A review of flow estimation by runoff routing in Australia – and the way forward

ABSTRACT

Flood hydrograph estimation in Australia is mostly undertakenby a class of models known as runoff routing models. These models have in common the sub-division of the catchment into a number of sub-catchments, with the application of excess rainfall to each sub-catchment and the routing through a series of nonlinear storages representing the channel flow through the catchment. The first Australian runoff routing model was developed in the 1960s, and there have been numerous models developed that contain the same basic structure, with enhancements. With the release of Australian Rainfall & Runoff there were significant changes in the way design floods are estimated in Australia, with flood estimation by runoff routing beingmodified to include a joint probability approach rather than a design flood approach, so that the variability and interaction of flood-producing factors are better allowed for. This paper reviews the development of runoff routing within Australia, from the original 1960s model to joint probability, and identifies issues associated with the models, including self-consistency and the limitation on the runoff processes that can be modelled. The required features of a model that address the limitations of current models are described.

KEYWORDS:

• Hydrology
• models
• flood
• runoff
• process

Additional information

Notes on contributors

David Kemp

Dr David Kemp was, until his retirement from full time employment, employed as the Principal Hydrologist by the South Australia Government in the Transport and Infrastructure field.  He has more than 35 years’ experience in South Australian hydrology and stormwater management and has a commitment to furthering knowledge of both flood hydrology and urban runoff quality management. He has been for the last eight years an Adjunct Senior Research Fellow in UniSA STEM, University of South Australia, and is continuing his research into runoff routing models, arid zone hydrology and in the implementation of Water Sensitive Urban Design, particularly relating to the hydrological changes associated with infill development. Dr Kemp has a PhD in engineering hydrology, is a Fellow of the Institution of Engineers, Australia, and a Chartered Professional Engineer. He has also been awarded the Stormwater SA chair’s award for his contribution to the stormwater industry in South Australia.

Trevor Daniell

Associate Professor Trevor Daniell holds an Honorary Research Fellow position in the School of Civil, Environmental and Mining Engineering at the University of Adelaide where he had been an academic for 20 years. He was previously an Engineering Hydrologist and Manager within the Australian Government for 18 years, working on water supply design and operations, flood forecasting, flood and drought management, environmental and water resource investigations in Australia, Indonesia and the Pacific. His contributions to hydrology and water resources have been acknowledged with awards such as Crawford H Munro Orator (2008), “Distinguished Champion in Hydrology for South East Asia and the Pacific in commemoration of the 50th Anniversary of the UNESCO International Hydrological Programme in Asia and the Pacific„ (2015), and with the RJN Franki (1974), GN Alexander (2002) and Warren (2004) medals for best publications. Associate Professor Daniell is a Member of the Australian UNESCO IHP Committee, Past Chairman UNESCO IHP Steering Committee for SE Asia, and Past Chairman of FRIEND Intergroup Coordinating Committee UNESCO IHP. He currently sits on the Board for Stormwater Management Authority in South Australia and is Associate Editor of the Australasian Journal of Water Resources.