Cambridge Civic Journal Forum

February 21, 2017

Black ice blindness

Snowmelt drains across "protected" bikeway on Massachusetts Avenue in Cambridge

Snowmelt drains across “protected” bikeway on Massachusetts Avenue in Cambridge

The photo is of a stretch of barrier-separated bikeway recently installed on the north side of Massachusetts Avenue between Sidney Street and Douglass Street in Cambridge. The headline of the February 17, 2017 Boston Globe article with this picture is “Snowbank becomes accidental hero for area cyclists”.

But — the shiny area in the bikeway is meltwater from said snowbank. When the temperature drops, the water freezes into a sheet of black ice. The usual drainage techniques don’t work here because, if you will excuse me for belaboring the obvious, the “hero barrier’ is uphill and water runs downhill. I discussed bikeway drainage issues in more detail recently in a post on another blog and years ago in connection with the 9th Avenue bikeway in Manhattan. Just to make it clear, I do have  nice things to say about other features of the 9th Avenue bikeway.

Neither Steve Annear, author of the Globe article, nor anyone quoted in it, makes any mention of the black-ice problem. They are all enthusiastic about the snow-barrier.

From the article: “I like this snowbank-protected cycle track,” Ari Ofsevit, a local cyclist, said on Twitter.

Ari is more than just a “local cyclist”. He widely, imaginatively and thoughtfully discusses transportation improvements his blog. I usually agree with him, except when he turns a blind eye to problems with barrier-separated on-street bikeways.

The article cites Joe Barr. Director of Traffic, Parking, and Transportation for the City of Cambridge:

Barr acknowledged that the snow mound separating the bike lane and the road has offered a sense of protection to cyclists, but he said it could also be masking damage to the base of the flexible posts.

“We won’t know that until we get some more melting. But it certainly looks good on the street,” he said.

And Richard Fries, Executive Director of the massachusretts Bicycle Coalition, commented:

It’s great. It won’t last that much longer, but it does help to hammer into people’s heads [road] patterns and driving habits,” he said. “Because it’s there, it makes the existing bike lane more visible to drivers and more prominent.

Segregation promotes a sense of entitlement on the part of the majority group –in this case, motorists. How do I explain to horn-honking motorists that I have to ride my bicycle in “their” travel lane, now narrowed to make room for the barrier, to avoid crashing on a sheet of black ice?

Or for that matter, to travel at my usual 15 miles per hour so I’m not stuck behind a cluster of bicyclists who are traveling at 8 miles per hour?

Or to avoid being right-hooked and crushed under the back wheels by a right-turning truck where the bikeway ends at Douglass Street?

Just asking.

December 2, 2016

Where did the Amanda Phillips crash happen? And why?

Filed under: Cambridge,cycling,Deaths — Tags: , , , , , — jsallen @ 10:47 am

In a previous post, I stated that Amanda Phillips’s fatal crash occurred outside Inman Square, not in the Square.

An examination of news photos and a Google Street View establishes the precise location — 1423 Cambridge Street, just west of the Square.

The Google Street View

Boston Globe article with photo: note the blue recycling bin peeking out from behind the trash barrel, the distinctive leaning tree, and the ambulance parked on Hampshire Street in the background.

The Cambridge Patch has an even better photo.

This evidence establishes that Phillips had exited Inman Square. It has been reported that she rode off the sidewalk. That would place her in the same precarious situation as with the bike lanes exiting the Square in a “Peanut Roundabout” proposal advanced by the Boston Cyclists Union.

I also commend readers to Paul Schimek’s examination of factors which led to the crash.

December 1, 2016

A Peanut in Inman Square?

Inman Square is a difficult, pre-automotive, cramped, often congested, diagonal intersection. Thoroughgoing safety and traffic-flow improvements are not possible, short of tearing down buildings to create more travel space, or an expensive grade separation.

Anne Lusk, Visiting Fellow at the Harvard School of Public Health and a relentless advocate for on-street barrier-separated bikeways, has promoted a proposal for a “peanut roundabout” as a solution to the problems with Inman Square.

