In the posts I’ve written about the proposed Fall 2012 restructure, one complaint I’ve heard repeatedly is from Route 5 riders in Greenwood and points north, regarding diminished reliability and speed in exchanging Aurora for Dexter, due the attendant exposure to delays from the Fremont Bridge and Fremont traffic generally.
Fortunately, Metro collects data that can allow us to quantify the effects of this change, and I’ve assembled charts that will allow readers to do just that. There are two timepoint pairs involved:
- 3rd & Union to 34th & Fremont (and vice versa). This is the travel time of the 26/28 pair from Downtown Seattle to (and from) the heart of Fremont.
- 3rd & Pine to 38th & Fremont (and vice versa). This is the travel time of Route 5 from Downtown Seattle to (and from) its closest current stop to Fremont.
The additional travel time of about one minute between Union and Pine conveniently offsets the approximate travel time from 34th to 38th, so these charts provide an excellent travel time and reliability comparison between the current alignment of Route 5 and the proposed reroute to Dexter. Some points to bear in mind, when reading these charts:
- Express service on Greenwood and Shoreline via the Aurora bridge will operate during the peaks, in the form of either Route 5X or 355.
- The underlying data run from February through May, so neither the speed and reliability improvements from the Wall/Battery bus lanes, nor from the Dexter reconfiguration will be reflected in this data.
- Arguably the most precise timepoint comparison just to compare Aurora and Dexter would be from Aurora & Denny and Dexter & Denny to Fremont, but that data doesn’t exist (as far as I know). On the other hand, these two timepoint pairs most accurately characterize what riders experience under the current 5 versus the proposed revised 5.
Charts after the jump.
This chart shows travel times with error bars indicating the standard deviation of each travel time (more on that below). During the mornings and evenings, Aurora is about five minutes faster, widening to six or seven minutes during the peaks and midday. Between 17:00 and 18:00, reliability and travel times on both routes get spectacularly worse.
The same chart southbound. In the evenings, Dexter is only a couple of minutes slower, rising to about five minutes slower in the peaks, and roughly four minutes midday.
This chart shows just the standard deviation of the average northbound travel times. Standard deviation is a mathematical measure of how “spread out” a set of numbers are. In this context, it’s a little hard to define both accurately and simply, but the best I can think of is this: For a route with a standard deviation of (say) 2.5 minutes, the vast majority of buses will be no more than 2.5 minutes late. So the higher the number, the less reliable the route. Here we can see that, for most trips except in the early mornings and late at night, Dexter is about a minute less reliable.
This is the same chart southbound. The data here are suggest that Dexter and Aurora are similarly reliable heading southbound.
So, overall, Dexter is definitely slower and less reliable northbound, and a little slower southbound. Where you stand on this proposed reroute probably depends on where your stop is, but the discussion can now proceed in the presence of some facts.
22 Replies to “Chartapalooza: Aurora versus Dexter”
Will there be any new transit-only or BAT lanes, signal priority (including queue jumps), or other new transit infrastructure along the shared 28/E path by the time the ribbon is cut on the E Line?
Whoops, … shared 5/E path …
I don’t know of any although I haven’t specifically asked Metro. There is a continuous bus lane on Battery from 3rd to Denny, and a bus lane Wall from Denny to 4th, with a queue jump at 4th. North of Denny, Aurora is almost a freeway until Winona, and I don’t know what else you’d put there.
Another point: If the data was from this year, then much of it was during Dexter Ave construction/repaving (from March) which would affect travel time and reliability on the 26/28.
What do you think of capacity on the new 5? Is an articulated bus every 10-15 minutes during peak enough to handle the demand from both Fremont and Greenwood/Shoreline?
Not on Sounders game nights, no. During peak that really needs to be 10 minute service in my experience – although I don’t know many folks will take the 28X instead.
Keep in mind there will also be the 18 going through Fremont then down Westlake, which will be frequent-service and presumably all-artic. With those two routes, I don’t think capacity to Fremont will be a problem.
“The additional travel time of about one minute between Union and Pine conveniently offsets the approximate travel time from 34th to 38th, so these charts provide an excellent travel time and reliability comparison between the current alignment of Route 5 and the proposed reroute to Dexter.”
This is a hole in your argument. You’re comparing a two block difference Downtown on a street with bus priorities to a highly congested four-block section of one of Seattle’s densest neighborhoods that is also drawbridge adjacent. You’re also not allowing for the increased number of folks likely to be transferring at 34th and Fremont due to the other changes proposed in Metro’s plan.
