Editor:
There is not a single sentence or word about fire egress in the 144 pages of the 2021 Three Sisters Mountain Village global transportation impact assessment. Likewise, there is no sentence or word in the Town of Canmore’s 2018 Integrated Traffic Plan. You might expect a discussion in the TSMV’s 2020 wildfire risk assessment plan, but you won’t find one other than it noting there are two points of egress without any evaluation of adequacy.
The present circumstance of limited and insufficient roads for emergency egress from town in the event of a wildfire is probably dire. To test it out, the Town could conduct a scheduled mock fire egress drill to see how long it takes to get everyone out of town.
But what effect will doubling the number of people and vehicles in town have on this? Will it double the time for egress? No. The relationship is logarithmic, not linear. A chart from “Traffic Stream Characteristics” by Fred Hall shows this. This is a highly cited and respected traffic engineering study.
Shock waves and phantom roadblocks are resultant phenomena from increased volume. Under panic, this would be much worse.
In other words, at a certain point, merely a 15 per cent increase in the number of cars may cut the traffic flow rate in half; a 50 per cent increase may cut the flow rate to one-eighth; and a doubling of the number of cars may essentially bring the flow rate to near zero.
If you go into any commercial building such as a restaurant you will see posted inside the door a little plaque stating the maximum occupancy for the building. That is based on safe fire egress. The same absolutely must apply to a town situated at risk for wildfire.
Aside from the wildfire scenario, the effect of the slow-down of transport must be considered for other life-safety situations, namely fire engines, ambulances and police cars reaching emergencies. What may presently take eight minutes from downtown to Three Sisters Parkway, may in the future take over an hour.
In a previous letter to the editor, a resident in Banff with its much smaller population, said she must allow 45 minutes to take her grandkids to daycare across town. And the crosstown distances in Canmore are over four times that in Banff.
Based on this, TSMV’s plan to nearly double the town’s population should’ve been denied. The same is true for all other developer’s plans to increase the traffic volume.
Ken Hantman,
Canmore
