A Pillow of Cement

Cement Pillow at 11th & Clay, in Portland.

“Pillow”-type curb extension at 11th & Clay, in Portland.

Last year, I took a tour of Portland’s Greenways with Seattle Greenways. I learned a great deal about traffic safety, calming and diversion from the Portland’s traffic engineers, although most of it was more relevant to creating good bike infrastructure, rather than transit. There was, however, one idea which struck me as having immediate applicability to transit at certain places in Seattle, namely an experimental variant of a curb bulb using a concrete pillow, as shown above.

SDOT’s website defines a curb bulb as “a radial extension of a sidewalk at a corner or mid-block location used to shorten the crossing distance for pedestrians, provide access to transit, and expand the landscape/furniture and walkable zone … The restricted street width provides a visual cue to motorists, encouraging them to travel more slowly at intersections or midblock locations with curb extensions. Turning speeds at intersections can be reduced with curb extensions” by forcing cars to make sharper turns.

There are some situations, though, where the standard style of curb bulb won’t work, or the existing curb arrangement is not working, because the intersection’s angle is acute or the approaching roads are narrow, and it is frequented by long-wheel-base vehicles like semi-trucks or transit buses. For those vehicles, it may be difficult or impossible for the driver to consistently arrange to make the turn without swinging into oncoming traffic or riding over the curb.

The photo above shows a traffic-calming measure on a pedestrian- and bike-oriented Greenway street which is also used by semi-trucks to access property to the left of the photo. With a normal bulb, these vehicles would routinely be driving all over the curb. The solution PBOT is experimenting with is to fully extend only the straight part of the curb, then install a concrete “pillow” that’s shaped like a speed bump in the radial part of the curb. While drivers of smaller vehicles receive similar cues to slow down as with a normal curb bulb, drivers of longer vehicles can make the turn with only a small bump under the rear axle.

More after the jump.

There are some places in Seattle where buses have similar problems due to the awkward geometry of the street, and a similar treatment might make sense, to improve rider comfort and avoid damage to the curb.

  • MLK & Madison. Buses on southbound Route 8 often ride over the southwest curb at this narrow and acute-angled intersection.
  • 80th St & Wallingford Ave N. This weird intersection has quite a lot of foot traffic, lots of fast car traffic, and the northeast curb has been cut back to only a few feet wide. A pillow-type bulb here might make pedestrians safer, which still allowing the northbound 16 to make the turn.
  • Valley St & 5th Ave N. The southeast corner of this intersection is currently “bulbed out” with paint and an offset stop sign. A full bulb probably wouldn’t work, because of the difficult jog the northbound Routes 3 & 4 must make from 5th to Taylor, but a pillow-type bulb could work.

I know we have lots of bus drivers and riders out in the audience who must know of other places where buses often end up on the curb, or there’s a neighborhood arterial that needs traffic calming, but transit or freight turns might pose a problem. What intersections would you like to see receive this treatment?




Comments

  1. Ian Barrere says:

    Isn’t it the southwest curb of MLK and Madison that a southbound 8 would ride over?

    • Yes, southwest corner, right by the coffee shop. The 8′s roll over that corner all the time, both regular and bendy-buses.

      • Lack Thereof says:

        It’s made worse by the fact that on the MLK facing side, it’s not even driving over a sidewalk. It’s driving over a planting strip, in which a large muddy rut has been worn, packed down to the same level as the street paving. The eastern curb is basically just a speed-bump for the rear axle to get out of the wheelrut and back up on to the paving.

      • I bet this begs a greater question of SDOT actually fixing up the corner for transit use. There have been several improvements there lately (utilities and water, some repaving, a new crosswalk signal), but I feel like this is a no-brainer.

      • Adam Bejan Parast says:

        Another solution is to move the yellow striping over to increase the width of the lane.

      • Lack Thereof says:

        Restriping is not practical unless left turns onto 28th are banned. While it’s not readily observable from Street View, the suicide lane is regularly filled with stopped traffic for the left turn at 28th. And to shift the suicide lane over would require moving the westbound bus stop.

    • Bruce Nourish says:

      Fixed, thanks.

  2. 23rd and John, absolutely ridiculous for buses to navigate in its current design.

  3. I found 65th & 15th nearly impossible to make without contributing to the slow erosion of that curb caused by all the 48′s making that turn day in and day out.

  4. Oh, and this should be obvious, but could we not put large obstacles near any tight corners? This power pole has many preventable accidents notched into it. I walked by it last week and noticed that somebody had taken a softball size chunk out of it with a bus or a truck.