A grade separation was built long ago, farther west where Cambridge street runs between Harvard buildings. Though Lusk works at Harvard University, Inman Square does not adjoin the campus, and the political and financial resources of the University evidently don’t come to bear on the Square’s problems.

A Web page from the Boston Cyclists Union describes the “peanut roundabout” concept which Lusk is promoting for Inman Square. Here’s a conceptual drawing from the Web page:

"Peanut Roundabout" concept for Inman Square

“Peanut Roundabout” concept for Inman Square

I do think that the peanut roundabout concept is clever in itself. By eliminating traffic signals, this design might improve traffic flow.

— except for problems for bicyclists and pedestrians.

In the conceptual drawing on the page, to continue across the square in the same direction, bicyclists are directed to follow a circuitous route on separated bikeways, subject to right-hook risks, and turn sharply left after waiting at locations where they would block other bicyclists bearing right. There is no waiting area other than the narrow bikeway in which the bicyclists approach. The page describes the crossings as “European-style protected crossings” — but they aren’t. Strictly speaking, in traffic engineering, “protected” means that conflicting movements are prevented by traffic signals. No traffic signals are shown in the conceptual drawing. Four of the six crosswalks are raised, and these would slow motorists, but there are no waiting areas that would make it clear whether bicyclists will be turning across motor traffic or proceeding straight.

All in all, I cannot imagine how this concept would work for bicyclists or pedestrians without traffic signals for the crosswalks. Signals, though, would result in more motorists in the roundabout blocking other motorists’ travel in the roundabout. The conceptual drawing avoids raising this issue. Few vehicles are shown in the roundabout, inconsistent with the many in the connecting streets.

The conceptual drawing shows door-zone bike lanes leading to and from Inman Square at every approach. Earlier this year, cyclist Amanda Phillips was killed when the opening door of a parked vehicle flung her under a truck — the incident which led to calls for redesign of the Square. She was, however, not in the Square: she was had left the Square. (Identification of the crash location) It has been reported that she was exiting the sidewalk just before she was doored — so, she came from behind the vehicle whose door opened in front of her. What lessons from this crash have informed the proposed peanut design? Apparently none. The bike lanes shown at exits from the Square place bicyclists in the same hazardous situation as Phillips: emerging from behind parked vehicles, rather than where they might be visible with a driver’s-side mirror or a glance over the shoulder.

The page claims that “[s]uch a design could radically improve traffic flows, safety, and the community fabric of crash-prone Inman Square.” It would be useful in evaluating proposals, and claims like these, to have  a traffic capacity and flow analysis, and a crash study.  Instead, on the Web page, there is a list of claimed advantages, with no mention of potential problems and no analysis.

My overall impression of this design as a bicyclist, in addition to the concerns about safety, is that while it might increase appeal to bicyclists who are fearful of riding in mixed traffic, delays will be such that bicyclists who want to get where they are going will ride in the motor traffic. And let’s hope that they understand that safety would require them to ride in line with the motor traffic rather than keeping out of its way, as the designated routes strongly imply to be the key to safety.

The City of Cambridge has put forward two other proposals. A  “bend Cambridge Street” proposal is shown in the image below. Traffic on Hampshire Street would travel straight through, and traffic on Cambridge Street would zigzag. A similar “bend Hampshire Street” proposal is more or less a mirror image of this one. These proposals are similar to what has been done with Union Square in Somerville and at Lafayette Square (the intersection of Main Street and Massachusetts Avenue) in Cambridge.

City of Cambridge "bend Cambridge Street" proposal

City of Cambridge “bend Cambridge Street” proposal

The “bend” proposals include traffic signals and require bicyclists and motorists to make left turns. I do think, however, that the blue space in the “bend Cambridge Street” proposal might include bikeways, so  bicyclists on Cambridge Street could continue straight where the street bends left toward the first traffic light and then re-enter Cambridge Street by crossing Hampshire Street at the second traffic light rather than by turning left. (This would not be practical with the “bend Hampshire Street” proposal, because bicyclists would have to turn left across Hampshire Street to enter the blue space). The drawing below shows my proposal. Bicyclists would follow the red arrows.

