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Originally Posted by xd_1771
Where I find conflict is when an LRT system is (as planned in Surrey) built on-street, even with dedicated lanes. From a certain perspective it would certainly seem like the safer choice. LRVs provide higher capacity than buses (LRVs stringed together provide much higher capacity on buses) - which means you can provide the same capacity with less transit vehicles and create less chance of conflicts. You'd think the accident rates per passenger km would be lower. The problem is, every proper statistical insight I've seen on this doesn't come to that conclusion. It doesn't even come down to whether it's running on mixed-use lanes or dedicated lanes or even separated rights-of-way - LRT systems are found to have significantly higher collisions per billion passenger kilometres.
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There is one thing that can be slanting the stats in one direction or the other: location.
LRT is more frequently located in larger, busier cities than not. Buses are everywhere. LRT also concentrates in downtown cores of large, busy cities with lots of street traffic and congestion and pedestrians. Buses are everywhere. Therefore all LRT is more often in close proximity to more cars and pedestrians than all buses.
Quote:
Originally Posted by xd_1771
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A huge percentage of LRT's billions of passenger miles are going to be located in close proximity to pedestrians in downtown cores and near stations where pedestrians gather to board trains.
Buses are everywhere so a smaller percentage of their billions of passenger miles are going to be away from concentrated groups of pedestrians.
Another interesting thing to point out, the spike in LRT deaths in 2004 coincides with Houston's opening in Jan 2004, and the second spike coincides with with the start of the 2007 financial meltdown when there would be a drop in total passenger miles traveled and probably a slight increase in suicides.
Hence why heavy rail ticked up too (people don't throw themselves in front of buses). And many LRT systems were hit hard by declining ridership during the crisis, so the effect would be exaggerated.
Quote:
Originally Posted by xd_1771
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This one stays pretty flat and are very close between LRT and heavy rail. And I actually find it odd how close they are.
Again, though, lol, there is a blip when Houston comes online and a general mellowing until the finical crisis takes hold and the number of riders drops.
But buses are way up there, probably due to when a buses is in an accident, many people on the bus can be hurt; while a train colliding with a car is less felt because of the mass of the train.
So, switching to LRT is a huge gain in safety in cutting the number of injuries. For the a huge savings in capital cost, there are similar rewards for the investment.
Quote:
Originally Posted by xd_1771
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This is like the first one. LRT just has a higher percentage of route km inside city cores than buses. They also tend to travel closer to high volume corridors (where more vehicles are) while buses tend to radiate out through neighborhoods (where fewer vehicles are).
Like think about it. What % of our bus fleet physically pass through downtown? Less than half. Every single Skytrain car enters the downtown core when in service. Every single CTrain passes through downtown, not many Calgary buses do. 100% of the LRT lines in places like Calgary, Portland, Houston, and more pass through downtown.
They are just going to be spending a higher percentage of their time in close contact with far more vehicles.
But again, we are talking about a difference of 2.5 collisions per million vehicle KM.
The other thing to note is this graph doesn't have any indication of severity. How many of these collisions with LRT are just fender benders that are dealt with in minutes? A train T-bones a car and totals it sending the system offline for hours, is 1 collision; a train rubbing the front corner of a car too close in a left turn lane at 1mph, is 1 collision.
Quote:
Originally Posted by xd_1771
Don't get me wrong, we're on the same side and you've made some great points, especially (and I will take note) on how the argument could/should be less centered on this. However, I think it's pretty clear that the intrinsic concept of having light rail trains run on streets is worse on safety compared to the equivalent BRT (or superior BRT + RRT) alternative, and that this is an issue worth moving along with the many others.
Think of why accidents on on-street LRT systems can happen in the first place. Trains are bigger, heavier, and take significantly longer to stop than a bus - LRVs in particular have to be even heavier (than non-LRVs) to actually survive any accidents, protect the people on the train itself and minimize damage and repair costs (as conveyed by the statistics you provided). When a pedestrian steps into the right-of-way at the wrong time or a car comes even a little too close, light rail trains can't always stop before it turns into a collision - and they can't attempt to steer clear either. They will come at you whether you like it or not. Accidents happen, and people do get delayed a lot.
Surrey is planning its LRT as a rapid transit replacement rather than a Prague-style downtown circulator. These aren't gonna be trams suited to downtown core speeds and pedestrians everywhere - they'll be attempting to offer rapid transit speeds on busy arterial roadways. If LRT does go ahead, we'll be in for some pretty spectacular and deadly incidents when they do happen.
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I think that assumption is wrong. The stats for buses quoted are for all buses, everyhwere. A huge number of these buses are going to have been running on quite suburban streets and in smaller towns all over the USA. That is going to affect the average. Like gun violence looks out of control if you look at just Surrey, but the statistics are more tempered when taken nationally.
Why would a bus, in a segregated system have fewer accidents than a train? most accidents happen because of vehicles making illegal turns or running lights. Buses are not somehow immune to other people doing that. People turn left infront of trains because they don't expect a train to come up behind them on their left (because normally no traffic does that). The same is true of buses in dedicated lanes with signal priority, I don't expect a bus to be coming up behind me on my left at a left turn bay.
And while a train T-boning a car is bad for the people in the car, the people on the train are relatively unscathed. A bus T-boning a car is still bad for the people in the car, but also bad for the people on the bus. So for the same number of accidents you could be increase the number of injuries (which is why I think that second graph is so high for buses).
And when you are using BRT, you would need more buses, more frequently to have the same capacity. More individual vehicles just increase the odds of an accident.
And I don't think stopping distance is as large an issue most of the time as you make it out. Most accidents happen right infront of the LRV. If the train is far enough away but still too far to stop, usually the car or person has time to get out of the way. Like I'm pretty sure a situation like a damsel in distress who is tied to the tracks and can't move, doesn't come up too often. So you really won't cut down on the number of accidents too much by having a better stopping distance.
So I think if you would still have a very similar accident rate regardless of if you went with BRT or LRT if they both had segregated lanes in the center of the road.
BRT might actually be worse because of the extra number of cars on the road due to lower ridership. After-all, the other side of the train-car collision equation is cars. The fewer cars on the road, the fewer things for the train to hit, the less likely an accident.
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