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Bike-friendliness and walk-friendliness are actually pretty different, study says

Posted by on October 28th, 2015 at 1:05 pm

Rosa Parks Way -3

Rosa Parks Way.
(Photo: J.Maus/BikePortland)

Portland has a long way to go, but it’s one of the country’s best cities to bike in. Sad to say, it isn’t yet one of the country’s best cities to walk in.

So why do so many people, here and elsewhere, speak as if there’s an activity called “bikingandwalking” that can be encouraged all at once?

Some new research from a recent Portland State University engineering grad helps to disentangle the science of these two awesome activities.

“Highly walkable and highly bikeable environments are quite different,” writes Christopher Muhs (who’s now a transportation engineering assistant at local firm DKS) in his paper. “Two of the most divergent characteristics are travel speeds and distances. … It follows that pedestrians tend to travel much shorter distances than cyclists.”

Muhs, working with PSU professor Kelly Clifton, looked at various studies that found correlations between characteristics of cities and neighborhoods and the amount of biking and walking that happens in them — number of intersections per mile, for example, or the size in square feet of local retail stores. Here’s one interesting discovery:

The magnitudes of the impact of built environment variables on walking are often much larger than those with bicycling. This is also true of trip distance or travel time variables. In three US studies, the magnitudes of the trip distance coefficient for walk mode choice were more than three times those of the corresponding coefficient for bicycling.

In other words: it takes a lot longer to rebuild a city into walk-friendliness than it does to rebuild it into bike-friendliness.

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Here’s another insight: it might be possible for a city to be too dense for biking.

Cycling may also be sensitive to minimum and maximum thresholds. For example, high-density locations correlated with central business districts, downtowns, and regional centers may not provide environments conducive to cycling. The greater intersection densities and traffic control often mean more stops, slowing travel speeds. … On the other end of the spectrum, low-density environments may not provide destinations within a reasonable distance for utilitarian cycling but may offer better recreational opportunities.

Muhs also touches on this perennial problem:

It has also been acknowledged that cyclists may be more multimodal than other travelers, due to weather or other situational constraints. … Nearly all of the literature we reviewed consisted of cross-sectional studies, with individuals observed at just one point in time. The lack of longitudinal studies on bicycling makes us raise the question: Is our current understanding of cycling behavior based on a slim percentage of the overall cycling population?

Yes indeed.

The paper from Muhs and Clifton was published this fall in the Journal of Transportation and Land Use.

— Michael Andersen, (503) 333-7824 –

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NOTE: We love your comments and work hard to ensure they are productive, considerate, and welcoming of all perspectives. Disagreements are encouraged, but only if done with tact and respect. 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

  • Chris Smith October 28, 2015 at 1:13 pm

    I’ve often hypothesized that my neighborhood in NW Portland has lower biking rates because it is SO walkable. (of course we could use improved bike infrastructure as well)

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    • Michael Andersen (News Editor)
      Michael Andersen (News Editor) October 28, 2015 at 1:19 pm

      I’m sure that’s right – which speaks to the fact that for most BikePortland readers, the outcome that matters is probably biking+walking. Muhs is exploring the means to maximize both of those numbers.

      Also, worth noting that NW actually probably has the highest bike-use-to-bike-infrastructure ratio of anywhere in the city. I thought a lot about Northwest when was in Montreal this year — but I’m saving that post for when we do Northwest Portland Week!

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      • Chris Smith October 28, 2015 at 2:14 pm

        Interesting. I believe Roger Geller has data that the neighborhood greenways in NW perform poorly (mostly in terms of of too much auto traffic).

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        • gutterbunnybikes October 28, 2015 at 8:33 pm

          It’s silly to base performance of greenways by autotraffic. If conflicts rates are low/unchanged – who cares.

          All that mumbo jumbo on proper auto and bicycle counts was made up to begin with (quite possibly a dart board was involved in the decision making process) some thirty years ago, and was likely originally designated as a standard to choose roads in which bicycles would interfere with automobile traffic the least while still providing routes that flowed well (less stops).