Is it so hard to say that it will take longer for the average 5 local rider to get Downtown should the change go through? Even for folks who support the changes it seems appropriate to acknowledge that the changes will have real impacts on actual riders.
“During the mornings and evenings, Aurora is about five minutes faster, widening to six or seven minutes during the peaks and midday.”
An unblockable transit only tunnel under the canal would move a lot of passengers, especially if the South Lake Union Streetcar gets a Ballard extension. A dock employee told me the canal is 40′ deep at Fremont. Wonder what the soil is like?
As an alternative, transit-only lanes approaching the bridge might work- along with bus-only (and streetcar-only) signals onto the bridge.
Am I right that the Fremont Bridge took the old interurban across the canal? Also curious how much right-of-way is still available from streetcars past.
both the University Bridge and the Fremont Bridge had streetcar lines that crossed them … the Ballard Bridge did too
Don’t forget there used to be a Stone Way bridge as well.
The Stone Way Bridge closed when the Fremont Bridge opened. But the Stone Way bridge did also carry streetcars. Though if your point was that we could maybe build another Stone Way Bridge, while the Stone Way ROW still extends all the way to the water on the north side of the canal (as is the case with many streets in Seattle), the ROW on the south side of the canal seems to’ve been given up. But then again, that’s what eminent domain is for, n’est-ce pas?
(There was also an NP rail bridge that crossed the canal diagonally to the southwest starting at 8th Ave NW, though being NP it was for freight not streetcars. Apparently it wasn’t completely torn down until the ’70s.)
Apropos of ROW from streetcars past, the Westlake ROW is 150′ wide from Valley to Dexter/Nickerson/4th/Fremont, presumably thanks to all the old rail that used to be along there, both streetcars and freight. Of course at the Fremont Bridge the ROW narrows to basically just the width of the bridge.
Well, specifically, there was an older Fremont Bridge when the waterway was lower (before the Ship Canal). The Stone Way bridge was an interim bridge while the current Fremont Bridge was built.
@Mike: Yeah, I hadn’t realized that. Apparently there were actually two Fremont Ave bridges prior to the current one, with the Stone Way bridge being built in between bridge #2 and bridge #3. Paul Dorpat has a great discussion of all the machinations here, as do the comments at the flickr page for a 1911 SMA photo of Fremont Bridge #2.
Bruce, thank you for inserting facts into this discussion. Obviously, being a Bellevue Resident, I don’t have a great grasp on the Seattle network, but I am always a fan of fact based reasoning. Well done!
How many of the 5 riders heading downtown, do you think will divert to the 28X or 358 to stay on Aurora avoid going through Fremont?
I wouldn’t care to guess a number or percentage. North of 100th, the 28X will only run at those times the 355 will also run. Most of the area south of 85th, there’s a steep elevation change between Greenwood and 8th, so I doubt you’ll see much diversion to the 28, except if there’s actually a stop right there by Fremont (on 38th; which I presume there will be). South of 85th St, the steep grade and the zoo are disincentives to use the 358, as is the cemetery between 110th and 125th. I think there’ll be more diversion to the express services, 355 and 5X.
More generally, I think riders — particularly spontaneous riders (rather than downtown commuters, who have the same schedule most of the time, and can ride the expresses designed specifically for their needs) value frequency over speed. Suppose you’re near Greenwood, and can walk five extra minutes to a bus that’s ten minutes faster but runs every 30 minutes vs 15 minutes. Most of the time, you’ll get there sooner on the slow but frequent bus.
The restructure proposal would swap the tails of the 28 and 5. These routes can either (1) connect to Lower Fremont (slower to downtown) or (2) express to downtown on Aurora. The restructure just switches which does which. Metro is betting the 28 riders are more likely to want to go to downtown fast, while 5 riders are more likely to want to go to lower Fremont. They could be right.
It’s also worth noting that the 28X riders would have only one service pattern (the express) and Greenwood riders have a well-established express overlay service that would not change.
The creation of routes 31 and 32 also turns Fremont into a transfer point for those using the current route 30 on Westlake or the west part of SLU to make a frequent-service transfer to the U-District. Similarly, Queen Anne riders could transfer at SPU from the improved 3/13.
This network proposal wasn’t just pulled out of a hat.
I ride 28 every day from Fremont to Greenwod or 5 from 39th to Greenwod (I live on 4th, so directly between those two). My experience shows time and time again that 5 arrives usually on time, while 28 arrive with 15-20 minute delay constantly.
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