The number of credits has been scaled back, weightings have been made more adjustable and modifications have been made to make the system more accessible to smaller projects under a changed and updated infrastructure sustainability weightings scheme in Australia.

In a recent announcement, the Infrastructure Sustainability Council of Australia has unveiled an updated version of its Infrastructure Sustainability Rating Scheme, the first such update since the scheme was launched in 2012.

ISCA chief executive officer Antony Sprigg said the changes concern three main areas, and have been designed to give the scheme a tighter focus with a greater emphasis on outcomes.

First, the number of credits has been pared back from 52 to 44, a move which was designed to address a situation in which certain credits and credit requirements had been identified as necessitating the collection of information which was of relatively low practical value in terms identifying and implementing critical sustainability opportunities.

Second, a new system of adjustable weighting has been established which is designed to afford a greater level of weighting on the IS rating scorecard to issues which are particularly relevant in terms of sustainability opportunities for the particular asset in question. This is designed to address a previous situation under the original version of the scheme whereby weightings were determined according to a preset national approach notwithstanding the fact that opportunities available for sustainability gains vary according to factors such as the geographic location and climate for each asset in question.

Finally, some minor modifications have been made in terms of customised credit and guidance for projects of a value of less than $20 million. This was done in order to recognise that some of the requirements were less applicable to projects of a smaller scale and also to make the scheme more accessible to smaller projects.

Introduced in 2012, the IS rating scheme aimed to provide a comprehensive tool in terms of the design, construction and operation of infrastructure in Australia.

Sprigg said the changes were made after consultation and were implemented with the intent of increasing the value of the tool in terms of identifying opportunities for more sustainable outcomes.

Over time, he says, ISCA would like to develop a Version 2 of the scheme (the recently introduced version is numbered 1.2) which may encompass a greater level of focus upon a wider context of factors in realms such as social, procurement and workforce considerations.