OTTAWA — A new study challenges a widely held view that expanding roads and highways inevitably leads to more traffic and greenhouse gas emissions.

The Conference Board study — titled Build It and Will They Drive? Modelling Light Duty Vehicle Travel Demand — shows that building roads and highways at a rate that matches the growth in the driving-age population does not significantly increase road usage by motorists.

Population density has a greater effect on
driving habits than limiting construction

It concludes that, in addition to population density, measures such as congestion tolls (similar to those in London, U.K.) have a greater effect on driving habits than limiting construction of roads and highways.

“Where people live is the most significant factor in determining how far they drive. A major part of the solution to Canada’s transportation challenges is more dense urban development, so people live closer to their workplaces and the services they use,” said John Roberts, director, Environment and Energy.

The authors claim their report is unique because it’s the first in Canada to test for evidence of whether new road construction causes Canadians to choose to drive more.

In addition, the study incorporates socio-economic factors into the analysis, including: the share of Canadians residing in urban areas, vehicles per person of driving age, population growth, real per capita disposable income, established driving habits and the price of gasoline relative to the price of local transit.

Also, the study is the first public analysis of personal vehicle use to incorporate data from the new Canadian Vehicle Survey.