Category Archives: Crashes

Truck side skirts: reliable way to prevent cyclist fatalities?

No, not reliable. And they are also supposed to confer an aerodynamic advantage. Some do, some don’t.

Some have a smooth surface which can deflect a cyclist. That is still no guarantee that the cyclist will escape serious injury or death. Other side guards are only open frameworks which can catch and drag a bicycle. A lot of what I have seen is little more than window dressing.

The side guard in the image below from a post on the Treehugger blog has no aerodynamic advantage and could easily guide a cyclist into the rear wheel of the truck.

Photo of truck side with guard from Treehugger blog.

Photo of truck side with guard from Treehugger blog.

A cyclist can easily go under the side guard shown in the image below, from a Portland, Oregon blog post. A cyclist who is leaning against the side guard is guided into the sharp edge of the fender bracket and fender, and the front of the turning wheel, which can pull the cyclist down. There is another wheel behind the one in the photo.

Side guard on City of Portland, Oregon water transport truck

Side guard on City of Portland, Oregon water transport truck

The side guard on a Boston garbage truck in the photo below — my own screen shot from the 2013 Boston Bikes annual update presentation — is only an open framework which could easily catch and drag a bicycle.

Side skirt on City of Boston garbage truck

Side skirt on City of Boston garbage truck

A truck which is turning right off-tracks to the right. A cyclist can be pushed onto his/her right side, and goes under, feet to the left, head to the right. On the other hand, if an overtaking truck contacts the left handlebar end, or if the right handlebar end contacts a slower or stopped vehicle or other obstruction, the handlebar turns to the right and the cyclist slumps to the left, headfirst.

To be as effective as possible for either aerodynamics or injury prevention, side guards must cover the wheels. Though that is practical, none of the ones shown do.

But no practical side guard can go low enough to prevent a cyclist from going underneath. The side guard would drag  at raised railroad crossings, driveway aprons, speed tables etc. Even if the side guard did go low enough, it would sweep the fallen cyclist across the road surface, possibly to be crushed against a parked car or a curb.

Fatalities have occurred when cyclists went under buses, which have low side panels — but the wheels are uncovered. The Dana Laird fatality in Cambridge, Massachusetts is one example. Ms. Laird’s right handlebar end is reported to have struck the opening door of a parked vehicle, steering her front wheel to the right and toppling her to the left.

Dana Laird fatality, Cambridge, Massacchusetts, 2002

Dana Laird fatality, Cambridge, Massachusetts, 2002

The bicycling advocacy community, as shown in the blog posts I’ve cited, mostly offers praise and promotion of sub-optimal versions of side guards, a measure which, even if executed as well as possible, offers only a weak, last-resort solution to the problem of bus and truck underruns.

Most of the comments I see on the blogs I linked to consider it perfectly normal for motor traffic to turn right from the left side of cyclists, and to design infrastructure — bike lanes in particular — to formalize this conflict. The commenters also would like to give cyclists carte blanche to overtake close to the right side of large trucks, and place all the responsibility on truck drivers to avoid off-tracking over the cyclists.

Cyclists are vulnerable road users, but vulnerability is not the same as defenselessness. It is rarely heard from today’s crop of bicycling advocates, but a cyclist can prevent collisions with trucks and buses by not riding close to the side of them. There’s a wild contradiction in playing on the vulnerability, naiveté and defenselessness of novice cyclists to promote bicycle use with measures — particularly, bike lanes striped up to intersections — which lure cyclists into a deathtrap. Regardless of whoever may be held legally at fault in underrun collisions, cyclists have the ability to prevent them, and preventing them is the first order of business.

Want to learn how to defend yourself against going under a truck? Detailed advice on avoiding bicycle/truck conflicts may be found on the Commute Orlando Web site.

Additional comments about the political situation which promotes underrun collisions may also be found on that site.

