Here are some miscellaneous questions and answers from my interview with SDOT Senior Engineer Darlene Pahlman. For the most part, these words are paraphrases. See also Part I of this report.
What can operators do to improve their practices? SDOT has transmitted to Metro’s training staff the accumulated best practices. If operators would like SDOT to come provide another training seminar they’d be happy to do so; please coordinate this through your training focal.
Is manual control of the signals possible? “We can remotely access the controller and can issue manual commands.”
What is the minimum achievable headway is on MLK? “We think we can successfully operate a system at 5 minute headways.”
What is the signal cycle length on MLK? 2 minutes, although there’s no firm bound on how long a car might wait.
Is there a special operating mode at late night or on Sundays? At these times we “run free”, meaning we try to grant demands to cross the tracks as they arise.
Are there any plans to expand the “running free” period? Not unless the data shows us a problem.
Is there any threshold of poor traffic flow where trains lose signal priority? That is no city policy at this time.
Would SDOT consider opening their controller configuration? No, for security reasons.
How are the pedestrian crossings working? At first, we had a lot of complaints about inability to cross MLK on a single signal. We installed the “countdown” signals and those complaints dropped precipitously.
yeah. opening the controller configuration in this age of hackers would be a BAD idea.
Meanwhile any group with some neon vests, and perhaps white gloves, could easily shut down the intersection and or direct traffic through it.
“Security” my ass.
I don’t think that’s valid, honestly (Gordon). I think that if the city wants to use “security” as a reason, they need to provide a threat model analysis first.
The two minute signal cycle also applies to pedestrians of course. The Walk light will appear only once every two minutes (assuming someone pushes the button) but then stays on only five seconds, then the countdown begins.
Result is a pedestrian can lawfully begin crossing MLK only during that five-second window, the one that can appear only once every two minutes. To be able to cross the street only for five seconds out of every 120 is not pedestrian-friendly. Imagine if motorists got only five seconds of green time out of every 120 seconds.
Gotta find a better way here folks.
Has anyone had bad experiences of missing train or bus connections due to the crosslight timing?
I’ve missed a train at Othello because I wasn’t able to get across MLK. The traffic was just heavy enough that I didn’t feel safe jaywalking (which is unfortunately what I usually do at the surface stations along MLK).
I have had that experience at the Columbia City station. It looked as if I had plenty of time to get to the train, but because I had just missed the crosswalk signal, I got to watch the train go right past me while I waited to cross MLK. In low-traffic periods I just jaywalk it — visibility is good there and it feels very safe to do so. But this was a high-traffic period so I could not do that.
It is definitely frustrating when you are thinking “Oh, there’s the train, but I’m so close I have plenty of time to get across and catch it” and then the light just never seems to change and the train passes you by.
My advice: hold up your hand and stop the cars. It’s worked for me.
That’s what I do as well. A tire iron helps too.
Baseball bats and bricks work if you don’t have a tire iron handy. ;-)
Are you talking about stopping cars that have a green light so you can cross on red?
Ha – like I’d wait! I would have missed a lot of trains were I not such a prolific jaywalker. I can’t even remember the last time I crossed with the signal at Columbia City, and even getting from the Starbucks on Rainier and MLK to Mount Baker Station is a jaywalking favorite of mine.
Unrelated to MLK, but I witnessed an elderly woman struggling to cross Denny Way in one crosslight at Melrose this morning.
Bold woman. That part of Denny is the opposite of pedestrian friendly…
I once missed a NB train from Columbia City station because I couldn’t get across those two northbound lanes of MLK from S Edmunds St. By the time I crossed, tapped my ORCA, and sat down, it was only two more minutes until the next train came, so it didn’t bother me much at all.
Sometimes I’ll cross two lanes of MLK against the signal if there’s a large break in the traffic. Having the station in the center of the roadway makes it a convenient safe spot for pedestrians crossing against the light, or entering the crosswalk after the countdown has begun.
The pedestrian signals should preempt everything except Link and emergency vehicles.
Agreed!
… and, isn’t it possible for a pedestrian phase to be skipped once, meaning a pedestrian may have to wait for up to 4 minutes?
Yes, that’s what Ms. Pahlman, P.E., says. Sigh….
When they install countdown signals, they often reduce the overflow time drastically also. I’ve seen several 30-second blinking-red signals replaced by 10-second countdown signals. That does keep people from crossing on blinking-red if they only have 10 seconds instead of 25. But it doesn’t necessarily give enough time for an elderly person or somebody rolling a cart to get across the street between green and red.
The other wacky thing about those countdowns is that they’re the time you get to cross the whole street – but if you’re going to a Link station, can you lawfully enter the crosswalk when, say, half the time has elapsed? Dang, I should’ve thought of that question earlier!
