600% Increase in Congestion Ahead

The table on the next page is from the 1991 "Road Transport Future Directions" Study, undertaken by consultants in 1990-91 for the NSW Roads and Traffic Authority. It contrasts two different futures for a state of New South Wales when population reaches the 8.5 million mark (expected to have been about 20-30 years beyond the time when the study was done, or around 2016 give or take a few years). This table presents the message of that study in its most condensed and concentrated form : if we carry on as we are, we face a much less pleasant future than if we change our ways.

The study had been set up to identify and assess the strategic options open to the RTA (which, at the time, had been born out of a major re-organisation of government departments about two years previously). The study found that there was only one option - "to be or not to be", in effect.

The strategic issue was how far and how fast government was prepared to move in the direction labelled by the study "integrated demand management".

This message, and the predictions in this table, have entered Sydney folklore and are still being quoted today. Indeed, it is the appearance of a full-page article in the Sydney Morning Herald literally today (this written 16 May 2000) that prompted these thoughts.

The article opens by quoting most of the figures from the "Current Trends" column of the above table.

Why has this study endured the test of time so well ? I suggest there are at least four reasons-

• It delivered a message that people wanted to hear, for urban and rural interests alike. In particular, for Greater Sydney, it strongly suggested the benefits of greater attention to public transport enhancement.

• It delivered it in an authoritative way : it was the product of a years work by a team of experienced professionals with appropriate analysis tools and support from some thirty specialist investigations.

• The analysis procedures have never been repeated, updated or replaced by other work.

• It delivered it in a memorable way - the broiling froth of inter-connected and complex issues was summarised in the table reproduced above. The predicted increases in congestion and pollution have entered the public psyche. The prediction of the public budgetary deficit worsening by $1.35 billion per annum if nothing was done probably concentrated the minds of many government officials, too, although they made less noise about it.

As part-author of the report and the team member largely responsible for addressing urban transport issues within that study, it is very gratifying to have provided such substantial input to debate in the community.

But ...

It would be even more gratifying if the findings and arguments of that Study were reported accurately.

For a start, the table related to the performance of the state of New South Wales, not just the city of Sydney (except where not relevant for the whole state, eg time lost to congestion).

The performance of Sydney specifically was also reported in the study documentation, but not in the same condensed format. Advocates will find that it presents an even bleaker picture of our possible urban future under "Current Trends".

The next page shows possible futures for Sydney rather than for New South Wales.

The Herald article introduced its statistics from the Study with the remark that "The RTA's 1991 study Road Transport - Future Directions predicted that "if car use continues unabated by 2016 there would be : (the Current Trends statistics then quoted)." My emphasis.

Well, no, it didn't, although many people who look at the summary table without reading the report think that it must have. No, not at all. Life is more complicated than that.

What it said was that these outcomes would come to pass if a strategy of continuing with current trends is followed. And the circumstances involved were specifically described.

• land use : continuation of current [as seen in 1990] trends and practice in terms of urban form and structure and the dominance of Sydney relative to other areas;
• pricing: continuation of current road user charges (except for 3x3 State levy);
• network development: the development and management of urban networks with priority for public transport needs, and the enhancement of rural road infrastructure appropriate to growth in demand;
• public transport: the necessary enhancement of urban public transport to cope with a greatly increased task.

In other words, the predicted performance comes from a public transport oriented future, not a car oriented future. The 19% predicted increase in public transport's mode share under current trends is seldom mentioned by anyone.

It is the expected growth in car travel, even after public transport has taken a much enlarged share of a much enlarged market, that is responsible for the high rise in time lost to congestion on a road network that has not been correspondingly enlarged. Bus priority measures may have re-allocated some existing capacity, further fuelling congestion for those in cars.

And that doesn't mean, as many might intuitively expect (and my opening illustrations misleadingly suggested), that it will take seven times as long in future to get through today's well-known trouble spots in the Sydney network. It is much more a question of lesser congestion spreading over a much greater portion of the whole road network.

This leads thinking into more difficult areas than would the relatively easy solution of ameliorating our congestion and pollution by heavy public transport investment.

Why, then, did the study interpret current trends in this way but still come out in favour of public transport as a key element of urban strategy ?

The scope of the study was broad, and its method was one of scenario testing. The scenarios were defined by various combinations of land use futures, pricing futures and transport network futures.

Two contrasting transport network futures were compared, resulting from strategies of demand satisfaction (oversimplifying, a road construction future) and demand management (including public transport development in urban areas).

Didn't that give a clear answer ? Yes and no ...

The study did not have the resources to test all possible combinations, and in particular did not test a scenario with all the other settings of the "current trends" scenario but network demand satisfaction rather than demand management - in other words, the much-demonised "road-building future". With no change in current pricing policy, this was seen as an unlikely, inconsistent, irresponsible and unaffordable combination of policies and was not tested. The Study was not seeking ways of making things worse than they would otherwise be !

Had such a scenario been tested, I would expect that it would have been in general the worst performing - with the financial performance particularly appalling - but the congestion measure would have improved over that shown by the "Current Trends" scenario. If, irrespective of other issues, you add the roads to satisfy the demand for future car use of course you will reduce future congestion, for a while at least - though you may destroy Sydney in the process.

The measures reported in the summary table were a selection from a suite of over 70 measures produced by the analysis.

The best performing scenario (the second column of the tables above) also involved demand management.

The study drew its conclusions in great part from detailed pairwise comparison of the scenarios tested, teasing out what worked well and what didn't. Demand management futures gave generally preferable outcomes to demand satisfaction ones, though the reasons are much more complex than the simple assumption of advocates that public transport development will reduce congestion and pollution.

The degree of support for the conclusions of the Study is welcome, even when people have not quite reached them by the same route.

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