The psychology of light rail safety

Courtesy of Andy Singer
Depending on context, the safety variables for light rail can be radically different.

If you’re a light rail operator, the final weeks of 2015 were probably disturbing. Within just a few weeks, there were three separate fatal crashes involving a train, ranging from a bicyclist to a wheelchair user to someone crossing a platform. Each one is a unique tragedy. 

The spate of fatal accidents remains something of a mystery, spanning both of the Twin Cities’ light rail lines, one of which has been operating continually for over a decade. After all, trains are as predictable as it gets in urban transportation. They’re large, loud and don’t swerve, they meet carefully designed safety standards, and they’re all driven by trained professional drivers. If the Twin Cities can’t keep our light rail systems safe, what hope is there for our chaotic car-choked streets?

Contrasting contexts of light rail

First of all, it’s important to note that a) a lot of time and thought goes into light rail station design and safety procedures, and b) depending on context, the safety variables for light rail can be radically different.

Also, would-be riders shouldn’t run across the street to “beat” or catch a train. It’s very dangerous. (I know this firsthand; while chasing the Green Line through downtown Minneapolis I caused my own bike accident.) It’s better to wait for the next train.

That said, the tragic fatalities of 2015 don’t really fit a pattern. The Green Line and Blue Lines are quite different from a safety perspective. The Green Line runs through the middle of University Avenue, a busy main street full of pedestrians, while the Blue Line runs alongside Highway 55 (aka Hiawatha Avenue), a semi-separated urban freeway.

“We start out designing crossings or station areas by working closely with the operations folks and designers who have experience in this arena, to develop as safe crossings as we can,” said Jim Alexander. He is the director of design and engineering for Metro Transit’s Southwest Light Rail, and formerly designed the Green Line stations. “We use the tools we have … signage to get people aware of LRT down the middle of the street, a combination of signals. And trains have bells or horns to use as well, to alert passengers and pedestrians crossing the street.”

Adding to the complexity is jurisdictional overlap. While Metro Transit controls the station areas and operations of vehicles, and budgets for things like gate arm crossings and flashing signs, the surrounding environments and streets are designed by other agencies. For example, the recent attempts to improve the crosswalks along busy Hiawatha (to prevent jaywalking) involved county, city and state agencies.

Courtesy of Sam Newberg
Crossing Hiawatha

“It’s quite an in-depth process in terms of trying to get all the stakeholders — internal and external — together,” Alexander told me. “We’re really trying to understand and get into the mind of the pedestrian, how they would want to cross the roadway and the tracks.”

Human-centered thinking

In urban design, there’s a lingering tension about how to deal with unpredictability. On one hand you have the law-and-order approach, which argues that clear rules, combined with enforcement and education, will encourage compliance and lead to safer streets.

On the other hand, there’s a more “human-centered” approach where design accommodates and “forgives” errant human behavior. Human-centered design (also called “user-centered design”) is where, as Wikipedia puts it, one tries to design around “how users can, want or need to use the product, rather than forcing users to change their behavior.” The idea cuts broadly across multiple fields, from software design to office ergonomics, but it gets really interesting when you start discussing city streets.

“The key is to design things intentionally that really channel attention and behavior through designing from a human-centered systems design perspective,” Kathleen Harder told me. Harder holds a Ph.D. in cognitive psychology, and directs the Center for Design in Health at the University of Minnesota.

Courtesy of Cameron Conway
The Washington Avenue transit mall is a case study for design details, where signage is almost always ignored.

From this perspective, the problem of light rail safety revolves around passengers having access to information because, as Harder says, people are very goal-oriented. When confronted with an approaching train, and the question of whether they will “make it” if they run across the road, people lose track of other pieces of the urban environment.

“If train riders are intent on reaching a goal, a light-rail or crossing-a-street objective, everything else pales in comparison,” Harder explained. “They will take riskier behaviors if they think not crossing the street will cause them to wait 20 minutes for a next train.”

One way to alleviate this risk might be to make “next train” information even more obvious. If you know you’ll only have to wait 10 instead of 20 minutes, you’re much more likely to be patient.

MinnPost photo by Bill Lindeke
One way to alleviate risk might be to make “next train” information more obvious.

