Skip to main content

A lowered speed limit sign is shown in a neighboorhood of Edmonton. This is part of the pilot reduced speed-limit zones that have taken place in six neighboorhoods.Jason Franson for The Globe and Mail.

Toronto's top doctor wants speed limits in Canada's largest city reduced by 10 to 20 kilometres an hour, an idea that'll be a tough sell when he pitches it to the Board of Health on Monday.

When Medical Officer of Health David McKeown revealed his proposal last week, it was panned faster than the speed of a car on one of Toronto's 60 km/h arterial roads.

Mayor Rob Ford dismissed it as "nuts, nuts, nuts, nuts," while the head of the public works committee urged Dr. McKeown to "stick to his knitting," unless he's after a job in the transportation department.

But Dr. McKeown's proposal isn't outrageous. Other major cities around the world are experimenting with lowering speed limits as part of their efforts to keep pedestrians, cyclists and drivers safe, something supporters hope will nudge urban dwellers out of their cars.

New York implemented its first "slow speed" 20-mph (about 32 km/h) zone in the heart of the Bronx last fall. Edmonton recently wrapped up a pilot project testing a 10 km/h reduction – to 40 km/h from 50 – in six neighbourhoods, three of which have elected to retain the lower speed caps. And Portsmouth, England, has received calls from across the globe about its decision to implement a nearly city-wide speed limit of 20 mph.

These interventions go beyond traditional traffic-calming measures, such as speed bumps.

"I'm not surprised that on first blush, some people might be concerned about the recommendation," Dr. McKeown said in an interview. "[But]the evidence of the relationship between speed and mortality and fatality is very strong."

Pedestrians are eight times more likely to die when hit by cars travelling 50 km/h than when struck by vehicles travelling 30 km/h, according to the World Health Organization.

Strong as it may be, the science supporting lower speed limits isn't exactly surprising. Slowing down saves lives.

However, municipal leaders must balance safety with the need to get from point A to point B in a reasonable time. That's why most of the cities testing lower speed limits are using neighbourhood streets, not arterial roads, as their petri dishes.

Take New York. In a bid to cut traffic fatalities in half by 2030, the Big Apple has implemented a raft of measures to persuade motorists to slow down, including cheeky commercials reminding New Yorkers there actually is a speed limit in the city, and it's 30 mph.

New York's Department of Transportation has taken a particularly aggressive step in the Claremont section of The Bronx.

Often abused as a shortcut, the quarter-mile residential neighbourhood saw 46 people killed or seriously injured in motor-vehicle crashes from 2006 to 2010, prompting the city to make Claremont its first 20-mph zone.

The zone is marked with 14 distinctive gateway entrances, 28 posted speed limit signs and nine speed humps.

"It sends a clear message to those drivers that neighbourhood streets are not shortcuts, they are not speedways," said New York Transportation commissioner Janette Sadik-Khan.

She said residents were "wildly supportive" of the new zone. "People were happy because they were tired of seeing their streets used as speedways."

Now more than 100 New York neighbourhoods have applied for slow-speed zones, she added.

"I think that you're starting to see cities all over the country look for these kinds of interventions. There's a big hue and cry to have safer streets," she said.

It's still an open question whether reducing the posted speed limit alone actually compels motorists to ease off the gas.

Claremont's experience is still too fresh to have produced useful data. In any case, the neighbourhood's slow zone includes speed bumps, making it difficult to separate their effects from those of a lower posted speed limit.

Edmonton, on the other hand, has the hard numbers to show that a reduced speed limit is little match for road design.

Beginning on May 1, 2010, the Alberta capital reduced speed limits in six very different neighbourhoods to 40 km/h from 50, using only signs and enforcement, including photo radar.

Overall, operating speeds fells by 7 per cent or about 3.5 km/h. The number of serious crashes dropped slightly in all but one of the test areas, where severe collisions actually increased.

Sounds promising, until you look at the actual speeds logged during the six-month experiment. In two older neighbourhoods, operating speeds fell to 51 km/h from about 53; in two grid-patterned areas, speeds dropped to 53 km/h from 55; and in two newly built pockets, speeds fell to 57 km/h from 60.

In other words, next to nobody respected the 40 km/h limit. Road design mattered. Motorists drove slower on older, narrow streets lined with parked cars, and faster on new, wider thoroughfares with little parking.

"One of the things about reducing the speed limit on any given road is that it needs to make sense to the public," said Scott McDonald, senior speed management co-ordinator for Edmonton's Office of Traffic Safety.

That's one of the reasons Dr. McKeown's recommendations have taken such a beating.

Right now, Toronto's speed limit, unless otherwise posted, is 50 km/h. Some wide arterial roads are 60 km/h, most residential streets are 40 km/h, and streets with speed bumps are 30 km/h.

The Medical Officer of Health favours reducing the residential limit to 30 km/h and the default speed limit to 40 km/h.

In a city strangled by gridlock, the thought of puttering along at 40 km/h on an arterial road isn't likely to be embraced. At least not by Toronto city council, which has the final say on speeds within city limits.

That doesn't discourage Dr. McKeown. Slower speeds are just a small – if controversial – part of the report he'll be championing on Monday.

"We are facing a significant burden of illness associated with obesity and diabetes and cardiovascular disease, and being more active in our day-to-day activities is a very important way of combatting those major health threats," Dr. McKeown said.

Lower speeds, higher savings

One English city has found that the slow way can also be the safe and cheap way.

There hasn't been a single fatality on the roads of Portsmouth since the island city of 207,000 on the south coast of England implemented a 20 mph (or 32 km/h) speed limit in 2007-2008. The cap applies to 1,245 streets, or 94 per cent of Portsmouth's roads.

Unlike most cities that try to slow down motorists, Portsmouth's limit isn't reinforced with speed bumps or other physical changes to the road.

"We decided to do it because we had a triple fatality on a residential road and, obviously, we had members of the public that were extremely concerned," said Adam Bunce, an assistant traffic engineer and project manager for Portsmouth's 20-mph project.

Reaction to lowering the speed limit by 10 mph was mixed at first.

Residents doubted that signs and the occasional police blitz would compel drivers to take their foot off the gas. (Drivers nabbed breaking the 20-mph rule are slapped with a £60 ($95) fine and three-point loss on their licences, unless they agree to attend a one-hour safety seminar, complete with videos of horrible car crashes.)

But a 2010 interim evaluation found the lower limits worked – for the most part.

Average speeds dropped by just 0.9 mph overall. On blocks where the average "before" speed was higher than 24 mph, the average speed fell by seven mph.

Total injuries for pedestrians, passengers and drivers, though, was down 22 per cent.

The biggest knock on the plan is that serious injuries actually increased by six per cent, a result Mr. Bunce dismissed as statistically insignificant because the city has so few auto accidents.

In other words, Portsmouth's motorists were already taking it slow.

The city's narrow residential streets, lined with Victorian homes and parked cars, aren't conducive to speeding. The 20-mph limit doesn't apply on the major motorways and distributor roads that carry most commuters.

Toronto and the majority of Canadian cities, especially those built out after the Second World War, don't enjoy the same advantages of urban form.

However, if any do decide to follow Portsmouth's lead, they'll find one advantage applies as much here as it does across the pond: A sweeping speed-limit reduction is cheaper than traditional traffic-calming measures.

Portsmouth was preparing to dole out £2-million ($3.2-million) over five years, mostly on speed bumps, when it switched gears to lowering the speed limit almost everywhere.

"Implementing a city-wide speed limit at £623,000 ($993,000), we saved ourselves £1.5-million ($2.4-million)," Mr. Bunce said.