100 Year Floodplains
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Interest Report 100 Year Floodplains Interest Type 100 Year ARI Floodplain Product Custodian Department of Water Local Government City Of Swan Authority Area Of Interest Land Parcel - Address: L 8254 FORD ST WOODBRIDGE 6056; Parcel Id: Lot 8254 On Plan 173536 3153'17"S 11559'10"E 3153'23"S 11559'15"E Note: Image supplied is for reference only. It is scale dependant and therefore may not show the Interest in relation to properties displayed herein. Always review the content of this report to determine the outcome for your property. Request 35393728 Tue Oct 12, 2010 14:00:18 WST Page 1 of 5 Interest Report 100 Year Floodplains About This Interest Report This report will provide 100 year Average Recurrence Interval (ARI) floodplain mapping for your area of interest. What is a 100 Year ARI flood? The 100 year ARI flood has been generally adopted in Australia and overseas as the basis for floodplain management planning. The 100 year ARI flood has a 1% chance of occurring in any one year and a 50% chance of being experienced at least once in a person's life time. Larger floods will occur but, on average, will be less frequent. Floodplain Mapping and Floodplain Development Strategies The Department of Water in carrying out its role in floodplain management provides advice and recommends guidelines for development on floodplains with the object of minimising flood risk and damage. The following guiding principles ensure proposed development in flood prone areas is acceptable with regard to major flooding: - Proposed development has adequate flood protection from a 100 year ARI flood; and - Proposed development does not detrimentally impact on the existing 100 year ARI flooding regime of the general area. 100 year ARI floodplain mapping for the watercourses in the Perth Metropolitan area includes the Swan River and its major tributaries between Fremantle and the Hills. The tributaries include the Ellen Brook, Helena River, Bennett Brook, Blackadder Creek, Jane Brook, St Leonards Creek, Susannah Brook, Henley Brook, Ellen Brook, Canning River and Southern River / Wungong Brook. Outside of the Perth Metropolitan area, the Department of Water has floodplain mapping for a number of major rivers through population centres, including : - Blackwood River (Bridgetown, Boyup Brook, Nannup, Augusta) - Preston River (Donnybrook, Bunbury) - Collie River (Collie, Australind/Eaton) - Murray River (Pinjarra to Peel Estuary) - Serpentine River (South West Highway to Peel Estuary) - Hotham River (Boddington) - Avon River (Toodyay to Beverley, including the towns of Northam and York) - Moore River (Moora) - Greenough River (Walkaway to Indian Ocean) - Chapman River (Geraldton) - Gascoyne River (Carnarvon) - Fitzroy River (Fitzroy Crossing) Request Number: 35393728 Tue Oct 12, 2010 14:00:18 WST Page 2 of 5 Interest Report 100 Year Floodplains Generally, the mapping has delineated the 100 year ARI floodplain into floodway and flood fringe areas. These terms can be defined as : Floodplain The portion of a river valley next to the river channel which is covered with water when the river overflows its banks during major river flows. The term also applies to land adjacent to estuaries which is subject to inundation during flooding. Floodway The river channel and a portion of the floodplain which forms the main flow path for floodwaters once the main channel has overflowed. If the floodway is even partially blocked then upstream flood levels may be raised and thereby affect areas which may not have been previously affected. Proposed development in floodways that is considered obstructiveto major flows is not acceptable. Flood Fringe The area of the floodplain, outside of the floodway, which is affected by flooding but where proposed development could be permitted, subject to building conditions. These areas are generally covered by still or very slow moving waters during a 100 year ARI flood. A minimum habitable floor level of 0.50 metre above the adjacent 100 year ARI flood level is generally recommended. Legislation governing the Interest 100 Year ARI Floodplain Water Resources Legislation Amendment Act 2007 Water Agency (Powers) Act 1984 Agency Response Based on the 100 Year ARI floodplain mapping your property has been identified as being within the 100 year ARI floodplain, or within 300 metres of the floodplain, and may be affected by flooding during a 100 year Average Recurrence Interval (ARI) event. The Floodplain Development strategy for the area states: - Proposed development (ie filling, building, etc) that is located outside the floodway is considered acceptable with respect to major flooding, however, a minimum habitable floor level of 0.50 metre above the adjacent 100 year ARI flood level is generally recommended. - Proposed development (ie filling, building etc) that is located within the floodway and is considered obstructive to major flows is not acceptable as it would increase flood levels upstream. No new dwellings are acceptable within the floodway. The increase in flood level that will result from total development of flood fringe areas has been calculated to be no greater than 0.15 metre. Please note that this strategy also applies to land outside of the 100 year ARI floodplain to ensure that adequate flood protection is provided against the 100 year ARI flood event. Further site specific information should be sought from the Department of Water (refer to contact details below). This advice is related to major river flooding only and other planning issues, such as environmental and Request Number: 35393728 Tue Oct 12, 2010 14:00:18 WST Page 3 of 5 Interest Report 100 Year Floodplains ecological considerations, may also need to be addressed. Details of the area are as follows: sdasda - draft name Upstream of the Causeway and Canning Bridge strategy T:\WR Management\Water Resource Assessment\Floodplain Management\FPM\FPM strategy diagrams\swan_canning\sw_strat_up.jpg The Department of Water should be contacted for further site-specific information: HEAD OFFICE The Atrium 168 St Georges Terrace, Perth, Western Australia PO Box K822 Perth Western Australia 6842 Phone: (08) 6364 7600 Fax: (08) 6364 7601 Email: [email protected] Internet: www.water.wa.gov.au Request Number: 35393728 Tue Oct 12, 2010 14:00:19 WST Page 4 of 5 Acknowledgement Interest Enquiry delivers information compiled from a range of government agency sources using SLIP Enabler - A revolutionary way to use and share Government spatial information in Western Australia. Only information approved by the relevant data Custodian is included in an Interest Report. If your enquiry is about the system, please call Landgate's customer service team on (08) 9273 7333. If your enquiry is about an Interest, please refer to the Custodian's contact details included in this Interest Report. For details about SLIP Enabler go to www.walis.wa.gov.au/SLIP or email [email protected] Disclaimer The information contained in this document ("Information") may be derived from several sources. While this Information is provided in good faith, this does not mean that it is accurate, complete or suitable for your purpose. Information from third parties is provided for convenience only, without any endorsement by Landgate. If you use the Information you must verify it with your own professional advisers or the relevant Government agency sources. Landgate disclaims liability for any use of or reliance on the Information, to the extent permitted by law..