Other important variables from a human-behavior perspective include: transit frequency (how long you have to wait for the next train), sightlines, barrier placement, signal timing (e.g. green lights, walk lights), signal priority (does the train stop at intersections), pavement markings and texture, signage and flashing lights, sounds (bells, whistles), sidewalk width and demarcation by street furniture, and the number of conflict points in the area.

Safety and the ‘cognitive load’

One key variable for street safety is the concept of the “cognitive load,” or the amount of attention that people are able to devote to processing their surrounding environment. Especially in an area of high complexity, like the corner of University and Snelling, home to one of the Green Line’s busiest stations, the amount of information can be overwhelming.

“What causes people to decide to cross or not depends on what cognitive zone they find themselves in,” Harder explained. “Are they distracted? Cognitively engaged in the environment? Or is their mind somewhere else attending to a piece of music? Where are they in terms of visual orientation? All these variables form a complex delicate balance.”

At Snelling, this might involve devoting more attention to sidewalk or street design, reducing the “decision points” and “actions” grabbing people’s attention. For example, currently the light rail does not have proper “signal priority” at key corners like this, and its halting progress through the intersection increases the uncertainty for drivers and transit riders alike. (Is it going to stop? How many extra seconds do I have to reach the train?)

“Some information isn’t presented in a cognitively digestible way,” Harder told me, speaking more generally about street design. “Some signs aren’t at appropriate heights, or what information they need, they don’t know, such as when the next train is coming. But if it is designed in such a way that attention is channeled, so that people can use the information readily, the probability of an error is reduced, because there aren’t so many variables in the fray.”

Signs vs. design

Another big lesson for urban design and safety is that there are diminishing returns to signage. For example, when Hennepin County attempted to make one lane of a downtown street into a “bus-bike-only” lane, no matter how many signs they installed, drivers didn’t follow the rules. There are stark limits to what signs can accomplish.

“Signs are not for people who know where they’re going,” Harder told me. “A sign isn’t going to grab your attention in an area where you really need to be captured. That’s why signs need to be designed in a very effective and judicious way.”

Harder recommends what she calls “deep design” instead of signage. The built environment should have easy cues that let people know when it changes. This can be done with architecture, street furniture, different types of pavement; for example, Harder points to the intersection of Church Street and Washington Avenue (on the Green Line at the University of Minnesota campus) as a place that needs more design detail, particularly on the ground where many eyes tend to fall.

“Different kinds of pavement, and even that has to be smartly,” Harder told me. “Deep design is not something you just splash on and say “we’re done.” You have to think about variables, the context, about the flow. You’ve got to be systematic and keep eye on the goal.”

A related design factor is the usefulness of educational campaigns: for example, fliers for university students, billboards or announcements for drivers or transit riders. But if you pay attention to human psychology, you find that design cues can easily trump a public-service announcement.

“People often say, ‘Why don’t we just teach people that they have to wait to cross the street,” Harder told me. “That’s all fine and good, but [a transit rider’s] goal is not to have to wait 20 minutes for the next train. Telling them to wait to cross the street is not going to percolate into the conscious awareness, because it’s more important to reach the train. It’s better to use design to give people the information they need.”

Solving the sticky and tragic problem of street safety isn’t easy, and with the increasing influence of distracting technology in our everyday lives (for drivers and pedestrians like), is only going to become more important. If 10 years of public-service announcements haven’t made light rail safe, what will?

Comments (26)

  1. Submitted by Mike Downing on 01/21/2016 - 11:16 am.

    Great article but…

    This is a great article but it appears to overlook the obvious question. Why aren’t LRT routes over or under I35W or I94? Access to stations would naturally be controlled and drivers would visibly see a viable alternative staring them in the face every day of commuting…

    LRT in MN appears to be a community redevelopment project so far rather than a real transit project.

    • Submitted by Adam Miller on 01/21/2016 - 02:09 pm.

      Because we want them to be useful

      Especially the Green Line would be substantially less useful if it served a freeway instead of the neighborhoods it’s in.

