About the Basin / Sub Basin Flood Modelling and Mapping

The modelling of river basins and sub-basins is an innovative flood stu dy app roach that wa s com pleted dur ing Ph ase 3 of the Queensland Flood Mapping Program (QFMP). Reports, catchment scale models, flood maps and video animations are available.

Th e Basin Flood Mapping activity pro vides catchm ent s cale mod elling th at is fit -for-purpose, ri sk based and h ighly cos t effective solution th at ma ximises th e benefits of access to elevation d ata for t he en tire catchment ( SRTM d ata) a nd oth er ex isting d ata . A list o f these lo cations com pleted thr ough the Project has bee n o utlined i n the table below.

Th e s ub -basin leve l models prov ide gr eater un derstand ing of fl ood b ehaviour throughout var ious ca tchments du ring major fl ood e vents , in ma ny cases pro viding floo d map ping where no ne p reviously e xisted or had been loo sely es timated. Thi s mapping provide s detail a t a cat chment level a nd complements th e initi al statew id e ra pid flood h azard asses sment (QFAO) by providing an increased level of accuracy for identifying flood hazard at a catchment scale.

There are d efinite limitation s to th e a pplicability and accu racy of th e flood mod elling wh en und ertaken at a ca tchment sca le . The res ults are su itable fo r increasing th e comm unity und erstanding of fl ood ri sks, b ut should n ot be so lely r elied upon for des ign of fl ood miti gation o ptions such as levees or se tting building levels.

Th e models pro duced were developed using the SRTM d ata w ith a g rid reso lution of 90m ( or less w here ag reed) . T hi s is acc eptable for th e p urposes of flood mappi ng ac ross m ajor ri ver systems and areas currently without information . In addition, r esearch i nto th e dir ect ra infall approach , in p articular i dentifying ap propriate infiltr ation lo sses, is o ngoing.

As a co nsequence , th e methodology a dopted for the ca tchment mod els s hould b e co nsidered as c onservative . Importantl y, th e output s from the modellin g s hould not b e used for estimating fl ood levels. Th e verti cal acc uracy of th e SRTM DE M i s at be st ± 5m . Flood depth s s hould b e co nsidered a s indi cative onl y o n a br oad s cale .

Basin Name Sub-Basin Name Main Councils

Baffle Creek BAFFLE-KOLAN Gladstone, Bundaberg Kolan Creek Barron River BARRON Cairns, Tablelands, Mareeba Freshwater Creek Boyne River BOYNE-CALLIOPE Gladstone Calliope River Bowen River Lower Burdekin River Burdekin, Barcaldine, Whitsunday, Charters BURDEKIN Suttor River Towers, Isaac Upper Burdekin River Barker & Barambah Creeks Boyne & Auburn Rivers North Burnett, South Burnett, Bundaberg, Gympie, BURNETT Lower Burnett River Cherbourg, Western Downs Upper Burnett River Balonne River Condamine River Southern Downs, Toowoomba, Western Downs, CONDAMINE Maranoa River Balonne, Maranoa, Murweh, Paroo Wallam Creeks DON Don River Whitsunday Comet River Dawson River Fitzroy River Rockhampton, Central Highlands, Woorabinda, FITZROY Isaac River Banana, Isaac, Maranoa, Western Downs Mackenzie River Nogoa River HERBERT Herbert River Tablelands, Hinchinbrook, Cassowary Coast North Johnstone River JOHNSTONE Tablelands, Cassowary Coast South Johnstone River Lower Mary River Fraser Coast, Gympie, Sunshine Coast, Somerset, MARY Noosa River Noosa Upper Mary River Mulgrave River MULGRAVE-RUSSELL Cairns, Yarrabah, Tablelands Russell River MURRAY Murray River Cassowary Coast TULLY Tully River Tablelands, Cassowary Coast