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Vehicle Travel Time Savings

Here are some notes I wrote in 2015 on (Vehicle Travel Time Savings) VTTS and Westconnex …

Level of Service on Westconnex after Stage 3
SMPO. 2013, “[Westconnex] Business Case Executive Summary“, State of NSW.

Regarding the Herald article ‘Sydney motorists unwilling to pay for more toll roads: study’ by J. Saulwick

‘The findings by David Hensher, the director of the Institute of Transport and Logistics Studies at Sydney University’ and ‘Professor Hensher is an expert in transport forecasting who also served as an independent reviewer of patronage forecasts on the $15.4 billion WestConnex.

According to Professor Hensher’s study, a typical industry estimate of the value motorists put on saving travel time is about $22 an hour.

But in his empirical study of Sydney motorists, drivers value their travel time at no greater than $12 an hour and, for new motorways, possibly closer to $6 per person per hour.’

Jacob Saulwick. 2012-11-11. “Sydney motorists unwilling to pay for more toll roads: study.Sydney Morning Herald, Fairfax Media LtdNine Entertainment Co. gkv5b3.html

The value motorists place on saving an hour travelling (VTTS) is the value on which the entire Westconnex modelling rests. The Business Case is based on the Value of Travel Time Saved.

From ‘WestConnex – Sydney’s next motorway priority – October 2012’ by Roads and Maritime Services (RMS) & Infrastructure New South Wales (INSW)

Costs and funding

The high-level target capital expenditure estimate for WestConnex, including property acquisitionand construction is approximately ($2012), assuming an optimised design configuration and a procurement and delivery approach that learns from the best of international experience. Should WestConnex be adopted by the NSW Government, further work is required to refine this estimate.

The project generates a benefit to cost ratio (BCR) of over 1.5, meaning economic benefits to users are over 1.5 times the costs. This analysis provides compelling support to prioritise the project from an economic perspective.

RMS, INSW, TfNSW. 2012-09-25, “WestConnex – Sydney’s next motorway priority“, State of NSW. p 5

The calculated benefits are predominantly network-wide travel time savings which represent greater than 90% of the transport benefits, with the remaining benefit comprising reductions in distances travelled, fuel efficiencies and road safety improvements.

RMS, INSW, TfNSW. 2012-09-25, “WestConnex – Sydney’s next motorway priority“, State of NSW. p 27

The total benefits were predicted to be about $13.5 billion and yet 1 year later it was $15.4 billion.

From the “WestConnex – Business Case Executive Summary – September 2013” by the Westconnex Delivery Authority (WDA)

Table 4: Benefit Cost Analysis result
SMPO. 2013, “[Westconnex] Business Case Executive Summary“, State of NSW.

The total benefits was predicted to be about $13.5 billion and yet 1 year later it was $15.4 billion. Worse the reliability and operating cost benefits have increased from 11% of the TTS benefits to 20% of the TTS. The higher the VTTS the less travel time savings to get a good business case.

Hours of Savings to Make $15 billion in Benefits

Time Travel Savings $15,410,000,000

 VTTSHoursVTTS  Hours

RTA in M5 Transport Corridor Study Preliminary overview report.

Value of travel time savings of $14.1/hr (2004 dollars).

RTA. 2009. “M5 Transport Corridor Study Preliminary overview report“, State of NSW.

Adjusted for inflation using the RBA calculator that was $18.51/hr (2004 dollars). However, it should be adjusted by Average Weekly Earnings, which rose faster.

That is explained in the National Guidelines for Transport System Management Road Parameter Values [PV2]. Warning these are national values, which are lower than those used just for Sydney.

3.1.1 Travel time values for light vehicle occupants

The value of travel time for the occupants of passenger cars was updated to 30 June 2013 using the change in Average Weekly Earnings (AWE) (Australian Bureau of Statistics 2013b). The AWE for full- time ordinary adult workers in Australia as per May 2013 ($1,420.90 per week) was updated to June 2013 using the CPI and was calculated at

$1,423.67 per week or $37.46 per hour assuming a 38 hour week. As in previous Austroads unit values updates (Austroads 2012a), private travel time was valued at 40% of seasonally adjusted full time AWE for Australia (Austroads 1997), or $14.99 per person – hour (i.e. 40% of the AWE).

For business car travel, the value of travel time was assumed to be 129.8% of AWE (135% of full time AWE less 5.2% for payroll tax), assuming a 38 hour week. This methodology was in line with Austroads (1997) 3 and subsequent unit values updates (Austroads 2012a). On this basis, business car travel was estimated at $48.63 per person- hour. These values are contained in Table 3.4

Transport and Infrastructure Council. 2015. “National Guidelines for Transport System Management in Australia“, Council of Australian Governments, Commonwealth of Australia

In the “WestConnex M4 Widening – Traffic and transport working paper” for SSI 13_6148 (WestConnex M4 Widening – EIS) there is no given value of VTTS. Worse there are some big caveats.

