City will study improvements to notorious section of Dexter between Denny and Mercer

In 2011, the city added a small painted buffer to the bike lanes, but that wasn't enough to prevent more collisions

In 2011, the city added a small painted buffer to the bike lanes, but that wasn’t enough to prevent more collisions

Dexter Ave is among the busiest bike streets in the city. Unfortunately, it has also been the scene of far too many collisions, including a very serious one July 25 and, of course, the devastating collision that took the life of Mike Wang in 2011.

Following Wang’s death, the city painted a couple feet of extra buffer space next to the bike lanes, but the most recent very similar collision just a block further north shows that the extra paint is not enough to address the problem.

After the most recent collision, I was contacted by many readers who expressed concern about the continuing danger and asked if the city planned to do anything to address the problem. I asked SDOT officials, who said they now have plans to look at the section of Dexter Ave between Denny and Mercer next year.

From SDOT spokesperson Rick Sheridan:

SDOT is looking at ways to improve bike safety along Dexter Avenue North. In support of cyclists, we recently installed C-curbs at Dexter and Nickerson to slow merging cars. We also recently made improvements to the two blocks of Dexter Avenue N/Seventh Avenue between John Street and Bell Street to help the street operate more safely and efficiently for everyone. That project reduces the amount of weaving between motorists, transit and cyclists, provides more storage for right turning traffic, and encourages safer and more predictable driving behavior.

To further enhance bike and pedestrian safety along this corridor, in 2014 we will evaluate Dexter from Mercer Street to Denny Way for possible improvements. While driver behavior remains the leading cause of collisions, we want to ensure vulnerable users can safely and comfortably travel on Seattle’s streets.

Inevitably, the question arises about what the city can do to stop people from breaking traffic laws like failure to yield (likely what happened in both collisions, if witness statements to the press are correct). Of course, driver attention is a vital aspect of road safety, but the city can design streets in a way that minimizes the potential dangers and chances for devastating driving mistakes.

While it’s not yet clear what the scope or budget for a Dexter redesign project will look like, we can use this segment of roadway as a great case study to discuss ways streets can be designed to make them easier to drive and safer to biking and walk.

First, here’s the current configuration (well, without the painted buffers, which were not on Google Street View):

Screen Shot 2013-08-05 at 10.31.29 AMDexter is a very wide 90 feet of right of way (including sidewalks) with relatively low motor vehicle traffic levels (and high bicycle traffic levels). Unlike many popular Seattle streets with many different modes competing for little road space, Dexter has too much road space with too few people trying to use it. Excess road space leads to speeding and requires people driving, biking and walking to navigate across multiple lanes to make simple turns and crossings. All these factors add up to an increase in the number of ways a regular, everyday traffic maneuver can end in tragedy. The added speed increases the likelihood that such collisions are severe.

The city cannot easily fix the problem of people breaking road rules or making mistakes, but the city can design roads that reduce the number of chances to make such mistakes and exceed the speed limit.

Using the newly redesigned Streetmix website, I made a few rough thought experiments on ways Dexter could be turned from a dangerous sea of asphalt into an attractive and safe place to bike, walk, drive or catch a bus. I should note that I am a journalist, not a traffic engineer. And there are probably a great many number of ways the street can be improved.

dexter parking2This design includes wide (eight feet) bike lanes protected from general traffic by a line of parked cars. The parked cars have enough space from the bike lane so passengers can open doors without striking someone biking by. The parking also helps to slow passing cars so that most of them would travel closer to the 30 mph speed limit. And, of course, parked cars are a lot cheaper to install than planters or curbs (in fact, they even generate money when the city charges for parking).

The center median would likely be pricey, but it serves two major functions: It makes the street more attractive and it prevents people from using the turn lane as a passing lane. This is especially important at bus stops.

Speaking of which, here’s what a bus stop could look like:

dexter busBasically, the space used for parked cars in the first concept image could be turned into a bus island. This keeps transit moving efficiently, gives people waiting for transit a comfortable space to do so and removes the conflict between people biking and buses pulling to the curb to pick up passengers. This style of bus stop is already in use on the section of Dexter Ave north of Mercer.

dexter turningMost collisions anywhere, but especially on Dexter, occur at intersections. Dexter’s intersections are also complete failures for people trying to cross on foot (again, look at the “current” image above and imagine trying to cross on foot. Yikes!). In this concept image, the space used for parking has been replaced with a low concrete median or pedestrian island of some sort (there would also be a painted crosswalk, not pictured here).

Again, this median serves several functions. First, it assures that parked cars are far enough from the intersection that people turning can clearly see people in the bike lanes. Second, they give people crossing on foot more safe space, effectively reducing their crossing distance from more than 60 feet to about 22 feet. This is huge for all people, but especially for people with mobility issues.

A city that truly prioritizes safety on its roadways would be implementing changes like these as a part of everyday operations. Streets all across the city need this kind of attention, and we are not moving quickly enough to make a dent in the problem. Under Dongho Chang’s leadership, SDOT is becoming an agency that responds more quickly to safety concerns. But it will take a lot more work and a restructured transportation budget if the city will truly achieve its goal of zero traffic deaths by 2030. We really can do this.

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27 Responses to City will study improvements to notorious section of Dexter between Denny and Mercer

  1. David says:

    Drivers turning left from Dexter are likely worried about blocking traffic or getting hit by traffic behind them. Having driven around that area, I personally would never want to come to a complete stop in the left lane of Dexter to yield for a left turn. This creates a feeling of urgency to take the turn, even if it means a cyclist would need to slow down. This creates particularly close calls since bikes travel unexpectedly fast northbound on Dexter (steady downgrade, cyclists can go 20-30mph or even faster).