  2. Submitted by Isabel Levinson on 01/21/2016 - 11:37 am.

    Light rail safety

    I’m surprised there aren’t a lot of fatal accidents at the Hennepin Ave./Warehouse District station. Every day I see kids and allegedly grown-ups playfully (?) shoving each other onto the tracks, crossing the street on a red light, and coming very close to pushing passengers and bystanders onto the tracks. (I speak from experience on that one.) The other day a man dropped his hat on the tracks and ran back to get it, about five seconds before an east-bound Green Line train approached. Perhaps more transit police are needed at that station, handing out fines – or at least handing out a warning about living dangerously.

    • Submitted by Todd Hintz on 01/21/2016 - 12:21 pm.

      Police Force Presence

      I typically see two transit cop vehicles parked by the Hennepin station as I walk by on my way home. I haven’t spotted their drivers yet, but I assume they’re nearby and keeping an eye on activity at the station.

  3. Submitted by Ray Schoch on 01/21/2016 - 11:58 am.

    Something to be said

    …for both Mike Downing’s and Isabel Levinson’s comments. Cost is always an issue, and light rail is costly enough already that opponents to mass transit frequently invoke that metric in arguments against its expansion and use. A subway would be far more safe from the standpoint of traffic, but much, much more costly to construct and maintain. It’s a tradeoff. My own bias is that the LRT ought to have signal priority at virtually every intersection, with enough warning to give drivers and pedestrians alike plenty of time to decide on a course of action, but nonetheless giving the train the right of way, so to speak.

    Still a good article, and a nice, if cursory, explanation of some of the design principles that go into constructing this sort of public facility.

    Also, as Eric Black pointed out elsewhere in MinnPost today, people do not always behave rationally, and there’s no realistic way to totally prevent someone from doing something stupid that’s potentially fatal, or at least injury-causing.

  4. Submitted by Audrey Hamilton on 01/21/2016 - 12:19 pm.

    Pedestrians always come last

    I’m a frequent commuter by foot, bus and green line and I think it’s a shame there was no “deep design” for pedestrian safety before the green line was built. It seems to me that an effort to “understand and get in to the mind of the pedestrian, how they would want to cross the roadway and the tracks” should have been made before the fact. I can walk and chew gum at the same time, but I find that getting from the bus to the train is often tricky when I have to contend with speeding/turning cars, no median on University Ave. (have to cross the entire street in one go. What about disabled and elderly?), and having to wait through two stoplights before I can get from the bus stop to the train platform. When it’s cold, I don’t really want to wait 20 minutes, even 10, for the next train. Improved infrastructure for pedestrians is what we need in these towns, yet the focus now seems to be on infrastructure for bicycles. I wonder if any of these psychologists and other experts have spent a day as a pedestrian.

    • Submitted by Monica Millsap on 01/21/2016 - 12:53 pm.

      How true this sentiment is. I attended several neighborhood informational meetings before the light rail was built on Univ Ave. Many people who walk in the neighborhood and take the bus were there to speak up regarding how we wanted to cross, use transit, etc. We weren’t listened to then. Safety was a word tossed about, it was used to justify some of the designs- designs that had some agenda, but not safety. As the Snelling Univ intersection prepares to possibly host much more pedestrian, transit, and auto traffic in the near future, let’s hope some lessons have been learned and safety is actually a real consideration, not just a word.

  5. Submitted by Jim Million on 01/21/2016 - 01:55 pm.

    Burials by Bureaucracy?

    Bill makes good points about multi-jurisdictional faults, some that appear to result in cemetery vaults.

    Mike Downing is correct in viewing LRT as “community redevelopment project.” The Hiawatha Line was openly touted as such, promising to bring a generational renaissance to that blighted industrial corridor. The Green Line seems a better example of modern urban rail, connecting our separate downtown cores, various stadium locations, and truly enhancing commuter options while possibly spurring needed re-development.

    These lines should never have been built at grade, as many of us noted long ago. I’m pretty sure various planners considered the reality of pedestrian death. I also wonder what number was determined to be “acceptable”. This observer clearly wrote at the time: “either elevate it or bury it.”

    The ironic human cost of bureaucracy….