The Columbia City station definitely seems to take forever (more than 2 minutes, I swear) to get a crosswalk light. I think part of the problem is that the crosswalk only applies to the entire east-west crossing: 2 lanes northbound, the light rail tracks, and 2 lanes southbound. If they could have a crosswalk light on the island (maybe one in the middle that has lights for eastbound and westbound foot traffic, or one on each side of the island) they could maybe allow people to cross more often.
I noticed this. There should be an intermediate light in the middle.
The pedestrian signals are the most frustrating aspect of my daily ride to work. I usually cross MLK at S. Kenyon St. Since the sensor in the road doesn’t usually detect my bike (another problem), I hit the Ped signal and wait. Oftentimes, a car is waiting and when the light turns green, the walk signal is still red. That’s when I revert back to riding like traffic and cross with the cars.
Based on what I see at Kenyon, I’d say that Ped signals are certainly skipped. I doubt anyone waits the whole 4 minutes to cross, since any reasonable person would give up and jaywalk at that point.
I used to be very cautious when crossing MLK, but with the increasing frustration of waiting legally and feeling like a sucker, I have been jaywalking more and more. If Ped crossings of MLK were easier, I’d guess that jaywalking would go down.
Assuming your positioning is good, if you’re not triggering the loop detectors, drop SDOT a line about it; they might not be properly set to detect bikes. You might even suggest they put in some markings to indicate where bikes should position themselves to trigger the loops. (Of course, if you’re riding some carbon fiber number, you might just be SOL.)
Ditto. At least with the City of Kent, they had a problem fixed for me within a week. They just went out and adjusted the sensitivity. I still occasionally have problems, but not something laying my bike down for a couple seconds doesn’t fix.
Does it have one of those T markers that McGinn showed to Streetfilms?
http://www.streetfilms.org/tag/seattle/
Those markers were news to me.
…and they never work for me, and my bike is steel!
Nope. There’s no fancy markings anywhere I’ve been in the Rainier Valley. I’ll have to check if I see loops either on the East side of Kenyon. Maybe they’re buried in the concrete?
FWIW, if you can’t see the cuts, assuming there are loops and they’re in the standard location, positioning yourself in the middle of the lane, either a foot before or after the stop line, should put a wheel smack over the sensor. It can also help to lay your bike down for a second over the sensor, as the loop created by a metal rim will apparently trigger the sensor better than anything else. Or, you know, just run the red when it’s safe :)
The T marking is nonstandard, and in some places around town you’ll find the more appropriate marking. Of course, even the proper markings are not all that intuitive, which is why there’s accompanying signage (R10-22: “To request green wait on [image of pavement marking]”). But apparently SDOT doesn’t think we need to bother with that, go figure.
They’re wrong, we do.
Agreed, Ben.
Why are Link trains given any priority at all at major intersections along MLK Jr Way? Here is an article from the Times which mentions this topic:
http://seattletimes.nwsource.com/html/localnews/2009414485_stothello03m.html
A quoter from this article:
“Drivers wait longer at traffic lights because trains take priority. (Some 22,000 cars a day approach the Othello/MLK intersection from west and east.) On a recent Friday morning, a driver screamed as he gave the middle-finger salute to a passing Link train.”
At S. Othello St. about half the total boardings of Link trains are on the trains. In other words, if there were 16,000 boardings per day in January, about 8,000 people per day rode Link trains across S. Othello St. per day, both directions combined.
Lindblom wrote that 22,000 vehicles per day approach this intersction from the east and west. At the national average of 1.57 people per car, that would be about 35,000 people per day going east and west at that intersection. More thousands of vehicles per day turn left from MLK Way at that intersection, and they, also are forced to wait for Link trains. Then there are likely thousands more pedestrians and bicyclists per day who are forced to wait at that intersection for Link trains.
What is the rationale for giving about 8,000 people per day riding Link trains across S. Othello S. priority over the 40,000 or so drivers, pedestrians, and bicyclists per day who want to cross MLK Way on S. Othello, or turn left off of MLK Way? How is this justified?
I think that Link trains should get zero priority at the S. Othello St. intersection and all other major intersectsion along MLK Jr. Way. Traffic on MLK Way should already be getting some priority with longer green lights than cross traffic gets.
The lights on MLK Jr Way should be synchronized for 35 mph in the peak direction, and Link trains should have to just go with that. This would mean that Link trains in the peak direction should hit every green light except the first light after they stop at a station. Since there are only four stations along MLK Jr Way (counting Mt Baker), this should not be that big a deal to Link trains, and it would be a great help to the many times more people who are now delayed by Link trains at intersections.
It doesn’t look like Martin asked my question about the Interlocal Agreement between ST and SDOT about “What’s to keep a rogue Mayor from directing Public Works to cancel signal priority, or change the rules?”
If Norman is elected, how are Link’s 5 minute headways protected?
I did, but there wasn’t a neat way to phrase it. The City owns the signals, so the buck ultimately stops there. However, in practice, they do this stuff in conjunction by negotiating with ST and Metro.
