A groundbreaking federal study has calculated the "social costs" of operating cars, trucks, planes, trains and boats across Canada at up to $40 billion a year.

The study for the first time attempts to put a national price tag on the unwanted byproducts of transport, that is, accidents, pollution, congestion, noise and greenhouse gases.

The findings, released without fanfare in late August, are the result of a five-year project that drew widely on experts from academia, industry and the provinces.

Using statistics for the year 2000, the task force found that the often-hidden social costs for all modes of transport ranged between $24.4 billion and $39.5 billion — or up to 17 per cent of the total costs of transport that year.

Automobile accidents represented the largest single source of social costs. Researchers determined that a Canadian life was worth about $4 million on average, based on insurance and court settlements, and that fully disabling accidents cost an average of $260,000.

Altogether, road accidents accounted for an estimated $16 billion in social costs in 2000, compared with just $370 million for accidents involving planes, trains and boats combined.

Road congestion and air pollution on the roads cost another $5 billion each, while greenhouse gases emitted by road vehicles cost $3.7 billion, based on a carbon-trading market price of $29 a tonne.

Noise costs, difficult to estimate, were pegged at just $220 million.

Congestion was generally measured in terms of productive time lost while drivers were idled by traffic jams.

The air, marine and rail modes accounted for just a fraction of these social costs, the study found.

The worst social impact of aircraft was in the amount of greenhouse gases emitted, calculated as costing almost half a billion dollars. The worst impact in the rail and marine sectors was air pollution, each also calculated at about a half billion dollars.

Lack of data prevented the researchers from estimating congestion costs for the rail, marine and air sectors.

The authors caution that the complex methodology is a still work in progress but that "another tool has been added to the analytical toolbox of transportation analysts." Further related studies are planned.

A spokeswoman for Transport Canada said the $1.4-million study was designed "to allow for a better understanding of the relative full costs of the different modes of transportation.

"Those social costs are borne by all members of society," Maryse Durette said in an interview.

A transportation expert who was consulted throughout the study praised the results.

"I have been quite impressed at the care taken in the analysis," said David Jeanes, spokesman for Transport 2000, a non-profit research and advocacy group.

"We urgently need this `level playing field' information for governments to make intelligent decisions about investment among the various modes [of transport].

"It has been a very challenging exercise and cannot be absolutely complete and perfect, but I think the report is a good one."

The study also tried to compare social costs in Canada with other countries. Canadian accident costs, for example, were generally in line with those in Britain and Europe but were less than half the level for the United States.

"The high transportation accident cost in the United States can be explained in part by the higher rate of transportation accident related death observed in that country ... more than 15 per 100,000 inhabitants compared to about 10 per 100,000 for Canada," the report says.

On the other hand, the estimated costs of transportation "noise" in Canada were much lower than in any other country, perhaps reflecting a less-dense population in Canada or differing methods of determining the cost, the authors said.

Noise costs were generally calculated as the damage to residential property values from the constant sound of vehicle traffic, trains and aircraft.