Cambridge Civic Journal Forum

October 6, 2013

Cambridge at cross purposes about traffic

Readers of the newsletter of the Belmont Citizens Forum will find much news there about neighboring North Cambridge. Editor Meg Muckenhoupt’s lead story in the September-October 2013 issue is about major, new housing developments planned for the part of Cambridge west of Alewife Brook Parkway and north of Fresh Pond Park. The article expresses concerns with traffic which is already approaching gridlock and affecting access to the Alewife T station.

Quoting from the story:

The decision document issued by Cambridge’s Planning Board for the 398-unit 160 Cambridgepark Drive, which is predicted to cause 1,324 new trips, states, “The project is expected to have minimal impact on traffic and will not cause congestion, hazard, or substantial change to the established neighborhood character.” Ominously, the decision continues: “It is also noted that the traffic generated by the project is anticipated to be less than that associated with the office/research and development project on 150, 180 and 180R Cambridgepark Drive for which entitlements currently exist under a previously granted special permit.” In short, if the city of Cambridge accepted a potential increase in traffic for a special permit in the past, the city should accept that increase in traffic for all future permits—no matter how much the population has increased in the meantime.

[…]

Concord Avenue and the Alewife Brook Parkway rotary won’t escape traffic woes. Cambridge’s 2005 Concord Alewife Plan included a “critical movement analysis” of the area. Critical movements are conflicting traffic movements. They are the times when vehicles block each other from moving, such as when a car turns left and crosses a lane of oncoming traffic. The Concord Alewife Plan reports that for the area roughly bounded by the Route 2/Route 16 intersection, the Alewife Brook Parkway, and Concord Avenue, service starts to deteriorate when a roadway reaches the “critical sum” of 1,500 vehicles per hour, or 1,800 vehicles per hour for rotaries. Below those numbers, and most motorists can get through an intersection in two or fewer light cycles. Above those thresholds, you’ll wait at that light a long time. As of 2005, the Concord/Route 2 rotary was already operating at 1,880 critical interactions—80 above the threshold—with a total traffic volume of 4,300 trips per day, while Concord Avenue at Blanchard Road had already reached 1,400 “critical sums” per hour, with 2,460 trips per day.

The report also predicted vehicle trips per day for 2024 for the area after Cambridge’s rezoning (which Cambridge enacted in June 2006.) The permitted 70 Fawcett Street development, which will be located between these two intersections, by itself promises to add enough vehicle trips to reach the predicted 2024 buildout trip level by 2014—and there’s plenty more space for apartments and garages alongside between the Concord Avenue rotary and Blanchard Road.

Also:

Of course, some of these buildings’ residents will take the T to work—if they can fit on the T…The Red Line is already “congested” and running at capacity, according to a June 2012 study by the Urban Land Institute titled Hub and Spoke: Core Transit Congestion and the Future of Transit and Development in Greater Boston.

So, Cambridge publishes a plan for the Alewife area which reports that traffic congestion is already a problem, but then it permits several large housing developments which will worsen it. The Belmont Citizens Forum article does report that design study has been funded for a new bridge over the commuter rail tracks west of Alewife Station, connecting it with Concord Avenue. That will relieve some congestion near the Alewife Brook Parkway/Concord Avenue rotary but will have little effect elsewhere. And this is still only a design study.

As a bicycling advocate and repeated critic of Cambridge’s treatment on Concord Avenue — see summary of my comments here — I have found another major inconsistency with the 2005 Concord-Alewife Plan: the recent reconstruction of Concord Avenue so as to maximize the number of conflicts between bicyclists and motorists. The new traffic signal just west of the Concord Avenue/Alewife Brook Parkway rotary backs up traffic into the rotary whenever a bicyclist or pedestrian actuates the signal to cross. The westbound sidewalk bikeway installed on the north side of Concord Avenue crosses a driveway or street on average once every 100 feet, requiring motorists to stop in the only westbound travel lane, blocking traffic, to yield to bicyclists overtaking on their right. Buses traveling both ways on Concord Avenue must stop in the travel lane, where their doors open directly into the bikeway. The conflicting turn movements between motorists and bicyclists, and bus passengers discharged onto the the bikeway, pose serious safety concerns too.

In previous posts on this blog and elsewhere, I recommended a two-way bikeway on the south side of Concord Avenue next to Fresh Pond Park, where there is only one signalized intersection, and maintenance of the previous roadway width and bike lanes.

The 2005 Concord-Alewife Plan contains no mention of the Concord Avenue bikeway — see recommendations for Concord Avenue on page 80 of the report. The plan therefore does not account for the congestion caused by the bikeway, on which construction began only 4 years later.

The overall impression I get is that Cambridge’s planning is disorganized, but also, Cambridge’s bicycle planning occurs in a fantasyland where the well-known conflict situations which cause crashes are greeted with a claim that the goal is to make bicycling more attractive, then, poof, when there are more bicyclists, by magic, bicycling will become safer. I call this the “Pied Piper” approach to bicycle planning. Well, actually, Cambridge is reporting a steady level of bicycle crashes in spite of an increasing volume of bicycle traffic. Some decrease in risk with increasing volume occurs with any mode of transportation as its users gain longer experience. The issue I have is with using this as an excuse for wishful thinking and crap design, and writing off the victims of preventable crashes as expendable. Cambridge has had some gruesome preventable crashes, and has intersections with the highest volumes of bicycle crashes anywhere in Massachusetts.