Well, we’ll just have to keep Norman from being elected. It’s a little too late for that in Bellevue. Thanks for asking Martin.
Yes, Norman, heaven forbid that even one street in Seattle should actually give priority to rapid transit. Automobiles should rule everywhere! And of course we know that ALL of those 35,000 people are subjected to unreasonable delays due to Link; none of them ever move smoothly through the intersection in a minute or less on the first green they see (like I manage to do most of the time).
And how wise you are to count up the users just for today, because we all know that what happens today is what’s going to happen for the next 100 years. Yeah, right.
And we all know that if Link trains were not given signal priority that they would never hit a green light at S. Othello St. — they would always hit a red light there? No Link train would ever move smoothly through the intersection in a minute or less on the first green they see?
I guess it’s really wise to set traffic signals on some projected ridership 100 years from now, and not on what is actually happening today? Because those traffic signals can never be adjusted in future years if ridership numbers change over the years? Yeah, right.
Norman, what’s your logic for not dividing the non-Link person count by half when you do that for Link? Lindblom didn’t cite his sources for the 22,000 figure and that article didn’t seem to indicate that he ever talked to people at the city. (I’m speaking as a citizen here, not a city employee)
And reposting some of what I said earlier:
The city has traffic volume maps on their website (though they’re outdated). Even with 2006 data, MLK carries far more people than any other cross street.
Why would I divide the number of people approaching MLK on S. Othello St. by anything? This question makes no sense.
I am not talking about traffic on MLK. I am talking about the number of people on LINK trains as the trains cross S. Othello St. I thought I made that clear.
The link you give here shows only traffic volumes around downtown. I don’t see the MLK/S. Othello St. intersection there. Can you tell me how to see traffic volumes at the MLK/S. Othello St. intersection? If not, I will use Lindblom’s figures. I doubt he just made that up, but I don’t know where he got that figure. And I don’t see any numbers for that intersection in the Link you posted.
Hint: Click No. 3. The thickness of the lines indicate the volume. Average Annual Daily Traffic for Othello is 9,400, MLK is 15,200. Since Link runs along MLK, traffic on MLK benefits from it. Ignoring it otherwise is an unfair comparison. As for turning movements, without specific counts and delay data collected you really can’t make number-based claims. “1,000’s” of turning vehicles is just a SWAG. “and they, also are forced to wait for Link trains.” is just an assertion that they wouldn’t be delay had Link not been there which I doubt. Streets like MLK with signal coordination will negatively impact cross street traffic, with or without Link, since priority is given to that street.
“Why would I divide the number of people approaching MLK on S. Othello St. by anything?”
Here are your words:
“if there were 16,000 boardings per day in January, about 8,000 people per day rode Link trains across S. Othello St. per day, both directions combined.”
Somehow each Link boarding is worth half a person even though the same assumption could be applied to vehicles and pedestrians. How do you know ALL of them are unique and therefore not be divided in half like you did for Link?
Oran, I used the orginal pdf link for that map, and enlarged it to 200% so I could actually read street names, and now I do see that S. Othello says 9,400 vehicles per day. I could not make out street names from the link you gave. So, I wonder where Lindblom got 22,000. I am not assuming either figure is right or wrong, but would like to know why Lindblom uses 22,000.
Left-turning vehicles using MLK absolutely are delayed by Link trains. You must cross Link tracks when making a left turn off of MLK, so, obviously, if there is a train crossing when you were supposed to get a green for a left-hand turn, you don’t get that green light because the Link train is in the intersection.
As for dividing the number of Link boardings by half. What are you talking about? I am talking about the number of people who are actually on Link trains when those trains cross S. Othello St. Has nothing to do with counting each Link passenger as only “half a person.” I count each Link passenger as one person.
If 10 people get on a Link car in the downtown tunnel heading south, and 1 gets off at SODO, 2 get off at Beacon Hill, and 2 get off at Mt. Baker, how many are left on that Link car when it crosses S. Othello (f there were no boardings at any station south of downtown)? Are there still 10 people on that Link car? Or, are there only 5?
I am counting all the people who are actually on Link trains as they cross S. Othello St. People who get off trains before they reach S. Othello, or get on trains after they cross S. Othello, don’t cross S. Othello St., now do they? So, they don’t count as boardings who cross S. Othello St.
Do you honestly not get this? You don’t realize that not every person who boards a Link train rides it all the way down MLK? Have you ever taken a trip on Link that did not cross S. Othello St.?
Priority doesn’t mean all cars have to stop when a train passes. It’s not a freight train criss-crossing everything. The north/south MLK lanes (those parallel to the tracks) are turned green and cars can flow freely. And the system is smart enough to adjust a few seconds here and there for the best traffic flow.
And if trains aren’t given priority, shaving off a valuable minute or two or three from an otherwise miserably slow ride, that 8,000 number will never be able to grow to 35,000.