          Likely part of the performance issues with the westside greenways are that many (like myself) don’t even bother with Greenways (or even look for lanes) on the west side. It’s easy and practical to take the lanes on nearly all of the streets. If it wasn’t for this site, despite frequent trips downtown and NW/Pearl for over 20 years, (including living in close in SW and NW with only a bicycle and a bus pass for a few of those years) I wouldn’t even be able to tell you where the bike lanes and greenways are.

          Truth is despite all the hype of sexy European infrastructure (though everyone’s favorite bike city has been in decline for nearly a decade) and the bashing of the greenway system by the bicycle community, in Portland anyway- the greenway system is the best infrastructure we have, it delivers mileage, “safety”, and effectiveness.

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          • soren November 1, 2015 at 2:42 pm

            “It’s easy and practical to take the lanes on nearly all of the streets”

            Is our current understanding of cycling behavior based on a slim percentage of the overall cycling population?

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      • maccoinnich October 28, 2015 at 5:49 pm

        Looking forward to Northwest Portland week!

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    • chris October 28, 2015 at 1:56 pm

      Like a Flanders bike/ped bridge over 405.

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      • Chris Smith October 28, 2015 at 2:12 pm

        Definitely! But it wouldn’t change my behavior much.

        I bike daily, but almost always by using the Overton neighborhood greenway to access either Naito or NW 19th to get to downtown or the east side.

        I DON’T bike for trips within the neighborhood, and I can meet a lot of my daily needs in the neighborhood, because I can access everything in a 10-minute walk.

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        • soren November 1, 2015 at 2:56 pm

          How is this any different from the inner SE east? I shop, eat, and drink in my neighborhood by foot 95+% of the time. Shopping, in particular, is far more convenient by foot than in the inner SE than in NW portland. Despite this my neighborhood has a cycling ACS mode share approaching 20%.

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          • soren November 1, 2015 at 2:57 pm


            “by foot in the inner SE”

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    • Dave October 29, 2015 at 9:50 am

      Having lived there for 5 years earlier in my life I would agree–there’s such a thing as too short a trip to bother with a bike.

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  • Captain Karma October 28, 2015 at 1:20 pm

    Your lead photo appears to be Abbey Road. Just need a VW beetle in there.

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    • Spiffy October 28, 2015 at 2:13 pm

      I don’t see any Volkswagens at all!

      but there are bikes parked across the street at the yard sale… that’s my favorite way to yard sale… just hook up the trailer on the weekends and hope to find fun things… also, lemonade stands on bike streets…

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    • paikiala October 29, 2015 at 12:08 pm

      Concord and Rosa Parks (looking west at the north leg)

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  • Scott H October 28, 2015 at 1:25 pm

    “It might be possible for a city to be too dense for biking.” Anyone who’s biked in Manhattan knows this is complete horse manure that the authors are simply attempting to glean from the actual data.

    Come to think of it, Manhattan pretty much flies in the face of the entire study. Manhattan is a great place to walk and to bike. If you need to go downtown or uptown you grab your bike. If you’re only going several blocks, you walk. If it’s pouring rain, you take the subway.

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    • Chris I October 28, 2015 at 1:29 pm

      And the big biking cities in Europe are incredibly dense. They just allocate their street space to better facilitate cycling than we do here in America.

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      • B. Carfree October 28, 2015 at 7:06 pm

        Or the people tend to use bikes as substitutes for walking. I think the median trip length in Copenhagen is something like 300 meters.

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    • Ian October 28, 2015 at 11:41 pm

      but it does make sense to that Portland could be just about the right density for biking, but way too spread out for much walking

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    • lop October 29, 2015 at 3:19 am

      Manhattan is a great place to bike? Then how come so few people bike? ~0.5% of peak hour inbound CBD screenline, ~0.7% all day.

