Hydrologic modelling practice notes

River system models, developed by Basin states, the Murray–Darling Basin Authority (MDBA) and Snowy Hydro Limited, have been used to inform development and implementation of key water management policies across the Murray–Darling Basin for over 40 years. There are more than 20 of these models, developed using different methods and software. This makes it difficult to link the models for whole of Basin assessments and requires specific software and model expertise for each valley. To overcome these issues, MDBA and the states, together with CSIRO and many others in the Australian water sector, contributed to the development of a common hydrological modelling platform through the eWater CRC between 2005 and 2012. This platform, called Source, is identified in the Murray–Darling Basin Plan as the standard software to use for models underpinning water resource plans in the Basin.

More recently, MDBA, CSIRO and Basin states have worked together to develop a set of practice notes to facilitate the transparent, consistent, and efficient implementation of the Source modelling platform across the Murray–Darling Basin. The content for these practice notes comes from material provided by MDBA and jurisdictions and has been consolidated by MDBA and CSIRO, with the aid of a jurisdictional advisory group.

Some of the practice notes describe agreed modelling conventions, for example, general principles for naming nodes and links. Others describe recommended practices for methods, for example for flow routing and residual inflow estimation. Where practices differ and where the practice has an effect on model results (e.g. flow routing method), a practice based on scientific research is recommended.

The notes do not aim to be overly prescriptive. They aim to provide high-level principles for modellers to follow when undertaking a particular modelling task. It is anticipated that the practices will be adopted and adapted over time as the benefits of working together using agreed conventions are realised. The development of the practice notes has provided a successful forum for jurisdictions to work with the MDBA to facilitate consistency and good practice in building models to support water resource planning.

While the notes address river system models developed using the eWater Source modelling platform, they are relevant and applicable to model development and application in other modelling environments.