Tag Archives: traffic signal


The cyclist’s comment on this Youtube video: “This is why turn signals are important. Had she used a turn signal, I would have stayed back and let her turn. But because she didn’t use one, I assumed she was going straight.”

Let’s take a look into the situation.

The car was initially stopped, second in line at a traffic light. Then the light turned green. The cyclist was approaching in the separated bikeway from the car’s right rear, off to the side. As the motorist initiated her turn, the cyclist wouldn’t be visible in the motorist’s passenger-side rear-view mirror. The motorist would have had to turn her head sharply to the right to see the cyclist, but she needed to look ahead to steer and avoid other potential conflicts. Yes, she should have used her turn signal, but again, she was supposed to yield to the cyclist, not the other way around, and the location of the bikeway made it easy for her not to notice the cyclist.

What are solutions to this problem?

* Well, certainly, drivers should use their signals.

* Bicyclists need to be aware of these conflict situations, and it’s best not to make assumptions.

* Bikeways like this create the appearance of safety because of “fear to the rear” but in urban and suburban areas, most car-bike crashes are due to crossing and turning conflicts, including the one shown in the video, the classic “right hook” –and also the “left cross” (car turns left into the path of an oncoming cyclist). This is a two-way bikeway on one side of a street and so it placed the cyclist farther outside the view of the turning motorist, and can also lead to “Left hooks” and “right crosses”. Germany no longer recommends two-way bikeways like this, as the safety record has proved to be especially poor.

* To avoid these conflicts, the bikeway needs an exclusive signal phase when other traffic doesn’t turn across it. But that will result in more delay for bicyclists and motorists alike. This bikeway also crosses driveways where the barrier is interrupted.

* A bikeway in a corridor separate from streets, a bike route on lightly-used streets, ordinary striped bike lanes or wide outside lanes avoid the problems with a separated bikeway.

The location, in Seattle, Washington, USA.

Alice Swanson fatality, a right hook

Here is the intersection in Washington, DC, where cyclist Alice Swanson was killed by a right-turning garbage truck.

The Street View is from 2009, as close as Google gets to the year of the crash (2008). The big cross street is Connecticut Avenue. The little one before it is 20th Street NW. My recollection is that the garbage truck turned right into 20th Street, and Swanson probably assumed she could pass it safely because it would turn right onto Connecticut Avenue and the traffic signal was red. If you open the Street View in Google Maps and click on the clock at the upper left, you can go to Street Views from different times and see the intersection without a bike lane (2007) and with green paint (2014). The dashed bike lane stripes indicate that motorists are supposed to merge into the bike lane, but many do not and it may not even be possible with a large truck. Note also that parking extends close to the intersection — the last 20 feet or so are no parking, with a fire hydrant.

Boston expert design

Here’s a video of the intersection of Commonwealth Avenue and St. Mary Street, Boston, Massachusetts, USA, an example of the design expertise which earns Boston its place with the League of American Bicyclists as a Bicycle Friendly City.

The video is from 2013. As of 2016, one change has been made: the zigzag in the bike lane has been replaced by a diagonal transition.

The idea that cyclists should turn across in front of multiple lines of motor vehicles to change lane position is not unique to this location. Here’s another example, and it is by no means the only other one:

I have a blog post in connection with that video too.

Berri at Cherrier, Montreal

Gerald Fittipaldi, who is on an e-mail list with me, has posted a video on Flickr of cyclists traveling through an intersection where a two-way bikeway turns from one street to the other.

Clicking on the link above, or the still image below, will bring up the video on your computer screen.

Bicyclists at the intersection of Rue Cherrier and Rue Berri, Montreal

Video of Montreal intersection

Mr. Fittipaldi has described the intersection:

Below is a video of a protected intersection for bicyclists in Montreal. This is at the crossroads of two heavily used 2-way cycle tracks. Metal pylons are used to form a large protective space for cyclists queueing to make a left turn.

This is the intersection of Rue Cherrier and Rue Berri in Montreal. I’ve been there. The “protective space” operates as a two-stage left-turn queuing box for left-turning traffic, but it also serves right-turning traffic traveling in the opposite direction.
Bikeways which are separated from the travel lanes of the street are commonly referred to as “protected,” and Mr. Fittipaldi refers to Berri and Cherrier as a “protected intersection.”
The term “protected” is used in traffic engineering to refer to a movement during which conflicting movements are prohibited, however, at this intersection, bicyclists crossing Rue Berri are exposed to conflicts with traffic turning right and left from Cherrier. At the start of the video, bicyclists get a few seconds of advanced green, but otherwise there is no separate signal phase or turn prohibition.
The bikeway across Cherrier does get a protected green while southbound motor traffic on Berri waiting to right or onto the frontage road is held back by a red light as shown in the video, and similarly for northbound traffic, by a left-turn signal: see Google Street View with the sign “attendre la flèche pour virer à gauche” (Wait for the arrow to turn left). I’ve included an image from the street view below. The “protected space” is visible in the background

The sign reads, in French, "ait for the arrow to turn left."