A “vaulable minute or two”. And the minute or two (or three or four) that tens of thousands of drivers and pedestrians have to wait for Link trains is not “valuable” to them?
Or drivers and pedestrians are just “less valuable” people than Link riders?
MLK already gets priority over cross streets, by getting longer green lights than cross streets. That should be good enough for Link trains, also. As long as Link trains keep up a steady 35 mph on MLK they will hit a green light at each intersection, in the peak direction, without any special signal priority.
A 2-car Link train is typically carrying 50, 100, up to 200 people. Its size is equivalent to about 8 cars, which typically carry 8 or 10 people among them. Maybe one car will have six people in it, but certainly not all eight cars. So giving Link signal priority benefits many times more people than it detriments.
ST claims ridership in January was 16,000 per weekday. There are 250 trains per day, so that averages to 64 BOARDINGS per train per weekday. The averate trip length on light rail is about 4 or 5 miles. Since Central Link is about 15.7 miles, that would mean that the average trip is about 1/3 of the full route. So about 1/3 of total boardings are on a Link train at any given point along the route. That would mean about 21 passengers on a 2-car Link train at any given point throughout the day.
At any given time, a Link train will have more people on it than are waiting in cars at those intersections. Following the logic of Spock in Star Trek II, the train should take priority (“The needs of the many outweigh the needs of the few”)
Eyeballing your numbers above it’s obvious that you are cherry picking again. (Seriously, why do you keep doing this? It only serves to undermine your arguments) Frankly, I’m tired of picking through them other than to say that Link ridership was over 14,000 per weekday in November, not 8000 as you assert. (And that’s before the 194 went away so I imagine that number is higher now)
Yes, the trains take priority, but when a train rolls through with 50, 100, or more people on it, that’s the equivalent of a LOT of cars. Spock’s logic still holds.
velo: stop accusing me of cherry picking. I wrote that in January, Link averaged about 16,000 BOARDINGS per day. At least half of those riders never made it to Othello St. — they either rode only between stations north of Othello, or between stations south of Othello. There are many people who ride Link only between Mt. Baker and downtown, or Beacon Hill and downtown, for example, and never make it to Othello.
It is actually probably significantly less than 50% of all boardings who cross S. Othello street per weekday on Link, so I am giving Link the benefit of the doubt with the 8,000 per weekday number at Othello. It is probably closer to 40%, if not 1 out of 3.
There are not necessarily more people on any Link train than there are people held up by each Link train. Also, because the Link trains cause cross traffic to back up significantly, some vehicles (and even pedestrians, as mentioned in this thread) have to wait more than one red light to cross MLK Jr Way. When that happens, there are many vehicles backed up and waiting on S. Othello St. because of Link.
The logic should dictate that MLK gets longer green lights than cross streets, if there are more people using MLK Jr Way than cross streets. There is no logic that says that a Link train should always get a green light every time it nears an intersection, unless it is traveling at the 35 mph the lights are synchronized to. That synchronization should not be screwed up by Link trains, as is currently being done.
Yes, b/c only those people actually on that train at the time are affected by erratic service. As soon as one is out of the danger zone, the trains automatically beam back to their regularly scheduled position.
Thats the practical rationale.
If you want the philosophical, b/c Seattle has decided to start valuing transit riders (and their time) above car drivers.
How are the people who ride Link between Beacon Hill and downtown, or Mt Baker and downtown, or between two stations inside the tunnel, or between SeaTac and Tukwila, or between Tuwkila and Rainier Beach, or between SeaTac and Rainier Beach, etc. etc. affected by Link trains hitting a red light at S. Othello St.?
“Seattle has decided to start valuing transit riders (and their time) above car drivers.”
Maybe you have, but “Seattle” has not. The vast majority of all trips in Seattle are still taken by motor vehicle. Remember, buses use streets, also. So has “Seattle” started valuing Link riders (and their time) above bus riders (and their time)?
Moreover, why are transit riders, and their time, more important than drivers, and their time? You have any rationale for this? Transit riders are already being extremely highly taxpayer subsidized. What makes transit riders superior to drivers, pedestrians, and bike riders? Are the kids going home from Franklin High on Link superior to someone trying to get to work in their car?
“How are the people who ride Link between Beacon Hill and downtown, … or between two stations inside the tunnel. affected by Link trains hitting a red light at S. Othello St.?”
The late train thows the schedule out of whack. Have you never waited for a bus that was 20 minutes late, or came at the same time as the following bus?
Mike already answered the practical half, as to the phisophical:
B/c encouraging transit ridership (and rail in particular) is a large part of the solution to many of Seattle problems. It reduces greenhouse gas emissions, reduces sprawl, encourages livable communities, reduces congestion, enhances social cohesion, and has a host of other positive externalities compared to SOV users.