Another overall impression which I can’t shake is that Cambridge is very selective about reducing traffic congestion. The Concord Avenue project; the residential developments planned for the Alewife area; the Western Avenue roadway narrowing and sidewalk bikeway; and the proposed bikeways along Binney Street increase congestion at the portals to the city. It all strikes me as rather desperate and underhanded way to decrease congestion in the core of the city, but there you have it, as it appears to me.

[Added paragraphs, October 7, 7:40 AM] Residential development close to the urban core is certainly preferable to sprawling suburbs to minimize environmental impacts and traffic congestion, but resolving the traffic problems in the Alewife area would require major investments to increase Red Line and bus service, and disincentives (read: high cost) for single-occupant motor vehicle travel. The public resists all of these. If there is a logic to the City’s approach to these challenges, it is to break down resistance by making the problems so pressing that the pain becomes intolerable.

Bicycling and walking can make some contribution, but the plans for the new housing developments describe it as small. Quoting again:

To be fair, the developers of these various projects are attempting to make car-free commuting more attractive to their residents. Several of these buildings have extensive bicycle-parking facilities, including the Faces site and 160 Cambridgepark Drive. But the city of Cambridge doesn’t anticipate that those bicycles will get much use. For 398-unit 160 Cambridgepark Drive, for example, the city estimates the residents will make 1,324 daily car trips, and 202 pedestrian trips, but just 98 journeys by bike.

Most of the traffic in the area in any case is to or from more distant locations, or is passing through. Bicycling and walking may serve as feeder modes for these longer trips but don’t compete well with motorized modes to cover the distance.

August 7, 2013

Longfellow Bridge Rehabilitation Project -MBTA Red Line Weekend Diversion – August 10 and 11

Filed under: Cambridge,transportation — Tags: , — Robert Winters @ 6:14 pm

Longfellow Bridge Rehabilitation

On Saturday, August 10 and Sunday, August 11, the Massachusetts Department of Transportation (MassDOT) will close the Longfellow Bridge to all motor vehicle travel, except MBTA buses. The closure is to implement an MBTA Red Line diversion related to bridge construction. Buses will replace Red Line trains for service between Kendall/MIT Station and Park Street Station, with a stop at Charles/MGH Station. [Map of bus route and stops]

Bus service will be in place for Boston and Cambridge-bound Red Line customers from the start of service on Saturday, August 10 to the end of service on Sunday, August 11. Red Line trains will resume service on Monday morning. The diversion is necessary for MassDOT’s design/build contractor, White-Skanska-Consigli JV, to perform work in close proximity to the Red Line tracks that is not allowed during MBTA service hours. Please visit the MBTA’s service updates webpage for additional information.

MBTA buses will be the only motor vehicles permitted on the bridge. All other motor vehicles including passenger vehicles, trucks and all other buses will need to use one of two routes shown on the attached detour map to reach Boston. One route uses Memorial Drive westbound to make a U-turn at Ames Street for access to Memorial Drive eastbound to Land Boulevard and Charles River Dam Road (Monsignor O’Brien Highway/Route 28) to reach Leverett Circle. A second route uses 3rd Street and Binney Street to reach Land Boulevard. Truck restrictions are in place for Memorial Drive. [Map]

Emergency response, bicycle and pedestrian access will be maintained across the bridge during this weekend diversion. Please note: Bicyclists will be asked to walk their bikes on the sidewalk across the Longfellow Bridge to ensure the safety of all bridge users.

The Cambridge-bound detour remains in place using a signed route from Charles Circle following Charles Street to Leverett Circle, Monsignor O’Brien Highway/Charles River Dam Road and Edwin H. Land Boulevard. [Map]

For more information on the project and traffic management plans, visit the website at www.mass.gov/massdot/longfellowbridge. For questions, to report issues and concerns related to construction or to be added to the project email distribution list, please call the project hotline at 617-519-9892 or email longfellowbridge@state.ma.us.

December 3, 2012

Enjoying? the Concord Avenue “raised bike lanes”

The Cambridge City Council meeting on December 3, 2012 is to address issues of debris on the Concord Avenue “raised bike lanes”. These replaced conventional bike lanes at street level. I put the term “raised bike lanes” in quotes because a bikeway behind a curb is not a bike lane. By definition, a lane is at street level, so it is possible to merge to and from other lanes. Rather, this is a nonstandard bicycle path.

This post supplements comments which I posted on my own blog before Concord Avenue was reconstructed. The photos here are stills from video shot during a ride westbound at mid-day on November 20, 2012, with moderate motor traffic and very light bicycle traffic.

First photo: Crosswalk just west of the Alewife Brook Parkway rotary is backing up motor traffic. This already generates traffic jams with light bicycle traffic. The City expects the bikeways to attract more cyclists and to lead to a major increase in bicycle traffic.

Crosswalk backs up traffic on Concord Avenue

Crosswalk backs up traffic on Concord Avenue

Next photo: The westbound bikeway crosses 8 streets and 24 driveways in 3000 feet. The most persistent hazard on the westbound bikeway is of “right hook” and “left cross” collisions. The van in the photo not only is turning across the bikeway; it also might be hiding another vehicle preparing a left turn from ahead. The bikeway places bicyclists where they are defenseless against these threats. I say more about them, and how to avoid them, in my earlier blog post.

