluation before amendments are made to the Lismore LEP 2012 Flood Planning Level and Flood Planning Area.
That flood levels in Lismore tend to be dominated by flows down Leycester Creek.
That the magnitude of the 2017 flood event was estimated to be a 5% Annual Exceedance Probability (AEP) (1 in 20 year ARI event) when measured below the confluence of the Wilsons River and Leycester Creek and a 1% AEP (1 in 100 year ARI event) when measured at Tuncester.
Updated flood hazard categories (H1 to H6) for the Lismore area.
Six flood modification mitigation options for further investigation.
11 recommendations for further investigation and action.
The draft Lismore Floodplain Risk Management Study report is provided in the Document Library to your right in two parts - the appendices to the study includes 'design' event flood maps, flood impact maps of proposed measures and flood damage assessments. Also provided is a brochure that provides an overview of the key findings and recommendations of the study.
It is important that you read through the summary brochure and draft study document and/or have it accessible whilst completing the feedback form as it provides essential information and insights that will help inform your decision-making.
We are accepting feedback from the community until the 13 January 2021. After this time a report will be presented to Council in February 2021 detailing the community's feedback.
The Lismore Floodplain Risk Management Study has been prepared by Engeny Water Management and managed by Rous County Council under the guidance of Lismore City Council’s Floodplain Management Committee.
The study was initiated with assistance of grant funding from the NSW Government following the March 2017 flood in Lismore, when the CBD levee was overtopped for the first time since its completion in 2005.
The study set out to:
Develop calibrated hydrologic and hydraulic models based on best industry practice and up-to-date data.
Improve our understanding of flood behaviour to inform management of flood risk.
Identify and assess flood risk management measures.
Provide recommendations to inform development of an updated Lismore Floodplain Risk Management Plan (the next stage in the flood risk management process).
The study has now been finalised and Lismore City Council approved the study for public exhibition at its ordinary meeting on 10 November 2020.
The draft study report has identified:
That flood behaviour on the Lismore floodplain is very complex and difficult to model.
That the new hydraulic model for the Lismore floodplain represents recorded peak flood levels from historical events well, and was validated against previous models from 2018 and 1993.
That new flood levels for 'design' floods (floods that are estimated to happen) may be higher than Lismore City Council's currently adopted planning levels, requiring more evaluation before amendments are made to the Lismore LEP 2012 Flood Planning Level and Flood Planning Area.
That flood levels in Lismore tend to be dominated by flows down Leycester Creek.
That the magnitude of the 2017 flood event was estimated to be a 5% Annual Exceedance Probability (AEP) (1 in 20 year ARI event) when measured below the confluence of the Wilsons River and Leycester Creek and a 1% AEP (1 in 100 year ARI event) when measured at Tuncester.
Updated flood hazard categories (H1 to H6) for the Lismore area.
Six flood modification mitigation options for further investigation.
11 recommendations for further investigation and action.
The draft Lismore Floodplain Risk Management Study report is provided in the Document Library to your right in two parts - the appendices to the study includes 'design' event flood maps, flood impact maps of proposed measures and flood damage assessments. Also provided is a brochure that provides an overview of the key findings and recommendations of the study.
It is important that you read through the summary brochure and draft study document and/or have it accessible whilst completing the feedback form as it provides essential information and insights that will help inform your decision-making.
We are accepting feedback from the community until the 13 January 2021. After this time a report will be presented to Council in February 2021 detailing the community's feedback.
