Traffic on the Sea to Sky Highway
What if there was suddenly no traffic moving on the Sea to Sky Highway? What would that indicate about the well-being of local residents? How would local communities be affected? How would maintenance costs decrease? How would businesses change their decisions about future investments?
By asking such an extreme version of the question, we can understand why traffic counts matter. With this in mind, we set out to understand what is happening on the Highway by looking into two way traffic counts at a location just north of Squamish. Below is what we found.
Traffic has increased more than a quarter over the last decade. Approximately 58,000 vehicles passed per week in 2006, compared with 73,000 vehicles per week in 2015. Annually, thats an increase of more than 800,000 vehicles passing! For us this raises lots of questions. Are these residents going to Whistler? How many are day trips from Squamish vs. overnight trips from Vancouver? Did passengers of each vehicle spend a dollar while on the highway or did they spend $100? What does an extra 800,000 vehicles do to maintenance costs?
2015 Monthly Variations
For the next two graphs, we looked at 2015 data only. First, we wanted to know how traffic varies for a typical week in any month. Not unsurprisingly, we see traffic increase steadily throughout the summer, peaking in August with 96,000 cars per week. Thats more than 400,000 cars a month. Compare that to often-rainy November's 250,000 cars per month and you can think about how retail sales would ebb and flow. Your bottled water sales are probably down, but perhaps your hot tea and coffee sales are up?
2015 Daily Variations
Finally, we looked at daily counts. What are the average trends across a week? It looks like traffic picks up each weekend on Friday, dips a bit Saturday, and then peaks on Sunday as everyone rushes home to start the work week. Couple this with the above monthly flows - we know that an average of 16,600 cars passed on Sundays in August in 2015. Thats nearly 2.5 times the traffic on a Tuesday in November. Perhaps a great day for maintenance crews to do some road repairs?
Background on Investigation
We completed the above analysis with the help of BC's Traffic Data Program by looking at data from a traffic counter just north of Squamish at the location shown in the adjacent map.