Right hook and left cross threat on Concord Avenue bikeway

Right hook and left cross threat on Concord Avenue bikeway

Next — bus stop. When the bike lanes were at street level, bicyclists could pass a stopped bus on the left, or wait behind it. Motorists also usually could pass a stopped bus. Passing would have been even easier with bus turnouts on the westbound side, where there is only one travel lane. Now that the roadway has instead been narrowed, converting the conventional bike lanes into “raised bike lanes”, buses must completely block the travel lane, and passengers getting off a bus step down directly into the path of bicyclists. A 2007 research study in Copenhagen showed an increase in bicyclist-pedestrian collisions of 17 times, and of injuries of 19 times, when bus stops were placed outside bikeways like this. More about that study.

Bus stop on Concord Avenue, with green paint

Bus stop on Concord Avenue, with green paint

That study was published well before construction on the Concord Avenue bikeway began. Not only that, the City’s bicycle coordinator repeatedly points to Copenhagen as a model of what Cambridge should do.

To resolve conflicts between bicyclists and passengers descending from buses, the City first painted bicycle markings. Those markings, however, suggest that bicyclists have priority, and these markings also may not be directly in front of a bus’s door when it opens, to warn the passengers. At some later time, green carpet painting was added. This is normally used to indicate where motorists yield to bicyclists (see Federal Highway Administration interim approval), but here it is intended to indicate where bicyclists must yield to pedestrians, a confused and contradictory message. This bus stop is at a driveway. Traffic has worn away some of the green paint and you can see the bicycle marking which was painted over.

Bicycle marking under green paint at bus stop on Concord Avenue

Bicycle marking under green paint at bus stop on Concord Avenue

One problem to be discussed at the City Council meeting is that snow clearance is not practical on the westbound bikeway, because of its repeated ups and downs. Ice also puddles there. Here’s a photo from another blogger, dr2chase, showing winter conditions on the westbound bikeway. dr2chase’s blog has many more photos.

dr2chase's photo of winter conditions on the Concord Avenue bikeway westbound

dr2chase’s photo of winter conditions on the Concord Avenue bikeway westbound

dr2chase also has made the point that snow clearance is much more practical on the eastbound bikeway, which has only one driveway entrance in its entire length. Here is his photo illustrating that:

drchase's photo of the eastbound bikeway in winter

drchase’s photo of the eastbound bikeway in winter

The bikeway on each side is designated as one-way. People are likely to use both of them for two-way travel, and not only in snow season, because a cyclist must stand in the street to lift the bicycle over the curb of the eastbound bikeway at most locations. Also note the seam between asphalt and concrete running down the middle of the photo above. It is intended to separate bicyclists from pedestrians. It won’t, especially with two-way bicycling, and over the years, it will deteriorate so it traps bicycle wheels. dr2chase and I have both made the point that a properly-designed, designated two-way bikeway on the south side of Concord Avenue, adjacent to Fresh Pond Park, would have made good sense, connecting with the existing bikeways in the park and crossing only one driveway in its entire length — at a signalized intersection. I also would have liked to keep the street at its previous width, with street-level bike lanes, to allow efficient through travel and make it possible to reach the eastbound bikeway without lifting a bicycle over a curb.

The next photo illustrates the crossing-the-street issue. Note the driveway at the right rear, and that there is no break in the curb on the far side of Concord Avenue. To cross without stopping in the street, and to avoid having to double back, cyclists will most likely ride eastbound in the westbound bikeway. That is illegal and hazardous: motorists pulling out of side streets and driveways look in the opposite direction for traffic.

The mailbox adjacent to the 5-foot-wide bikeway adds a nice touch as well. Nick it with your handlebar, and you go down hard. Even without such obstructions, 5 feet is minimal for one-way travel. This mailbox is one of a large number of fixed-object hazards adjacent to the bikeway.

Mailbox, and curb on far side of Concord Avenue

Mailbox, and curb on far side of Concord Avenue

Not all hazards are fixed-object hazards. There are these trash barrels.

Trash barrels on westbound bikeway on Concord Avenue

Trash barrels on westbound bikeway on Concord Avenue

Behind the trash barrels, you may have noticed a car discharging passengers. A cyclist who regularly rides Concord Avenue reports that delivery vehicles also now stop in the bikeway.

Car stops in bikeway to discharge passengers, on Concord Avenue

Car stops in bikeway to discharge passengers, on Concord Avenue

My next photos show what I call the X-merge, or double-cross merge.

Normal traffic law requires a driver to maintain a constant lane position when another driver is overtaking. Here’s an excerpt from the Massachusetts law:

Except as herein otherwise provided, the driver of a vehicle passing another vehicle traveling in the same direction shall drive a safe distance to the left of such other vehicle and shall not return to the right until safely clear of the overtaken vehicle; and, if the way is of sufficient width for the two vehicles to pass, the driver of the leading one shall not unnecessarily obstruct the other.

Bicyclists may overtake on the right, according to another section of the law:

…the bicycle operator may keep to the right when passing a motor vehicle which is moving in the travel lane of the way…

When a bicyclist is directed to merge from right to left at an arbitrary location, and a motorist to merge from left to right at the same location, they are both violating the law. Green paint here is used to direct cyclists and motorists to operate illegally.

X-merge on Concord Avenue

X-merge on Concord Avenue

I avoided right-hook threats by merging in behind the stopped car so the next vehicle turning right could safely pass me on the right.

Avoiding the X-merge on Concord Avenue

Avoiding the X-merge on Concord Avenue

Before Blanchard Road, a traffic island narrows the roadway. The bike lane, between the through travel lane and right turn lane, is too narrow to allow safe clearance on both sides. Note in the photo below that the narrow median on the far side of Blanchard Road allows much more room to the left of the bike lane. The traffic island predates the reconstruction: the bike lane has been shoehorned in by narrowing the other lanes. Concord Avenue is wide enough to accommodate turning traffic without the island’s being so wide.