If you ride a Link train from Westlake to Beacon Hill, or Mt. Baker, how does a red light at Othello affect your schedule?
Or, if you ride from SeaTac to Rainier Beach, how does a red light at Othello affect your schedule?
Having to stop at a couple of red lights on MLK each trip would cost Link riders only a couple of minutes, at most. So what?
All the stuff Anc mentions is nothing but opinion. “Enhances social cohesion”? lol
It effects you when the train you are waiting on is late b/c it was caught in traffic. Amplify this out over the course of a day and you a completely jacked up schedule.
As to opinion, maybe, but it is the opinion held by a good chunk/majority of Seattleites and their elected representatives. Doesn’t matter if it is true or not (and it is btw ;)) that is the rational behind why transit ridership is pushed over SOV ridership as evidenced by giving them priority. Which answers your question.
Norman, by the same logic, we would suggest that because freeways have more people on them than small roads, we should spend all of our money on freeways.
A big part of the point here is to make transit ridership GROW. We do that by making transit reliable – and in a year or two (and can you really not think farther ahead than tomorrow?) there will be more people on the train than in cars.
Even if there isn’t, the modes that have the highest capacity should have priority– and that’s Link.
Your comments are not logical, at all. Freeways, by definition, are grade-separated from cross roads (overpasses and underpasses). Not comparable at all to Link down MLK Jr Way.
“A freeway is a type of road designed for safer high-speed operation of motor vehicles through the elimination of at-grade intersections. This is accomplished by preventing access to and from adjacent properties and eliminating all cross traffic through the use of grade separations and interchanges; railroad crossings are also removed.”
Also, who said anything about money in this thread?
In a year or two there will be more people on Link at S. Othello than in cars? Where do you get that? Even by 2030, I believe the projection is for only about 45,000 boardings per day on Central Link. That would mean no more than around 20,000 per day riding Link trains past S. Othello St. in 2030.
That is still a lot less than the 40,000 or so people who want to cross MLK Jr Way right now at S. Othello St., in motor vehicles, on foot or on bicycles, plus those who are on MLK Jr Way and want to make a left-hand turn onto Othello, and have to wait for Link trains.
I often get accused of skewing my numbers on this site (see Velo’s post above), but where do you possibly get numbers to back up your contention here?
Gosh… if only Sound Transit had put that line underground. Why! Why did Sound Transit not follow what Japan and Europe did? …by putting their lines underground.
Three reasons. At the time the elevated/surface/underground decisions were being made (mid-1990’s) the predominant opinion in Rainier Valley was: We don’t want it under ground. And second was the disruption to the community during construction — memories of Third Avenue during downtown tunnel contruction were very fresh. And third was the much greater cost required to do something the public was saying not to.
And Yes, I was there.
Are you sure? I’ve always heard that they planned to put it underground but they didn’t end up having enough money to do it. Why would a neighborhood not want underground light rail?
Because underground light rail is a much bigger five-year construction hassle.
Also some in the neighborhoods didn’t want Rainier Valley to be “out of sight, out of mind” as suburban commuters whisked through the poor section of the city. The feeling was economic redevelopment was more likely to happen with an at-grade alignment.
There were a lot of opinions flying around during the ’90s and early 2000’s as the routings were discussed and the final alignment refined. Most people remember “Save Our Valley” because they were the last ones shouting (and suing) but other groups in the area had just as strong if not stronger feelings, it’s just that they were involved much earlier in the process. They also largely got what they wanted so there was no reason not to get out of the way and let Sound Transit do its thing.
The Save Our Valley folks — at least publicly — wanted it underground.
“at least publicly”. Publicly, they came to the game about four years too late.
That they did – a fact that must not be forgotten – if your group is not in on the planning from the beginning, your “right” to complain is severely reduced.
Ben and Chris pretty much have it right. At the time decisions were being made, the expressed community sentiment was for at-grade. It was only when construction began approaching, a few years later, that Save Our Valley formed up — out of a completely different set of people from the ones we were hearing from in the 1990’s. Yes, the claim was that they wanted it under ground, but in retrospect, that may have just been a strategy to kill the project or have it rerouted through the Duwamish Valley — making it just a commuter train for suburban folks.
Well, that was what I was alluding to with “at least publicly.” While there were people involved in it who thought — for social justice reasons — that SE Seattle should get a tunnel (and I can see their point since the north end is getting a tunnel to Northgate), I firmly believe that many Save our Valley supporters were just hoping to kill the whole idea.
What I remember is, “Roosevelt is getting a tunnel, why can’t we? Or if you can’t give us a tunnel or elevated, build somewhere else first and then come back to us.” I find it hard to believe more than a few people wanted it on the surface. And even if they did, the mood had changed before the route was finalized. In the end it came down to cost. ST said a tunnel was necessary in north Seattle because of the hills, but MLK was flat so they couldn’t justify the cost of a tunnel or elevated. ST was also worried that raising the total cost of the project would make it more likely to be voted down. (Even now you have people complaining Link is more expensive than MAX, even though Link is faster and more frequent because of that expense.)