  6. Submitted by William Lindeke on 01/21/2016 - 03:08 pm.

    mid-block crossings

    One thing to note is that the “mid-block crossings” on the Green Line that everyone was really worried about actually haven’t been the problem. In my experience, they really signal to peds that you have to watch for cars, and also cars stop for people much of the time in my experience at least.

    To me the lesson is that the car safety problem and the LRT safety problem are related, somehow. I don’t really know what to do here, just wanted to open up the conversation beyond the usual victim blaming and educational campaign territory.

    • Submitted by Jim Million on 01/21/2016 - 10:28 pm.

      Thoughtful Article, Bill

      Bill, we should probably note that crossing University Ave., particularly in the Midway, has always been a sensory challenge: always many cars and trucks as long as I remember, bus blinds, etc.

      The LRT addition has made car/truck negotiations more difficult and distracting, putting peds at greater risk with little help from designers. Last week I encountered for the first time the median bump-out lane shifts that create left turn lanes. Those are a driver distraction hazard, for sure. Pity the poor walker who steps out into that confusion.

      As the avenue produces more residential and retail venues, pedestrian crossing will certainly increase; therefore, better crossing design is imperative. Don’t some of our cities have elevated sidewalks along the store fronts and crossing bridges above the traffic? Maybe that’s European design that would be handy here.

      We are now officially committed to these LRT corridors. The next one better be properly designed for all, or else all should resoundingly say “NO”.

  7. Submitted by John DeWitt on 01/21/2016 - 09:58 pm.

    Light rail stations with little/no car traffic

    When it was waging its war against light rail, the U of M painted an image of a Washington Avenue littered with the bodies of students struck down by light rail trains. To the best of my knowledge, there have been no incidents there.

    The Nicollet Mall station in downtown Minneapolis is one of the busiest and 5th street carries twice as many trains since the opening of the Green line. To the best of my knowledge, there have been no incidents there.

    In both situations, there is very little car traffic. Is it possible that people get so focused on avoiding heavy car traffic that watching out for trains falls off the radar screen?

    • Submitted by William Lindeke on 01/22/2016 - 11:04 am.

      exactly

      I think that’s very likely! Not sure if there’s data anywhere to back that up, though. In general, I think “doubling down” on transit is the way to go. Rather than having a street that tries to have good transit AND lots of car traffic with higher speeds, you have to choose one or the other. It’s almost impossible to do both.

      Regardless, here’s the FHWA report on the subject: http://onlinepubs.trb.org/onlinepubs/tcrp/tcrp_rpt_137.pdf

      • Submitted by Jim Million on 01/22/2016 - 11:41 am.

        Ibid.

        That’s the best argument for not building LRT on the street surface. Cars are absolutely not leaving our cities.

  8. Submitted by Ray J Wallin on 01/21/2016 - 11:12 pm.

    Layers and layers of…

    Boy, was this article eye-opening. It was like taking a train through a bureaucrat’s mind.

    I paraphrase:

    “We posted a bunch of signs, so we are off the hook.”
    “We have bells and whistles on the train.” So it is safer for pedestrians.

    Felt like I was reading a textbook.

    My favorite… “Make the next-train information even more obvious.” Hello. If you cannot see the next train coming down the tracks, the wait will be too long. Done. No signage needed.

    Yes, safety was taken into consideration, but from the train’s point of view, not the pedestrians. Wow, they put signs up. Like I can’t see the long shiny train tracks in front of me. Change the texture of the pavement? Sidewalk width and demarcation? Give me a break! Long shiny tracks? There, done. That is all you need to tell me a train may be coming.

    I am actually laughing while writing this, only because I have no other option. Have they not sat at the Snelling or Lexington and Univ intersections? People are walking every different way. That will not stop.

    In terms of active warnings for pedestrians? The very first time I heard the train horn, I knew the designers knew little of sound wave propagation and its frequency characteristics. Might as well not have a horn. The only reason I am writing is because I had a conversation about the green line just this weekend and we came up with no less than five cheap, simple ideas to make things safer for pedestrians. Our conversation was completely different than this article.

    I don’t hang out on the tracks, but I live a few blocks away and walk to a store or restaurant every once in a while. Each time I cross those long, shiny tracks, I look both ways and shake my head at the lack of ingenuity in the way pedestrians are incorporated into the design.