Wide traffic island at Blanchard Road narrows bike lane on Concord Avenue

Wide traffic island at Blanchard Road narrows bike lane on Concord Avenue

Well, enough. You get the idea. I’ll finish with a couple of quotes. Here’s one from MarkS, commenting on dr2chase’s blog post:

I don’t know why they wasted the time and money to put these tracks in in the first place. I find a bike lane much more convenient, and in some ways safer — clearly safer than that abomination on the north side of Concord Ave — the “outgoing” side. And, if ever we decide to re-design the situation, the expense of doing so will be significantly — and that’s an understatement — more than it would be to just re-paint the lines where the bike lane would have been.

Here’s another quote, from dr2chase:

…the west-bound side is about the most ineffective botch I have ever seen. But the eastbound side is quite nice (with the exception of the scary-high curbs). One extremely-low-traffic intersection, no driveways, hence none of those risks, and so wide that (with current bike/ped traffic levels) there is little harm in riding the wrong way on the good side. Technically illegal, but vastly safer, and I cannot fault someone for making the safer choice.

I agree! And have a look at the video online!

Save

Save

Save

November 14, 2012

Cycle track disease is contagious!

It crosses over from Cambridge to hit the slippery slope (literally) in Somerville.

Please see my extended comments here: http://john-s-allen.com/blog/?p=4862

July 27, 2012

City Council to discuss last December’s fatal bicycle crash

On Monday, July 30, 2012, the Cambridge City Council is to discuss a City Manager’s report on the December, 2011 fatal truck/bicycle crash at Vassar Street and Massachusetts Avenue. (I commented on that crash in an earlier post in this Forum).

The city has posted the agenda of the meeting. The City Manager’s report on the crash is on that agenda.

I’ve posted that report here — indented, with my comments unindented:

July 30, 2012

To the [City Council]:

In response to Awaiting Report Item Number 12-63 relative to a report on safety issues at the intersection of Massachusetts Avenue and Vasser [sic] Street, Director of Traffic, Parking and Transportation Susan E. Clippinger reports the following:

In response to the fatal bicycle crash on December 27, 2011, the Traffic, Parking + Transportation Department conducted a review of the intersection that included the operation of the traffic signal, signs and pavement markings of the intersection, and a review of the crash history of the location.

Using both the Massachusetts Department of Transportation and Cambridge Police Department crash information, TP+T reviewed 19 incidents involving bicycles which occurred in the 5 years between 2007 and 2011 (excluding the fatality which was under investigation). The purpose of the review was to determine if a common type of crash was frequently occurring and if engineering measures could be implemented to prevent future crashes.

A Policy Order Resolution from the May 14 City Council meeting (third page here) describes Vassar Street and Massachusetts Avenue as the second-worst intersection for crashes in the city, and reports 55 crashes, with 24 involving “cars” (which I take to mean all motor vehicles). Clippinger reported on 19 bicycle-motor vehicle crashes over a 5-year period — however, single-bicycle, bicycle-bicycle and bicycle-pedestrian crashes are just as real. Perhaps Clippinger did not report on 5 of the bicycle-motor vehicle crashes because evidence was too sparse, but on the other hand, what about the remaining 31? All 55 crashes were serious enough that police reports were filed. Also, bicycle crashes of all kinds, especially those not involving motor vehicles, are greatly under-reported to police.

A couple years ago in a national Webinar, the City’s bicycle coordinator, Cara Seiderman, said that there had been no crashes on the Vassar Street sidepaths. Evidently, she excluded intersections, and even so, her statement was incorrect. There had been at least two bicycle-pedestrian crashes on the sidepaths in which someone was taken away in an ambulance. Following each of these crashes, one of the parties e-mailed me, having read my online comments about the sidepaths. There have almost certainly been additional crashes.

Clippinger’s report continues:

We found that in 17 of the 19 crashes, the bicycle was proceeding through the intersection and was not turning left or right. In eight of the 19 crashes, the vehicle was turning right. A common cause of this type of crash is that either the driver fails to yield upon turning or the bicycle is traveling too fast to stop in time for a vehicle that is in the process of turning.

Clippinger places the responsibility on the motorist to look to the right rear to yield to bicyclists who are foolishly overtaking on the right. Bike lanes to the right of right-turning traffic at intersections, as here, encourage bicyclists to make this mistake.

It also appears that most of these crashes were minor; only two crashes resulted in the cyclist’s being transported to the hospital.

17 of the 19 cyclists described in the report evidently were lucky. Such “coffin corner” crashes are often fatal when the right-turning vehicle is a large truck or bus. However, Clippinger doesn’t report how serious any of the injuries were, whether or not the cyclists were transported to the hospital. To be fair, she may not have had access to this information. It’s hard to get.

Based on the limited information we have on the location and direction of the cyclist involved in the December 27 crash, TP+T determined that this crash is not consistent with the crashes experienced previously at this location. Further, we determined that the traffic signal operation, signs, pavement markings, and layout of the intersection did not contribute to this crash.

