Hi, My name is Prospector, and my job is to make those restaurant drive-thru lines not affect your morning commute.
I work for a municipality, and look at every new build from a traffic perspective. WE have a few tools up our sleeves to try to control the mess made by traffic from new developments, and just because I really don't want to work on the report sitting in front of me, I'll write about what I'm supposed to be doing here instead.
1. Preconsultation - Joey Marconi comes into the planning department to let them know he's thinking about building a new 'insert business here'. He requests a meeting with the planning staff to go over what his lot allows and what rules he will have to follow.
2. Circulation - Based on what came out of the pre-con, Joey hires a bunch of professionals to do work in support of his development. He may need an archaeologist to see if he is disturbing a significant site, he may need an arborist to do a tree inventory, he may need an architect to tweak corporate (franchise) designs to meet local bylaws, he may need a geologist to look at soils and slopes, he may need a traffic engineer to look at his site traffic. All these reports are sent back to the planning department. The traffic report gets sent to me.
3. Traffic Impact Study (TIS) Review. - in the traffic report a site plan is provided which shows the intended internal circulation. There is also an analysis of traffic on the adjacent road, and analysis of what the traffic will look like with his new business opened, and an analysis of what that will look like in 5 -10 years as other land around him develops. Some bylaws will limit what he can do - these include building shape and size, parking requirements, drive-thru stacks, driveway design (*apron width and curb radius), Building code will dictate location and size of fire routes in the site. I review all this to be sure that the bylaws have all been met. Once I'm satisfied with that, I turn to the traffic analysis.
4. Traffic analysis. There is a big book of lookup tables that guess based on industry averages how many trips per square foot different businesses will generate during rush hour. The challenge with this is that the numbers are based on a limited data set and don't always reflect local conditions. For instance, Tim Horton's in Canada performs very differently than Second Cup (another coffee shop in Canada), and the tables are mostly developed based on coffee shops in the USA. SO traffic is estimated based on these tables that may not be the best indicator. If the traffic dude reviewing the TIS is new or unsure of himself, it is easy to just accept the industry standard, but if they are more experienced, they will kick back the study and ask that the analysis be repeated using a proxy site - in other words, take the traffic generated by another Tim Hortons and use that trip rate rather than what is in the manual.
Once the number of cars entering is determined, we look at the direction everyone will come from. Based on the marketing plan for the business, we will get a good feel for the catchment area. Overlaying that on existing travel patterns, or on anticipated origin-destination patterns, we can make a pretty good guess of where the cars are coming from to get to the business. We use simple ratios to overlay the new projected traffic into the existing travel pattern, and voila - how many cars are making left, right, or through moves at each intersection along the way. From this we can analyse intersection operations to see if a new signal is needed, or new lanes, etc.
If we find that the site driveway cannot hold the number of cars needed, we will kick back the report and suggest the developer find a way to add accesses (through adjacent properties? A back way in?) or make the site more appealing to other modes than the common clown car (bike racks, bike lanes, transit bays, walkability, transit incentives, etc.)
Eventually the developer either finds that the site is too onerous to meet our demands and moves to another site that will work, or they make concessions in order to get the site to work. Both of these solutions make me a very unpopular guy to most developers.
Now about Tim-Horton's specifically... They are a really good corporate citizen. Their sites are really bad. They got to be known for having 'the Tim's factor' at adjacent intersections, and the heat was on with an ever-increasing traffic and collision problem at their driveways. In response to this, about 2 years ago they started converting all sites to a dual-drivethru setup which cuts service time in half, and results in a queue length reduction of about 60%. Despite this, they continue to meet our bylaws for long storage lengths without challenging the bylaw. This gives me a lot of comfort when they apply for new sites.
http://www.macleans.ca/economy/business/double-double-lanes/My biggest issues with drive-thrus are that they contribute to the 'car-minded-ness' of our society. We build cities for cars, when we should be building cities for people. None of those site bylaws would apply if you built your site for people, rather than cars. My second issue is with safety of the driver. Your primal mind is wired to rescue your food before anything else, and driver distraction with food in hand, or in car is massive. About a year ago I sat and filmed drivers receiving their food at a drive-thru. Over 90% drove away before puttin gaway their change or their food. That means they are fumbling with change and food at 50 km/h rather than while sitting still in the drive-thru. Scary, especially if there happens to be a guy on a bike riding across the driveway when they pull onto the road. I've been lobbying for a 'safe-spot' for drivers to pull off into and put everything away for a while now, but getting no-where.
Some other sites (ie. Costco Gas Bars) fight against any local improvements in response to safety and congestion, and I can only point them to reports and collision stats in order to transfer liability from the city/region to them.
But enough about me. Lets get back to delicious coffee (with 2 sugar please).