    • Lack Thereof says:

      Those poles have probably been there since the street had unpaved shoulders and no curbs or sidewalks.

      The commonality of things like this is only one of the many reasons Seattle is still mostly 30mph speed limit. If we wanted to go up to a higher speed limit on our arterials like other cities, SDOT would have to embark on an expensive campaign to establish larger clear zones.

      • Bruce Nourish says:

        Maybe we should keep stuff like this then…

      • I don’t know of any city that has a limit higher than 30 on the sort of streets at that intersection (narrow, minor two- or three-lane arterials). And 30 is about right for that type of street, whether or not there are encroaching utility poles.

        We already have higher limits on different types of streets, although in some cases (ahem, Spokane Street Viaduct) they remain way too low.

      • Lack Thereof says:

        Have some patience, the new speed limit for the Spokane Street Viaduct can’t be set until a new traffic study is completed, and that can’t be done until the dust settles and drivers figure out the new lane configuration.

        They think they’ll have the new limit set sometime in the spring, but it will depend on the new accident rates and how often I-5/4th Avenue backups result in standing traffic on the structure. They can’t just slap an arbitrary speed limit on it because it looks like a nice purdy highway. Also don’t get your hopes up for 60 mph or anything. SDOT built the whole project under the assumption that I-5 congestion will back up onto it, and mostly just built it wider so traffic could get to 4th ave when I-5 is hosed.

        (narrow, minor two- or three-lane arterials)

        This is Seattle. All our arterials are narrow. That’s 65th Ave, 4 lanes (2 unstriped), and the major E/W arterial through Roosevelt. As one of the only ways to get across the freeway, traffic volumes on it are massive. And the other direction, 8th? That’s the frontage road that feeds directly from the I-5N offramp to the I-5N onramp. Not exactly insignificant.

      • The downtown core of Bellevue is entirely 30 mph speed limits, save for a couple of more rational 25mph zones. That said, the wide open nature of Bellevue’s roads make it very tempting to drive faster than 30mph which keeps Bellevue’s traffic police well-employed.

      • For the Spokane viaduct, I wouldn’t support 60, but 50 would be perfectly appropriate (as it would on the West Seattle Bridge itself). Every day those 35 signs stay up erodes a bit more of the public’s willingness to take any speed limits seriously.

      • Lack Thereof says:

        I think you’ll be lucky to get anything above 45. There’s no left-side clear zone, the lanes are still only 11′, and there’s a lot of weaving and merging. If the accident rate turns out to be high, it could end up at 40 mph.

        I could see 50 if there were no on/offramps.

      • “wide open nature of Bellevue’s roads make it very tempting to drive faster than 30mph which keeps Bellevue’s traffic police well-employed”

        I’m just reading “Walkable City” by Jeff Speck which says the same thing. Seattle has wider streets than old northeast cities and Portland downtown, but most American cities have wider streets and shoulders because of the tendency to import suburban zoning codes into cities or even to design arterials at freeway standards. The thinking is that by making it safe for overspeeding you’ll lower the accident rate, but Speck says it actually increases the accident rate because the “safe” roadway makes people tend to speed and to not pay attention. So he advocates for making the street no wider than the speed limit requires, and to also consider eliminating “safety features” (separate bike lanes, signs, etc), because streets with fewer features actually have a lower accident rate — because all users are paying closer attention.

  5. Westbound route 44, where 45th Street and Midvale Place diverge. The angle of the curb on the right and the skinniness of the lane between it and the pedestrian island ensure that one out of every two buses mounts the curb.

    I haven’t been on the 44 in the afternoon rush lately, but I worry that cars backing up as far as this single-lane channel could block access to the new bus-only lane.

    • The 44 is the bus I ride most often, and I was happy to see most of the improvements SDOT made recently, but lord that bus-only lane strikes me as one of the stupidest bus improvements I’ve ever seen. Indeed, the backups caused by it regularly extend back to Stone Way, so buses are left sitting in traffic instead of bypassing it. IMO, they shouldn’t’ve extended it east of Woodlawn; the extra lane and TSP west of Woodland Park Ave alone would’ve provided ample relief for the 44.

      I keep hoping for SDOT to acknowledge the error of their ways remove the restriction along Midvale.

