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Want bikeways for everyone? Nix the mixing, new research says

Posted by on December 19th, 2019 at 2:45 pm

This protected intersection in Salt Lake City, Utah was rated comfortable by the largest number of respondents.
(Photo: TREC at PSU Researchers)

With protected bike lanes all the rage in Portland and throughout the U.S., a big question remains: What about intersections? After all, protection on the blockface doesn’t mean much when you come face-to-face with a drivers’ car at the intersection.

One of the lead researchers, Christopher Monsere, Ph.D.
(Screen grab from TREC video)

New research released today from the Transportation Research and Education Center (TREC) at Portland State University set out to learn more about that question. What they found is that there are really only two types of bikeway designs that most people feel comfortable using, and they both include almost total separation from drivers.

The research team of Chris Monsere, Nathan McNeil and Yi Wang of Portland State University, along with Rebecca Sanders, Robert Burchfield (formerly PBOT’s head traffic engineer where he oversaw installation of Portland’s first-ever protected bike lane on SW Broadway) and William Schultheiss of Toole Design Group south to quantify the relative comfort level of a variety of bikeway design types among a variety of people.

Instead of crash data, they showed subjects helmet-mounted videos of bike lanes and asked, on a scale of 1 to 5, how comfortable they’d feel riding on it and whether or not they’d consider riding on it with a 10-year old child. A total of 277 people watched the clips during surveys taken in urban and suburban locations in Oregon, Minnesota, and Maryland. Researchers gleaned a total of 7,166 ratings from the surveys.

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Five intersection types located in Seattle, Denver and Portland were studied: a separated bicycle traffic signal phase; a “bend-in” design that shifts the bike lane in toward other lanes; a “bend-out” design (a.k.a. protected intersection) that shifts the bike lane away from other traffic; a straight path that stays separated right up to the intersection; a “lateral shift” design that swaps the bike lane with other lanes and moves riders across the path of drivers; and a “mixing zone” design that terminates the bike lane and throws riders into the mix with turning drivers.

New bike lane on N Denver Ave. (Don’t do this if you want novice/new people to cycle.)
(Photo © J. Maus/BikePortland)

The findings show that comfort ratings plunge in places where bicycle riders are forced to mix with drivers prior to an intersection. If cities want to attract “interested but concerned” riders, researchers recommend only two of the designs: a separated bike signal phase or a protected intersection. “If you really want a bike network that’s comfortable for all ages and abilities,” said Chris Monsere from his office at PSU this morning, “It’s really just those two.”

Portland has a few bike signal intersections (NE Lloyd and Interstate at Peace Park, N Rosa Parks and I-5) and just one protected intersection (and it’s very new and in a relatively hidden location (NW 20th and Vaughn) without much traffic).

Unsurprisingly the intersections with the lowest comfort ratings were mixing zones and lateral shifts — where bicycle riders are forced to share space with other vehicle users. Mixing zones are a popular treatment at the Portland Bureau of Transportation. They just installed one on N Denver Avenue at Lombard (see photo at right).

Here’s the clip of a lateral shift design that got the lowest ratings:

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And here’s the clip of the protected intersection (in Salt Lake City, Utah) that was rated most comfortable:

When asked the question about biking with a 10-year old, the straight protected bike lane (not at an intersection, used as a control) rated the highest with 89% of respondents saying they’d ride it with a child. Second place on the comfort rankings was a bend-in design from Denver, Colorado with 70% of respondents saying it would be comfortable. The later shift and mixing zone designs — both prevalent in Portland — were ranked as comfortable by only 31% and 25% of respondents, respectively.

There’s some data in the study that shows protected intersections result in more interactions between bicycle and car users — but is still considered comfortable because of the visibility and slow speeds the design encourages.

Another interesting aspect of this study is that researchers broke down results based on different rider typologies so you can see how “interested but concerned” riders’ views differ from “bike-inclined” (non-riders), or “strong and fearless”.

Learn more about the research and find all the downloads you need at trec.pdx.edu.

— Jonathan Maus: (503) 706-8804, @jonathan_maus on Twitter and jonathan@bikeportland.org
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NOTE: We love your comments and work hard to ensure they are welcoming of all perspectives. Disagreements are encouraged, but only if done with tact and respect. BikePortland is an inclusive company with no tolerance for discrimination or harassment including expressions of racism, sexism, homophobia, or xenophobia. If you see a mean or inappropriate comment, please contact us and we'll take a look at it right away. Also, if you comment frequently, please consider holding your thoughts so that others can step forward. Thank you — Jonathan

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Babygorilla
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Babygorilla

Related, but does anyone know if the work on W Burnside and 18th/19th intesection is effectively done or will there be changes to signals / timing?

Its seems more dangerous to make a left (a route probably about 50% of the bike traffic here takes) because the signals haven’t been altered to give any sort of lead time for the new infrasturcutre. If you follow a “copenhagen left” as directed by the curbs and green paint, it routes you right into traffic crossing 19th toward the stadium and seems like its inviting someone on a bike to get t-boned.

Zach
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Zach

It’s so dumb how they need to jump through all these hoops of doing surveys and collecting data to even come close to choosing a design that is OBVIOUSLY better. But whatever it takes, I guess.

Zach
Guest
Zach

In other words, JUST COPY THE DUTCH. THEY ALREADY FIGURED IT OUT.

B. Carfree
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B. Carfree

In the end, it comes down to severely restricting car use so that people can safely, cleanly, and comfortably move about our streetscape. We’re doing a lot of work to avoid taking this now-necessary step.

