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Yeah, those silly “road diets”.  According to WikiPedia, road diets are:

A road diet, also called a lane reduction or road rechannelization, is a technique in transportation planning whereby the number of travel lanes and/or effective width of the road is reduced in order to achieve systemic improvements.

Actually road diets are Beyond Stupid.  Just as much as putting more lanes on I-5… Recently the Washington Policy Center’s Bob Pishue punded away:

As Sound Transit officials prepare to take over the center lanes of I-90, their newest online advertisement asks the question, “What’s to do when we’re running out of roads?”(Their edited clip was originally from a video promoting highway building.) Unsurprisingly, their answer is to build light rail.

Yet they completely ignore the fact that public officials have continually pushed to make the public “run out” of roads. State officials are reducing the six-lane viaduct to a four-lane tunnel, guaranteeing traffic snarls around Seattle. Sound Transit is taking away the center lanes of I-90 for light rail, which the State Department of Transportation estimates will increase traffic congestion despite restriping the outer lanes. Seattle’s leaders have added to gridlock by handing over roads around the city to streetcars, transit, and bike paths. Instead of providing more general purpose access on the new SR-520 Bridge for the traveling public, state lawmakers opted instead for a new bike path and HOV/transit lanes.

Getting around is already tough out there, but it gets even tougher when public officials take away road access then say we are “running out” of capacity.

According to the aforementioned WikiPedia article, road dieting also is a problem for buses:

Road diets can negatively affect the speed and reliability of transit service operating on the roadway, particularly if bus stops are located in pullouts and traffic queues delay buses attempting to re-enter traffic. Constructing bus bulbs can mitigate these effects though this feature results in delays for other vehicles.

So what do we do?  Well then:

  1. New road lanes have limited effectiveness
  2. Use better the roads we have – and if road dieting is about safety, then reduce the speed limit
  3. Never forget real congestion relief is mass transit
  4. Require new facilities like museums & airport terminals have baked in transit structural & scheduled capability.

27 Replies to “North by Northwest View 16: Quit With the “Road Diets”…”

  1. Pishue is mostly wrong. Here’s why:

    State officials are reducing the six-lane viaduct to a four-lane tunnel, guaranteeing traffic snarls around Seattle.

    Leading off by saying that your argument is proved because the viaduct tunnel is seriously flawed is equivalent to a declaration that water makes things wet. The viaduct tunnel is a broken project all by itself.

    Sound Transit is taking away the center lanes of I-90 for light rail, which the State Department of Transportation estimates will increase traffic congestion despite restriping the outer lanes.

    The FEIS directly contradicts this statement. In the summary, on page 61 (internal page number S-36), WSDOT specifically says that a person traveling alone in the general purpose lanes is estimated to see a reduction of travel time by 8.9 minutes.

    Seattle’s leaders have added to gridlock by handing over roads around the city to streetcars, transit, and bike paths.

    Yes, because these modes are either more efficient per-person (you can run a lot more people in one bus than in the same space occupied by cars) or make a mode of transportation we in the city have deemed worthy–bicycles–safer and more comfortable to use. That’s limiting transportation in the sense that limiting my intake of milkshakes is a “shake diet.” It’s good for me and I like the results, though, man, those milkshakes were good when I had them.

    Instead of providing more general purpose access on the new SR-520 Bridge for the traveling public, state lawmakers opted instead for a new bike path and HOV/transit lanes.

    Right, because a bike path takes up relatively little space (look at the vast amounts of waste space on the IH-90 bridge from the bike path; wait, there is barely any) and, again, HOV and transit lanes allow for more throughput in the same space.

    For what it’s worth, none of these is related to a road diet, as you defined from your Wikipedia cite. Road diets do work, at least how Seattle does them. If we turn to NE 125th St, SDOT traffic studies found that after two years, crashes are down, speeding is down, yet traffic volume is up. Amazingly, the same results happened on NE 75th after its road diet, including the increased traffic throughput. Oh, and a few years back on Nickerson St.

    Taking a four-lane road with no turn lane and “reducing” it to three lanes with one travel lane each way and a left turn in the middle is provably better for in-city, mid-tier arterials. Putting a left-turn lane in place lets people get the heck out of the way. Travel times are estimated to be about the same for regular cars after 23rd Ave is reconstructed and “dieted,” even with the maligned bus pull-outs (a lot of near-misses happen on 23rd from people trying to swerve around a route 48 bus stopping or people trying to beat the bus at a light).

    1. lakecityrider (Wes), that’s a great comment. I like the fact you researched your response. If we can provide congestion relief, let’s do it. But the goals must be congestion relief and safety.

      1. Then I’m not sure why you’re implying that you agree with Pishue. His posts always seem to miss the subtleties of real life and simply concentrate on “if it ain’t roads, I ain’t interested.” Yes, if SDOT came along to chisel up Northgate Way and stick “street end” signs in the middle of its biggest sections, that would be reducing capacity. A legitimate debate can be had over how Broadway has seen the integration of the cycle track and streetcar tracks but once the streetcar is running, I think it will improve.

