Proposed Interim Flood Planning Levels

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At the June 2024 Council meeting, it was resolved to adopt the Interim Flood Planning Levels for the Clarence River.

The Interim Flood Planning Levels are informed by the peak flood depths across the Clarence Valley floodplain during a predicted 1% annual exceedance probability (AEP) flood event that includes mid-range climate change considerations, as indicated by the Lower Clarence Flood Model Update 2022 (see image below). An additional 500mm ‘freeboard’ is added to this flood event to determine the proposed interim Flood Planning Levels.

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New homes or development with habitable rooms will be required to be built above this Flood Planning Level.

"Generally, the proposed Flood Planning Levels increase in all cases, more in Grafton and surrounds, and lesser in the Lower Clarence," Clarence Valley Council Manager Development and Land Use Planning Murray Lane said.

"This is because the proposed Flood Planning Levels include greater climate change assumptions than the current 2013 Flood Model. The 2022 Flood Model includes up-to-date assumptions about sea level rise and increases in rainfall and runoff associated with climate change.

"Including climate change in Flood Planning Levels is best practice and must be considered, as required by the NSW Government’s current flood planning policy and guidelines.

"The proposed interim Flood Planning Levels do not affect the use of existing homes or buildings, and will only apply to new development where habitable rooms are proposed."

 

Why an 'interim' Flood Planning Level?

Council has a responsibility to quickly incorporate the most up-to-date flood planning information from the 2022 Flood Model into Council's planning controls. Due to recent changes by the NSW Department of Planning and Environment to the standardised Local Environmental Plan which affects how Flood Planning Levels are determined, Council has commenced preparation of a new Floodplain Risk Management Study and Plan which is expected to take 18-24 months. The interim Flood Planning Levels will be in effect until a new Floodplain Risk Management Plan is adopted.

The FPL for north Grafton is to be in accordance with the Lower Clarence Flood Model Update 2022 – 1% AEP with the mid range Climate Change Scenario plus freeboard of 500mm. However, in June 2024 Council resolved that the draft DCPs allow for the consideration of floor levels in Grafton for infill development to be reduced to no lower than the revised 1% AEP plus 500mm freeboard, that is, without the inclusion of the Climate Change scenario levels. This has been included as an option for applicants as there is currently an option to vary the FPL in Grafton with justification.

This will only be considered where an applicant can demonstrate that the new FPL for the development is not feasible or practical due to the resident’s accessibility requirements, the unreasonable impacts on neighbouring properties resulting from earthworks/filling, the building construction cost no longer being feasible, or the unreasonable impacts on heritage values. The controls will still require all building components below the interim FPL to be flood compatible regardless of the floor level approved.

You can view how the Flood Planning Area mapping and Flood Planning Levels affect your property on Council’s online mapping system. Select the “Planning & Development” Module, then the “Proposed DCP Flood planning area” Layers. You will be able to see the flood depths by clicking on the + icon. Type your address into the “Address Search” tab at the bottom of the page and once you click the “Search” button, the map will zoom in to the selected property. Please note that it might take a while to load. If you would like assistance, please call 02 6643 0200 and ask to speak with a Duty Planner.

The Lower Clarence Flood Model Update 2022, flood animations and other flood plain risk management information are available here:https://www.clarence.nsw.gov.au/Council/Our-performance/Plans-and-strategies/Floodplain-Management-plans-studies-and-animations

 

Proposed Development Control Plan Amendments

At the July 2024 Council meeting, Council endorsed proposed amendments to the Development Control Plans (DCPs) to be placed on public exhibition from 9 August to 9 September. The changes include updates to reflect the Interim Flood Planning Levels, updating terms to be consistent with the NSW Government’s Flood Risk Management Manual. There are specific considerations for north Grafton floor level controls and updates to the Wooli and Glenreagh controls. In addition, updated Flood Planning Area maps are proposed to be included in the updated DCPs.

If you would like to discuss these changes with Council officers in person, drop-in sessions will be held at:

  • Maclean Council Chambers – Wednesday 28 August at 11:30am to 1:30pm
  • Grafton Council Chambers – Thursday 29 August at 11:30am to 1:30pm
  • Yamba Wooli Street Hall – Tuesday 3 September at 11:30am to 1:30pm
  • Iluka Bowling Club – Thursday 5 September at 11:30am to 1:30pm
  • Glenreagh General Store - Wednesday 4 September at 9:30am to 11am
  • Wooli Hotel Motel - Wednesday 11 September at 12pm to 1:30pm

 

To have your say and for Frequently Asked Questions, go to Council’s On Exhibition webpage: https://www.clarence.nsw.gov.au/On-exhibition/Flood-Planning-Levels-Proposed-Development-Control-Plan-Amendments