Freight vehicles choosing to avoid the WestConnex toll are likely to be made up of those vehicles where the perceived value of travel time saving is less than the cost of the toll. This behaviour is incorporated into the WRTM based on the Value of Travel Time Savings surveys undertaken for heavy commercial vehicles in 2012 (refer section 5.2).

RMS. 2014-08. “WestConnex M4 Widening – Traffic and transport working paper“, State of NSW. Page 175

Starting on Page xiii

‘The assessment of operational traffic and transport impacts of the project on road transport were evaluated using traffic demand data from the WestConnex Road Traffic Model (WRTM) which was developed to forecast road traffic demands for the WestConnex scheme including the M4 Widening project. The WRTM has two elements: The base demand model – which is based on the Sydney Strategic Transport Model (STM) operated by the Bureau of Transport Statistics (BTS) and used for projecting travel patterns in

• Sydney, Newcastle and Wollongong under different land use, transport and pricing scenarios. The base demand model can account for changes in land use, trip distribution and mode choice as well as producing vehicle traffic demand forecasts for peak and off peak periods.

The toll choice assignment model – models the range of driver behaviour to toll strategies and forecasts the traffic choosing to use toll and non-toll routes during peak and inter-peak periods.

The WRTM model was developed and calibrated to current observed travel behaviour, then validated against 2012 Sydney-wide travel behaviour. It was then adjusted to reflect driver behaviour on toll roads observed in the Value of Travel Time Surveys (VTTS). Future demand was forecast by applying the model with future year traffic growth assumptions from the STM.

ibid. Page xiii

Page 101 under 5 Traffic Forecasting Approach

Stream 1 of the WRTM was a fully functional toll choice model of similar design to the final WRTM however some parameters were adopted from recent studies undertaken in Brisbane as suitable data was not yet available for Sydney. This approach provided a functional model for use in the preliminary Business Case than would otherwise have been possible in the available time. The Stream 1 model was commenced in January 2013 and completed in April 2013 in time for use in the preliminary Business Case.

• The revisions made for the Stream 2 model essentially replaced the Brisbane parameters with Sydney data and refined transport networks and demands. Survey data for Sydney was collected between March and May 2013 to determine Sydney drivers’ willingness to pay tolls (Value of Travel Time Surveys (VTTS)) and subsequently analysed to replace the Brisbane-based data initially used in Stream 1. Work was also undertaken to improve the model’s performance with respect to matching observed traffic volume and travel times. The model is currently in the final stages of review by a Peer Review Committee that includes representatives from the WDA, transport planning specialists and academia. The reviewers have approved the use of the Stream 2 WRTM in this working paper. The Stream 2 model was used to produce the traffic and transport assessment as part of this working paper.

The independent review committee included an independent expert Denis Johnston1 and Professor David Hensher of Sydney University Institute of Transport and Logistics Studies.

ibid. Page 101

Read on to page 104

Available data from a recent project in Brisbane for the Queensland Government was used for the private vehicle VTTS values for Stream 1. This data was supplemented by VTTS data from commercial vehicle surveys conducted by Jacobs SKM in Sydney in late 2012. The data collection and analysis methods were similar and compatible for these two VTTS studies.

To support the development of the WRTM toll choice model, further similar and compatible project specific VTTS surveys for private vehicles in Sydney were conducted in March and April 2013 to inform the toll choice modelling. Analysis of these surveys was not available for the Stream 1 delivery which was required for the Business Case in September 2013 but is included in Stream 2 modelling.

ibid. Page 104

Which recent toll-road project? One that AECOM worked on? The bankrupt Aiport Link, or Clem 7?

On Page 211

The assessment has found that under the distance based toll regime to be adopted by the WestConnex scheme, traffic volumes could rise on parallel routes such as Parramatta Road despite the widening of the M4 Motorway. Under the M4 Widening scenario, travel times on Parramatta Road increase slightly due to drivers avoiding the toll.

Diversion of traffic from the M4 Motorway due to the previous toll arrangement (gauged by the change in traffic after the toll was removed in early 2010) was less than the amount that model is predicting under similar conditions.

ibid. Page 211

There was an additional 1000 vehicles added to peak hour by the induced traffic from the removal of tolls on the M4. However, their model doesn’t support induced traffic analysis.

The below paragraph means poor people.

Furthermore, the road users most likely to avoid the toll would be those customers whose perception of the value of travel time is lower than other road users and from markets that are better served by other modes of transport or are not a target market of WestConnex.


The M4 East EIS till uses the same values. See Appendix G Page 4-3

Private car driver stated and revealed preference VTTS data collected for this study in early 2013. Commercial vehicle stated preference VTTS data collected in late 2012.

RMS. 2014-08. WestConnex M4 East Environmental Impact Statement – Appendix G, State of NSW. Page 4-3 and

1 Denis Johnston – Independent Consultant
Melbourne Area, Australia