It may have helped that Roosevelt was richer, whiter, more politically connected, and not a flat valley floor. But they were also IMBYs (“In My Back Yard”) to a greater extent than anywhere else.
The extra cost of tunneling has also cut back the initial segment to Husky Stadium, not 45th as originally promised, and caused the project to be 10 years behind schedule. It’s taken another vote and a raise in taxes to even get to 45th. The extra cost of tunneling under MLK probably would have sunk the entire project, it would have gone the way of the Green Line.
Not only did geography necessitate a tunnel under Capitol Hill, but also land prices and the fact that there is no street ROW whose width is similar to MLK from downtown to places north. MLK was built as wide as it was because it was going to be an expressway. It would have probably cost more than tunneling to purchase properties to create a similar alignment ROW from downtown to Capitol Hill and the U-District.
Frankly I don’t see the MLK segment as being a real detriment to the system. It only adds a minute or two to the travel time, the stations are easier to access than elevated or underground stations, and the entire streetscape has been improved. When the station areas are built out in another ten or twenty years they will probably be the nicest neighborhoods in Seattle.
Hmm, odd, I could swear both Japan and Europe have plenty of light rail lines that run at grade.
Here’s Japan:
http://en.wikipedia.org/wiki/File:Hiroden-5100-2.jpg
Germany:
http://en.wikipedia.org/wiki/File:Stuttgart_dt8.jpg
UK:
http://en.wikipedia.org/wiki/File:Croydon_Tramlink_Addiscombe_Road.jpg
Yep, there’s three and I’m sure I could find more examples with further searching.
Zurich has the highest transit mode share of any city and the core of their system is built on streetcars and trolleybuses. Of course transit vehicles have absolute priority at every intersection so that helps keep things moving along.
For a region with a very rich transit agency that now wants to build something that’s now going to resemble a metro w/ pantographs, it beats me. It would have been nice to shave off that extra 3-5 minutes by going 55mph elevated/underground. And using larger radii curves.
Those of you who say “walkable neighborhoods” and “people won’t see it”, look at Vancouver BC. Plenty of density around elevated and underground SkyTrain stations. Very walkable and appealing. Imagine how crazy the Canada Line will be in 20 years. It;s insane now! Or Portland, where they, at times, regret it wasn’t more out of the way because it goes so slow (and hasn’t grown in ride/share). The I-84 corridor is wonderful. Powering along at 55mph, but Lloyd Center to PDX is painfully slow for the distance covered.
IDK about you guys, but that gets me really excited for the 7 minute UW to Downtown Seattle transit time. None of that 24-27 minutes if-on-time garbage anymore.
No system will ever be “perfect” or satisfy all current or potential users. We have what we have and must work to make it work. Time to look ahead and deal with Bellevue!
Then if you count xx,xxx people in cars also please use x boardings = x people on Link. I know not all of them go down MLK. So how do you know that every car has 1.57 passengers and those passengers are unique. You claim over 30k people in cars. Why not 15k because you know they might drive home or make multiple trips in a day?
That’s moot anyway because you have no way of figuring out for sure how many people were on Link or in those vehicles when they cross X Street from an aggregate average daily number.
How much has delay increased for left turning vehicles due to Link? More importantly has total delay for all users at intersections increased due to Link? Can you answer that to prove your point?
Not answering for anyone, but I drove south on MLK today when Link service was suspended. I stopped at tons of red lights. I drove north when Link was going – and guess what? A train next to me timed my lights for me for three miles and I flew along!
Yay Link!
Really? That Link train did not stop for three miles? Must have made all those riders who wanted to get on of off at S. Othello or Columbia City sort of annoyed.
Sounds like the Link trains being out of service really screwed up the lights on MLK way, if your story is correct. Before Link, those lights were synchronized southbound in the afternoon, so you could drive south on it and hit all green lights. So now, Link trains have screwed that up?
Why are you driving a car down MLK? Don’t you know there is light rail along that street now? Shame on you. Get out of your car, and ride the wave!
Wrong Port City.
http://www.thewavetransit.com/
Oran, this is absurd. Of course some people in cars make multiple trips across MLK at Othello. And many people in Link trains make multiple trips across S. Othello each day. So what? I count each trip as one person crossing that intersection, even if it is the same person 10 times a day, that still counts as 10 trips, whether on Link or in a car. You really seem confused about a very simple concept.
If one person takes Link north across S. Othello in the am, and that same person then rides Link south across S. Othello in the pm, I count that as two trips. Doesn’t matter if the same person made both trips, it is still two different trips.
1.57 passengers/car is the national average. What do you mean by “unique”?
By your logic, ST has no way of knowing how many people are riding Link each day, beacause they only count a sample of less than 1/3 of the Link cars. All these figures are just estimates.