    The key I think to making Dexter safe is to control the left turns so that traffic can’t turn left at any time. A turn lane would likely help. Adding traffic lights (and limiting where you can turn left to reduce the number of lights) would likely be a good fix.

    • Jonathan says:

      I think David is on to something here – the left turning cars are what I fear most on that street. Perhaps all that is needed is a barrier that prevents lefts except at a few intersections, with added turn lanes there. This is done on busy arterials throughout the city. Yes, it forces drivers to make a u-turn to get to where they want, but it (almost) completely eliminates the risk of crashes from drivers trying to make a quick left in traffic.

      Dexter is not a bad street, and I find it ideal for getting to downtown from North Seattle. But it is wide open in that south section basically for no good reason. A little regulation of the traffic flow could make it much safer.

      • Kevin says:

        The good thing about limiting left turns is that you also cut down car verses car collisions. When cars have to make a u-turn to turn left they often pay more attention and wait for bigger window of opportunity to make the turn.

    • DB says:

      A planted median with left turn pockets would help a lot. Also adding more traffic lights to control the left turns would help.

  2. Herbie says:

    Why not cycle tracks on both sides of the street? You can even make the median wide enough that it can be converted into a left turn lane when necessary.

    http://imgur.com/wcQFJdC

  3. Eli says:

    SDOT’s spokesman really embodies the “old SDOT” mentality of traditional traffic engineers in blaming drivers for collisions. It’s not much different from the blaming people who use handguns for the epidemic of American gun violence.

    In actuality, SDOT is the one actually handing out the handguns by providing streets engineered in ways that make the deadly behavior possible and convenient, and which rely on individual drivers acting nicely.

    If anyone at SDOT earnestly can’t figure how to engineer an arterial street in 2013 so that cyclists aren’t getting killed on it, they’re welcome to join me on my vacation in the Netherlands next month (except I won’t be speaking any English on the trip, so you’d be kinda SOL).

    In fact, I haven’t done the full math, but I’ll bet from Dr. Pucher’s research that there about as many cyclist injuries in the city of Seattle this year as in the *entire country* of The Netherlands.

    • Eli says:

      P.S. re: “In fact, I haven’t done the full math, but I’ll bet from Dr. Pucher’s research that there about as many cyclist injuries in the city of Seattle this year as in the *entire country* of The Netherlands.”

      –> This is totally wrong, sorry. I didn’t control for % of population that bicycles, which throws it off by an order of magnitude alone.

    • Conrad says:

      While I agree that Seattle has some work to do in designing safer streets- I think driver behavior is also a serious problem, maybe even the biggest problem. When I drive, I have no problem avoiding collisions with cyclists and pedestrians. Even on poorly designed streets, because I’m looking for them! There are a lot of drivers out there that flat out don’t see cyclists, or they are impaired, or distracted, or impatient assholes. Drivers need more education on how to share the road. Also, a drivers license should be permanently revoked for negligence leading to a serious “accident”. That might change things.

      • Eli says:

        Unfortunately it might not change things – the only research I’ve read on revoking drivers’ license suggested that a very high rate of people just end up continuing to drive unlicensed. ;-(

    • Andres Salomon says:

      I got that same vibe from SDOT’s statement. Pretty disappointing. It feels very much like a CYA statement; we’ll improve the road, even though it’s obviously not our fault that people keep getting hurt on it. C’mon SDOT, you can do better.

  4. Leif Espelund says:

    Yes, I was thinking of this exact plan as I rode Dexter yesterday. The city could do this on the uber cheap with only paint first and then add curb bulbs, bus bulbs, planted medians, etc. down the road once the painted improvements are shown to be effective.

    Moving the bike lane to inside of a lane of parked cars could be done all the way up Dexter as well to eliminate the almost daily problem of either parking cars or deliver trucks messing up the bike lanes.

  5. Matthew says:

    The improvements at Nickerson and south of Denny are nice, but unless they maintain them, the plastic pylons will be gone within a few weeks, just as the last ones were. One is already missing south of Denny, and one at Nickerson is close to being destroyed. The new curbs are still an improvement, and the new lane alignment at Denny is a big improvement, but I am amazed at how quickly cars and trucks will destroy something that that isn’t steel or concrete.

  6. Brian T says:

    The left turns are really a problem that Tom’s proposed design doesn’t fully address. Narrowing the lanes probably reduces overall speed, and adding the turn lane reduces some of the urgency to making the turn. The combination gives a driver time to slow down without feeling as though they are crossing the Autobahn with Autobahn traffic bearing down on them. That helps. But with the bike lane separated by parked cars, I wonder about visibility of cyclists behind those cars. Calling drivers’ attention to the potential for oncoming cyclists seems critical. Green paint is one thing, but what about a flashing light suspended over the bike lane? Maybe its a flashing bicycle with an arrow pointed down at the bike lane?
    It’s the driver’s responsibility, of course, to be sure there is no oncoming traffic of any kind when they make their turn. But, as Tom and others point out, the facility itself can and should influence behavior: Don’t just hope they look; make them look by drawing their attention to the right things.

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  10. Jeik says:

    I think your re-design is spot-on. I have been going to fitness classes in that area recently and walking 4 blocks along Dexter to take the bus. The center medians would be great for pedestrians to cross such a wide street (or bikes to turn left!). Most importantly, this area has the potential to be the pleasant, urbanized sibling of Aurora. A transformation has really been worked just a few blocks north (to recent to be on Google street view also). With great infrastructure and new development, it would do a lot to promote biking.

  11. Becka says:

    I love this design. Is there a way we could help make this happen?

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