Many benefits come with living in a growing modern city like Perth; from economic opportunities to a more cosmopolitan ‘vibe’. However, there are also challenges that come with bigger city life.

One of the most contentious issues is traffic congestion. Put simply, more people means more traffic, and in times of rapid expansion, more traffic means more congestion. Managing congestion is important, and challenging, not least because there is no simple agreed definition of when congestion starts to become a problem. And everyone who travels, by road, or bike or public transport has their own experience and their own ideas about the problem and the solution.

Decisions made by many government organisations impact on congestion. These include new land releases for residential development, locations of major employment hubs, public transport and road infrastructure choices, the availability of bike paths, and parking availability.

This audit looked at one important part of government activity to manage congestion. Main Roads is responsible for developing and maintaining major roads in metropolitan Perth. As such, it has a prominent role in dealing with congestion. We assessed whether Main Roads had good information about congestion, how it prioritised congestion projects, and whether its projects were on time, on budget, and achieved the desired outcomes.

I found that Main Roads is undergoing significant organisational change and this will affect how it manages congestion. It is moving from an agency that builds and manages assets to a road network manager responsible for traffic flow. When completed, this will bring it into line with better practice in managing congestion, and should also improve the information provided by Main Roads to other policy makers.

I also found that Main Roads is delivering congestion projects on time and budget and with effect. However, the way Main Roads prioritises its project choices was not always clear, and as a result, I could not be certain the most effective or efficient projects were getting priority. Also, the capacity to effectively prioritise was limited by having comprehensive performance information available for only a small portion of the freeway network. Finally, Main Roads and other key transport agencies including the Department of Transport had not determined clear congestion targets, outcomes or performance levels.

Overall, I believe Main Roads is moving in the right direction and although the changes will not be easy to bed down, they are necessary to optimising the performance of the road network and to addressing Perth’s traffic congestion.