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    • Jonathan R October 29, 2015 at 5:07 am

      As a Manhattan resident and daily bicyclist, I can attest to the truth of this statement. On my block (no crossing streets), I have day care, flower stand, restaurant, convenience store, pharmacy, fish restaurant, pizza parlor, subway entrance, newsstand, and supermarket. Everything I need, and too close to make bicycling worthwhile. The farmers’ market is about the farthest unique thing away, and that’s only a 20-minute walk.

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      • davemess October 29, 2015 at 11:12 am

        So where are you daily cycling to?

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      • wsbob October 30, 2015 at 12:22 am

        “…and that’s only a 20-minute walk.” Jonathan R

        About a mile distance perhaps. I’ve given some thought of late, about which Portland neighborhood may currently be closest to having the potential road travel functionality of Amsterdam (not having been there first hand.). Could be, an area including part of The Pearl, two or three blocks to either side of Burnside, including Powell’s and Whole Foods, and going some blocks east and west. Not nearly as well equipped with amenities in the concentration you describe your Manhattan neighborhood as having…but maybe is slowly getting there.

        Some aspiring Portland politician seeking to be mayor, could possibly acquire some visionary cred by putting effort and thought into having the city actually work to realize a Portland neighborhood characterized by a street travel functionality related to that of Amsterdam: many, many more people walking about and biking in that neighborhood, then traveling by motor vehicle. There would be people thinking either that such a person had one of the best ideas of any politician in a long time…or that they were complete ‘out there’, out of touch with reality.

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  • davemess October 28, 2015 at 1:30 pm

    This seems like a pretty obvious hypothesis to test.
    My own house has a very bikeable bike score (79) and a somewhat walkable (moderate for Portland) walk score (68).
    I’m sure my neighborhood is not unique to this type of discrepancy in Portland.

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  • Matt October 28, 2015 at 1:40 pm

    When I moved here from the east coast, I couldn’t believe that I had to push a button for the privilege to cross the street and that cars can turn on red pretty much everywhere, even busy intersections with people trying to cross all hours of the day. It’s a suburban model applied to some of the densest parts of the city. Makes no sense.

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    • Stephen Keller October 28, 2015 at 1:51 pm

      Two things I’d like to eliminate in the metro area are turns on red and the those pesky yellow blinking left turn signals. Together those two account for about half the stress in my commute.


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      • Spiffy October 28, 2015 at 2:16 pm

        as a driver I love those blinking yellow left turn arrows… I used to just treat the red arrow like a stop sign…

        but with all the left-turning idiots running into people biking lately I’m willing to give up the yellow blinking arrow for the safety of others in the face of idiocy…

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    • davemess October 28, 2015 at 4:23 pm

      you can still cross as a pedestrian if you have the green.

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    • Brad October 28, 2015 at 11:31 pm

      Portland is a walker’s (and biker’s) paradise compared to what I had to deal with in Wisconsin. Sounds like I need to spend some time on the east coast!

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      • Scott H October 29, 2015 at 6:43 pm

        This relationship applies to most aspects of life. The east coast pretty much has everything figured out, maybe with the exception of beer. The west coast is still figuring some things out and has some catching up to do. A lot of the states in the middle seem to be regressing backwards.

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  • soren October 28, 2015 at 1:45 pm

    Is our current understanding of cycling behavior based on a slim percentage of the overall cycling population?

    Why does Muhs hate bike portland commenters?

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  • ethan October 28, 2015 at 2:11 pm

    If Portland (and PBOT) really cared about walk friendliness, they would stop installing (and start removing) beg buttons.

    It’s ridiculous to me that intersections are being “upgraded” with these buttons that make people wait when we’re walking so that other people don’t have to wait at all.

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    • John Liu
      John Liu October 28, 2015 at 2:48 pm

      Beg buttons – if implemented well – allow the pedestrian to stop traffic and cross when he wants to, instead of waiting through a fixed signal cycle. And they let drivers continue through instead of idling their engines pointlessly at an empty crosswalk. Maybe they should be called “command buttons”.

