Lets examine that, shall we?
First, according too
this from 2005, about 39% of Airdrie residents over age 15 commute to Calgary for work or school. Now,
here is the 2008 Airdrie census. Assuming the 4500 or so people who did not respond to the census are representative of the age breakdown of those who did respond, that represents about 28,000 Airdronians over the age of 15.
Thus, if 39% of that population commutes to Calgary, that represents approximately 11,000 people commuting to work.
Next, lets assume that commuters average about two people per vehicle. There are a lot who drive singly in their cars, but there are also a few packed buses that go downtown every day, so this seems a fair estimate. That would equal approximately 5500 cars per day from Airdrie.
According to the City of Calgary, using
2006 data (most recent available), 134,000 cars per day, on average, pass Deerfoot at McKnight Blvd. Since those 5500 Airdrie cars are going both directions, Airdronians account for 11,000 of that total, or 8.2% of total volume. The real number will, in fact, be less because many Airdrie drivers get off Deerfoot at Country Hills to get to the C-train. Also because I am using 2008 Airdrie population with a 2006 traffic pattern. Airdrie is growing hugely, so using 2006 population with that map means the actual percentage of drivers at that point from Airdrie might be as low as 6.5%.
By comparison, 48,000 vehicles per day are reaching Deerfoot at McKnight from Beddington - 35.9% of the total traffic flow at that point. Thus, drivers from NW Calgary alone are responsible for over four times the traffic volume that Airdronians are.
Thus, I rest my case. The traffic problems you suffer through every morning are because of the bottleneck at Beddington, not because people from Airdrie are stealing your spot on Deerfoot.