El Biciclero
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El Biciclero

Except for 40-mph and above arterials (and similar) I would much rather mix with “cars” on a nice wide street than with pedestrians and wobblers in a narrow, curb-delimited chute.

As for copying the Dutch, yes, let’s, but we should start with signal optimization and legal changes before we attempt to copy infrastructure designs that will make bicycle travel a ponderous plod that bicyclists only use under threat of citation.

I have no interest in creating yet another online “free” account so I can download the complete report, but I would be curious to know the differences in attitudes between the “interested but concerned”, and “bike inclined”. Would people start out wanting protected lanes, but find them frustrating after gaining enough confidence in their riding ability? My own experience is that rather than being freeing, so-called “protected” infrastructure is confining, and has served as more of an impediment than a facility. Not that we shouldn’t have such infrastructure, but there has to be an opt-out when it just doesn’t work for everyone. First repeal ORS 814.420, then build all you want and see what gets used when use isn’t forced. Cage the cat, not the bird.

David Hampsten
Guest

I note that the best solutions are typically the most expensive ones, both in materials and space used in the right-of-way. Does Portland even have an intersection as wide as the one in Salt Lake City shown in the video? I know East Portland enough that 122nd at Division is narrower, and that’s among the widest in Portland, not to mention far busier.

I’m sure if we were like the Dutch and didn’t spend trillions on useless foreign wars and preparing for WW3, we too could afford to build protected bike lanes, ocean dikes, freeways, and river tunnels like they do. Unfortunately, we as a society have spent the last 150 years electing presidents and congresses who seem to love war and supporting the military-industrial complex over building boring infrastructure.

GNnorth
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GNnorth

I’m with El Bicilero on taking my chances along cars and other traffic instead of a multitude of pedestrians and other non-vehicular users, they’re drivers normally anyways but are more erratic once outside the car. I’ll never lend my support to anything that has a square curb, those are designed to help autos “bounce” back onto the roadway and unless one can bunnyhop well enough it’s going to take down a cyclist almost every time. While I see the calls for more bikeways being necessary we need to make the distinction that’s for urban users in a city landscape and does nothing for someone like myself who rides 25 miles in the AM to work and a large majority of it is on rural-ish roads.

Johnny Bye Carter
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Johnny Bye Carter

“protected bike lane on SW Broadway”

Just another broken-record post pointing out that there is no such bike lane there and that the term “protected” continues to be misused.

Johnny Bye Carter
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Johnny Bye Carter

“Here’s the clip of a lateral shift design that got the lowest ratings:”

Car is obstructing the lane here forcing the rider to squeeze into a smaller lane closer to car traffic.

“And here’s the clip of the protected intersection (in Salt Lake City, Utah) that was rated most comfortable:”

This video does not show an active conflict with a car, so of course will be selected as the preferred intersection.

These videos are not equivalent comparisons.

When I envisioned myself going through these intersections I thought of the worst case scenario where in the lateral shift scene the station wagon (now called SUV) driver sideswipes me as they turn into the lane bouncing me to the right road shoulder, and in the protected scene I get hit with the grill of the car and possibly run over.

I chose the lateral shift scene. Unless you add separate signal timing to the protected one so there’s never a conflict then I’m going to be way more nervous than I would be of getting sideswiped in my own lane.

Jim Lee
Guest
Jim Lee

Kate
This is an important point. Roadway widths in Salt Lake City are 130 feet wide! Many of Portland’s five lane arterials are 66′ feet wide, less than half that. Some get up to 72 but generally there is a lot less space to work with unless they can purchase adjacent right-of-way (businesses and homeowners are generally not psyched about that).It might have been a more useful comparison for us portland-based folks if they had used a clip of a Portland protected intersection (like Burnside/19th) but that probably wasn’t ready when they conducted the research. Agreed with a later commenter that I didn’t like it for heading left onto Alder St and into downtown, I’ll continue to take the lane and turn left. But I also recognize that I’m not the category of rider that infrastructure was built for.Recommended 0

And SLC blocks are 600 feet long, compared to 200 feet in PDX!

Traffic there is like drag racing between signals.

They do have MAX-like light rail, and fairly frequent heavy rail for the many miles between Ogden and Provo–powered by filthy old diesel locomotives.

Also very bad air pollution stacked up against the Wasatch Mountains, especially in winter.

Carrie
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Carrie

Is the horribly overbuilt bike roundabout at SE Mitchell and Milwaukie considered a protected intersection? This former ‘vehicular cyclist’ is becoming more and more an advocate of protected infrastructure as I observe SO MANY people driving in the bike lane on Willamette (I was nearly clipped from behind last night on my way home and I was solidly in the middle of ‘my’ lane). However we MUST be designing for the volume of cycling we want to see, not for the volume we currently have. Back to the horrible roundabout in my neighborhood — I’ve used it once. It’s narrow, confining, it makes me slow down when I don’t need to, and it forces me to go a direction I don’t want to go. There’s no way to for more than 2 cyclists at a time to be in it and you definitely couldn’t pass someone. If that’s what PBOT is building, I want none of it, though I also really don’t want to get hit while in the bike lane either.

Clark in Vancouver
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Clark in Vancouver

Vancouver, BC now has a few protected intersections. Using them is really nice and just seems so natural now. There is no sense of being confined or anything like that. It feels more like no longer being disenfranchised.

Loshad
Guest
Loshad

They should present a video to people of riding in the trash-filled “protected” bike lane on 2nd Avenue and nearly getting hit by turning cars & pedestrians every block vs. riding in the middle lane of 4th (like you used to be able to do on 2nd).