    Don’t get me wrong. I didn’t mean to go all Joe Soucheray on this subject. I love the design of the platforms and the train. Beautiful and functional. But in terms of interacting with the surrounding streets and crossings, I have to disagree with the author that a lot of thought was put into pedestrian safety features.

  9. Submitted by Dan Berg on 01/22/2016 - 11:50 am.

    Bad design because of bad initial parameters

    The design of the system is not good and any engineer on the project would have recognized it early on. A friend of mine who works for the Wisconsin DOT noticed it as the Blue line was being constructed. He quickly described the likely first victim as an older person who had lived in the neighborhood for a long time. Sure enough soon after the line opened that exact thing happened.

    The people designing the system are doing so within the parameters set by political thinking rather than any sort of meaningful intelligence or knowledge. Simply a bunch of special interests each hoping to bend the levers to suit their agenda whether it be sparking development in specific areas, reducing automotive use or simply putting in a train because they like it aesthetically or they did it someplace else. Not a recipe for a good design which is why the result is something that is, expensive to build, inefficient (cost of use above the value for the actual users), slow, dangerous (what is the deaths per passenger mile of light-rail compared to other options?), and doesn’t actually decrees traffic or increase mobility.

    Of course mixing modes in the same space will cause accidents, that is obvious. But a good design would have put the cost so far beyond any conceivable value that no advocate could have promoted the system with a straight face. But rather than admit the system isn’t worth it there was a push for it despite the problems it causes and the fact it does so at an astronomical cost. Light rail is nothing more than a fashion statement for pseudo environmentalists and politicians that understand that the general public is often fooled into thinking that any action is positive action.

    • Submitted by Dennis Tester on 01/26/2016 - 08:28 am.

      Amen brother

      “Light rail is nothing more than a fashion statement for pseudo environmentalists and politicians that understand that the general public is often fooled into thinking that any action is positive action.”

  10. Submitted by Jim Million on 01/25/2016 - 07:27 pm.

    Well said, Dan

    From the beginning our LRT push seemed to me more a “me, too” or perhaps a “we two” scheme.

    In final public comment session in Saint Paul City Council Chambers, I spoke as local resident (then) with knowledge from Roy Million, a TCRT minor officer and my long-deceased grandfather. Naturally, I’d been looking over our family shoulder at the old mobster schemes that killed street rail in favor of buses. So, when we all were getting “back on track” as it were, I closely followed the ensuing hearings and other promotional/planning rituals.

    At that Saint Paul meeting I calmly noted that one very real reason given at the time for streetcar removal was too many streetcar/auto collisions, especially in evening rush hour in both city centers. Those did tie up traffic for hours sometimes, but mostly in earlier decades when the auto was becoming king of the roads. Fortunately then, many “cars” ran behind each other, so workers wanting to get home were not greatly delayed waiting for another trolley. Not so with modern LRT/auto mishaps. Multiple agencies are brought to the scene and both auto commuters and rail riders are greatly inconvenienced by delay without proper expectations given.

    It was in that meeting that I looked directly at two official observers and first cautioned: “If you do build this, you must either elevate it or bury it.”

  11. Submitted by Edward Blaise on 01/26/2016 - 10:46 am.

    The final answer…

    Laugh as you will; but, giant, foam rubber cow catchers at the front of every train would scoop up the unaware off their feet and deposit them in a pool of balls or similar soft landing zone. Another million dollar idea cheerfully donated to the public domain.

  12. Submitted by Rachel Kahler on 01/26/2016 - 04:21 pm.

    Design

    There are a lot of flaws with the light rail design, for sure. If there was a lot of time and thought put into the integration of the LRT with the already existing landscape, the thinking was lacking creativity. I’m sure part of the problem was the need to get cooperation in design and planning between agencies. It is far from ideal to put cars and trains in the same space. But, if one must work with that foolishness, then you have to figure out how to at least simulate separating them.

