A great piece from
the Tri-City News:
It has become almost an accepted truth that building additional highway capacity is bad for the environment. Many people believe the more highways we build, the more cars and trucks we will put on the roads – and, therefore, the more greenhouse gases will be emitted.
Has anyone actually taken the time to study whether this is the case?
Until recently, the answer has been no but two new reports, one groundbreaking in terms of its research focus, helps to shed some light on this important question.
In December 2006, the Conference Board of Canada released a new research report titled “Build It and Will They Drive?” The purpose of this report was to identify the determinants of “induced travel,” which is defined as the increment of new vehicle travel on a particular roadway. The report was groundbreaking in that its methodology was based on two never-before used sets of data: one, a series of socio-economic variables and two, use of the Canadian Vehicle Survey, which is a new Statistics Canada measuring tool.
The results were surprising, even to the researchers who produced the report.
What this Conference Board report discovered was that there is no statistical relationship between induced travel and the capacity of highways available. In other words, there is no truth to the notion that more highways equals more cars, which equals more greenhouse gas emissions.
Instead, the Conference Board found the largest determinant of travel demand is population density (i.e., growth in urban and suburban development), followed by average wealth – the notion being that as Canadians become richer, they can afford the costs associated with driving additional vehicles.
Other factors having an impact on driving demand are population growth, past driving habits of individuals and the price of gasoline relative to the price of local transit.
The Conference Board (www.conferenceboard.ca) looked at the influence of an increase in the number of lane kilometres available to the local population and concluded that increased highway capacity had no influence on induced demand.
This report alone suggests building more highways does not lead to an increase in greenhouse gases. But in addition, a new report released in January by McElhanney Consulting Services Ltd. of Surrey makes a case that additional highway capacity can play a key role in reducing greenhouse gas emissions by reducing overall highway congestion.
The McElhanney report used computer modelling and real-life traffic counts to estimate vehicular emissions, including greenhouse gas emissions, at various speeds. The report concluded that emissions are at their highest when traffic moves at speeds between 5 and 15 km/h – standard stop-and-go congestion speeds. At these speeds, CO2 emissions in a typical car are close to 40,000 grams per mile travelled. But when speeds increase to approximately 50 to 55 km/h, emission levels drop to approximately 16,000 grams per mile travelled.
What this suggests is that stop-and-go congestion is responsible for emissions that are approximately three times higher than cars travelling at more regular speeds. The clear implication is that a reduction in congestion is desirable from a greenhouse gas reduction standpoint.
If we assume for a moment that driving habits are not likely to change in the immediate term, the logical choice for reducing congestion is to increase highway capacity – and as the Conference Report suggests, this can be done without any accompanying induced demand that would negate any effects of lower congestion.
The implications of these reports are clear. The old stereotype that more highways equal more pollution is unfounded. Instead, a strong case can be made that additional highway capacity plays a key role in reducing congestion, which in turn has a clear role to play in reducing greenhouse gas and other pollution emissions. This is an important conclusion for policy makers at all levels, particularly as Canadians demand action on reducing greenhouse gases while at the same time demanding safer, more reliable transportation. Added highway capacity would seem to achieve both goals.
Jeff Morrison is executive director of the Road and Infrastructure Program of Canada (TRIP Canada) and director of government relations and public affairs, Canadian Construction Association
(www.cca-acc.com).
5 Comments:
Hmmmm....
Looks like this is an op-ed column from the folks who profit from road construction.
If induced traffic is a fallacy, why does Kevin Falcon accept it as a serious danger to be avoided and why does Gateway forecast the twinned Port Mann would recongest in as little as five years without tolls/TDM?
I suspect that Minister Falcon would prefer to patronize Gateway opponents while collecting revenue with tolling. This is a win/win in the political realm.
The argument of Induced Demand is a fallacy that is promoted by special interest groups who have other, self-serving agendas!