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      • ethan October 28, 2015 at 3:01 pm

        The ones they’ve installed recently in the Lloyd District are the opposite of that.

        Many (all?) of them are not programmed so that people walking get the walk button UNLESS someone presses the button prior to the signal phase.

        This has decreased walkability and led to an observed increase in people disregarding the walk phases completely.

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      • Alex Reed October 28, 2015 at 3:32 pm

        Is there a single beg button in Portland at a signalized intersection (not just a pedestrian crossing) that is implemented that way? I have not run into one that I’ve noticed; all seem to have lengthy average waits for pedestrians. I agree that you express something that could in theory be programmed into the signals, and I think should be, but I haven’t seen PBOT actually do it anywhere.

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        • John Liu
          John Liu October 28, 2015 at 8:05 pm

          Hmm, that sounds like bad implementation. I haven’t paid attention to the buttons in the Lloyd district, but I will.

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        • Carrie October 28, 2015 at 9:18 pm

          Actually Alex, the button at SE 15th that crosses SE Tacoma in Sellwood is pretty responsive — it stops traffic pretty quickly compared to most of the others around town.

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          • Alex Reed October 29, 2015 at 3:03 pm

            So… that’s a pedestrian crossing only, not a full intersection. Yes, there are some pedestrian crossings where that is the case. But I’m not aware of any full intersections (where cars see stoplights coming from all four directions). The vast majority of beg buttons and related pedestrian delay in Portland occur at full intersections, I’d wager.

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            • John Liu
              John Liu October 29, 2015 at 7:35 pm

              42nd at E Burnside. Roll up on a bike, push the button, and Burnside traffic gets a red light quickly. I’ve never tried pushing the pedestrian button, but I’d think it works the same.

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              • Alex Reed October 30, 2015 at 10:27 am

                Still not a fully signalized intersection – that’s a HAWK signal. I’m talking about intersections where cars see normal traffic signals no matter which of the four directions they come from.

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          • Alex Reed October 29, 2015 at 3:03 pm

            The City actually has a pilot program in to make pedestrian crossings more responsive, so if you call them about other pedestrian crossings, they may be likely to change the timing!

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      • wsbob October 28, 2015 at 7:46 pm

        “…Maybe they should be called “command buttons”. ” John Liu

        That’s a better term for the crosswalk buttons, and more accurate as to how they work. That speaks at least for the two that occur to right at the moment out on Beaverton on both Baseline and Jenkins roads on the Westside trail.

        Also, on Millikan Way just west of Murray Blvd. The flashing lights come on almost immediately after the button has been pushed. Baseline has a posted speed of 40 mph, so having these signal light crossing aids is a huge improvement over not having any help to cross the street between breaks on this streets busy traffic.

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        • Alex Reed October 31, 2015 at 7:57 pm

          Only at crosswalks that are timed to prioritize pedestrians… all of which that I’ve ever seen are at intersections with only a pedestrian crossing (not four-way motor vehicle traffic lights). We can call those “command buttons” but they are WAY outnumbered by the “beg buttons” at four-way intersections and at pedestrian crossings that are still, perplexingly, timed to prioritize motor vehicle traffic.

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  • Spiffy October 28, 2015 at 2:18 pm

    Is our current understanding of cycling behavior based on a slim percentage of the overall cycling population?

    I see this all the time in comments on other sites… people state that we’re building all this infrastructure for the summer commute numbers and then it’s mostly empty in winter…

    I counter by asking if they’d like roads built for the lowest usage… I usually don’t get a response…

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  • rick October 28, 2015 at 2:44 pm

    Not all of the recent concrete stairs around the pdx region have included the wheel step function.

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  • maccoinnich October 28, 2015 at 5:41 pm

    “it might be possible for a city to be too dense for biking” I think this is definitely possible in theory, but we’re a long way from hitting the reality of that in Portland. Copehnagen has a population density of 18,000 people/sq mile, while Portland only has 4,375 people/sq mile. Yes; that include the airport, Forest Park, etc, but even the Pearl was only at 15,671 people/sq mile as of 2010.