Ian Cooper comments on the C&O Towpath

Cyclist Ian Cooper offers a report on the C&O canal towpath, which I have mentioned in a previous post. Supreme Court Justice William O. Douglas deserves a lot of credit for preserving the canal as a park, but as Ian reports, it does not make the grade as a bicycle facility.

Ian Cooper with Trail-a-Bike rig on the C&O towpath trail

Ian Cooper with Trail-a-Bike rig on the C&O towpath trail

Aside from the issues of safety and of priorities which Ian raises, do the parts of the path which are “paved” with pebbles the size of golf balls meet the National Park Service’s criteria to prohibit cyclists from parallel roads, introduced into the current transportation bill in Congress?

An article in the Pittsburgh Tribune-Review newspaper seconds some of Ian’s comments, while indicating that improvements are in the works. The effectiveness of the improvements is certainly open to question: more gravel will not eliminate dropoffs or necessarily provide a good or durable riding surface. The article includes the photo below.

Rough conditions on the C&O towpath trail

Rough conditions on the C&O towpath trail, Paul Christensen photo for the Tribune-Review

An online article by a bicycle tourist also reports some difficult conditions on the trail.

Ian says about that article:

The first image on the left of the page shows a little of how muddy it can get, though it can be worse than this when the path gets very narrow and bumpy. This is a different area of the trail (farther north than my ride), and again this is very wide and non-grassy in comparison with some of the trail south of Harper’s Ferry and Point of Rocks, MD. The author tells how safety is a real issue on the trail due to the bad condition of the surface.

In both the above images, the wide trail allows you to choose a path through the mud. This isn’t always the case in the part my daughter and I cycled. Sometimes you just have to stop and walk. Sometimes you get no warning, hit a pothole or a mud patch and have to rely on skill to maintain control.

Here are Ian’s comments on his own ride:

I know the C&O well. Here on the Maryland side it’s not paved, and I think anyone doing more than 10 mph on it would be taking a grave risk. I cycled with my daughter from DC to Harper’s Ferry June 2nd – 3rd, 2011 with my daughter on a Trail-a-Bike behind me. I will never use it again, as the National Park Service has stated that it must remain unpaved, as it is to retain its historical attributes as a canal towpath. The only reason I didn’t give up on using it during that trip is that I have a lot of experience cycling in winter conditions, so I had confidence that I could counter-steer and retain balance during times when the bike lost traction in the mud. Also, we were heading north, so we were cycling on the canal side of the trail, where the drop-off was only 10ft. I dread to think what might happen if a less confident or less skilled cyclist lost control going southward and fell into the river.

We averaged 5mph. On regular roads, I would have done the trip in less than half the time (in part because the road goes pretty much straight there, while the ‘so-called’ multi-use trail takes a dog-leg approach alongside the river). Also, this trail is overgrown with weeds, is ‘paved’ with loose pebbles the size of golf balls, and is 4 ft wide in places with mud patches and 10+ft drops on each side. In my view it is the worst bike trail I’ve ever seen and is literally a death trap for cyclists (which is presumably why bike trail advocates avoid referring to it as a bike trail). Sadly, most so-called bike infrastructure is poorly designed, poorly implemented and lacking in funding for maintenance. I have yet to see a bike trail or bike path that is well designed, well implemented and well maintained. Until I do see such a thing, I am 100% against such follies.

The photo below was taken around 12 noon on June 3 somewhere near White’s Ferry and is the only image I have showing the actual trail. It shows what should be considered a ‘good’ part of the trail in this area – this part is wide, relatively flat and has only a gentle slope away to the canal on one side. As you can see, even though there’s perhaps 8ft of trail, most of it is grassed over and there’s only two thin tracks of usable surface. Sometimes the trail gets so treacherous that the wet and slippery grass in the middle becomes the safest place to ride.