        In every single case, SDOT has done studies that show that moving people–and that’s the important part–into, out of, and through an area will improve overall after a project is completed. Their estimates may turn out to be wrong, which is disappointing but also a subtlety of real life, and the problem should be fixed if it turns out to be flawed. We need to have a fundamental shift from thinking “how will cars handle this” to “how can we move people.” I choose to live inside the city limits of Seattle because, among other policy beliefs, the city government and my fellow residents are choosing to emphasize the latter instead of the former. We have the data and are developing the experience to show that we can do it.

      2. Wes;

        Two thoughts:

        1) I just find it odd we’re taking away road lanes which causes congestion and then complaining about it.

        2) I am 100% of the view that congestion relief = moving people, not cars. How many people really want to slap more lanes on I-5 from Seattle to Everett versus those that will demand environmental impact studies, litigate those studies, judicial review of eminent domain, engage in peaceful (and I have no doubt they will be peaceful) marches up & down the Puget Sound with long banners about the harm to Mother Earth, et al.

        Frankly I think it’s important we ask ourselves are we the enemy when it comes to fighting congestion or are we humans going to find the most cost-effective efficient means to move people from work to home & around folks’ communities?

      3. http://seattlegreenways.org/blog/2015/02/15/save-lives-keep-moving/

        Pishue completely ignores the value of public safety in his piece. The results are pretty clear in the cases I’ve linked: a properly instituted road diet can make a dangerous street much safer without imposing a significant time penalty on drivers.

        I hope the coming plan for Rainier Avenue can deliver the same results without making the adjacent arterials more dangerous.

      4. I just find it odd we’re taking away road lanes which causes congestion

        Objection, assumes facts not within evidence. The links I cited prove, with actual data, that “taking away” lanes–where “taking away” is defined as reducing the numerical count of the lanes striped on the surface of the pavement–does the exact opposite of causing congestion. It improves street throughput, increases safety, and even lets the same pavement carry more people and vehicles.

        There is only one major road project that I know of that can be said to have reduced vehicle capacity in Seattle: the reconfiguration of Broadway for the streetcar. However, much like what is proposed for 1st Ave with the Central City Connector, the capacity for moving people is increased (the debate about the Broadway streetcar and whether it should exist is, in my mind, separate).

        Pishue is wrong. Building more roads is not how we will solve congestion. Convincing people to get their butts out of SOVs and into more efficient modes of transportation–by making those modes comfortable, reliable, and interconnected all at the same time–is how we will do it.

      5. LakeCityRider (Wes);

        Building more roads is not how we will solve congestion. Convincing people to get their butts out of SOVs and into more efficient modes of transportation–by making those modes comfortable, reliable, and interconnected all at the same time–is how we will do it.

        Is why I’m here at the end of the day. Not just do I want transit to serve more destinations but also… congestion relief.

  2. Road diets are necessary in some situations, especially in urban environments. Rainier Avenue desperately needs one, seeing as drivers have no respect for speed limits and occasionally crash into buildings along “their” speedway.

    1. Bruce, on this, I’m willing to listen. I have no respect for drivers who diss speed limits. There might be a way to engineer a speed reduction….

      1. Not backing the road diet plan….. ;-)

        Nice try.

        Happy to challenge progressive orthodoxy.

      2. It’s not “progressive orthodoxy”; it’s basic traffic engineering.

        Making people drive more carefully by changing the physical design of the street is more effective than putting up signs and hoping people will abide then trying to enforce those signs with police and cameras. The results of Seattle’s road safety redesigns speak for themselves.

        Props for thinking the goal is to “move people, not cars” which is against what the WPC seems to think. Therefore it follows that reallocating road space to make it safer for people to walk and bike, and make transit more reliable, would advance us towards that goal. If that’s what you truly think then I don’t understand your blanket dismissal of road diets at all.

  3. Bus bulbation now! Bus bulbation tomorra! Bus bulbation fohevah!”

    Thanx and a tip of the Hatlo Hat to George Corley Wallace, Governor of Al-A-Bama!

  4. No, simply reducing the speed limit is almost useless. People will drive whatever speed they feel comfortable driving given the design of the street.

    1. I’m of the view a good speed limit works.

      I’m also a proponent of considering bus-only lanes.

      1. >>I’m of the view a good speed limit works.<<

        Well, you're wrong. It doesn't work. You can find streets where 80% of the drivers are speeding (and not just by 2-3 MPH) because the design of the road encourages people to drive faster than the legal limit.

      2. Here’s an example showing that speed limits don’t work. Only physical design works.

        http://www.streetsblog.org/2013/03/18/dot-speeding-the-leading-cause-of-nyc-traffic-deaths-in-2012/

        “DOT released a map illustrating 100 locations where 75 percent or more drivers were speeding within a quarter-mile of schools.”