Bend Cambridge Street proposal with shortcut bikeways

Bend Cambridge Street proposal with shortcut bikeways

The blue areas also might include useful social space — unlike the peanut roundabout proposal, where the extra space would be in the middle of the street.  The two traffic lights in the Bend Camridge Street proposal would, to be sure, increase delay for motorists. Bicyclists following the red-arrow route would encounter only one traffic light.

I’ll admit that I don’t have any more thoroughgoing answers to Inman Square’s problems other than the two I’ve already mentioned — tearing down buildings or creating a grade separation — which are not going to happen. I’ll be trying to think of other possibilities, and please, you do also.

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March 31, 2015

Web page includes two videos of Cambridge bicycle infrastructure

Please check out this Web page,with two of four videos illustrating exciting new developments in Cambridge bicycle infrastructure. Can you identify the locations?

Exciting new technology demonstrated at a Cambridge bicycle facility.

Exciting new technology demonstrated at a Cambridge bicycle facility.

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February 21, 2015

Plowing, or sweeping under the rug?

The photo of the Western Avenue bikeway with this post has been making the rounds in bicycling advocacy circules, accompanied with praise for Cambridge’s plowing it.

You can praise the plowing all you like, but in terms of safety, it amounts to window dressing, distracting from problems which would not exist except for the segregated bikeway: with the snowbanks, bicyclists and motorists are both going to have to come nearly to a complete stop at every crossing to see each other in time to avoid collisions. Streets, on the other hand, even narrowed by snow, are wide enough that the cyclists can ride away from the edge, and motorists can poke out far enough to see approaching traffic without the risk of collisions.

The bikeway is also too narrow for one bicyclist safely to overtake another. The street is wide enough for anyone — bicyclist or motorist — to overtake a bicyclist, though maybe not always wide enough for one motorist to overtake another, what with the snow. It is narrower too because of the space that was taken out of it for the bikeway. The street also most likely is clear down to pavement within a day or two after a snowfall, and it is crowned so meltwater drains to the curbs. The bikeway is going to be a sheet of ice if there are thaw/freeze cycles, unless there is a very heavy application of road salt.

Bicycling is already difficult enough in winter without the added difficulties and hazards imposed by this bikeway.

western_avenue_winter

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June 24, 2014

Starts and Stops, mostly stops

I’m commenting on the “Starts and Stops” article which appeared in the Boston Globe on Sunday, June 22, 2014.

That’s behind a paywall. You may need to log in as a Globe subscriber to see it. (I’m one, but if I recall correctly, there’s a limited number of views till the paywall descends). You can also log in from home in the Boston area using a library card number.

The Globe article describes a bicycle-specific traffic signal on Western Avenue and makes the claim:

The Western Avenue signal is timed so that cyclists get a green light a few moments before their vehicular counterparts headed toward Memorial Drive; that way, cyclists have several seconds of a head start to get out ahead of the cars and become more visible to motorists, especially motorists turning right who may not think to look for cyclists approaching on their right side.

That only works if bicyclists happen to be waiting when the light changes. Otherwise, according to the description in the article, there is a right-hook conflict, with motor vehicles turning right across the path of bicyclists approaching in their right rear blindspot. I haven’t checked out the installation yet; I’ll be back in a couple of weeks with more detail.

The article goes on to say:

Additionally, signals like this one address one of the biggest gripes motorists have with bike riders: that they’re constantly running red lights. For cyclists, there can be no confusion whether they’re expected to stop at a red light when that light shows a little bicycle. Many engineers believe that when cyclists are assured that a traffic light is targeted at them and designed to protect their safety, they’re much more likely to wait for their rightful turn to proceed through the intersection.

Here’s the photo which the Globe posted with the article.

New bicycle-specific traffic light on Western Avenue

New bicycle-specific traffic light on Western Avenue

Wishful thinking. Normal traffic lights also apply to bicyclists. Do we need our own very special, and eexpensive, signal just so we will feel pampered? The traffic light shown in the photo, by the way, isn’t at Memorial Drive. It is at Putnam Avenue, a block earlier. Because the photo doesn’t show the installation which the article describes, I’m not entirely clear about the details.

