Waterways Group Index of River Condition

The Index of River Condition (IRC) was developed as a tool for managers to benchmark waterway condition and to assess the long term benefits of rehabilitation programs. The IRC is a modified version of the Victorian state-wide Index of Stream Condition (ISC).  The document initially briefly outlines what the IRC is, and why it was developed by Melbourne Water.

This document details the information systems that Melbourne Water uses to manage their waterway and drainage assets and how such systems generate work orders. The information system is covered in some detail - particularly mapping and data storage. The importance of how analysis at different spatial scales can influence results is stressed.

This document explains how Melbourne Water’s asset management system breaks its many waterway networks and drains into thousands of individual units - which can range from a few metres to several kilometres in length. It covers the attributes that are used to select and assess the condition of individual reach units. Put simply, the length of a reach 'unit' is determined by consistency of the reach condition.

The Index of River Condition was initially developed to rate the condition of rural - not urban - waterways.

Melbourne Water has applied the IRC to as many waterways as possible - including some urban waterways. However to improve the method Melbourne Water is now developing an Urban Waterways IRC.

This document details data requirements for the method and links to the templates used for data storage, retrieval and calculations. Appendix 1 details field data collection methods and associated calculations.

The authors caution that some of the methodology - particularly for urban waterways and drains - contains gaps in terms of how the data is collated to assess condition and inform long term monitoring.