Estimates of congestion costs

ACIL Allen's work for the Audit has estimated that the cost of delays on urban roads was $13.7 billion in 2011. Based on projected population growth and distribution, and in the absence of any new network capacity and/or demand management, the Audit projects the costs of congestion on urban roads will grow to $53.3 billion in 2031.

The ACIL Allen methodology does not account for new investments in infrastructure between 2015 and 2031, apart from infrastructure which is already under construction, or for which a firm funding commitment has been made. Details of these projects are set out in the Veitch Lister Consulting reports for each of the six cities studied.

Table 12 shows this projected congestion cost across the six largest capital cities.

The projected growth in congestion cost for Perth reflects the projected increase in greater Perth's population - from 1.9 million in 2011 to 3.3 million in 2031, or 77 per cent - overlaid on the current Perth transport network. Perth's transport network is heavily focused on the major north-south corridors, especially the Kwinana and Mitchell freeways. This reflects Perth's urban form, which stretches over 100km north and south along the WA coast. These key freeways are already operating at capacity in peak periods, especially on the approaches to Perth's CBD and the Swan River crossings. In this context, the addition of 77 per cent to Perth's population, without a commensurate increase in Perth's transport network capacity, leads to the spreading of peak period loadings throughout the day, and significant growth in the cost of congestion.

Table 12: Cost of road congestion 2011 and projected 2031 ($ billion, 2011 prices)

Source: Infrastructure Australia analysis of data from ACIL Allen Consulting (2014b) and Veitch Lister Consulting (2014a)