The sign reads, in French, “wait for the arrow to turn left.”

Because of the two-way bicycle traffic in narrow corridors on one side of the street, unconventional encounters between bicyclists are common. For some reason, flickr’s time indication in the video runs from high to low. At 00.46, near the start, the video shows bicyclists headed toward the camera passing to the right of another who is headed away from the camera. Another bicyclist may be seen riding against traffic on the far side of the intersection. Later, at 00:28, a large number approach in the crosswalk rather than in the bikeway. Several bicyclists merge left around the waiting area to continue on Cherrier. At 00:12, one bicyclist ignores the waiting area, which is already crowded, timing his left turn to the signal change.

Thanks to the time of day at which it was shot, the video shows all but one bicyclist headed westbound on Cherrier and turning left onto Berri — for which the area inside the pylons serves as a conventional two-stage left-turn queuing box. But, because both streets have two-way one-side-of-the-street bikeways, right turns using the installation are made by going around the outside of the intersection clockwise, from the left side of Berri to the left side of Cherrier. This is very time-consuming compared with a conventional right-turn. as shown at 3:00 and following in my own video.

For other movements as well, signal compliance is poor, and some bicyclists take unconventional shortcuts. That is the case with one bicyclist already mentioned, and with both bicyclists in this Google Street view:

Two bicyclists ignore the designated route at Berri and Cherrier

Two bicyclists ignore the designated route at Berri and Cherrier

— also with the bicyclist at the right here, on Cherrier just east of Berri.

Bicyclist riding opposite traffic on Rue Cherrier

Bicyclist riding opposite traffic on Rue Cherrier

Is the NACTO Guide a Design Manual?

In cities around the USA, politicians, under pressure from populist bicycling advocates, have pointed to the NACTO (National Association of City Transportation Officials) Urban Street Design Guide and directed their engineering staff to install treatments which it describes.

I’ll say right here that some of the treatments which the NACTO guide describes deserve attention and inclusion in national design standards — though their presentation in the NACTO Guide typically is flawed, inconsistent and incomplete. Why some deserving treatments are not included in the national design standards is a story for another time.

Other NACTO treatments are so troublesome that they are not widely applicable.

Engineers unfamiliar with bicycling issues may take NACTO designs at face value; other engineers may throw up their hands and comply, faced with the threat of losing their employment. Several engineers who have extensive background and expertise in design for bicycling have resigned, been fired or been demoted when they would not accept the NACTO designs.

What leads to these problems? To put it simply, the NACTO guide isn’t a design manual. It is a smorgasbord of design treatments formatted — right down to digitally-generated loose-leaf binder holes on what are, after all, Web pages — to look like a design manual to politicians and the general public. Bicycle manufacturers funded it to promote street designs which they expect will lead to greater bicycle sales. It lacks the vetting necessary for consistency and accuracy. Its purpose is to generate political pressure to apply the treatments it describes. It is weak on specifics: rife with errors, and with omissions even in describing the treatments it covers.

If I described all of my specific  concerns with the NACTO Guide, I’d be writing a book, so for now let’s just look at a two-page spread of the NACTO Guide, the pages about two-stage turn queuing boxes (2STQBs, for short).

Maybe by now you are inclined to think of me  as a naysayer, so, let me get down to some specifics to dispel that impression. I have had information about two-stage turn queuing boxes online for years, I think that they are a useful treatment, and I use two-stage turns: when I realize that I have reached the street where I need to turn left, but hadn’t merged to turn; when traffic is heavy and fast and I haven’t found an opportunity to merge; when ordinary left turns are prohibited. My favorite example is the left turn from Commonwealth Avenue onto the Boston University Bridge in Boston, Massachusetts, where a no-left-turn sign is posted: motorists have to go around a large loop.

Ok, now let’s consider the spread from the NACTO guide, below.

NACTO pages about two-stage turn box

NACTO pages about two-stage turn queuing box

I have placed that spread online as a PDF file, zoomable to any size you might like. You may click on the link or the image above to get a larger view while reading this text. The PDF will open in a separate browser window or tab. I’ve also posted parts of the NACTO pages in connection with the text below.

