Council is currently seeking feedback on proposed interim Flood Planning Levels for the Clarence River floodplain, which is based on Council’s recently adopted Lower Clarence Flood Model Update 2022.
At the October 2023 Council meeting, it was resolved to exhibit a draft planning control for interim Flood Planning Levels.
The proposed Flood Planning Levels are the 1% Annual Exceedance Probability (1 in 100 year) flood event that includes climate change considerations. An additional 500mm ‘freeboard’ is added to this flood event to determine the proposed interim Flood Planning Levels.
It is proposed new homes or residential development with habitable rooms will be required to be built above this Flood Planning Level.
The Lower Clarence Flood Model Update 2022, including interim Flood Planning Levels proposed, animations and other details are available here: https://www.clarence.nsw.gov.au/Council/Our-performance/Plans-and-strategies/Floodplain-Management-plans-studies-and-animations
To see the proposed flood planning levels, please go to Council’s Online Mapping System:
- Go to: https://maps.clarence.nsw.gov.au/intramaps910/
- Once you are on IntraMaps, tick "Agree" and select "Start IntrapMaps"
- Under “Modules” on the left side of the page select “Flood and Topo”
- Under "Layers", expand the "Flood Information" tab by selecting "+" to the left of the box.
- Once you are in the Flood Information, scroll down and select “Climate Change (CC1) 1in100”
- Select "Address Search" from the yellow menu bar beneath the map
- Enter the address you are interested in
- The interim Flood Planning Level is the "Climate Change (CC1) 1in100" level shown for the property, plus 500mm freeboard.
If you need any assistance please contact Council on 02 6643 0200.
The proposed interim flood planning levels, and any submissions during this exhibition period, will be considered by Council before being adopted.
Submissions close 4pm Monday 29 January 2024.
Council has recently adopted the Lower Clarence Flood Model Update 2022. This has been through a peer review process and endorsed for adoption by the Department of Planning and Environment (DPE), Council’s Flood Risk Management Committee and adopted by Council.
The current state of play is:
- Council has a number of older Flood Plain Risk Management Plans which remain current as an established policy basis under the Floodplain Development Manual 2005;
- The 2013 Lower Clarence Flood Model includes established policy about including climate change assumptions in the current Flood Planning Levels;
- The updated 2022 Flood Study indicates increased levels of risk from flooding, especially if reasonable climate change assumptions are made in accordance with adopting the 1% AEP Climate Change 1 (RCP 4.5) as the Defined Flood Event; and
- The 27 June 2023 Council resolution (06.23.009) requires Council to commence a new Floodplain Risk Management Study and Plan for the Clarence River floodplain, noting this process is estimated to take at least 18 months to complete.
Given the above, it is necessary to adopt an interim Flood Planning Level as soon as possible now that the 2022 Flood Model is endorsed, and some heightened flood risks are known. This approach is recommended to manage Council’s duty of care to the community, its responsibilities under the Local Government Act 1993, the need to consider the precautionary principle in floodplain management, and requirements to properly consider flood risk (inclusive of climate change) when assessing development applications under the Environmental Planning and Assessment Act 1979.
Including climate change in Flood Planning Levels is “Best Practice” and must be considered in strategic planning and development assessment. The RCP4.5 climate change scenario chosen is the mid-range scenario that aligns with Council’s Disaster Resilience Framework. RCP4.5 is a middle-of-the-road greenhouse gas emission scenario where some mitigation of GHG emissions occurs.
Council will consider all submissions before deciding how to proceed in early 2024.
If Council resolves to proceed, the next steps would be to commence the process of modifying Floodplain Management Controls in Council’s Development Control Plans to align with the interim Flood Planning Levels. This may include:
- Controls that require all new residential development to have a primary habitable floor level above the 1% AEP Climate Change 1 (RCP 4.5) scenario as the Defined Flood Event + 500mm Freeboard;
- Removal of clauses that permit Primary Habitable Floor Levels in North Grafton below the interim Flood Planning Levels;
- Include Objectives and Controls that permit habitable floor levels below the Flood Planning Level in limited circumstances, such as being limited to alterations and additions to existing dwellings;
- Update controls that any development below the Flood Planning Level must be constructed from Flood Compatible Building Components;
- Consideration of any feedback received during exhibition of the interim Flood Planning Levels;
- Any other necessary amendments to effect these changes; and
- Reporting the draft amendments to Council for endorsement before exhibition.
Make a submission