  6. I’m not sure this is the best way to handle tight-radius curbs. It blurs the line between street and sidewalk in a way that I’m really not comfortable with as a pedestrian. If we had German or Dutch drivers instead of American drivers, maybe… but we don’t.

    I’d rather just see deeper cuts into the curb for the turn, with the bulb still coming out to narrow the lane further away from the intersection.

    That said, here are a few of my favorite too-sharp curbs (not already mentioned):

    EB Alki onto SB 61st SW. Speaking of horribly placed utility poles…

    EB 100th NE turning right onto SB 5th NE near Northgate. When the 41 uses that routing during the PM peak I feel like I bounce over the curb about every other time.

    NB 44th SW onto EB SW Atlantic and then EB Atlantic onto SB California. Both of these have “dead zones” in the planting strip caused by too many bus tires.

    All three right turns to reach the Broadway 60 terminal.

    The restructure took away one of the worst of all: EB NW 85th onto SB 24th NW. It was rare, but hugely satisfying, to get an artic into the afternoon 18 terminal perfectly straight without clipping the curb.

    • Matthew Johnson says:

      “If we had German or Dutch drivers instead of American drivers, maybe… but we don’t.”

      If we had more German or Dutch style infastructure we’d have more German or Dutch style drivers.

      It’s been proven time and again that signs don’t change people’s driving habits, changing the road does. Hang out around Beacon Hill Station sometime to see how just raising Lander up to be level with the sidewalk causes AMERICAN drivers to slow down and start paying more attention.

      Now that’s not to say we don’t need to make other changes (raise driving age to 18, more rigorous testing, stiffer penalties, etc) just that it’s quicker and easier to change the physical environment than to change people.

      • The difference is one of training, not infrastructure.

        German and Dutch drivers are taught to take driving seriously. American drivers aren’t. That’s a fundamental difference which it would take 50 years to change, even if we completely overhauled new-driver training starting tomorrow.

        A few modifications to the street may change driver behavior a bit around the edges, but won’t make American drivers pay attention to what’s around them rather than the email they’re sending as they drive or their own thoughts.

        I’ve spent plenty of time around Beacon Hill station, and my overwhelming impression is one of drivers who either aggressively threaten or completely ignore people trying to cross Beacon Ave S.

      • Matthew Johnson says:

        Notice I said Lander not Beacon Ave S. Beacon Ave takes the education path, warning drivers of pedestrians, Lander has physical infastructure. The way American drivers treat the two prove my point.

      • Nathanael says:

        Make the street appear narrower and curvier, and drivers slow down.

        Every. Single. Time.

    • As I pedestrian I see that pillow as “car space” not “sidewalk extension”, and ugly like a strip mall with muffler shops and too much parking. If large vehicles need the space to turn, why not just make it part of the street? The white line can stay to guide ordinary cars, but I’m not sure what the bump or white surface is accomplishing. It’s not making me glad the space is there or that I can stand on it, and it’s only shortening my walk by one step. Seattle’s recent pedestrian refuges and sidewalk extensions do more than that.

    • Realistically I don’t think the blurring makes a big difference. People know what’s a street and what’s a sidewalk (just the surface change is a big clue here), and curbs really aren’t much of a safety barrier.

  7. 48-right turn from 65th to 15th. 48-right turn from Greenlake to Wallingford. 355-right turn from 85th to Greenwood. 5-right turn from 42nd to Fremont.

  8. If that thing looks silly now, wait until the paint wears off and the pillow wears down.

    I don’t know, maybe this sort of thing actually works, for some definition of “works”. If so, maybe pillows should be tried on some of the turns to and from the western part of Mercer after it’s rebuilt — it’s a place where heavy and fast car traffic needs to have a cue to slow down before turning across a pedestrian and bike route, but where truck access is often important.

    • Bruce Nourish says:

      Paint will presumably be refreshed on the same schedule other street paintwork. As to wear, it’s 100% concrete and shaped like a speed bump, smoothly rising out of the underlying concrete. I doubt it’ll wear out much faster than the surrounding pavement.

      • If the paint is replaced with the same schedule as other street paintwork, then Al has good reason to scoff. The number of obliterated crosswalk markings in this city is ridiculous—and those are thermoplastic. The stuff on that pillow looks like the traditional paint they use on curbs, which won’t last long at all under the wheels of buses and semis.

    • Lack Thereof says:

      Don’t worry about wear. They put these on the inside of corners at nicer racetracks. Sometimes they even texture them, like at Portland International Raceway. They generally outlast the rest of the surface. The paint does come off (as you can see in turns 9-11, <a href="this point), but it still has quite a distinctive appearance because it’s made of a different material.