Of course, I don’t know how many thousands of hours per day are wasted by cars waiting at intersections because of Link trains. That is something that should have been in the EIS’s, but, as far as I know, was not even studied. A good question for you to research is why wasn’t delays for drivers and pedestrians at MLK intersections considered in the Central Link EIS’s?
How could total delay for a users at intersections NOT have increased due to Link? You have several anecdotes from actual LINK users right on this thread who describe how they have to wait through more than one red light to cross MLK now, because of Link trains. You don’t believe them? Better yet, you have not experienced this yourself?
Uh uh, you compared 8000 which is half of 16k boardings. At first, you compared 8000 to 35000. You’re confusing yourself.
You don’t even understand what I meant. I said nothing about sampling error. Sound Transit has all the data. You can know how many boardings by section if you know the specific on-off counts at each station but not for a daily route level count, which is what you’re using.
I don’t have a copy of the EIS so I can’t check but traffic impact analysis is an essential part of any major transportation project so it should be in there. Even the East Link analysis has LOS in it.
1.57 is a national average. What is the regional or local average? For what time of day? What proportion of that traffic is during peak?
Oran, 16,000 boardings is the total daily average in January for Link for all stations on the entire Central Link combined! I am just estimating how many of those boardings are people who are on Link trains when they cross S. Othello St.
I did not just arbitrarily divide 16,000 in half to get “unique riders” or whatever nonsense you are writing about. I am estimating how many people are actually on Link trains each day when the trains cross S. Othello St. in both directions combined.
Do yourself a favor and sit and think about this for a few minutes. Maybe it will come to you. I have things to do for a while this afternoon.
Apparently you didn’t read your own comment: “At S. Othello St. about half the total boardings of Link trains are on the trains. In other words, if there were 16,000 boardings per day in January, about 8,000 people per day rode Link trains across S. Othello St. per day, both directions combined.” So you can turn 16000 into a screen line estimate for Othello just by dividing by half? What kind of non-sense is that?
“I have things to do for a while this afternoon.”
Like riding Link?
But whatever, I have a paper to finish.
Acutally, I have ridden Link over 200 one-way trips, and have kept records of boardings and deboardings at every station on each trip. I could go back through those records and come up with a pretty good estimate of how many people are actually on Link trains as they cross S. Othello, but don’t feel like it. I am quite certain it is far less than half of total boardings. I mentioned that I was giving Link the benefit of the doubt on that. It is very likely no more than 40% of all boardings, and might be as little as 33% of all boardings. That would put the number at around 6,400 to 5,333, people per day riding Link trains across S. Othello ST., if that makes you feel any better.
But, I was not interested in trying to come up with a more-accurate estimate. I figured if I used a large number, like 50% of all boardings, then all you Link proponents would not argue about it. But, I was wrong about that, obviously.
Anyway, it sounds like you may have figured it out now, so that’s good.
I actually had to go to the east side today, and on the way back, after crossing the I-90 bridge, I took the exit to Rainier Ave, then turned off on MLK and drove two round trips between Mt Baker and Rainier Beach Link stations, just to check out the traffic light situation myself. I hit 7 red lights on that trip southbound, both times, and 5 red lights on that trip north-bound both times. So, I did not find that Link trains help traffic on MLK at all. And they obviously hurt traffic on cross streets.
I also saw intersections where 19 and 18 cars were backed up in the left-turn lane on MLK, waiting to turn left across Link tracks.
Going back to town, after I got back onto Rainier Ave. S., I drove all the way to the street which goes to I-5 without hitting a singel red light on Rainier Ave. S. So, the lights on Rainier Ave. S., on that stretch, at least, were synchronized better than the lights on MLK.
Most of what you experienced up there can be fixed by signals engineers. It takes time and information. You seem to have a lot of data, please send them to SDOT.
And you said nothing about cross traffic on Rainier. Were they inconvenienced just you can have smooth sailing down Rainier?
Any major street can have synchronized lights, and many in Seattle do. This does not impact cross streets, as, at each intersection, the light is red or green for a set period of time. It is just that, along the major street, the lights turn green in a sequence timed to the speed limit along that street (or maybe slightly below the speed limit).
The problem with Link along MLK is that link trains interrupt this timing sequence, so that cross streets sometimes do not get a green light when they are supposed to, and can have to wait an extra two minutes before getting a green — they have to wait until the next “scheduled” green light, because a Link train was allowed to cross that intersection when the light should have been red for MLK traffic.
It is not the synchronization of lights for traffic on MLK that causes probmes for cross traffic — it is that Link trains are allowed to interrupt that synchronization, to make lights for MLK turn green, when they “should” be red, according to the synchronization that is in place for motor vehicle traffic.
