Protestors associated with the Idle No More movement disrupted traffic to the Ambassador Bridge Thursday. The disruption was planned from 11a.m. to 2p.m. While disrupting traffic may seem harmless enough, it comes with substantial costs.

While the symbolism of shutting down the bridge will likely have more impact on the movement (potentially to their detriment) than the associated costs, they are worth bearing in mind. First Nations people have a right to be angry about conditions on reserves, and have a right to express their frustration and seek to ameliorate their communities through the political system. But imposing costs on the broader economy is not the way to build sympathy for the cause of First Nations people.

The Ambassador Bridge is the busiest border crossing in Canada, carrying 42 per cent of all of Canada's trade with the United States. More than 8,000 commercial trucks cross each day. According to a study commissioned for the Canadian Department of Foreign Affairs and International Trade, the cost per hour delay to a trucking company is $40 per hour for each truck.

This includes only the costs of keeping the truck and driver on the road, not the costs of late deliveries and so forth. Not having access to the number of vehicles crossing at each hour, or the degree to which protesters slowed traffic makes it difficult to estimate the direct cost to the trucking industry. As a rough estimate, we'll assume that the three-hour planned disruption slowed traffic by 50 per cent, and that those three hours should have accounted for 20 per cent of daily traffic. That amounts to a 1.5 hour loss for 1600 vehicles.

Moreover, lets assume that another 20 per cent of truck traffic faced one-hour delays (since the backlog at the border takes time to clear), and another 10 per cent faced 30 minute delays, since the effect of prior delays cascades, disrupting later traffic. This would mean that the initial delays accounted for 2,400 hours of lost time, the second wave of delays 1600 hours, and the third wave 400 hours. The total time lost from delays would add up to 4,400 hours. At $40/hour, the direct cost to the trucking industry would amount to $176,000. A full blockade for that duration would have cost well over twice that amount, as delays would have cascaded further.

While $176,000 may not be an earthshattering number, it does not include any costs incurred by companies as a result of delayed deliveries. Assembly line delays can be costly for auto manufacturers for instance. Moreover, it doesn't impute a cost to the value of time lost by Windsor driver, or the cost of having a police presence. But it does highlight the fact that such disruptions are not free. While traffic stoppages don't create the climate of fear that results from protesters smashing in storefronts, they can be more costly under some circumstances. The damage from blockades just happen to be invisible.

First Nations have legitimate channels for protest and for dialogue with the government. They should focus on these avenues, rather than disruptive protests. Otherwise they risk alienating the rest of the public, and undermining their own bargaining position.

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