Once the Eglinton West LRT opens, with likely the underground tunnelling and stations, the want-to-be-expressway that is currently Eglinton Avenue West in Etobicoke, SHOULD be changed to a more urban configuration. I think the city should change the intersections along Eglinton Avenue West at Royal York Road, Islington Avenue, Kipling Avenue, and Martin Grove Road to roundabout intersections.

 
For the kinds of volumes you see in those intersections, they would need to be turbo roundabouts. They are certainly safer for car traffic, but not really all that suitable for pedestrians and cyclists, which is why you see so many with grade separation for bikes in the Netherlands.
 
Once the Eglinton West LRT opens, with likely the underground tunnelling and stations, the want-to-be-expressway that is currently Eglinton Avenue West in Etobicoke, SHOULD be changed to a more urban configuration. I think the city should change the intersections along Eglinton Avenue West at Royal York Road, Islington Avenue, Kipling Avenue, and Martin Grove Road to roundabout intersections.

Roundabouts have a lower through capacity than traffic signals. With them, you might just create traffic congestion at the intersections without slowing the speed in between them.

The way many people drive, busy roundabouts will lead to multiple fender benders. At a traffic signal, rules are much more clear to everyone. Red means stop, green means go. How many even understand the lane they must be in when they are going to take the third exit from the roundabout vs the first exit?
 
Roundabouts have a lower through capacity than traffic signals. With them, you might just create traffic congestion at the intersections without slowing the speed in between them.

The way many people drive, busy roundabouts will lead to multiple fender benders. At a traffic signal, rules are much more clear to everyone. Red means stop, green means go. How many even understand the lane they must be in when they are going to take the third exit from the roundabout vs the first exit?
Turbo roundabouts can handle 4500 pcu/hr, which is comparable to pretty high throughput signalized intersections (though you can keep adding lanes to increase the throughput of signalized intersections). However, properly designed roundabouts and turbo roundabouts are empirically far safer, regardless of jurisdiction (they are demonstrated to work well in North America, too).

I would take low speed fender benders over this:


How many people understand that you have to be in the left lane to turn left, the right lane to turn right?
 
Roundabouts explicitly work with continuous flows. Traffic lights require platoons to work efficiently. So it is best not to mix them, or you get surges of traffic causing delays at roundabouts.
Since everyone has to slow down and possibly stop before entering the roundabout, I can foresee traffic being backed up from one roundabout to the next in rush hour unless the roundabout is 4 lanes wide. Eglinton is just too busy for a string of roundabouts. This is probably better suited for Rathburn, Burnhamthorpe or Royal York.

Truck and bus traffic don't work so well with multilane roundabouts. They need all lanes.
 
Could this article be used AGAINST going underground with the Eglinton West LRT? Probably not.

Study Discovers High Levels of Air Pollution on Boston’s Subway Platforms


From link.

Here’s one more good reason to wear a mask on the T: new scientific research has discovered unhealthy levels of air pollution on subway platforms in Boston and New York City.

During the summer of 2019, researchers from the NYU Grossman School of Medicine measured air samples in 71 stations during the morning and evening rush hours in Boston, New York City, Philadelphia, and Washington, D.C. Their findings were published on Wednesday in the journal Environmental Health Perspectives.

While New York’s subway stations had the dirtiest air, the study team found that the concentration of airborne pollutants on underground train platforms in Boston still reached levels that raise concerns for riders and for transit employees who spend long periods of their day underground.

The study team found that the average level of fine particulate pollution on Boston’s underground subway platforms was 139.8 micrograms per cubic meter – a level of pollution that’s categorized as “unhealthy” under the EPA’s air quality index.

Air quality measurements at above-ground stations, on the other hand, were found to be comparable to the ambient levels of air pollution on surrounding streets.

“Our findings add to evidence that subways expose millions of commuters and transit employees to air pollutants at levels known to pose serious health risks over time,” said the study’s lead author David Luglio, a doctoral student at NYU Grossman, in a press statement accompanying the research paper.

Among the MBTA stations that were analyzed, the study team found the dirtiest air samples on the Broadway station on the Red Line. More detailed analysis found that the primary source of pollution seems to be iron dust generated from train wheels and rails, as well as from wear and tear from trains’ collector shoes that brush against the third rail. Dust from decaying organic matter was another major component of underground pollution.

Notably, the study only measured air quality on the rapid transit network, not on commuter rail platforms, where diesel exhaust from trains could generate even higher levels of hazardous pollution.

The authors plan to do additional research into why some subway systems, like Philadelphia’s, are less polluted than others, and to recommend practices that could improve air quality in stations relatively quickly.

The MTBA is in the midst of a major project to upgrade ventilation and improve air quality at the Back Bay station, where passengers can often smell the exhaust from diesel commuter rail trains. Streetsblog has reached out to the agency to comment on this research; this story will be updated if and when they respond.
A reason to wear masks on any underground railway?
 
Apparently something similar was found on the London Tube platforms by some YouTubers with a PM2.5 detector. TfL apparently responded that subways use friction brakes which causes the high PM2.5, but that they were looking at using regenerative braking. Why had they not already done so! The maintenance savings alone are significant, never mind the health impacts. I would also expect rubber tire metro to be worse for PM2.5.
 
Apparently something similar was found on the London Tube platforms by some YouTubers with a PM2.5 detector. TfL apparently responded that subways use friction brakes which causes the high PM2.5, but that they were looking at using regenerative braking. Why had they not already done so! The maintenance savings alone are significant, never mind the health impacts. I would also expect rubber tire metro to be worse for PM2.5.
The Montreal Metro is actually better for brake dust because they use wood brakes.

 
The Montreal Metro is actually better for brake dust because they use wood brakes.

The worse PM 2.5 is from tire particles.

It's actually a real problem. A lot of PM2.5 will remain in cities even after EVs are adopted just from tire wear. It's just that currently, diesel engines, car exhaust and brake dust swamp the contributions from tire wear.
 
The worse PM 2.5 is from tire particles.

It's actually a real problem. A lot of PM2.5 will remain in cities even after EVs are adopted just from tire wear. It's just that currently, diesel engines, car exhaust and brake dust swamp the contributions from tire wear.

According to this study, Montreal scored lower than Toronto in PM 2.5


Overall, PM2.5 levels were found to be highest in the Toronto metro, a system that is largely below-grade and using a traditional steel wheel-steel rail rolling stock design. Steel wheel-steel rail metro design has been noted to generate PM “rail dust”.(5, 19-23) This environment is also subject to the regular resuspension of particles due to the piston effect of train movement. The piston effect has been suggested by the examination of temporal variability in metro PM levels which coincide with a sharp rise in wind speed/turbulence and the motion of a train.(21, 24) Montreal is also a below-grade system, but the much lower sampled PM2.5 levels may be due to the use of rubber wheels and concrete rollways compared to a conventional steel wheel-steel rail design. 21% of daily PM2.5 exposure in Toronto, 11% in Montreal, and 12% in Vancouver.
 

Back
Top