    Also, you simply have to accept that some people are going to find away to terminate themselves despite your best efforts. Most people get only one chance to lose a contest with a train. One of the “victims” this December survived the first go ’round in a train-vs-cyclist match at the very same location. That he chose to make the same mistake (crossing in front of a train after bypassing the crossing arm) isn’t something you can design a prevention for.

  13. Submitted by Paul Udstrand on 01/27/2016 - 09:12 am.

    No pattern?

    See, this the problem with “Urban Designers”, the assumption that decisions by autonomous human actors are irrelevant or can be controlled by design. The common element in all of these fatal accidents is people either being distracted and not paying attention or making bad decisions (like trying to catch or beat a train on a bicycle). That’s not about design, it’s about pedestrians and cyclists making decisions on a scale that runs from: Perfectly Safe to: Fatal.

    The problem with all these design arguments is that they assume you can somehow eliminate the need for human judgement. Even in airplane cockpits which are one of the most engineered and designed environments ever in human history, as often as not accidents are the result of pilot error. The difference between a person who gets hit or killed by and the millions of people who never get hit by a train is that the people who got hit… put themselves in front of a moving train.

    I’m not saying that design is irrelevant, and certainly good designs are better than bad designs, but the idea that you can eliminate an individual’s responsibility for their own safety by designing perfectly safe environments is dangerous. Decades of experience with everything from nuclear power plants to computerized brake systems on cars have taught us that perfect safety ultimately relies human decisions. Any discussion that encourages people to assume that they’re environment is sooooo safe that they no longer have to look both ways before crossing a rail track or a street…. will get people killed. If you can cross it… you need to stop and look.

    • Submitted by Rachel Kahler on 01/27/2016 - 01:32 pm.

      Yup

      Exactly. You can’t control people and how they behave. And you can’t design away bad decisions, even if they’re fatal. We need to stop blaming the light rail and its design for EVERY death. What might be more effective is putting up signs that warn people that getting hit by a train will be considered stupidity on their part, not an accident.

      But, certainly, there ARE flaws. I’ll note that, while someone mentioned that there haven’t been fatalities at the Nicollet Station on 5th St., it is not easy to recognize where the rails are or where a car should be. That is, as a pedestrian, unless you’re pretty much staring at your feet and notice the rails before you’re standing on them, it’s not obvious where the tracks are. And, for your personal safety (aside from the train), you shouldn’t be walking around staring at your feet in Downtown. Further, trains don’t move like cars and they have a different profile than cars, so pedestrians who have been trained (haha!) to look both ways for cars may not recognize the train on an appropriately conscious level and/or the speed at which it is moving. Someone more creative than me could certainly design a way to get pedestrian attention where it should be.

      As for cars on 5th St., I believe that 5th should have been closed to car traffic, or at least the intersections designed such that a driver understands where their car should be. I don’t know how many times I’ve seen cars on that track, and it really isn’t a matter of a lack of observation on the drivers’ parts. 5th Street is one way going west(ish), yet the track takes up the entire right side of the street. That makes it very confusing to drivers who learned that you should turn onto the closest lane appropriate for your direction. If you’re turning right onto 5th, you have to cross over the track rather than hug the right curb. If you’re turning left, you have to turn left into the rightmost lane, which isn’t intuitive for drivers in countries where you drive on the right side of the road. Watch how people turn left onto one way streets sometime-they don’t turn into the rightmost lane by habit. What’s worse is that the intersecting streets are 2-way, which sets up a structural cue to pull half way through the intersection to turn left because you have to wait for oncoming traffic. What would have been smart is putting a curb-sized barrier that extends into the intersecting streets to guide cars to the appropriate part of the street.

  14. Submitted by Anthony Walsh on 01/27/2016 - 12:19 pm.

    That Design Thing

    The perceived flaws with the light rail design can only truly be flaws if they weren’t deliberately chosen.

    Otherwise, what you might call a flaw is a design trade-off. A trade off between features and benefits and costs. Sure, the designers could have hung the light rail over or under existing roads, but someone had to make the call that the expense was or was not worth the benefits.

    That call, that design decision had to take into consideration the cost of the materials to do it system wide, labor, traffic disruption, disruption to existing infrastructure like streets, water, sewer, power, construction schedules, the always underestimated time to create the design, lawsuits.

