Long-term hydrology modelling and analysis in a data limited small catchment in the wet-dry tropics of Australia

Abstract

The Ngarradj catchment in the Northern Territory of Australia has high temporal resolution rainfall and runoff data from 1998 to 2002. These data have been used to calibrate the DistFW and HEC-HMS hydrology models. The ability of HEC-HMS to be calibrated using an extended hydrograph provided a better basis for long-term modelling. The calibrated HEC-HMS model was applied to 20 years of rainfall from within the region, providing a more reliable estimate of flood frequencies of higher magnitudes (> 1 in 5 year events). However, before undertaking this type of analysis, the modeller must have a good understanding of the catchment system and the limitations of the chosen hydrology model.

Keywords:

• Hydrology Model
• DIST-FW
• HEC-HMS
• Flood Frequency
• Northern Australia
• GIS

Additional information

Notes on contributors

G S Boggs

Guy Boggs is currently a lecturer in Geographic Information Systems at the Northern Territory University. Previously, he occupied the same position at the University of Western Australia. In April 2003 he submitted his PhD entitled ‘Application of Geographic Information Systems to the Assessment and Management of Mining Impact’. This project, a collaborative effort between the Northern Territory University and the Environmental Institute of the Supervising Scientist, examined the integration of GIS and geomorphology models (the SIBERIA Landform Evolution Model) for assessing post-mining landform design at the Jabiluka Mine in the Northern Territory. Guy is currently involved in project’s that use spatial techonologies for examining water quality, fire management, natural resource management and carbon modelling in the Northern Territory. Guy is also attempting to develop a research program that will generate information on the salt lakes in the Western Desert’s region of Australia. He is also currently working with Northern Territory schools as they implement new Geography curriculum which includes references to GIS.

D R Moliere

Ken Evans manages the Hydrological and Ecological Processes Program at the Environmental Research Institute of the Supervising Scientist (eriss). eriss is part of the Supervising Scentist Division of the Commonwealth Department of the Environment and Heritage. Ken’s progam focuses on research toward management and assessment of erosion and hydrological impacts resulting from mining in the Alligator Rivers Region of the Northern Territory which, includes Kakadu National Park.

K G Evans

Dene Moliere is an environmental scientist with the Hydrological and Ecological Processes program at the Environmental Research Institute of the Supervising Scientist. He is responsible for the program’s hydrological data base and has considerable experience in the use and application of Hydsys. He has research interests in stream sediment transport, hydrology and landform evolution modelling.