I agree that this was a different type of crash. However, features of the intersection almost certainly contributed to the crash. As I noted in my review of the Tech article — and as reported by eyewitnesses — the right turn was difficult for the trucker because of a bulbout and street furniture on the corner. It is likely that the driver was looking into his right side-view mirror to make sure that the truck cleared the street furniture, and so failed to see the bcyclist. To clear the street furniture, the truck crossed the centerline on Vassar Street, placing it in head-on conflict with traffic in the oncoming left-turn lane, one of the possible locations of the cyclist. The layout of the intersection had nothing to do with this?

However, I think that the cyclist most likely was crossing in front of the truck from right to left. In that case, he had been riding wrong-way on the Vassar Street sidepath, and then turned to his right across the street. The sidepath and connecting bike lane enable this conduct. He could have been looking to the right for traffic, and failed to notice the truck on his left. Also, his brakes may have functioned poorly in the wet.

Clippinger concludes:

TP+T remains fully committed to improving the safety of our roads for all users, particularly for pedestrians and bicycles. We continue to research causes of crashes citywide, and each year we use that information to make engineering improvements we feel will reduce the number and severity of crashes.

“We feel”. I’d prefer a stronger report, examining all types of crashes, and a bicycle program guided by careful research rather than feelings.

May 18, 2012

Reports on December, 2011 fatal truck/bicycle collision

(Note: this post has been updated since first placed online, because readers have asked for images to clarify the location and details of the incident. Also see comments following this post. Review of the reports, images and comments has led to some changes in the post, as well.)


The MIT student newspaper, The Tech, has obtained and posted copies of some of the police reports on the truck-bicycle crash on Dec. 27, 2011 which resulted in the death of an MIT graduate, Phyo Kyaw, ’10. I comment here on the Tech story about the crash, and the police reports it links to.

I study bicycle crashes — it’s part of what I do in my profession, but I offer the following comments for free as, I hope, some small service to the MIT community and to the public at large. [Disclaimer, if needed: I am an MIT alumnus. That is, to some extent, why I take the trouble to write this.]

To sum up what I’m about to say, there’s enough blame to go around. Also, the crash investigation failed to look into a number of significant issues or to frame the legal issues accurately. It shows considerable bias toward the truck driver. The Tech‘s reporting missed on a few points. Specifics follow.

The Google satellite view below shows the intersection. The truck was turning the same corner as the tourist “trolley” bus with the green roof shown in the satellite view. This view is from the west, and so north is at the left in the image.

Massachusetts Avenue and Vassar Street, Cambridge, Massachusetts, USA

Massachusetts Avenue and Vassar Street, Cambridge, Massachusetts, USA. Note that north is to the left in this image.

(Cambridge Civic Forum’s blog software won’t let me embed the actual Google view, in which you could scroll around, look from other angles, zoom in and out etc. but you can link to the Google view here.

Now we add Kyaw on his bicycle. He may have been traveling toward Massachusetts Avenue on Vassar Street and stuck the truck head-on, as shown by the arrow coming down diagonally from the upper left in the image below — or traveling toward MIT on the sidewalk of Massachusetts Avenue, as indicated by the arrow at the lower left — or crossing the street from MIT, but not in the crosswalk, as indicated by the arrow pointing straight down from the top. The semitrailer truck crossed the centerline of Vassar Street as it turned. The crash occurred at night, in the rain.

Update: surveillance video excludes Kyaw’s approaching on the sidewalk of Massachusetts Avenue. Damage to the bicycle confirms that it was struck on its left side. Kyaw most probably then was traveling westbound in the eastbound bike lane on Vassar Street and cut across the street in front of the truck.

Massachusetts Avenue and Vassar Street, indicating possible direction of travel of bicycle

Massachusetts Avenue and Vassar Street, indicating possible direction of travel of bicycle

Here is the intersection seen in a Google Street View from the direction of the approaching truck. The three arrows, again, show directions from which Kyaw on his bicycle may have been approaching the intersection. (Update: but not the leftmost arrow in the photo.)

Intersection seen from direction of truck, with arrows indicaing possible approaches of Kyaw on bicycle.

Intersection seen from direction of truck, with arrows indicaing possible approaches of Kyaw on bicycle.

You may also view this Street View in Google Maps.

Here is the Massachusetts State Police diagram showing the final location of the truck, and of Kyaw (to the left of the trailer, on Vassar Street).

Massachusetts State Police diagram

Massachusetts State Police diagram

As also described in the Massachusetts State Police accident reconstruction report, the bicycle contacted the truck’s front bumper and came to rest under the dual tandem left rear wheels of the cab. It evidently was dragged quite a distance farther than Kyaw. The report indicates that Kyaw was not riding in the bicycle lane on Vassar Street (also assuming that he was traveling head-on toward the truck) — but does not indicate that the truck had crossed the centerline of that street. There is similar bias later in the report. As described in The Tech:

“The possible cause of this collision was the encroachment of the bicycle into the path of the turning tractor trailer unit,” the [Massachusetts State Police vehicle accident examination] report [page 6] said.

Encroachment of the bicyclist into the path of the truck when the bicyclist was described as on the right side of the street and the truck partially on the left side? Encroachment means that a vehicle is where it isn’t supposed to be. The bicyclist was encroaching, then?

Different considerations apply if Kyaw was not approaching the truck head-on; I’ll discuss them later.

The reconstruction report goes on to say that

…roadway design and engineering did not precipitate or contribute to this collision.

Nonsense. Though they are not mentioned in any of the reports, a bulbout and street furniture on the corner made the turn difficult for the truck, forcing it across the centerline of Vassar street. The truck driver may have been looking in his right rear side-view mirror to make sure that the rear of the trailer cleared the obstacles.