Totally different situation on MLK, because of Link trains. On Rainier, this interruption of the synchronization does not happen, because there are no trains running down Rainier Ave. S. So, streets crossing Rainier Ave. S. always get a green light every two minutes, or, however long the signal sequence is at that intersection.
I guess I should start taking videos and photos of some of this stuff. Can you give me a short explanation of how to put videos and photos up on the internet, so you, and others, can see them? Then, maybe I would not be accused of making things up.
Link trains can not interrupt or cause a signal sequence to be skipped. The only effect that Link has on the lights is that the green light for MLK can be lengthened or a cycle can be sped up so that a green light comes sooner so the trains can stay in sequence with the signal cascade on MLK. Link trains do not have signal preemption at intersections, this is why trains often times wait at the stations along MLK, so they can enter the signal cascade at the right time. If the trains’ headways get too short, or they enter MLK too soon after another train, or they get behind the signal cascade they will end up stopping at lights along MLK.
If you see traffic getting backed up on MLK it’s because there’s too much traffic, just like any of the thousands of other streets that get backed up yet don’t have trains running on them.
“the green light for MLK can be lengthened or a cycle can be sped up”
Same difference. The shorter the green light for traffic on Othello, or other cross streets, the few cars can cross MLK on that green light, resulting in backups on cross streets.
Is this also true of left-turn signals for cars on MLK? Those left-turn greens are never skipped if a Link train causes the green for MLK to be longer than it would otherwise be?
I am going to have to spend some time at intersections on MLK and see this in action. If what you are saying is true, then Link trains should have to stop at some intersections on every trip down MLK, and I know that this does not happen on every trip.
But, even if you are correct, why should this be done? Link trains should be able to maintain a constant 35 mph on MLK, so they would hit every green light, in the peak direction. The only greens they would miss on occasion, would be the first light after each station. Just let Link trains wait for the normal green when leaving stations on MLK, and they would not cause any disruptions.
In other words, if Link trains are causing almost no disruption to the signal synchronization, as you seem to be saying, why give them any priority at all? If they can’t maintain 35 mph, except when they stop at stations, let them wait for a red light.
You know for someone who advocates for building BRT instead of rail transit you have a rather odd hatred of transit signal priority.
Or do you not realize that part of what makes BRT work is giving buses their own lanes and signal priority at intersections?
Would you have the same complaints about the transit signal priority on MLK if instead of Link it was some bus lanes and a BRT version of the 8 and 42 running down that street?
Or do you somehow think signal priority magically works differently for buses and rail?
Skipping a signal phase and changing the duration of a phase are not the same at all. The majority of cars, if not all, on the cross streets can still get through during a shorter phase, because traffic is light on most of the cross streets. Skipping a phase would cause bigger backups.
Why would trains have to stop at some lights on every trip? In general the trains don’t leave the stations until the signal computer is ready to initiate the signal cascade along MLK.
“Those left-turn greens are never skipped if a Link train causes the green for MLK to be longer than it would otherwise be?”
The left turn phase can be changed to occur before or after the train clears the intersection, it depends on what’s appropriate for the situation. The computer knows minutes ahead of time when a train is going to be at a particular intersection, a train only takes 10 seconds to clear an intersection, and a complete signal cycle only takes 2 minutes, so it’s not really a big challenge for a computer to coordinate.
You’ve really latched on to the word “priority” without a clear understanding of what it really means and are making it into a much bigger deal than it actually is. Priority simply means that the train can cause the signalling computer to initiate a sequence of minor changes that give the train the highest probability of getting from one station to the next without stopping. The system doesn’t work just arbitrarily, it’s been designed by professional traffic engineers who spent years in school and who spend every day thinking about how to make the system work best for everyone. Do you really think that you know better than them?
How would total delay not increase? Well, if more people rode Link and the 8 instead of driving!
I’d bet that delay for motorists has probably decreased now that MLK has a state-of-the-art traffic control system. Before the street was rebuilt for Link a lot of the signals on MLK were still on fixed timing and weren’t synchronized at all. I’ve yet to see any significant traffic backups, even at rush hour. The traffic on MLK is nothing compared to streets like Roosevelt or 45th. Ever been stuck at 50th and Stone Way, the signal cycle there is over 5 minutes at rush hour!
Anecdotally, because of this thread I took special note of how many cars were waiting at cross streets along MLK when I took the train at 5:00 yesterday. The longest queue I saw was eastbound on Graham, 6 cars waiting to cross MLK and 3 waiting to turn left. The next longest was eastbound at Othello, with 8 cars waiting to cross MLK. Of course those queues would exist whether or not the train was there, since that’s just the way intersections work! Maybe we should have rebuilt MLK with roundabouts instead!
If complaints are dropping, it just means more people are giving up and crossing against the light.
Why am I waiting for a light when the street is empty?
Also, why is the light crossing the southbound lanes tied to the light crossing the northbound lanes. There’s a safe place to stand in the middle, make these separate signals.