A better section of the C&O towpath trail

A better section of the C&O towpath trail

The C&O has few road crossings, it’s true. But if you use it in May or June, before the flood season is completely over (and presumably before any yearly maintenance is carried out before the summer season), you see it at its worst, when it is difficult just to maintain control of the bike. At some points, especially the stretch between Seneca and Point of Rocks, MD, it is quite literally frightening. In many places the trail is very narrow, it has a steep ten foot drop on one side to the old canal, and a steep twenty foot or more drop on the other side to the river (sometimes both at the same time). In May and June, the trail is so overgrown that stinging nettle bushes often thrust out into the trail. The trail is filled with pebbles and rocks, and overgrown grass and stinging nettles sometimes make all but a section between 6 and 12 inches wide unusable. This thin section can be muddy, it can change from dry to wet very quickly, it can be deeply rutted from use by previous cyclists, and other parts can be washed out so badly that cyclists can experience sudden potholes. It is extremely treacherous.

In my view, this stretch of the C&O Canal towpath should be closed as a multi-use path as its lack of adequate maintenance means that it is only a matter of time before a cyclist or a runner gets killed on it.

Why this crash?

The fancy, expensive bicycles and racing clothing are not matched by these cyclists’ bike handling skills.

If you play the video through to the end, you will see that the wheel touch broke 4 of the 8 spokes on the right side of the boutique 16-spoke front wheel.

Detailed explanation:

  1. Boutique wheel, few spokes, spokes necessarily overtensioned, big gaps for things to get in between them.
  2. Rider ahead merged left and slowed (notice backpedaling), oblivious to riding in tight group.
  3. Tri bars and no brake there.
  4. Overlapping.
  5. Spokes broke against QR handle. At this point overlap was by more than half a wheel.
  6. Still a good recovery.
  7. Inability to steer due to unstable front wheel and to need to move hands position to brakes — cyclist heads for ditch.
  8. Attempt to brake on warped front wheel locked the wheel.

Some commenters on the YouTube post have pointed out that the cyclist who crashed was wearing a sleeveless jersey and not wearing socks. This clothing is characteristic of triathletes — who don’t ride in groups while racing and are less likely to learn group riding skills than are road racers. Another point about clothing is that the cyclist wasn’t wearing cycling gloves. He broke his fall with his hands on gravel. Ouch.

A Cyclist Signs Up for Advanced Driver Training

What was an avid cyclist doing in a place like this?

I like to ride my bicycle but sometimes I have to drive.

Over 40 years ago on dirt roads and snow in Vermont, I learned to steer into a turn; to manage the situation when a car loses traction, rather than to blank out or panic.

I shot the video above recently, in a class with hands-on driver training which goes well beyond that. All of the instructors are racers. They test the limits of traction at every turn on the racecourse. But here, they are teaching skills for crash avoidance on the road.

My son took the class with me. He had taken a conventional driver training course and already had his driver’s license, but he had no experience handling a car at the limits of traction.

The InControl course begins with a classroom lecture. Our instructor, Jeremy, explained that driver training is broken in the USA: that over 40% of new drivers have a crash within the first two years; 93% of crashes result from driver error and so, are preventable. He also explained that he would be teaching about steering, braking, hazard perception and avoidance.

Jeremy handed a quiz sheet with 16 questions to check off, true or false. We were told to hold onto our quiz sheets because we would review them later.

The most compelling part of the course is the hands-on practice. It is conducted under safe conditions on a closed course, in a huge, empty parking lot, in cars with a low center of gravity; an instructor is always in the car. As shown in the video, we did the slalom — at first with an instructor driving; then each student took a turn driving. We learned how great the effect of small increases in speed can be on the ability to maneuver. We practiced emergency stops, then swerving while braking; we had the backing demonstration and the tailgating test, as shown in the video.