    Every feature chosen and not chosen had costs associated with it. Every feature chosen and not chosen had assumptions associated with it.

    At some point you can’t prevent someone from deliberately unsafe behavior, within which is included being unaware of your surroundings.

    It seems obvious that those complaining about flaws or problems would otherwise be complaining about the cost to implement the fix. It wasn’t free to do it at the design stage. Pick one!

  15. Submitted by Leon Hunter on 01/27/2016 - 05:23 pm.

    Light Rail Safety

    There should be overhead catwalks to the stations so pedestrians aren’t trying to cross the streets and rails during rush hour. And also scanners to verify all passengers have passes before boarding the light rail. There should also a conductor aboard to monitor passengers so the driver can focus on driving the light rail to avoid collisions.

  16. Submitted by Dan Berg on 01/27/2016 - 06:38 pm.

    Flaws…

    People make choices which are flawed every day. Very often the trade offs are evaluated and the design adapted to that choice. Flaws in designs are based on bad decisions on the value of the trade-off.

    The problem with light rail is that it doesn’t have any grounded goals. No way of measuring the value of the system so there is no way to evaluate the trade-off during the design process. What are the measurable outcomes and what are their dollar values? With that information a design team can actually have a shot and making decisions which are minimally flawed. Without it there isn’t much hope. Hard to make a choice on the value of safety when there is nothing to balance it against.

    The only parameters for light rail were political, which is likely worse than no parameters at all. Political parameters are always shifting and never attached to any anything measurable or based real evidence and always in conflict. No clear goals means no design focus and lots of flaws where success of failure is mostly random. Not as though actual success or failure mean much when the only evaluation is political.

    • Submitted by Paul Udstrand on 01/28/2016 - 09:53 am.

      Measuring value?

      “No way of measuring the value of the system so there is no way to evaluate the trade-off during the design process.”

      This is a mass transit system designed to move people. We measure its value by measuring how many people use it not whether or not people step in front of the trains once and while. That may sound cold but believe or not, the universe doesn’t revolve around your personal safety. During the design process you’re given a budget and a mission and you try to design the safest system you can within that budget. Is it really THAT unreasonable to expect that individuals will take some responsibility for their own safety and not step in front of moving trains? If people do step in front of moving trains, why is that a design flaw? Why is such an accident the designer’s responsibility instead of the individual who stepped in front of the moving train?

      Ultimately it looks like the “trade” is between building the most expensive systems or spending less and expecting people will take some responsibility for their own safety and not step, drive, or ride in front of moving trains. The fact is we have limited resources and we have to work with budgets. You can call that a political decision if you want, but it’s also about practicality.

      • Submitted by Dan Berg on 01/28/2016 - 05:52 pm.

        Not really

        Of course the world isn’t about any individuals personal safety, never made that claim. I agree that people in general need to be their own keeper and are responsible for their own safety. But the subject at hand is how with a large public investment do we evaluate a design to best weigh the various issues including safety. To suggest that the danger is the responsibility alone of those hurt is either disingenuous or it shows a belief that light rail is above scrutiny for some strange reason.

        Mass transit is designed ostensibly to move people but nothing is ever assigned any real value and that is the overarching problem that leads to flaws in design. If the measure of success for a transit system were simply moving a lot of people the Freeways in LA should be considered the most impressive system in the world. Of course the idea of not considering the costs along with the production would be ridiculous. One of the costs which must be considered is the value of the damage done by one system over another in accidents like those which seem common with our light rail system. In order to compare systems we must be able to evaluate them using the same units of measurement. Because light rail development is purely political there has never been any value assigned to the different goals. The only metric is “Can it get political approval”.

        The budget for light-rail wasn’t based on the value the system would provide. It was based on what political supporters were able to carve out of various budgets. So when the costs of various design trade-offs are reviewed they can’t be evaluated on what they do to change the value of the system. lWhen there is no desire by the supporters of the system to actual measure its value in concrete terms there is little chance the design won’t be riddled with flaws. Then again, since the system was built without the need for it to produce a positive end value relative to its costs it is hard to say there are any definable flaws. Other than the decision to build it in the first place.

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