Issues of organization and use of technical language

The NACTO treatment of the two-stage turn queuing box presents issues of organization and of use of technical language.

Problems start with the title of the section. A proper title is not “Design Guidance”, otherwise, every section would be named “Design Guidance”. A proper title is the name of the device, here “Two-Stage Turn Queuing Box”. [And not “Queue” but” Queuing.”]

In a proper design manual, the terms “shall”, “should”, “guidance” and “option” go from strong to weak. “Shall” is imperative: for example, a stop sign shall be octagonal. Should, guidance and option statements are increasingly weaker, leaving more room for engineering judgment.

The terms “Required Features” and “Recommended Features” correspond roughly to “shall and “should” but do not have the explicit, legally-defined meanings of “shall” and “should”.

None of the drawings on the two pages are dimensioned, and no dimensions are given in the text. That is to say, these are not engineering drawings, they are only conceptual drawings. How big are the turn boxes supposed to be? Who knows? The width of travel lanes differs from one drawing to the next, but no explanation is given for that. When politicians start beating on the door for NACTO treatments, standards-setting bodies and traffic engineers have to try to fill in the missing information. For specific projects, that task often is passed along to hired consultants who make their living by promoting and designing special bicycle facilities. Yes, there is a conflict of interest.

Specific comments

Now, either click on the image of each section of the page below to open it in a separate browser tab, or zoom the PDF to at least 50% size so you can read the text in connection with my specific comments .(You may open it now if you didn’t already.)

Comments on the left-hand page

The left-hand page includes text which may look like design specifications, and drawings which may look like design drawings — to a layperson.

Left half of left-hand page


Point 1: “An area shall be designated to hold queuing bicyclists and formalize two-stage turn maneuvers.” This is under the heading “Required Features.”  A 2STQB is only one way to turn left among others, an option, subject to engineering judgment or specific design warrants. There is neither the room nor the need for a 2STQB at most intersections. Lacking here is any statement as to where a 2STQB is appropriate, but the “shall” statement here is inappropriate: appropriate shall statements would describe what features are required if a 2STQB is installed. As of May 2014, the 2STQB is still in experimental status with the Federal Highway Administration — as are all details of its design, and so no “shall” statement at all is appropriate.

A proper design manual would include guidance about speed and volume of traffic; the additional delay usually required for a two-stage turn; whether bicyclists might take an alternate route entirely; whether use of the box is  mandatory, placing bicyclists who make other types of turns in violation of the law.

Point 4: “In cities that permit right turns on red, a no-turn-on-red sign shall be installed.”

According to the wording here, if the installation is not in a city, the sign is not required.

But also, the shall statement is overly broad, and incomplete. The sign is needed only if right-turning traffic would be in conflict with the bicyclists waiting in the 2STQB: unnecessary in the cross street if traffic turns right before reaching the box or cannot turn right, and unnecessary on the entry street if the cross street is one-way right-to-left. Does the sign belong on the entry street or the cross street, or both? That is not stated. Details, details…

Point 6: The comma makes nonsense of this sentence. Where is the box to be positioned?

The other, subsidiary “should” and “may” statements on this page also are contingent on official approval of the underlying design, and are lacking in detail.

Right half of left-hand page


Something really leaps out at me here: take a look and see whether it leaps out at you too.

OK, ready? Three of the six illustrations show a line of travel (in blue) for bicyclists straight across an intersection and then illegally and hazardously turning right, directly into the face of approaching traffic in a cross street.

In showing this bizarre routing, the NACTO Guide also fails to address issues with the actual route which bicyclists might take.

Five of the six illustrations show that bicyclists would somehow turn 180 degrees in place. That requires dismounting and is slow and awkward. How would a bicyclist turn when the traffic light is about to change? When other bicyclists are already in the box? What about tandems? Bicycles pulling trailers? Bicycles carrying heavy baggage?

The drawings show a subtly implied but selectively addressed-threat: lanes where motorists travel are shown in a threatening shade of pink — whoops: except in the cross street where bicyclists ride head-on at motorists.

Four of the six illustrations show motor vehicles in right-hook conflict with bicyclists headed for the queuing box. The motor vehicles are turning out of the threatening pink area into what is portrayed as the safe zone– the right-hook zone. In two of the pictures,  vehicles have already impinged on the blue line which represents the path of bicyclists crossing the intersection. Green paint, which has become a catch-all warning of traffic conflicts in bicycle facilities, is shown in the queuing box, it is not shown in the conflict zone. (By way of comparison, Dutch practice in such conflict situations is that the motorist must always yield, and to use “shark teeth” markings to indicate a yield line.)