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    • gutterbunnybikes October 28, 2015 at 8:35 pm

      And bicycle rates in the Pearl have been falling, while everywhere else in the city center (east and west) have been rising.

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      • maccoinnich October 28, 2015 at 9:17 pm

        It almost as if there’s a correlation between the fact that the City has built almost no bike infrastructure in the Pearl (indeed they even removed a bike lane on Lovejoy) and the low ridership in the Pearl…

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        • gutterbunnybikes October 29, 2015 at 6:30 am

          Or most everything is within a 5 minute walk if you live there.

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          • soren October 29, 2015 at 7:33 am

            Is our current understanding of cycling behavior based on a slim percentage of the overall cycling population?

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  • wsbob October 28, 2015 at 8:03 pm

    Because of the relative speed factor, sidewalks primarily intended for walking, probably don’t need to be as wide as MUP’s, and bike lanes/cycle tracks. A width of 6′ for two way walking works ok. For biking 6′ is barely enough for one way traffic, though people biking often have had to get by with less width.

    Being able to lay some paint down on a road’s existing right of way to create a passable bike lane, is certainly easier and less money than setting up forms and pouring concrete for sidewalks.

    Biggest obstacle to both better biking infrastructure, and better walking infrastructure, may be securing and paying for rights of way where it’s needed to provide room for addition of quality bike lanes and sidewalks. And of course, vision for a future where realistically, increasing percentages of the population may look to walking and biking for getting around.

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    • lop October 29, 2015 at 4:17 pm

      Is that 6′ of through width, or a 6′ sidewalk? Because the sidewalk often has sign/light/utility/catenary poles, bike staples, and other permanent obstacles placed in it. And lots of temporary obstacles like garbage bins and locked bicycles. Is this a commercial street with cafes? Or people stopping to window shop? Or wait for a bus? Is their a curb side travel lane? Does the 6′ start at the curb, or is there a buffer? People don’t like to walk so close to speeding cars. Is there room for two people to walk next to each other without blocking the whole sidewalk if someone behind them wants to walk faster or someone is walking the other way?

      People will squeeze into a small space if that’s all that’s available, but 6′ is far from ideal in many situations.

      Perhaps a bigger obstacle to walking in most of Portland is not that there isn’t a safe place to walk – a real issue in some areas – but that there isn’t anything to walk to. 2-3 miles on a bike isn’t a big deal, but on foot that’s pretty far. Few would bother with a car, transit, or bicycle to go 500 feet. Walkability of a place happens on a smaller scale than bikeability. A neighborhood that’s a mile square or even smaller with lots of destinations could be considered walkable even if the rest of the city is not. But how useful is a short bike path that dead ends and connects to nothing on either end? The stretch of the river greenway in South Waterfront that has a separate path for cyclists and pedestrians doesn’t get many people biking on it, but I see a lot of people walking around whenever I bike through the south waterfront.

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      • wsbob October 29, 2015 at 11:55 pm

        In saying 6′ for sidewalks, I was thinking the walk-able area only, not including the planting strips, and various permanent and temporary objects that clutter and constrict the width of sidewalks. And I said “works ok”, which is not to say ‘great’ for all walking infrastructure. For quiet, low traveled neighborhoods, I’ve walked on 6 sidewalks that work ok with two people passing each other from opposite directions.

        Where more people do, or are hoped to be walking, wider is better. More room to walk means people don’t have to hold a straight line to keep from running into each other. They can wander a bit and relax some. If they can relax while walking, that’s a draw.

        The broad pedestrian boulevards (though bikes are permitted to be ridden on them as well.) through the South Park Blocks past PSU, allows that area to be a wonderful place to walk.

        A contrasting example out in Beaverton, is the Beaverton Town Square parking lot’s central sidewalk serving to allow people to walk without being directly in the lot itself, (at least some of them) between Fred’s and parking spots midway out in the lot, and also, to the south, numerous other restaurants, shops and stores including TJ’s.