        Pedestrian Injuries Down Nearly 30% After 4th Ave Road Diet in Sunset Park:

        http://www.streetsblog.org/2014/05/21/speeding-ped-injuries-drop-sharply-after-4th-avenue-road-diet-in-sunset-park/

        “with a report on how the redesign has affected safety. The results are positive: More people are walking on Fourth Avenue, while speeding, crashes, and pedestrian injuries are all down significantly”

        TA: 88% of Brooklyn Drivers Are Speeding, And Almost None Get Tickets

        http://www.streetsblog.org/2013/06/17/ta-88-of-brooklyn-drivers-are-speeding-with-little-nypd-enforcement/

        “Transportation Alternatives observed nearly nine in ten Brooklyn motorists breaking the speed limit while compiling data for its new report on dangerous driving [PDF], but enforcement from NYPD remains almost non-existent. In fact, TA says it clocked more drivers speeding in 12 hours than NYPD ticketed in all of 2011. That’s why speed cameras are necessary for city streets.”

        People won’t even notice a 25MPH speed limit if the design of the street makes them comfortable driving 35-40 MPH. This is not what I “believe”. This is what has shown to be true time and time again.

    2. When the speed limit is noticably lower than the speed that the design of the road encourages people to drive, you have one of two things. Either a speed limit that nobody obeys and is never enforced. Or you have, what is called, a “speed trap”, which creates the appearance that the real goal is not public safety, but to increase ticket revenue.

      In the case of a road diet, the only drivers that are adversely affected are those poor souls who want to go 50 mph in a 30 mph zone, but are stuck behind another driver who is actually going the speed limit. In which case, I would argue that the road diet is doing its job.

      1. I just think there’s a hypocrisy in road dieting major aeterials. You guys are winning me over slowly at a municipal level, but at the state & federal road level… not so much.

    3. Streets have been getting ever wider since the 1960s as engineers tried to ensure that drunk drivers wouldn’t run off the road and kill kids, and that two fire trucks could do a U-turn simultaneously. The result is streets as wide as freeways but signed 30 or 35 mph, and people don’t believe the signs because they sound ridiculous.

      It’s less bad here than other parts of the US because Seattle’s streets are old and the suburbs have drunk only some of the cool-aid. Seattle’s era was more of 4-lane arterials. The engineers have since determined that two general-purpose lanes and a left-turn lane gives more thoroughput and much more safety, because cars aren’t constantly changing lanes to turn left or right, which slows down all cars and leads to accidents. If they’re turning right, they simply turn right or use a pocket lane. If they’re turning left, they use the left-turn lane which is emptier than the regular lanes. This all leaves the fourth lane’s space unused, so it can be converted to two bike lanes, one transit lane, widened sidewalks, bioswatches, or whatever else. If you also take a parking row, then you can fit two transit lanes or a cycletrack. This is not so much a war on cars as a re-equalization after everything except cars were made second-class citizens.

      Bus bulbs allow buses to stop in the lane, which make bus stops faster like train stops. That forces cars to stop behind the buses because there’s no longer a passing lane or off-street bus stop. That irritates drivers. But the bus may be carrying fifty people, which is equivalent to fifty cars. Any street that has a road diet and a lot of buses probably has high ridership; otherwise the road diet wouldn’t have happened or the buses wouldn’t be there or wouldn’t stop as much.

      1. Great comment Mike. I really love bus bulbs… maybe I should ask my Friday afternoon interview subject in his/her mayoral office about putting some on his/her speedway ;-).

  5. A couple of points:

    First, the current viaduct only has 4 through lanes so there is no capacity reduction. In any case such a reduction is irrelevant as by WSDOT’s own estimates the amount of through traffic is far less than the capacity of 4 lanes. The vast majority of cars on 99 are going to/from destinations that no longer will have exits once the current viaduct closes.

    Second road diets can move more people and reduce traffic congestion. Reducing lane changing and giving drivers turn pockets actually helps traffic flow more freely. Bus and HOV lanes simply move more people than GP lanes. People get cranky about losing on-street parking, but there is no right to subsidized parking in road right of ways.

    1. Chris,

      I’m beginning to believe road diets work to limited degrees at a urban level. It’s when we start doing it to major highways and the like I still have a problem… it’s not smart to create congestion by road dieting highways.

      That said, I doubt seriously I’ve ever seen this kind of thoughtful, deliberate commentary on any of my STB Page 2 posts from all of you. :-)

      1. Not sure where there are examples of highway road diets. In any case if said diet swaps a GP lane for an HOV lane the highway should move more people as the occupancy in the HOV lane is higher.

        Similar effects might be seen if re-channelizing reduces lane changes even if the total lanes are reduced.

      2. Maybe I took this story the wrong way then. I sure am reading reams of research & anecdotal stories correcting me… and I like those kinda comments.

        I’m a big fan of Bus Rapid Transit/BRT after all my Swift rides!

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