Two of the drawings show bike lanes in the door zone of parked cars.

The middle left illustration shows a receiving bike lane at the top, out of line with dashed markings in the intersection, so bicyclists bear right just before they cross a crosswalk, potentially colliding with pedestrians who would expect them to continue straight.

All of the illustrations show two-stage turns across two-lane one-way streets, though the two-stage turn queuing box is most useful where a conventional left turn is illegal, unusually difficult or hazardous — for example, when turning from a major, wide arterial street with heavy traffic, or one with trolley tracks in the median.

As already indicated, none of the drawings are dimensioned and no dimensions are given in the text.

Comments on the right-hand page

The right-hand page gives annotated pictures of conceptual installations, with angled views from overhead.

Left half of right-hand page


The street going from bottom to top in the picture is one-way, as can be inferred by the direction in which vehicles are traveling. That the cross street is two-way may be inferred from the locations of traffic signals and the existence of the queuing box. A real design manual would be explicit about how a treatment would apply, depending on the directions of traffic in the streets.

The end of the traffic island next to the queuing box protrudes so far and is so sharply as to make right turns awkward. No explanation or guidance is given on this issue.

Traffic signals are shown for motor traffic on both streets, but no traffic signal is shown facing the separate bikeway in the street!

Point 3: “Shall” — mandatory — wording differs from that in the same point as made on the opposite page. A real design manual would have a single, consistent statement. “Queue box shall be placed in a protected area.” The queuing box shown here is not protected from right-turning traffic in the cross street. How would that right-turning traffic be managed, or is it permitted at all? Such issues are addressed in a real design manual.

Point 6: “Optional queue box location in line with cross traffic.” The preferred queuing box, then, is not in line with cross traffic. On getting a green light, bicyclists in the queuing box would have to merge left inside the intersection unless there is a receiving bike lane after the intersection, but none is shown. Merging inside an intersection results in hazardous conflicts and is generally illegal. What warrants the choice of one or the other option? It isn’t stated.

Point 8: The illustration shows motorists and a bicyclist inside the intersection, and so they must have a concurrent green light — or, they would if any signal were shown facing the bikeway. Markings guide bicyclists across the intersection, but also into the path of right-turning traffic. The bicyclist and the motorist in the right-hand lane at the bottom of the picture are on a collision course if the motorist turns right.

What is the meaning of the curved markings adjacent to the bicycle parking in the middle of the street? Does the lane with bicycle parking start as a lane with car parking, additionally hiding bicyclists from turning motorists? Or is this an additional lane for motor traffic, discontinued at the intersection, precisely where more lanes are needed to store waiting traffic? Not shown.

Right half of right-hand page


There is a right-hook threat at both bike lane entries to the intersection.

Bicyclists headed from bottom to top in the bike lane are riding in the door zone of parked cars, and closer to the cars after crossing the intersection.

Point 9: As in the left half of the page, placing the queuing box to the right of the travel lane when there is no receiving lane ahead assures that motorists will overtake bicyclists in the intersection and that bicyclists will have to wait for motor traffic to clear before they can proceed. Motorists waiting to turn right will be stuck behind the bicyclists. Placement out of line with motor traffic is described as the option here, rather than as the preferred treatment as on the left side of the page, and the problem is acknowledged in the caption to this drawing, though no explanation for the different choices is given.

Point 10: A jughandle may be useful if traffic is so heavy or fast that bicyclists have difficulty merging to the normal left-turn position near the center of the street, but then traffic is also so heavy and fast that a signal is usually necessary, not merely to be considered — unless there is already one upstream.

Point 11: Yes, signage may be used, but what signage? A real design manual would show the signs and where they are to be placed.

Point 12: A bicycle signal might be installed, but where? for the entry? For the exit? Its timing?

Point 13: Guide lines, pavement symbols and/or colored pavement. Which? Where? Why?

Had enough?

Bike Box at Charlesgate East

This post is about the intersection of Commonwealth Avenue eastbound and Charlesgate East in Boston, Massachusetts, an intersection with a “bike box” — a waiting area for bicyclists downstream of where motorists stop for traffic signals. More generally, this post is about the assumptions underlying the bike-box treatment, and how well actual behavior reflects those assumptions.

I have described bike boxes more generally on a Web page. There is a discussion of them also in photos assembled by Dan Gutierrez. If you are logged into facebook, you can bring up the first photo and click through the others (“Next” at upper right). Non-members of facebook, the world’s largest private club, can view the slides one by one by clicking on this link.

Dan Gutierrez has also released videos of bike box behavior here and here.