It was previously possible for bicyclists to approach Memorial Drive in the through lane and enter on the normal green light — or sensibly, though in violation of the specifics of traffic law, at the left side of a right-turn lane lane, and also enter on the normal green. Now, bicyclists and right-turning motorists are, at least as described in the article, forced into a right-hook conflict.

Please, who are the unattributed “many engineers”? Opportunistic bicyclists and pedestrians, motorists too — commit traffic-signal violations because they get annoyed with waiting. Compliance improves if a traffic-light system is designed to minimize waiting time. This one doesn’t, and right-hook conflicts don’t protect anyone’s safety.

I am about to attend the summer meeting of the National Committee on Uniform Traffic Control Devices (NCUTCD), where I sit on its Bicycle Technical Committee. Two proposals currently before the Committee, in experimental status, are special bicycle traffic signals, and right-turn lanes with a bicycle lane inside their left side. I would have hoped that Cambridge had submitted a formal Request to Experiment from Cambridge for either of these proposals — which would add to the knowledge base, and confer immunity from legal liability — but I’ve seen none. I should have. The Federal Highway Administration calls on the NCUTCD to review them.

Oh, and also — in the Globe’s photo, it looks as though a car is sitting in the bikeway.

More to come.

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April 16, 2014

About Bicycling on Hampshire Street

I have posted a video I shot on Hampshire Street in Cambridge during an organized group ride, in the middle of the day on a weekday.

This blog doesn’t llet me embed the video in the page, soclick on the link underneath, then the little four-way arrow under the image to view the video in glorious full-screen high definition.

Is This Two-Lane Street Wide Enough? from John Allen on Vimeo.

The stretch of Hampshire Street in the video was the subject of a study conducted by the City of Cambridge about the effect of various lane stripings on cyclist behavior, a study which I have reviewed. The study concluded that bike lane striping led bicyclists to ride safely, farther from parked cars. My review showed that statement to be inaccurate, due to misrepresentation of bicyclists’ distance from the parked cars. The “safe” line of travel was still deeply in the door zone. Another reviewer, Wayne Pein, has reached the same conclusion.

My video shows cyclists riding too close to parked cars, consistent with the study once the numbers have been corrected — all the more distressingly because most of the cyclists in the video are middle-aged or older and have years of experience. For the most part, however, their experience has been in rural areas and outer suburbs rather than in the city.

I think that it is fair to ask:

  • whether the striping of the street with bike lanes benefits bicyclists — or motorists, by getting bicyclists out of the way — or not motorists, because of the resulting conflicts at intersections bring motor traffic to a complete stop rather than only down to bicycle speed;
  • whether the parallel parking on both sides of this important through street — at all hours, even during the day when it is only half-occupied — is an appropriate use of public space — though, as I say in the video, the people who live here vote here. Another potential solution would be to narrow each sidewalk by a couple of feet…but that would require more construction work.
  • whether these cyclists understand how to ride as safely and cooperatively as possible on such a street (NOT!).

My video also bears on the proposed reconstruction of Beacon street, in Somerville. Beacon Street is the extension of Hampshire street, and has the same profile and character. There have been different suggestions for Beacon Street, including widening it to make better bike lanes; removing parking on one side; and construction of a “cycle track” — separate bikeway — on one side, between parked cars and the sidewalk, and on the other side, actually a bike lane behind a sloping curb which is supposed to be mountable by bicycles. A post on the BostonBiker blog offers my comments on Beacon street.

[Note: I have a shorter blog post about Hampshire Street on bostonbiker.org. Hampshire Street and the City’s study are a Cambridge issue, not only a bicycle issue. I have posted in both forums because they serve different audiences.]

December 16, 2013

Update on the Copenhagen Wheel

In a post in this blog from 2011, I reported on a product under development at the MIT Senseable Cities Laboratory, the Copenhagen Wheel. It provides an electrical power assist to a bicyclist.