To learn how to anticipate potential hazards takes time, and experience. The InControl class can discuss this but not teach this. A driving simulator like the ones used to train airline pilots would help to build that experience under risk-free conditions. Video gaming technology is approaching the level that it could do this at a relatively low price. Computers are up to the task, but they would need multiple visual displays and a special “driver’s seat” controller. Lacking that technology, I have traveled many miles with my son, both as a driver and as a passenger, coaching him. His many more miles of experience stoking our tandem bicycle were a fine lead-in.

What did I learn in this class, with my nearly 50 years of experience as a licensed driver? Several things of importance — among them:

  • Despite my decades of experience, I answered several questions on the quiz incorrectly. I’m not going to provide a crib sheet– go take the course.
  • There is a very significant advantage to having different tires for summer and winter use, due not only to snow but also to temperature difference. Winter tires have “sipes” — small grooves –to develop a “snowball effect” — actually picking up snow so it will adhere to other snow, and improving traction. Tires should be replaced when tread is still twice the height of the wear bars.
  • Side-view mirrors should be adjusted wider than I had been accustomed to — so their field of view starts where the windshield mirror’s field of view ends.
  • The National Highway Transportation Safety Administration’s standards for a 5-star safety rating are lower for SUVs than for passenger cars, as a result of industry lobbying (Any surprise?)
  • Importantly, that antilock brakes do more than allow shorter stops. They allow steering during emergency braking, and we practiced this as shown in the video.
  • Most importantly, to me as a cycling instructor, that learning to manage risks is essentially the same for bicycling as for driving a car. The attitude is the same, and hazard recognition and avoidance are similar. One important difference is that a well-trained cyclist’s brain is the antilock braking controller on a bicycle.

As I write this today, my son has driven himself to his classes at the local community college 12 miles away. Like any parent, I cross my fingers every time he goes out the driveway, but I am pleased to report that he has is cautious and calm as a driver and that his driving inspires confidence, with exceptions at a very few times.

I wish he didn’t have to drive. I don’t like the environmental burden it imposes, and I don’t like the risk. If public transportation were at all reasonable, he would be using it. If the college were half as far away, he’d be riding his bicycle at least on days with good weather. For now, his getting a college education wins out over those concerns…

My September 11

My 10-year-old son Jacob’s school year hadn’t started yet on that brilliant clear September morning. My wife had left for work. I  had a business appointment in Belmont, a few miles from our home. Jacob and I set out for Belmont around 9 AM on our tandem bicycle. There wouldn’t be much traffic; the morning rush hour had passed. I had 30 years of safe cycling in Boston-area traffic, and little concern about our completing the trip safely.

Through an open car window I heard a word or two…Boeing 757 airliner…I got a spooky feeling. No radios were playing music or the boom chicka chicka booom chicka rant (expletive) rant rant rant which passes as music. I’d gladly have had that instead, thank you.

Jacob and I were turning left from where the car is in the picture. Note the hedge on the far left corner.

Jacob and I were turning left from where the white car is in the picture. Note the hedge on the far left corner.

Jacob and I were waiting just to the right of the double yellow line at a red light, to turn left from Waverley Street onto Thomas Street, near Belmont Center. Both streets are relatively narrow two-lane, two-way streets with light traffic. My left arm was extended in a very clear left turn signal. The traffic light turned green, and just as I began to swing the tandem to the left, I heard “beep beep” of a car horn behind us. A small gray sedan going about 30 mph passed us on the left side of the street, an insanely hazardous maneuver not only because of the possible collision with us, but also because someone might be making a right turn on red from Thomas Street, and would of course be looking the other way for traffic. A hedge blocked the view around the corner, too.

…two classic bicycle-on-wrong-side-of-the-street crash types, only with roles switched around…

Jacob and I rode the couple of hundred yards to the Belmont police station and spoke with Officer MacEachern, who was very supportive and professional. I didn’t get a look at the driver, but Jacob did, and identified her as a woman with brown or black hair (dyed?) and, he thought, wearing glasses. We reported the license number of the car, 350 JBA. The officer verified that it was for a gray Toyota Corolla sedan, and told us that it belonged to a 75 year old woman who lived in Belmont.

