To Make Streets Safer, Seattle May Get Rid of Traffic Signals

In Philadelphia, crashes declined 24 percent after stop signs replaced signals at 200 intersections. Image: Google Street View
In Philadelphia, crashes declined 24 percent after stop signs replaced signals at 200 intersections. Image: Google Street View

Here’s an intriguing idea to make city streets safer. Seattle is reviewing 10 intersections to see if traffic signals should be replaced with four-way stops.

Signalized intersections carry special risks. Drivers often accelerate into the intersection during the yellow phase to “beat the light,” for instance, leading to high-speed crashes. The Federal Highway Administration warns that improperly placed signals may “significantly increase collisions” [PDF, page 9-35].

One alternative to signals is a roundabout, in which traffic entering the intersection is deflected by a center island, and incoming drivers yield to traffic in the circle. One study cited by the FHWA found that crashes with injuries declined 78 percent at nine intersections after signals were replaced with roundabouts.

Another option is the basic four-way stop, which is more common in America.

In a study of 200 signalized intersections in Philadelphia where one-way streets converged, replacing the signals with stop signs led to a 24 percent reduction in crashes, according to FHWA. Crashes involving pedestrians fell 17 percent, and nighttime collisions involving pedestrians declined 46 percent.

Even though signals cost more to install and operate than stop signs, many intersections in American cities are signalized when public safety would be better served by stop signs or roundabouts.

Seattle is seeking suggestions about which signalized intersections should studied for conversion to four-way stops and will evaluate whether to proceed on a case-by-case basis. If the pilot is successful the program may be continued, said city traffic engineer Dongho Chang.

  • mckillio

    Here in Denver we definitely have way too many traffic signals.

  • Joe R.

    NYC needs to do this on a wholesale basis. Easily 90% of our 12,000+ signalized intersections don’t need to be signalized. Roundabouts or uncontrolled intersections should replace the majority of them. Both are self-enforcing in that you crash if you don’t proceed through at reasonable speeds.

  • Four way stop signs are the worst for traffic collisions. I experience more near misses from cars ignoring stop signs and failing to yield at four way stop than I ever experience at an intersection with a traffic signal.

  • Miles Bader

    Ugh, having lived in the UK, where they fetishize roundabouts beyond all reason, I learned to hate them.

    I only walked and biked there, so I can’t speak about cars, but my general feeling was that they were OK as a bicyclist (it was even kind of fun swooping around in a circle), but a disaster as a pedestrian.

    Really big roundabouts are a little better, but they take insane amounts of space, and so are really only practical in a few cases. They also tend to push pedestrian paths all over the place, so end up feeling like a giant detour.

    “Mini roundabouts”, which take space more on the same order as an ordinary intersection, are really freaking scary as a pedestrian, because cars more or less never stop, and because the car that might hit you can seemingly come from any direction, there’s less sense of organization you can use to structure your avoidance of being killed….

    But of course this decision in Seattle won’t be made from a pedestrian point of view, it will be made by drivers listing to a driver-centric electorate.

  • Roo_Beav

    What’s with the stop sign fetish? Almost nobody will actually stop at an intersection when there’s no other traffic around. Why can’t yield signs be used far more often? For the least busy of intersections, why not go uncontrolled? Those have a traffic calming effect because they are self-enforcing.

  • ahwr

    Seattle has some mini roundabouts.

    https://goo.gl/maps/kV1fexr7qWC2

    Some are only paint.

    https://goo.gl/maps/94D3xWma3bp

  • Bernard Finucane

    Not a fan of four way stops at all. A better idea is to set the right of way in one direction and put stop signs or yield signs in the other.

    I guess four way stops are intended to slow traffic, but a better idea would be curb extensions, or flex posts if they are cheaper.

  • Baloo Uriza

    Instead of stops, let’s try yield signs. Granted, the northwest has a hard time with the whole yield concept…

  • Michel S

    This is actually a terrible compromise. There’s a two-way stop in my neighborhood, and if you’re trying to cross the street on foot cars with the right-of-way will speed past the intersection and won’t slow down to let you pass, and half the time parked cars obstruct the view so it makes crossing even more dangerous. Better to just make all cars stop on the off-chance a pedestrian needs to cross.

  • Michel S

    “In Philadelphia, crashes declined 24 percent after stop signs replaced signals at 200 intersections.”
    YAY! We did something right!

  • Bernard Finucane

    They speed past because the intersections are too wide. The parked cars obstruct the view because there are no curb extensions at the intersections preventing it. The streets are also dangerous to pedestrians because the crossing length is too big.

    https://www.google.de/maps/@51.2441374,6.8075616,3a,50.1y,251.49h,70.62t/data=!3m6!1e1!3m4!1sAS5o1kNYMMTQIAz5z_sRjQ!2e0!7i13312!8i6656!6m1!1e1

  • Michel S

    Ok, so I will amend my statement above to read:
    In the absence of curb extensions that reduce the crossing distance and prevent parked cars from obstructing views, two-way stops are a terrible compromise. Until such protections are in place, it is better to just make all cars stop.”