On Wednesday, September 19, 2012, I rode my bicycle to Charlesgate (see Google satellite view for location), with video cameras. I observed traffic for about an hour and shot clips of bicyclists passing through the intersection.

The bike box at this intersection is intended to enable a transition from the right side to the left side of a one-way roadway. (There is a study of a similar treatment in Eugene, Oregon, intended to enable transition from left to right. That study was released in two different versions, one from the U. S. Federal Highway Administration and another from the Transportation Research Board.)

I have now produced a video from my clips. Please view the video in connection with this article. You may view it at higher resolution on the vimeo site by clicking on the title underneath.

Bike Box at Charlesgate East from John Allen on Vimeo.

A Look at the Intersection

Let’s take a virtual tour, examining a longer stretch of Commonwealth Avenue than the video does.

West of Charlesgate West on Commonwealth Avenue, there is a bike lane in the car-door zone, tapering down to nothing before the intersection with Charlesgate West. Bicyclists can still slip by on the right side of most motor vehicles.

At some time following the initial installation, the City painted shared-lane markings near the right side of the rightmost travel lane. I have observed bicyclists riding at speed in the slot between the parked and moving vehicles,  at risk of opening car doors, walk-outs, merges from both sides and right-hook collisions. The purpose of shared-lane markings is to indicate that a lane should be shared head to tail, not side by side. These markings should be placed in the middle of a lane rather than at its edge.

Transition from bike lane to no bike lane to bike lane at right edge. Note, no shared-lane markings yet in this aerial view (Google Maps aerial view)

Transition from bike lane to no bike lane to bike lane at right edge. Note, no shared-lane markings yet in this aerial view (Google Maps aerial view)

Bike lane tapered to nothing in the door zone approaching Charlesgate West

Bike lane tapered to nothing in the door zone approaching Charlesgate West (Google Street View image)

Between Charlesgate West and Charlesgate East, parking is prohibited, and the curb line at the right edge is farther to the right. The rightmost lane used to be a wide, general purpose travel lane —  but nobody who knew the intersection drove a motor vehicle in this lane. A motorist who drove in this lane would be trapped to the right of other through traffic when it became a parking lane after Charlesgate East.

In or around 2010, bike lanes and a so-called “bike box” were installed at Charlesgate East.

The intersection with Charlesgate East as it existed before 2010 is shown in the first of the two photos below. The intersection with changes is shown in the second photo.

Intersection of Commonwealth Avenue and Charlesgate West before the additional of a bike lane (Microsoft Bing aerial view). Though there is an arrow indicating that the right lane is for through travel, it is unused, because it leads to a row of parked cars in the next block. It is a "musical chairs" lane.

Intersection of Commonwealth Avenue and Charlesgate East before the addition of a bike lane (Microsoft Bing aerial view). Though there is an arrow indicating that the right lane is for through travel, it is empty, because it leads to a row of parked cars in the next block. It is a “musical chairs” lane.

Lane reassignment at Charlesgate East: four usable travel lanes, a musical chairs bike lane, Also note left-side bike lane after the intersection.

Following the changes at Charlesgate East: four usable travel lanes, and a musical chairs bike lane. Also note left-side bike lane after the intersection, top right corner of image. (Google Maps aerial view)

A bike lane is on the left side of the roadway (upper right in the photo above) leads to an underpass. The  transition from the right side to the left side is supposed to be made by way of the “bike box”, with bicyclists swerving left across two lanes of motor traffic to wait facing the left-side bike lane as shown in the image below. Bicyclists headed for other destinations are also supposed to use the “bike box,” waiting in the appropriate lane.

Intended route for bicyclists using the "bike box".

Intended route for bicyclists using the “bike box”.

The right-side bike lane is now the “musical chairs” lane which leads into a parking lane. The City has, in a peculiar way, acknowledged this, painting what I call a “desperation arrow” just after the intersection. It is visible at the right in the photo below. It directs bicyclists to swerve  into the right-hand travel lane in the short distance before the first parked car.

Looking across Charlesgate East. The Desperation Aroow is visible at the right side of the roadway. (Google Street View)

Looking across Charlesgate East. The desperation arrow is visible at the right side of the roadway and the bike lane to the underpass is at the left side. (Google Street View)

When the closest metered parking spot to the intersection is occupied, the parked vehicle sits directly over the “desperation arrow”.

Vehicle parked legally at metered parking spot, over the desperation arrow.

Vehicle parked legally at metered parking spot, over the desperation arrow.

The designated route is not the only important one. The left-side bike lane after the intersection reduces the width of the other lanes — a particular problem for bicyclists who continue in the rightmost travel lane. Many do, in order to continue at street level rather than using the underpass.