Officer MacEachern said that his department unfortunately could not issue a citation, since an officer had not seen the incident, but that he would go have a talk with the driver and that it might be possible to pull her license if she is incompetent.

I can understand being termporarily out of one’s mind. One time I was injured but felt no pain, even ignored the grating of bone on bone, just had to get — home. Once a truck strayed into my lane and sideswiped my car. Only my quick swerve avoided a head-on crash. I was going to turn around and chase after the truck except that my wife calmed me down.

Maybe the driver was the daughter of the car’s owner, who was in turmoil…maybe she had children at home and hoped to spend her final minutes with them.

Maybe she had someone on one of those planes — two flew from Boston — or in one of those buildings.

Jacob and I rode on to the home of my client where I shot the photo below.

Televison news coverage of the September 11 attack on the Pentagon.

Television news coverage of the September 11 attack on the Pentagon.

And that is how my son and I might have been killed on September 11 2001, not by Al Queda fanatics in red-hot hatred, though very likely through a ripple effect of their apocalyptic, ruinous madness onto someone I would probably have been happy to have as my next-door neighbor.

I went back a few weeks later and took the picture of the intersection, so I could include it in what is mercifully the story of a non-event and gets news coverage only here. Even if Jacob and I had been killed or gone to the hospital, our crash would have gotten even less attention than bicycle crashes usually do, on that day.

A take-away? Every  variety of opinion about Al Qaeda has probably already been expressed so I’ll only say this: adrenalin is a powerful mind-altering drug. It is available only by prescription except when you make it yourself, and because you do, police can’t cite you for it after a crash. But still, please think twice…

Barrier features

The same barrier can have more than one of the characteristics listed below, and they may be different for different types of vehicles.

  • Containment: The barrier prevents a vehicle from, for example, going over a cliff, or straying into oncoming traffic. Examples: curbs, guardrails, Jersey barriers.
  • Deflection: The barrier guides a vehicle that has gone off course back into the intended direction of travel. Examples: Jersey barriers, guardrails.
  • Threat: The barrier is hazardous in itself, so drivers shy away from it. Example: boulders, rigid bollards.
  • Sham: The barrier appears to pose a threat of damage to a vehicle but in fact is designed to minimize or avoid damage. Example: flex posts.
  • Stop: The barrier is intended to stop a vehicle approaching it.
  • Energy-absorbing: The barrier is designed to lengthen the time and so decrease the severity of an impact — same idea as with air bags or helmets. Examples. crash cushions, deformable barrier walls.
  • Warning: The barrier generates an audible or visual warning. Examples: rumble strips, proximity alarms.
  • Virtual: The barrier is established using signs, signals or markings and the laws which pertain to them.

A barrier may be benign for dual-track motor vehicles, yet  overturn single-track vehicles. These can topple over a low guardrail or Jersey barrier. A sham barrier for dual-track vehicles such as a flex post can tangle with the pedal or leg of a bicyclist, becoming a threat barrier. Reflectorized pavement markers, which are little more than a virtual barrier for dual-track vehicles, can throw a bicyclist –see this video example.

These considerations are lost in the design of many bicycle facilities. Barriers that are hazardous to bicyclists are being used because they are normal traffic-engineering practice, sometimes only due to lack of knowledge but sometimes enforced through design standards.

On the other hand, a high railing with a handlebar rub strip can serve as an effective and safe deflection barrier for bicyclists, even though it may be too weak to contain a heavier dual-track vehicle.

In Orlando, Florida recently, I saw two other examples of misuse of barriers:

  • Flex posts used ahead of and behind a parallel parking space which had been reconfigured as a bicycle parking station. Motorists parking in the next spaces would expect a light, stopping impact if they moved too far forward or back at very low speed. The colloquial expression is “kissing bumpers.”  Lacking this warning, a motorist already had backed up into the flex posts and damaged one of the bike racks. Here, rigid bollards or a guardrail would be appropriate.
  • Raised reflectorized pavement markers are being used on bike lane lines, neglecting the fact that bicyclists must enter and leave the bike lane, and often do best to ride along its edge. Nationally recognized guidelines specifically prohibit the use of raised markers here, for that reason.