  • c2check

    A lot of lower-volume intersections in Germany have no stop signs or signals at all; it’s implied that every such leg must yield to traffic on the right. That sure teaches folks they have slow down and pay attention at intersections 😉

  • c2check

    A lot of lower-volume intersections in Germany have no stop signs or signals at all; it’s implied that every such leg must yield to traffic on the right. That sure teaches folks they have slow down and pay attention at intersections 😉

  • J

    To reduce injuries and deaths at intersections, it seems clear that we must reduce vehicle speeds as they approach intersections, increase visibility of both vehicles and people of foot/bike, and reduce pedestrian exposure to cars. To do this, a combination of curb extensions and traffic calming on all intersection approaches would seem to be ideal. Without traffic calming measures, I worry that drivers moving in the direction with the right of way, as you suggest, may actually drive faster, increasing the danger for everyone.

  • Michel S

    “Without traffic calming measures, I worry that drivers moving in the direction with the right of way, as you suggest, may actually drive faster, increasing the danger for everyone.”
    Correct. This is exactly what they do in my neighborhood.

  • Tim Yogerst

    Meanwhile, smog from accelerating emissions, asbestos dust from brake pad wear, and driver road-rage incidents are all increased by over 50% above previous levels.

  • You contradict yourself, saying “worst for traffic collisions” and then “more near misses.” A near miss means someone was paying attention and took action to avoid a collision. This is a good thing.

  • Near misses are iust that; a near tragedy where the differences between life and death were a matter of inches or fractions of a second. Because 4-way stops are more ambiguous by their very nature, it’s not surprising that more collisions happen on them.

  • Walter Crunch

    Ditch stop signs. Yield signs are the way to go..or roundabouts. Or non signalized intersections all together.

  • Walter Crunch

    Asbestos was taken out of brake pads long ago.

  • Jason

    It also incentivizes drivers on the non-right-of-way street to do stupid shit because you can often sit for a long time waiting for an opening.

    On the extreme end of that, look at LA, where there’s tons of intersections where it’s legal to proceed straight across six-eight lanes of traffic and to make left turns, but there’s a traffic light a block to the left and a traffic light a block to the right. (Why it’s legal to do anything other than turn right at these intersections is beyond me.) The traffic on the highway-like boulevards moves at high speed with very intermittent breaks; meanwhile you can sit for a long time waiting for an opening. It induces drivers to eventually gamble on really stupid maneuvers that are unsafe for everyone.

    And the cherry on top of that shit sundae of urban design is that at a lot of these intersections the non-right-of-way drivers can’t even fucking see oncoming traffic without completely obstructing the crosswalk because of how close to the corners parking is allowed.

  • Jason

    You still haven’t explained how a near-miss is a collision.

    Regardless, even if we ignore this absurd suggestion that near-misses somehow being equivalent to collisions, there’s still the crucial point that the collisions would be happening at significantly slower speeds because by the very nature of what STOP signs do.

  • Jason

    Uh…what? Late at night when nobody’s around, people may be more inclined to do “rolling stops”, but I think it’s pretty rare for people to completely blow through stop signs. Which is still having the desired effect–getting people to slow the fuck down. Admittedly, placing stop signs at every corner doesn’t stop a lot of people from gunning it out of every stop sign only to have to slam their brakes at the next stop sign, intersection after intersection.

  • Dangerous conditions that cause near misses also cause collisions. 4-way stop signs, in my experience are far more dangerous than traffic signals. Near-misses are a symptom of a problem not a sign that things are working.

    Four way stops create ambiguity which drastically increases risk because people will always make mistakes. The bean-counter argument that 4-way stops should be safer ignores the reality that the overwhelming majority of people do not actually stop at them most of the time when they would if there was an actual red light.

  • crazyvag

    San Francisco is converting some 4-way stop signs on routes where buses and trains run to speed up transit. Bus/train gets an early / longer light when approaching. The intersections in this article either don’t have buses on them or buses that don’t need to be sped up. Anyway, just another perspective.

  • Baloo Uriza

    I definitely recognize Sepulveda Boulevard as what you’re referencing. But the nice thing about allowing lefts and through movements is that it’s typically safe to do an Oklahoma expressway left or through on it if you’re on a bicycle (cross one side, stop in the median, cross or join the other side).

  • Baloo Uriza

    Your first example is not a mini roundabout since it’s actually a nontraversable median there. The second one is a mini roundabout because you can drive over it.

  • Bernard Finucane

    Makes sense.

  • socaldano

    Guessing… do a little research, and you will find that stop signs and traffic signals are to improve the flow of traffic. When a four way stop is justified, they are great, when they are not justified they are in violation of the State and US engineering standard, state and federal law, and cause all kinds of problems… Many of the stop signs I have seen in Florida are justified, many of the stop signs in St Louis are ILlegal and violate the engineering codes, many of the stop signs in Los Angeles or San Diego are legal, but City of Los Angeles loves to put up illegal stop signs…like at the entrance to a traffic circle

  • sulablue

    Honestly. People suck at handling 4 way stops. They just do. They either don’t know the right way to handle it or they try to “be polite” and end up causing a mess. Just don’t. Please.

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