        Kind of guessing that sidewalk may be 7′ or 8′ wide, but the design team located the lamp pole bases on a line right down the center of the sidewalk, effectively constricting its usable space at those points by more than half the total width, making this sidewalk awkward and uncomfortable to use if passing people coming from the opposite direction, or even the same direction.

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        • lop October 30, 2015 at 7:07 pm

          >The broad pedestrian boulevards (though bikes are permitted to be ridden on them as well.) through the South Park Blocks past PSU, allows that area to be a wonderful place to walk.

          That can be a very nice place to walk right now. I wonder if that will still be true if the main east west ‘bike road’ turns out to be the park blocks, and lots of bike commuter/recreation traffic ends up routed through the campus.

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          • wsbob October 31, 2015 at 12:29 pm

            I don’t think that riding actually down the sidewalks/mup’s through the center of the Park Blocks, is the thinking behind the idea of promoting a bike route on the Park Blocks potentially used by a lot of bike traffic. At least, I’d hope that’s not the case, because it would be difficult for the park blocks to continue offering visitors to them the relative calm and place to relax and enjoy natural surroundings, if there were to be a lot of bike traffic routed straight down the center of these 100′ wide blocks.

            Ideally, lots of PSU students, profs, and so on would ride bikes to and from the campus, Since a major portion of PSU on both sides, directly adjoins the southern most park blocks, it’s these people that would most likely be using those park blocks to access classroom buildings.

            It would seem to me that a major east-west-south bike route route from NE Broadway, west to the northern- park blocks, then proceeding south along the park blocks (not through them.), would use Park Ave and 9th streets, to the park blocks adjoining the university.

            At that point, the route should go either east to Broadway, or west to 10th and 11th. The city would have to do some things to those streets to have them be functional for people riding that want and need some kind of protection from motor vehicle traffic.

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  • Lenny Anderson
    Lenny Anderson October 29, 2015 at 9:42 am

    Actually, J-walking is the safest way to negotiate streets, either at corners or midblock. One looks both or all ways, assumes nothing, but trusts in one’s own eyes and ears to cross when the coast is clear. In Old Portland you could get a ticket for this and spend a Saturday AM in “traffic school.”
    I recall the “beg button” on N. Channel on Swan Island…it was very responsive, considering that vehicles could be traveling at 60mph or more. I feared at times that PBOT would learn of that (not the speeding, but the button responsiveness) and “fix” it!

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  • Opus the Poet October 29, 2015 at 7:20 pm

    And everybody is ignoring the elephant in the room, making streets about cars is detrimental to both walking and cycling. You want cycling and/i> walking? Either completely tame or completely eliminate motor vehicle traffic.

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  • John Andersen October 31, 2015 at 5:40 am

    There is a big picture, spiritual dimension to walking as a primary means of transportation. It matters.

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  • John Massengale November 3, 2015 at 6:33 am

    I’ve only been to Portland twice, mainly downtown. There was no bike share then, so I’ve never ridden a bike in Portland. In other words, I’m not claiming to be an expert on the state of cycling in Portland.

    What I do know, as an urban designer and street designer, is that a lot of work on bike lanes around the country has been about adding bicycle lanes to transportation corridors. Transportation corridors are first and foremost about traffic flow.

    Many of the transportation corridors where bike lanes have been added are no better for pedestrians after the changes than they were before. Pedestrians want places where people get out of their cars and walk, not non-places where cars flow through, taking most of the space and creating danger. We had 33,000 traffic deaths last year. I don’t know how many of those killed were on bicycles, but obviously a speeding car that hits a cyclist is bad for the cyclist.

    The safest streets are streets with no cars. The second safest streets are streets where cars are going under 20 mph. And streets where cars go under 20 mph are also streets where it’s easy to make places where people want to get out of their cars and walk.

    John Massengale, co-author of Street Design, The Secret to Great Cities and Towns.

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