Bicyclist Behavior

I observed that most bicyclists approached Charlesgate East in the green-painted bike lane. It is the prescribed approach to the intersection, even though it is not satisfactory for any destination.

On reaching the intersection, many bicyclists ran the red light, yielding to cross traffic. in this way, they avoided being trapped to the right of moving motor traffic. Cross traffic was easily visible and relatively light, at least in mid-afternoon when I observed it.

The bike box can serve as a waiting area only on the red light. Approaching the intersection as the light turns from red to green or on the green requires bicyclists to merge left; otherwise, they are caught short by the parked cars on the far side of the intersection.

After crossing the intersection, most bicyclists merged into the door zone of the parked vehicles in the next block. If they did this on the green, they were at the same time being overtaken by motorists. Some bicyclists looked over their left shoulder for traffic as they merged; others did not.

I saw a couple of very odd maneuvers: two bicyclists who entered on the red light and crossed from right to left in the middle of the intersection as if that were the location of the bike box — one of these bicyclists continuing in the left side bike lane, the other merging back to the right. I saw one bicyclist who made a sweeping left turn from the bike lane.

I did not see even one bicyclist swerving into the bike box as intended. This observation is consistent with Dill and Monsere’s research in Portland, Oregon. To swerve into the bike box when the traffic signal is red is to gamble on when the light will turn green, crossing close to the front of motor vehicles whose drivers are in all likelihood looking ahead at the traffic signal. A tall vehicle in the near lane can hide a bicyclist from a driver in the next lane. Often, also, motor vehicles encroach into the “bike box”, making it difficult or impossible to enter. Those bicyclists who knew about the underpass —  and chose it — merged across easily if they ran the red light, but got caught waiting at the desperation arrow, if they entered on the green light.

A few bicyclists merged out of the bike lane before reaching the intersection. Some of these, too, ran the red light, and others waited for the green. It should be noted that there are long periods in the traffic signal cycle when the block between Charlesgate East and Charlesgate West is mostly empty, making merging easy.

Improve the Situation?

So, what does this show? For me, the central lesson of all this is that the bike box is supposed to solve a problem which it cannot solve.

Also, because entering the bike box is a gamble, it is a violation of traffic law. Massachusetts General Laws, Chapter 89, section 4, states:

When any way has been divided into lanes, the driver of a vehicle shall so drive that the vehicle shall be entirely within a single lane, and he shall not move from the lane in which he is driving until he has first ascertained if such movement can be made with safety.

I’m especially concerned about bicyclists who lack basic bike handling and traffic skills being dropped into this environment which claims to remove the need for those skills but which in reality requires outsmarting the system. This leads to hazardous behavior and fear.

What could improve the situation here? I see parking as a crucial issue. Removing the 20 or so parking spaces in the block following Charlesgate East would cure the “musical chairs” situation at the intersection — well, mostly.

Vehicles would still stop to load and unload. There is no way that bicyclists can ride safely without knowing how to negotiate merges. Wherever bicyclists may travel, someone may be about to overtake. Removal of parking is a political long shot, to be sure, but on the other hand, the few parking spaces on Massachusetts Avenue can only hold a small percentage of the vehicles of people who live or work in the same block. Isn’t there a possible alternate parking location?

Improved traffic-signal timing might ease merging from the right side to the left side of the roadway in the block before Charlesgate East. Wayfinding signs and markings encouraging merging before reaching the intersection would be helpful.

In my video, I show bicyclists crossing Charlesgate East in a crosswalk. That is not to operate as a driver, but it is practical and reasonably safe because there is no right-turning traffic from Commonwealth Avenue, and traffic on Charlesgate East is not permitted to turn right on a red light. Crossing two legs of an intersection in crosswalks to get to the bike lane on the far side involves waiting through an additional signal phase. Also, a Boston ordinance prohibits riding a bicycle on a sidewalk.

One way of resolving the issue of the traffic signal’s changing as a bicyclist enters the bike box is to enable entry concurrent with a pedestrian signal interval.  Then bicyclists must wait before entering the bike box and again once having crossed it.  Considering the percentage who are unwilling to wait even through one signal interval, there would probably be even more resistance to waiting through two. Another blog post, with a video, examines travel times through two intersections in Phoenix, Arizona with this type of crossing.  The travel times are unreasonably long.

Legalizing bicyclists’ crossing Charlesgate East when motorists are held back would require a separate bicycle signal. A green signal for bicyclists after the green signal for cross traffic would not delay many motorists. There would be significant delay though, for bicyclists, tempting them to run the red light. The earlier they can cross before parallel motor traffic starts, the more time they have to merge before motor traffic behind them starts up. How soon the traffic clears is going to vary greatly with time of day.