The motor and batteries are contained entirely in the rear wheel. The Wheel can be controlled through a Bluetooth connection from a smartphone on the handlebar, so there is no need for wiring. Various smartphone apps can report on speed, distance, state of battery charge, exposure to air pollution etc.

Copenhagen Wwheel promotional video shows bicyclists riding in the door zone

Clip from Copenhagen Wheel promotional video shows bicyclists riding in the door zone

I had a serious concern  in 2011, that the Wheel was designed to switch from motor mode to generator mode at 12 mph. In other words, if you tried to go faster, you couldn’t: it would feel as if you were pulling a huge trailer. 12 mph is slower than many bicyclists would usually ride and could be hazardous if there is a need to sprint across an intersection before the traffic signal changes, to outrun a chasing dog, etc.

Development of the Wheel has continued, and readers deserve an update. The Wheel is now going into a production, licensed to a company called Superpedestrian. Maximum power is now 250 watts, top speed 15 mph in Europe; power 350 watts, top speed 20 mph in the USA — reflecting legal limits. (15 mph, though, is still much lower than a desirable sprinting speed, and many bicyclists can easily sprint at more than 25 mph.) Pedal power is proportional to torque (whether cadence-sensing, I don’t know — torque sensing alone would favor slow cadence and hard pushing. There is a derailleur option which alters the relationship between pedaling torque and torque at the wheel, so this becomes a more serious issue.) Some technical specs are online on the manufacturer’ site.

Placing the entire power unit in the wheel makes retrofitting to an existing bicycle easy, but my friend Osman Isvan, who studies electrically assisted bicycle technology, questions the Wheel concept, or any electric motor in the wheel. He says that a mid-drive system with a small, high-speed motor powering through a reduction drive to the crankset is better, because then the motor can be lighter and more efficient. In case you would like to get technical, Osman has an article, “Power Optimization for the Propulsion of Lightweight Vehicles,” where he addresses this issue, among others. The Wheel’s motor may in fact use a gear reduction drive, unlike most in-wheel motors, though it almost certainly doesn’t benefit from the ability to maintain nearly constant motor speed with the motor (like the cyclist’s feet) ahead of derailleur gearing or an internal-gear rear hub.

One thing that really caught my eye was the disconnect from safe bicycling practice in the company’s promotional video.

The first photo (above) in this article is from the video and shows bicyclists riding in the door zone of parked cars, at speed. That occurs in the video at 0:45 and 1:45.

At at 0:21 and again at 1:39, the Wheel is demonstrated by a bicyclist riding the wrong way on a one-way street, and where a parked car could pull out, but the next parked vehicle hides the bicyclist from the driver, who is on the curb side.

Bicyclist riding wrong way in copenhagen Wheel promotional video

Bicyclist riding wrong way in Copenhagen Wheel promotional video

There’s this shot of unsecured baggage including a (virtual?) electric guitar which hangs way out past the end of the handlebar — a large virtual amplifier is on the rear rack.

Unsecured baggage..

Unsecured baggage..

And then there’s this shot of a man illegally carrying a (fortunately virtual) small child on his shoulders, and another child sitting facing backwards sitting crosslegged on some kind of platform. The law more or less everywhere in the USA says that children are to be carried only in seats designed for the purpose. Massachusetts law says that the children must wear helmets. Anyone familiar with Our Fair City will know that this clip, like many in the video, was shot on our own Paul Dudley White Bicycle Path.

Illegal if the kids weren't virtual...

Illegal if the kids weren’t virtual…

This carelessness in promotion sets me to musing about what we have ahead of us as the increased speed potential (even if only 20 mph) of electrically-assisted bicycles collides with the kind of underdesigned bicycle facilities — essentially sidewalks — which Cambridge is building — a trend now spreading to Somerville and Boston. We’re not talking superpedestrians here, we’re talking bionically enhanced — but not skills-enhanced — bicyclists on bikeways which could only be safe at pedestrian speeds.

Allow me to predict that over the next decade, the products of bikeway visionaries and bicycle technology visionaries are going to come together in some rather interesting but also disturbing ways!

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