Building a comprehensive spatio-temporal database of floodplain inundation for environmental management in the Murray-darling basin, Australia

Abstract

This paper describes an innovative large-scale floodplain modelling approach that was developed by integrating a suite of models (landscape model, hydrodynamic model and water balance model) and GIS for producing inundation maps at very high temporal and spatial resolutions under different antecedent conditions. A two-dimensional hydrodynamic model was initially calibrated and validated for historical events using observed water levels and flood maps derived from Landsat imagery. The results demonstrate highly satisfactory performance of the model in simulating floods of different magnitudes in a number of floodplains. The hydrodynamic model outputs were then processed using a simplified hydraulic and hydrological water balance model to simulate a range of flood events to produce a comprehensive and very high spatial resolution floodplain inundation database under different flow ranges and antecedent conditions. The model outputs are used by the Murray Darling Basin Authority (MDBA), Australia for decision making process for environmental management. The paper presents the overview of the methodology, the results of calibration and validation of the model and describe the inundation database created for the Lower Balonne floodplain in the Murray Darling Basin.