I’d like to make a case for a “bicycle boulevard”– a street which bicyclists can use for through travel, but where barriers and diverters require motorists to turn at the end of the block, on Marlborough Street, to the north of Commonwealth Avenue; and/or Newbury Street, to the south. There would have to be a new bridge across the Muddy River at Charlesgate; for Newbury Street, also a tunnel under a ramp to the overpass; or Marlborough Street, a connection under the Bowker Overpass to Beacon Street and Bay State Road. I have suggested elsewhere that Bay State Road be reconfigured as a two-way bicycle boulevard.

Such a bridge might be an element of a redesign of Charlesgate Park — originally an attractive link between Olmsted’s Emerald Necklace park system and the Charles River Esplanade, now blighted by the Bowker Overpass which looms over it. However, the Bowker overpass crosses the Massachusetts Turnpike Extension, a limited-access highway.  Restoring ground-level access maintaining access across the Turnpike would require major reconstruction.



Danish story, video and comments on the Albertslund-Copenhagen “bicycle superhighway”

A reader pointed me to a news story on the politiken.dk blog about the Copenhagen/Albertslund “bicycle superhighway” which is getting attention and publicity. The reader’s comments on my previous post read:

Yeah, its kind of joke, but to be fair they are not called superhighways in Danish but Super bicycle tracks, and even then most agree that they are not really that super. There is a video of the entire route here if you scroll down a bit:


The two next ones which will open are another story though, as they mostly have their own right of way, and use viaducts or bridges to cross streets.

So, better things may be on their way, but…I ran the article through the Google translator, and it appears in the link below in (sort of) English. The page includes the sped-up video of the entire route.


Here’s the video — warning, Shell diesel fuel ad at start, and you can only stop the video when you click on it, see the ad again and click on it to open a bigger ad! This workaround was needed to make the video visible on this page.

The one unifying factor of this route is an orange line painted lengthwise to identify it. The first part of the route is relatively tame. Barriers, unprotected intersections and other hazards pile up near the end.

Some representative quotes (I’ve translated from Googlish to English, thanks to an online dictionary and my knowledge of the neighbor language, German.):

From the article:

“I did not expect that I just had to detour on ordinary roads in residential neighborhoods. I did not see much of the green wave that is supposed to be in town. I do not think you can call it a super bike path,” the [politiken dk test rider] concluded.

From comments on the article:

– The section of tunnel under Motorring 3 is dark and miserably lighted. There are many riding schools (which, incidentally, should be forced to close and move out into a rural area!). The tunnel is usually filled with horse s***, and because you can not see in these tunnels due to poor lighting, you can only hope that you do not ride through any of it.


– In the westbound direction, at the pitch-dark tunnels, you have to negotiate two sets of barriers. The point of these, other than to impede traffic, I do not know. But when you have to use all your mental energy to get through these, they constitute more of a hazard than a safety precaution.


I have commuted between Roskilde and the northwest part of Copenhagen 2-3 times a week on a recumbent trike with an electric assist motor for 6 months (http://ing.dk/blogs/pedalbilen). When I used the “super path” the trip was about 3 km and 15 minutes longer. Especially the part of the route in Albertslund is very indirect and inconvenient. There are detours, barriers and ramps in most places, and it will for example not be possible to ride in a velomobile, as far as I can judge. The new route is comfortable and free of exhaust, but as commuter route it gets a failing grade compared with Roskildevej [a parallel, 4-lane divided but not limited-access highway with one-way sidepaths].


– I didn’t see anything which shows that cyclists have priority over the other traffic. Unfortunately, the only thing new that I see is approximately 100 meters of new asphalt in two places near Rødovre, so that it is easy going. There are simply no real improvements for cyclists in relation to other road users! You can still find barriers, sharp turns, bumps and traffic lights. Why is there no new cycle path, e.g. along the western forest road, so you do not have to drive through neighborhoods with pedestrians and children playing? Why are barriers not turned 90 degrees, so users of the route have right of way?

Even if there were brand new asphalt on the entire route it would never merit the title “super”. Only when a route enables more or less continuous travel at high average speed (which motorists know from motorways) does it, in my opinion, deserve the massive marketing it is currently getting.


…Bus passengers cross the bikeway. It seems quite unreasonable that there are no islands at bus stops where passengers have to wait when they get on and off. Thus cyclists must stop, and so, so much for the “super bike path”.