The Tech goes on to say:

Kyaw’s bicycle’s final position was not in a bicycle lane, the report said. Local laws do not require bicycles to travel in the bicycle lane, and it is common for left-turning bicycles to travel in Vassar’s left lane.

The observation about the law is correct other than that it’s state law, but the last part of the quote is incorrect and misleading. Assuming that Kyaw was traveling along Vassar Street toward the truck, he was in the left-turn lane. Bicyclists must merge out of the bike lane to go straight or turn left without conflict with through and right-turning traffic, or with traffic stopped at the curb. I happen to have a Web page with photos of this very intersection illustrating that point.

Again, however, Kyaw may not have been traveling head-on toward the truck. Then the bike lane is irrelevant, because he then would have been crossing the street, and it is impossible to cross the street while remaining in a bike lane.

The Tech also stated that

The reconstruction report cited contributing factors of “moderate to heavy rainfall,” Kyaw’s nonreflective clothing, Kyaw’s presumed high speed, and the lack of a front light on the bicycle.

A headlight is required by law. The lack of a headlight makes sense as a contributing factor, assuming that the truck driver was looking in Kyaw’s direction, placing some of the responsibility for the crash on Kyaw. Reflective clothing is not required by law. A reflector or reflective material only works if headlights are aimed at it. Rain also may have affected Kyaw’s ability to see. Eyeglasses were found at the scene, and when beaded with rain, they spread glare. Kyaw, like the truck driver, may not have been looking ahead. To merge toward the center of the street, Kyaw should have looked back over his shoulder for overtaking traffic.

The Tech continues:

Kyaw was wearing a helmet at the time of the accident, Cambridge Police report #5 said. The bicycle was “not equipped with a front-facing light,” and its front white reflector was partially obstructed by brake and shifter cables, the report said. Massachusetts law requires bicycles to have a front light at night.

Cables obstructing a reflector don’t seem a likely explanation. They’re too narrow unless the reflector is very small. How the position of the cables could be determined from a bicycle that had gone under a truck also isn’t at all clear. The reflector may, however, have been obstructed by Kyaw’s hand, or its reflective properties compromised by dirt or beads of rainwater. The truck’s headlights were in any case not aimed at Kyaw to light up the reflector as the truck rounded the corner. A large truck’s cab is so high above the headlights that a bicycle’s reflectors barely work if the bicycle is close, see explanation here. A vehicle ahead of Kyaw, or car headlight glare behind him, made worse by a wet or fogged windshield on the truck, may have concealed him.

And, again, if Kyaw was not headed toward the truck head-on, the front reflector is irrelevant.

Kyaw’s 21-speed bicycle appeared to be set at the gear combination that was as hard to pedal in as possible, indicating travel “at a fairly fast pace,” police report #5 said. On the other hand, if Kyaw was intending to turn left and was approaching a red light, it is also possible he was slowing down, or had even come to a stop.

The fifth Cambridge police report includes this statement but also indicates that the shifter for the rear derailleur was in the second-highest position, not the highest.

The discussion of Kyaw’s speed would have benefited from interviews with people who knew his riding style, if they could be found. There are many bicyclists who ride in high gear at a low cadence. On the other hand, he might have been strong and fast, yet still foolish enough to ride at night without a headlight. In this case, he would have been heading into an intersection with a major street against a red light at high speed. I consider that unlikely.

Still, all this brings up the issue of educating bicyclists. I’ve advocated for decades that institutions of higher education provide bicycling instruction to incoming students. Avoiding death or brain injury to even one student every couple of years would more than pay for this. Think of the wasted educational investment, and the loss of future alumni contributions. But I digress.

According to Cambridge Police Report #1, the truck driver “stated that he was traveling westbound on Mass. Ave. when he attempted to take a right turn onto Vassar St. [The driver] said that the light was green and his right directional light was on. Moments later, [he] said he felt the impact of something hitting his truck. He stopped and got out of his truck to investigate and observed that he had been in a collision with a bicycle.

This doesn’t indicate which way the driver was looking — not a very informative statement from him. Did the police ask?

According to the reconstruction report, MIT provided video that showed the truck did activate its right directional signal.

(As indicated in a comment with the article, the video did not show Vassar Street, so it didn’t show Kyaw’s approach).

The police reports say little about the condition of the truck other than that its brakes worked. Was its windshield clean? Were all the mirrors in good working order? Were the headlights aligned? Was the driver’s view ahead obstructed? Etc.

The Massachusetts State Police accident reconstruction report says almost nothing about the bicycle, but page 2 of the fifth Cambridge report describes the locations of scrapes and other damage to the bicycle. These are consistent with the truck’s striking the left side of the bicycle and dragging it on its right side. The front fork was bent to the right, suggesting that the bicycle was struck from the left — except that the front fork and wheel were crushed under the wheels at the rear of the truck’s cab. as shown in the still below from a television news report. I have labeled the locations of the bicycle — the saddle is facing the camera; of a shoe; and of where Kyaw lay following the crash. He had been removed by the time the video was shot.

Locations of bicycle, shoe and Kyaw following crash

Locations of bicycle, shoe and Kyaw following crash

The reports are incomplete in describing the bicycle. Of most importance, what was the condition of the bicycle’s brakes? Even when a bicycle has been damaged by going under a truck, it is possible to examine brake shoe and rim wear, and to determine whether a brake cable had frayed and parted. It is often possible to operate the brakes and determine whether they were in good adjustment.