Conference Board Report and McElhanney Consulting sound like fishy sources for these kind of reports. Give me a report or study from an independent university researcher and I would think there's more value. You always have to look behind the report to the reporter to see what their bias is. Definitely looks like groups that benefit from road construction are behind this report. In fact, McElhanney is one of the companies working on the Golden Ears Bridge and could stand to benefit from additional highway projects in the Lower Mainland. Even the author of the article is somebody with a vested interest.
The writer's following statement is already a BIG RED flag: Has anyone actually taken the time to study whether this is the case?
Until recently, the answer has been no but two new reports, one groundbreaking in terms of its research focus, helps to shed some light on this important question.
A quick Google search on the topic of induced demand and highway construction pulls up many reports on the topic. The author's absolute statement on "no reports until recently" brings an instant sense of skepticism.
Visit the Google Scholar link here and you be your own judge as you read through the articles: (http://scholar.google.com/scholar?q=induced+demand+highway+construction&hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=6Hk&um=1&oi=scholart)
There does need to be a degree of increased road and bridge construction, I just don't think implementing ALL of the Gateway Project is a good idea.
I think whoever wrote the piece for the Tri-City news did not actually read the conference bopard report carefully enough
Firstly:
> The purpose of this modelling exercise is to test the
> hypothesis that increases in lane-kilometres per capita,
> independent of any other influences, lead directly to
> induced travel. In other words, physical improvements
> to the road network, which result in freer-flowing traffic
> and reduced travel times, induce individuals to drive more.
> The model does find a weak relationship. It finds
> that for every 1 per cent increase in lane-kilometres,
> there is a 0.49 per cent increase in vehicle-kilometres
> traveled by light trucks and a 0.26 per cent increase in
> vehicle-kilometres traveled by cars, which is in the range
> of what had been predicted by previous research. However,
> the significance of these estimated coefficients is weak.
> They fail to meet established standards for inclusion in
> an econometric model (falling just outside the 80 per cent
> confidence interval for cars and the 90 per cent confidence
> interval for light trucks).
> There is no statistically significant relationship
> between lane-kilometres and vehicle-kilometres
> per capita in Canada.
Now what has happened here is that the use of national data has been
carefully selected to make sure that a commonly observed phenomenon in urban areas is less impressive when you add lots of low use rural roads.
The relationship may not be statistically significant at the national level (though we could get into the data set if you must as it has its limitations) but that does not mean it is not very significant at the regional level. Given the population density of Greater Vancouver compared to Canada as a whole, it would be very surprising if this were not so.
(And, of course, no one ever claimed a relationship between "lane kilometres per capita" on a national basis and propensity to drive. What is currently observed is that there is congestion in urban regions which indicates "supressed demand". Some trips are not being made because it
is simply not worth the hassle. But, if some trips could be "priced off" the system, by the use of congestion charges, more worthwhile trips would be made. )
And anyway the study goes on
> the model doesn’t suggest that continuing to build road
> networks—and, by extension, facilitating urban sprawl—
> as Canada has in the past is an effective strategy for
> limiting greenhouse gases from the transportation sector
> either. For example, urban planners must consider the
> opportunity cost of the “business as usual” strategy of
> suburban development. There is a limited area of land
> available for cities to provide the services their citizens
> demand. When land is allocated to transportation network
> expansion it cannot be used for other purposes,
> such as recreation, housing or commerce.
Which is not exactly what the News wanted to read, I suspect.
I will not repeat here what I wrote in my blog - but it deals with
traffic generation and its converse - traffic evaporation when roads are
removed in urban areas
http://stephenrees.wordpress.com/2006/11/20/heart-and-soul-of-the-city-conservation-guardian-unlimited-environment/
and provides citations and links which show that far from being "a myth"
it is one of the longest established and best demonstrated principles in
the field of urban transportation planning.
Stephen Rees MSc (Econ) MITE
ahem, the authors/reporters credentials are...
Jeff Morrison is executive director of the Road and Infrastructure Program of Canada (TRIP Canada) and director of government relations and public affairs, Canadian Construction Association
need I say more....
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