A ride on Comm Ave., Boston, Massachusetts, USA

Comm Ave. Boston: Kenmore Square, Mass Ave. underpass from John Allen on Vimeo.

This is a 4-minute continuous video of a bicycle ride in Boston, eastbound on Commonwealth Avenue through Kenmore Square, to and through the underpass at Massachusetts Avenue. I recommend that you view it on Vimeo site, in full-screen high definition.

Gordon Renkes and I each had a camera, so you can see both a forward and rearward view. We rode safely, and mostly by not using the special bicycle facilities.

Some highlights:

  • The block pavers, bricks and the granite curbstones used as borders for crosswalks made for a very bumpy ride across Kenmore Square and the next intersection.
  • The bike lane for the first block after Kenmore Square was unusable, due to double-parked vehicles. In the next block, it was unsafe, due to the risk of opening car doors and walkouts. One trucker was accomodating enough to park entirely outside the bike lane, inviting bicyclists to run the gauntlet between the truck and parked cars Gridlock Sam-style. We didn’t take the invitation.
  • As we waited for a traffic light, a cyclist raced past us on the right, entering the narrow channel between a row of stopped motor vehicles and one of parked cars. If anyone had walked out, or a car door had opened, the cyclist would likely have had too little time to react, and he would have had no escape route. At least he (and the pedestrian he could have struck) would have been fortunate in that one of the waiting vehicles was an ambulance.
  • There is a bike box along the route, and revealed an issue that I hadn’t noticed before. If the traffic light is red, you’re supposed to filter forward in the bike lane on the right, then swerve across two lanes of traffic to the middle of the 4-lane wide bike box, to be in line with the bike lane which is to the left of 2 lanes — see Google satellite view — note that this is an angle shot from the west. If the light is green, you could merge either before or after the intersection, but there is an advantage in merging before the intersection, as the counterexample of the video shows. You also don’t know when the light is going to change — so in either case, you make a widely divergent choice — merge left, or head for the bike lane at the right — based on insufficient information, and if the light is red, you also could be swerving abruptly across two lanes of traffic just as the light turns green.
  • The buffered bike lane in the underpass makes for an easier ride through the underpass, but where it connects to a narrow left-side bike lane outside the underpass, there is little clearance for motor traffic in the next lane, which is the faster of two travel lanes. There also is a risk of left-hook collisions. I used to ride in the right lane, claiming the lane, and that was simpler and less stressful.

More general comments:

  • The block pavers, bricks and curbstones buried in the street are not bicycle-specific, but certainly not bicycle-friendly. I predict that they will be paved over within a few years as they deteriorate.
  • The attempt to engineer a “bicycle friendly” or “low-stress” solution on busy, crowded Commonwealth Avenue is like ornamenting a pig with lipstick, costume jewelry and a party dress. The bicycle-specific measures, except the bike lane in the underpass, fly in the face of the way traffic works, and the way it uses this street. Experienced, competent cyclists like Gordon and me know how to avoid the hazards, but they worsen our experience anyway — it is in Kenmore Square (during another ride) that I first heard the call “get in the bike lane” in Boston. Less knowledgeable bicyclists garner a false sense of security, following the painted lines, and expose themselves unnecessarily to risk.
  • Meanwhile, other, better solutions beckon. I have long advocated that Boston designate and improve alternative routes on lightly-traveled streets for through bicycle travel. That would be especially easy in Back Bay, with its grid layout. My candidate for an alternative to Commonwealth Avenue would be Newbury Street, the next one to the south, a shopping street which could make a very nice bicycle boulevard, and which, with a little bridge across the Muddy River, would also connect under the Bowker Overpass into the Fenway area. A worse solution also has been proposed: the City is considering a so-called “cycle track” — a bikeway behind a row of parked cars — on the next Street after Newbury Street, Boylston Street. More about these topics later…

Bikes, Cars, Light Rail, E. Jefferson St., Phoenix, Arizona

Build it and they will…wait. Well, at least they’re supposed to wait.

If you click on the title in the image or caption, you can view this at a higher resolution.

Bikes, Cars, Light Rail, E. Jefferson St., Phoenix, Arizona from John Allen on Vimeo.

An intersection with light rail, motor vehicles and bike lanes requires bicyclists to cross from one side to the other of a multi-lane street, resulting in delays of 2 to 3 minutes. Alternative solutions are described.

The Six-Way in Rush Hour

Here’s another video showing conditions at the six-way intersection of 16th Street, U Street and New Hampshire Avenue NW in Washington, DC, where special bicycle facilities have been installed.

Also please see my earlier post about this intersection, with another embedded video.