The bicycle was an under $200 model sold through big-box stores, which are notorious for poor assembly of bicycles — here is the best description of it I could find online. It does have aluminum rims, which brake much better than steel rims in the wet, but how well was the bicycle maintained, and were the brakes working properly at the time of the crash? The police reports say nothing about this.

Though the Massachusetts State Police accident reconstruction report and vehicle inspection report really ought to be definitive on the topics they are supposed to cover, police reports which have not yet been released may possibly fill in some of the missing information.

I hope that my comments have been informative and helpful. — John S. Allen

(Update: please click on the link below to read Paul Schimek’s comments and my replies to them. Paul has suggested that Kyaw was approaching on the Massachusetts Avenue sidewalk. Based on further review of damage to the bicycle, I think that Kyaw may have been cutting the corner from right to left across the path of the truck.)

May 20, 2011

Response to City officials’ comments about Concord/Follen

Robert Winters has posted a comment (#3 here) to my post about bicycling issues on the May 16 City Council agenda. Robert quotes Assistant City Manager for Community Development Brian Murphy and Traffic, Parking & Transportation Director Susan Clippinger about Follen Street and Little Concord Avenue. Their response, by way of the City Manager, is addressed to the City Council at next week’s meeting.

Their response (again, in comment #3 here) addresses some of the issues with the Follen Street/Concord Avenue installation, and reflects some progress.

Serious design issues, however, will still remain:

  • The configuration still has the same blind corners.
  • Because of the location of the curb cut into the brick plaza, bicyclists traveling away from the Common must still swerve to the right, toward approaching motor traffic, to reach the curb cut at the crosswalk on the far side of Follen Street. Bicyclists entering from the brick plaza are still close to a wall which also obscures motorists’ view of them.
  • Motorists approaching on Follen Street still won’t have a stop sign — see this Google Street View — despite the blind corners.
  • The contraflow bike lane adjacent to wrong-way parking remains.
  • There is another blind corner at the Garden Street end of the pedestrian plaza, particularly for cyclists who continue toward the Radcliffe Quadrangle on the sidewalk (and many do, though that is inadvisable).
  • The “bike box” on Concord Avenue leads to more confusion than anything else, as described here. Also, many cyclists ride east on the north sidewalk, so they can access the plaza directly, posing a risk of head-on collisions with westbound cyclists and pedestrians at the blind corner between the sidewalk and the plaza.

Contraflow bicycle travel would be safer if parking were removed from one side of Follen Street — however, the public insists on using public street space for private car storage. As a bicycling advocate and former Cambridge resident who owned a (rarely used) car and had no other place to park it than the street, I can see both sides of this issue. It is not going to go away. The people who laid out Cambridge’s streets could not foresee the deluge of private motor vehicles that would descend on the city, and had no plan either to accommodate it or to forestall it.

I do think that a very significant safety improvement could be made without removing parking, by reversing the direction of one-way motor traffic on Follen Street and Little Concord Avenue. Then cyclists headed toward the blind corner would be going in the same direction as motorists. The motorists would be going very slowly here, and cyclists could easily merge toward the center of the roadway. A curb cut into the plaza in line with the center of the roadway would avoid cyclists’ having to swerve right. This curb cut would lead cyclists traveling toward the Common to the right side of the street.

A contraflow bike lane could then be installed on the south side of Little Concord Avenue, but it would still be adjacent to wrong-way parking. I’d rather see shared-lane markings far enough from parked cars to allow a motorist to start to exit a parking space without running head-on into a cyclist or forcing that cyclist into oncoming traffic. One-way, slow streets where bicyclists are allowed to travel contraflow are common in Germany, without bike lanes, and research has demonstrated their safety.

As to Murphy’s and Clippinger’s comments:

Motor vehicle volumes on the street are very low and most drivers are ones who live there and use the street regularly. The contraflow lane was installed to improve safety for cyclists by creating a dedicated facility for them to ride in and through the presence of pavement markings to remind motorists that bicyclists are traveling there.

The low motor-vehicle volume argument is an example of what I call “bean counter” safety analysis. I have heard the same argument before from Cara Seiderman, in connection with the wrong-way contraflow lane on Scott Street. This approach offers cyclists and motorists only statistical comfort, leaving them defenseless against actually preventing a crash through their own actions — as in “well, I can’t see over the SUV parked in front of my car, but probably no cyclist is coming so I’ll pull out.”

The bike lane does serve as a buffer to help prevent collisions between cars and other cars, but it doesn’t pass the test of preventing collisions between cars and cyclists. The comforting words “dedicated facility” don’t actually describe how it works in practice. Reminding motorists that bicyclists are traveling in the bike lane doesn’t count for much if the motorists can’t see the bicyclists.

Clippinger describes a safety analysis which looked at generalities about traffic volume. The claim that the dedicated facility was installed to improve safety may describe intention, but it does not describe either the design, or the outcome. This is a crash hotspot, remember. I have described design issues, and some solutions that look rather obvious to me. The city, as usual, installed a boilerplate bike lane design without much insight into whether it actually would be functional and safe.

November 3, 2010

Specific issues with Western Avenue project

In this post, I’m going to examine some of the drawings of its Western Avenue project which the City of Cambridge has provided.

All of the illustrations below are from the City’s conceptual design booklet.

Western Avenue concept drawing

Western Avenue concept drawing

The cars shown parked at the left are real cars, in the original photograph that was modified to show the conceptual design. Typical sedans are about 5 1/2 feet wide, not counting the side-view mirrors, but common light trucks are as much as 6 1/2 feet wide. Big trucks and buses can be 8 1/2 feet wide.

