National Flood Information Database
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Planning for stronger, more resilient floodplains Planning Institute of Australia (Queensland Division) 19 March 2012 Presentation Outline Project Context Commission of Inquiry Initial Observations from Final Report Part 1 Update Floodplain mapping progress Planning scheme implementation progress Part 2 Overview Flood investigation guidance Planning evaluation and land use strategies Planning scheme provisions Flood investigation case study – St George Consultation National Work Snapshot Discussion The journey so far... Commission of Inquiry Report Interim report – 1 August 2011 Final report – 16 March 2012 177 Recommendations across 17 chapters including the following of relevance:- Chapter 2 Floodplain management Chapter 3 Planning framework Chapter 4 State planning instruments Chapter 5 Local planning instruments Chapter 7 Development and flood considerations Chapter 8 Development assessment in practice Chapter 9 Building controls Chapter 10 Essential services Chapter 11 Buy-backs and land swaps CoI summary as it relates to Authority • The (Authority’s planning scheme) review conclusions lead the Commission to find that there is, in Queensland, a wholly inadequate level of flood mapping • Not all parts of Queensland need a comprehensive flood study - It is not feasible, nor is it necessary, for sophisticated flood mapping to be completed on a state-wide basis • It is not best practice to conduct a flood study for an urban area alone or even for a LGA - A flood study should be completed over a whole catchment • All levels of government would benefit from access to guidelines. Several relevant guidelines already exist including the Authority’s Part 1 and Part 2 guidelines. • QG should draft model flood planning controls, using a similar format and structure to that in the QPP. • Existence and maintenance of a repository of data • QG consider allowing councils to amend a planning scheme by way of the minor amendment process. • The Commission commends the consistent approach to floodplain management proposed by the Authority. • The Commission acknowledges the extensive work that has gone into the interim floodplain maps. Planning for stronger, more resilient floodplains Scope: • Two part Guideline – Part 1 – Interim measures – Part 2 – Long term solutions • Continue to promote the improvement of floodplain mapping around the state • Guide the preparation of new flood investigations, relative to Councils’ need and resourcing capabilities. • Provide a comprehensive suite of land use transition strategies and development controls for inclusion in new planning schemes An Integrated Approach across a range of disciplines - Project focuses on Land Use Planning QldRA Project Overview Planning for stronger, more resilient floodplains assists Councils to ensure that floodplain management is addressed through land use planning. • Part 1 – Interim measures to support floodplain management in existing planning schemes - an information toolkit including mapping identifying an interim floodplain assessment overlay and interim floodplain management controls. • Part 2 – Measures to support floodplain management in future planning schemes - consistent floodplain Improving floodplain management controls and regulation across Queensland within new planning schemes prepared under the management through Sustainable Planning Act 2009. the land use planning process... Policy Context • SPP 1/03 review • QRA work informs but does not replace SPP 1/03 review • Queensland Floods Commission of Inquiry • QRA work considers & complements CoI recommendations • SPP 3/11: Coastal Protection & SPP 4/11: Wetlands Protection • Supports policy outcomes in coastal & wetlands areas • Use of Guideline in planning scheme reviews (existing & future) • For voluntary adoption by Councils • May be used to inform State agency reviews of schemes PART 1 – Interim Solution TOOLKIT Draft Toolkit released on 17 September 2011 for consultation GUIDELINE Toolkit includes: Part 1 • Guideline • Interim Floodplain Assessment Overlay Mapping • Model Development Controls Final version released on 23 January 2012 following consultation period Mapping Controls EXAMPLE Mapping - Bushfire Mapping produced by QFRS across the State for each Local Government Area. State wide model of potential bushfire risk areas to be used for planning – default state- wide mechanism Based of three variables:- • Slope (fire burns quicker on greater slopes) • Aspect (Exposure of direct sunlight on vegetation) • Vegetation • Remnant Vegetation, Pre-clear Vegetation, Tropical Savannahs and Tree Survey data where available SUMMARY – Dawson River Sub-basin 10m Contours LandSat Gauging Heights Pre-cleared Stream Orders Aerial for towns vegetation 5 – 9 