Forty kilometre-per-hour residential speed limits are totally safe — unless you're young, old, or hit by anything other than the driver of a car.
On April 25, David Staples argued in a column (“City officials relying on flawed data in push for 30 km/h speed limit”) that a 40km/h residential speed limit is a reasonable compromise between the current limit of 50km/h and the position that many advocates are pushing for —30km/h.
In this column, Staples cited two research papers to bolster this argument*. He also cherry-picked his quotes to advance his position. As a result, I have a few criticisms of his logic and conclusion. Both, to borrow his term, are flawed.
Now, to be clear, I’m advocating for a residential speed-limit policy that protects the most people in most circumstances. And I also support the development of a multimodal transportation network that includes vehicles such as cars, vans and trucks.
This point, that advocates are not against cars, is being lost in the current debate.
But let’s get to it. Here’s what Staples got wrong: while he quoted a French study, he took the quote out of its context (isn’t avoiding that rule number one for journalists?) and thus changed its meaning.
Staples’ quote: “For speeds less than 40 km/h, because data representative of all crashes resulting in injury were used, the estimated risk of death was fairly low.”
This implies the risk of death would be low if Edmonton were to implement a 40km/h limit.
But, Staples omitted the line that follows: "However, although the curve seemed deceptively flat below 50 km/h, the risk of death in fact rose 2-fold between 30 and 40 km/h and 6-fold between 30 and 50 km/h."
This changes the meaning. Instead, this quote now indicates that the risk of death for a pedestrian is doubled between 30 and 40 km/h.
And for Staples’ credibility, it only gets worse.
The French study showed that, compared to the age group of 15- to 59-year olds, being older decreases your odds of surviving a collision with a vehicle. For those older and frailer, the study found fatality was significantly higher with speeds as low as 30km/h. For those between 60 and 74, however, the risk of death increases two-fold. For those over 75, there is a seven-fold increase. In addition, being struck by the driver of a van or other utility vehicles increases mortality risk, as does being struck by the driver of a truck — there, the risk increases by an astonishing 14 times.
The French study also found the risk of a pedestrian being killed is also greater at night, as well as when crossing outside of a marked crosswalk.
The French study Staples misused also goes on to put these statistics into a policy context. The authors indicate that those jurisdictions promoting walking and cycling (like Edmonton) might be increasing overall road traffic injuries unless appropriate strategies, such as speed management, are put into place. They suggest, among other things, “reducing vehicle speed, [and] separating pedestrians from other road users.”
The authors conclude by stating, "The present results confirm that when a pedestrian is struck by a car, impact speed is a major risk factor, thus providing a supplementary argument for strict speed limitation in areas where pedestrians are highly exposed."
A close reading of the paper that Staples cites to claim the city’s data is “flawed” actually provides ample evidence that it’s his conclusions that are. In fact, its authors argue for “strict speed limitation in areas where pedestrians are highly exposed.”
Still, why 30km/h instead of 40km/h? Why is one better than the other?
While an adult person might not be killed by the driver of a car going 40km/h, a younger or older person probably would be. For me, that’s not good enough.
I want the streets of my city to be safe for old and young people to walk and cycle. I want people to be safe from trucks and vans, too, and not just cars. And that demands that we define “strict speed limitations” on residential roads, where people walk and bike and exist in their neighbourhoods. That speed limitation should be 30km/h for residential roads.
I’m encouraged that Edmonton is moving in the right direction. Almost no one in Edmonton is advocating for the status quo.
Except City Council.
Columns that rely on sleight of hand and flawed methods to reach flawed conclusions certainly don’t help make our city safer.