The cars shown parked at the right are drawings added when the photo was modified. All of them are micro-cars, very much smaller than the cars on the left — only about 4 1/2 feet wide.

Bicyclists complain about “door zone” bike lanes — where opening car doors pose a threat. On the other hand, the door zone serves an important function. A motorist can open the car door without its protruding directly into the path of motor traffic, and can walk around the car.

In the drawing below, I have copied the nearest car in the original drawing into each travel lane. This drawing shows too little clearance between parked vehicles and moving ones to allow motorists safely to walk around to the street side of their vehicles or open the doors. The right lane as shown is especially tight, even with micro-cars parked on the right and ordinary sedans in the travel lanes — though Western Avenue is a designated bus and truck route.

Western Avenue concept drawing, modified

Western Avenue concept drawing, modified

To show how wide the left lane is at present, the white line in the foreground replaces the gray patch that is dimly visible in the original drawing, covering up the location of the present lane line.

The parts of the illustration that are from the original photo are to scale — including the cars I have copied into the travel lanes. The drawn-in elements are conceptual, and some are not to scale.

The drawing below, also from the City, is dimensioned, showing a 36-foot wide roadway. The elements are to scale: 10.5 foot travel lanes, 7-foot parking lanes and mid-sized cars 6 feet wide, not counting the mirrors — like a a Ford Taurus. This drawing shows more room between vehicles than the right lane in the photo, but on the other hand, the parked cars are tight against the curbs, and no trucks or buses are shown.

Cross-section of street with cycle track

Cross-section of street with cycle track

Now let’s look at an overhead drawing, which shows a typical treatment at an intersection.

Western Avenue at Jay Street

Western Avenue at Jay Street

Let’s put more cars and some bicyclists and pedestrians into the picture. I’ve put three bicyclists on the blue strip which represents the cycle track. Two are headed with traffic and one is headed opposite traffic. (Off-street facilities encourage two-direction traffic, and this is particularly so on a one-way street where there is no opposite-direction paired street conveniently nearby.) There also is a group of pedestrians standing on the bulbout before the intersection. Excuse me if the bicyclists and pedestrians look like ants, I’m no Picasso.

Pedestrians and parked cars conceal  right-way bicyclists from drivers of cars A and B, increasing the risk of a “right hook” collision. Also, Car B  is blocking the right-hand travel lane. Such blockages will increase congestion. The more bicyclists, the more often turning motorists will have to wait in the position shown. At present, motorists can keep moving as they prepare to turn right, because they can merge behind a bicyclist before reaching the intersection.

Car C in the drawing must wait far back from the intersection, what with the separate sidewalk and cycle track. Then, on reaching the intersection, as shown in the illustration below, the car must block the cycle track as the driver scans for traffic. If more than one car is in line, both the sidewalk and the cycle track will be blocked at the same time.

Western Avenue at Jay Street, cycle track blocked

Western Avenue at Jay Street, cycle track blocked

Presently, without the cycle track, this kind of blockage happens only for the sidewalk. It is more troublesome and hazardous for bicyclists than pedestrians, because bicyclists are faster, and farther away when the driver must first see them, and can be hidden by buildings or by pedestrians on the sidewalk. The crash rate for wrong-way cyclists on cycle tracks like this one is very high — research in Finland, Sweden and Germany has shown it to be about 10 times as high as for right-way travel on the street. Right-way travel on a cycle track located, like this one, behind parked cars, and with unsignalized intersections and driveways, has been shown only two or three times as hazardous.

There is also a much greater risk of collisons with pedestrians, and with other bicyclists, than when riding in the street. This cycle track has about 6 feet of width where bicyclists are clear of car-door hazards or plantings — very substandard for a two-way facility.

There is a question what the wrong-way bicyclists will do when they reach Franklin Street and the cycle track ends. Most likely, they will go up onto the sidewalk or ride opposite traffic in the bike lane.

Finally, let’s look at the intersection of Western Avenue and Memorial Drive. At present, Western Avenue has four travel lanes approaching the intersection.  The rightmost lane is a right-turn-only lane which the City describes as underutilized. I agree with that description — even in the evening rush hour, I have been able to filter forward to the intersection on my bicycle in that lane.

The City proposes to change that lane into a cycle track, so right turns are made from the next lane to the left. In this connection, I question the City’s conclusion that its plan will not increase congestion. In the evening rush hour, traffic already queues on Putnam Avenue and Memorial Drive, all the way back to River Street. Even one vehicle waiting to turn right, while bicyclists overtake on the right, will block all other vehicles in the lane behind it. This is aside from the issue of institutionalizing the “right hook” — placing all responsibility for bicyclists’ safety on the motorists, and stripping away bicyclists’ defense of merging into the line of right-turning traffic.

Western Avenue at Memorial Drive, conceptual drawing

Western Avenue at Memorial Drive, conceptual drawing

I suggest instead that bicyclists be encouraged to travel along the left side of the right-turn lane, by means of shared-lane markings and signage, or better, if there is room, a through bike lane.

The question remains of how to handle opposite-direction bicycle traffic. It does not admit of an easy answer.  At this point, I’m most inclined to try to address it on River Street.

And, I’ll add: the sacredness of on-street parking is the issue that makes the problem insoluble. If parking could be removed form one side of Western Avenue, a contraflow bike lane would be an option.

There is no such issue on River Street, because there are many parallel streets in Cambridgeport that allow travel in the opposite direction.

Signing off…

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