Alluvial Soils & Pre-Clear Vegetation Layer 2011 Flood Event – Satellite Imagery over Alluvial Soils & Pre-Clear Vegetation Layer Contours from the 1 second DEM (Best available elevation data) Interim Floodplain Overlay Assessment determined by DERM cartographers from all inputs Flood Mapping – Needs to be fit for purpose Not all parts of Qld need a comprehensive flood study. CoI Final Report, March 2012, pg 54 State-wide mapping • 129 Sub-basins across Queensland • 116 sub-basins have been mapped to date • In total 99.2% of the State has been assessed for floodplains • 26.6% identified within the IFAO • 8,847 map pages produced to date (A3 @1:50,000 scale) • Over 450,000km2 identified as part of Interim Floodplain Assessment Overlay from these 116 river sub-basins • Using more than 35 experienced cartographers • Largest mapping exercise across the country in a long time Working with DERM, the QldRA has • 116 sub-basins completed in under over a matter of months, created seven months maps covering most of Queensland. CoI Final Report, March 2012, pg 67 The 11 sub-basins currently not mapped are: • Hinchinbrook Island • Whitsunday Island • Curtis Island • Fraser Island • Maroochy River • Caboolture River • North Pine River • South Pine River • Stradbroke Islands • Moreton Island • Misc. Other Islands Two sub-basins underway: Mornington Island and Torres Strait Islands are currently being mapped. The 5 sub-basins which were partly mapped: • Brisbane River (excluded LGA's of Brisbane and Ipswich) • Bremer River (only mapped in Scenic Rim LGA) • Logan River (only mapped in Scenic Rim LGA) • Albert River (only mapped in Scenic Rim LGA) The interim floodplain maps are a • Coomera & Nerang Rivers (only mapped in Scenic level above not having any flood Rim LGA) mapping at all. CoI Final Report, March 2012, pg 66 Model development controls • Mapping is only one piece of the puzzle - need development controls to support mapping • Development on land in potential flood area is subject to development controls e.g. Regulating filling and elevation of floor levels • The right development controls and mapping will allow better built form outcomes with respect to flood • Acceptable Outcomes can be tailored to local circumstances Part 1 – Built Form Outcomes... Resilient Queenslander... Mitchell, January 2012 Building back better... Condamine, late 2011 Slab on ground construction... St George, January 2012 Part 1 – Case Study Central Highlands Emerald – experienced significant flooded in 2008 (previously highest) and even higher in Dec 2010 Council administers four planning scheme (pre- amalgamation) No flood mapping or provisions existed in planning schemes Some local information collated post events Council able to utilise the IFAO mapping and locally verify to prepare flood hazard overlay All four existing planning schemes amended through a streamlined amendment process – less than one month Part 1 – Implementation Progress • Actively working with other Councils to amend their schemes ie. Banana Shire, Balonne Shire, Somerset Regional, Burdekin Shire, Scenic Rim Regional • Others utilising floodplain mapping for future planning scheme - Part 2 work • All indigenous schemes to utilise the mapping The interim floodplain maps can be incorporated into a planning scheme process by way of the minor scheme amendment process. CoI Final Report, March 2012, pg 128 Where are we now? Part 2 – Understanding • Management of floodplains is adhoc and piecemeal – Need to promote whole of sub-basin approach through Regional Planning Committees • Conventional floodplain management practice promotes comprehensive approach to flood mapping and risk management – Costly, complex and may be more than required in lower growth/regional areas – Flexible, fit-for-purpose approach is more appropriate • Availability of appropriate data – Contours, DEM & Aerial Imagery through Hazard: The natural event LiDAR capture program Risk: Responding to the hazard • Flood Risk = Consequence x Likelihood – Current practice focuses on likelihood rather than consequence, e.g. 1% AEP • Planners give limited consideration to consequence – Need to change the way we plan in floodplains Understanding Consequence Key Messages in Part 2 • Promote fit-for-purpose approach to floodplain management • A Whole-of-sub basin approach – administered through Regional Planning Committees • Different levels of flood investigations are appropriate relative to a Council’s circumstances • Improve planners’ understanding of flood, particularly consequence, using a planning evaluation • Develop considered land use strategies for floodplains - do not sterilise all flood risk areas • Use QPP planning schemes to deliver planning outcomes (particularly the strategic framework) Part 2 – Long term solution Measures to support floodplain management