      • Surface wear isn’t going to happen, but I wouldn’t be surprised if these things got pounded into the ground. There’s a difference between a 2000 pound race car and a 60,000 pound semi. ;)

  9. Looking at the picture I’m left to wonder if Portland has instituted a helmet law for pedestrians? It wouldn’t be the wackiest thing to come out of Portlandia :=

    • RapidRider says:

      The three helmets I see in this picture are at least two more than are normally worn in Portland at any given time. You can tell they are probably Seattlites.

    • The two on the left are clearly bikers who have stopped to check out the pillow. The one on the right is… well…

  10. Bus turning radii are a major issue, particularly when buses turn off of a diagonal street like Rainier Avenue at a sharp angle. Still, the Portland example appears to be a “mitigation” for the introduction of a pedestrian crosswalk extension bulb from a parking lane rather than a fix to a radius that is too tight. I see tight radii in Seattle as a much bigger bus operations problem than an isolated bulb but it’s a good technique to consider as more bulbs get proposed. The thing that I like most about it is that there is that additional yellow rubberized tile row that doubles as a “rumble strip” for any vehicle that cuts the corner; that should help any concern about paint deterioration as well as make a clear message to drivers that they’ve driven somewhere that they shouldn’t have.

    • Nathanael says:

      They used to solve this problem by putting the buses on tracks, and articulating them if they were so long that they were going to swing over things. Because they were on tracks, they cleared the exact same path every single time. It could be marked on the road. The problem of fishtailing which articulated buses have was solved by putting them on tracks.

      Yes, I’m talking about streetcars. This is still how it’s done in a number of European cities.

      Long buses are dumb. Streetcars were better.

  11. Or move the 16 to Greenlake Drive, Wallingford Ave, and 85th like the 48. Better view, higher speed limit, shorter distance, and only a tiny number of people would have to walk a few more blocks.

    • Speaking of which, the northbound 16′s left turn from 1st Ave. to 80th St. is a frequent source to delays – with no light, the bus can easily be sitting there for 5 minutes or more, waiting for a large enough break in the traffic.

      Is there any way to convince SDOT to install a signal there? Besides helping the bus, it would also be extremely useful to pedestrians and drivers in the area trying to turn onto or cross 80th.

  12. Chase Ballew says:

    I would think that this would be a bad solution for places where busses make right turns. Subjecting passengers to excessive bumping and jostling makes the transit experience worse, not better, which is why rail projects spend a lot of effort and money to produce a smooth ride quality. The idea of intentionally making bus passengers go over bumps would seem, at best, counterproductive. Going over a curb in a bus can be a very unpleasant experience, and it doesn’t much matter if it’s a special mountable curb extension or not. Packages in the back of a truck won’t care, but transit passengers will.

    • Bruce Nourish says:

      “The idea of intentionally making bus passengers go over bumps would seem, at best, counterproductive.”

      The idea is to use this in places where buses are, on a significant percentage of trips, jumping the curb; or in places where, for pedestrian safety, we want to install a curb bulb that might end up being pulverized by buses or trucks. The idea is not to make people go over bumps, but in cases where they’re probably going to get bumped anyway, to make them go over a smaller bump that doesn’t wreck the curb.

  13. Tim Willis says:

    Roy and Queen Anne Ave, where the 2, 13 and 29 turn up Queen Anne Ave.

  14. Jim Cusick says:

    “While drivers of smaller vehicles receive similar cues to slow down as with a normal curb bulb, drivers of longer vehicles can make the turn with only a small bump under the rear axle.”

    Plus it’s really a hassle for truckers, what with all those pedestrians stuck between the trailer wheels.

    Pedestrian areas will always be encroached upon if there isn’t a ‘hard divide’ between auto and pedestrian areas.

    For those of you who venture to the suburbs, you can see any neighborhood that has those ‘soft gutters’ with rolled edges up to the sidewalk height, will invariably have a car parked on the sidewalk. Even older in-city neighborhoods where the infrastructure has sagged will invite that encroachment.

    Better to keep them separate.

    And personally I think that should include bicycle infrastructure, too.

Trackbacks

  1. [...] (author unknown) Cement Pillow at 11th & Clay, in Portland. “Pillow”-type curb extension at 11th & Clay, [...]

Sign in or create an account to save your credentials and make commenting faster.



You may want to read our comment policy.