The most common misused barrier for bicyclists is probably the low railing, which will topple a bicycle over. That is seen in many different varieties, ranging from the conventional Jersey barrier or guardrail to low wooden curbs lining boardwalks, to hand-height railings alongside paths.

When the marketing department plays traffic engineer

The photo shows “Cycle Lane” raised barriers, from the company Traffic Logix, on Long Island, New York, USA.

Traffic Logix Cycle Lane raised barrier

Traffic Logix Cycle Lane raised barrier

Here’s a quote from a page on the company’s Web site promoting  the barriers.

CycleLane is a smart, safe solution that provides a visual separation between vehicle and bicycle lanes. It ensures clear separation of traffic, with a unique sloped profile to prevent vehicles from entering the bike lane. The side adjacent to the vehicle lane has a high profile while the side parallel to the bike lane has a lower profile to divert bicyclists away from traffic and back into the bike lane.

Whoever wrote this evidently is not familiar with the physical concepts of center of mass or coefficient of friction. This device is a tripping hazard. A bicyclist who strays into it will not divert away from traffic, but instead will topple over into the next lane. There also is the possibility of a stopping-type incident with over-the-handlebars ejection when a bicyclist’s front wheel strikes the end of one of these barriers.

The barriers also are shown so tightly spaced that a bicyclist cannot merge into or out of the bike lane.

For these reasons, the US Manual on Uniform Traffic Control Devices, section 9C.02 says the following:

10 Posts or raised pavement markers should not be used to separate bicycle lanes from adjacent travel lanes.

Support:

11 Using raised devices creates a collision potential for bicyclists by placing fixed objects immediately adjacent to the travel path of the bicyclist. In addition, raised devices can prevent vehicles turning right from merging with the bicycle lane, which is the preferred method for making the right turn. Raised devices used to define a bicycle lane can also cause problems in cleaning and maintaining the bicycle lane.

The product is almost beyond belief; its design leaves the manufacturer wide open to liability lawsuits when bicyclists are injured or killed. The promotion could place frosting on that ugly cake, with claims of false advertising.

Still, this is only the most extreme example I’ve seen of ill-conceived, or at best, untested and unproven, marketing-driven purported safety measures targeted toward bicyclists. Some, like this one, are products, but others are design treatments which create the perception of safety without necessarily increasing actual safety.

Enough.

Dr. Furth’s and his students’ plan for South Brookline

On March 14, 2011, I attended a meeting in Brookline, Massachusetts, a suburb of Boston. At that meeting, Dr. Peter Furth of Northeastern University, and some of his students, gave a presentation on proposals for street reconstruction and bikeways in the southern part of Brookline.

Proposed treatment for West Roxbury Parkway

Proposed replacement of two two-lane one-way roadways with shoulders by a narrowed two-way roadway without shoulders and an adjacent multi-use path; Newton Street (up the embankment at the left) to provide local access only.

Most of the streets in the project area are fine for reasonably competent adult and teen cyclists to share with motorists, though one street, Hammond Street, is much less so, with its heavy traffic, four narrow lanes and no shoulders. I do agree with a premise of the presentation, that bicycling conditions could be improved, but I suggest different treatments, such as conversion from four lanes to three, with a center turn lane which becomes a median at crosswalks, also freeing up room at the sides of the roadway for motorists to overtake bicyclists.

Please read through this introduction before looking through the photo album I have posted with images from the meeting presentation, and drawings which were taped up in the meeting room.

My Concerns with the Proposal

Generally, I am concerned with the hazards and delays — and in winter, complete lack of service — which the proposal introduces for bicyclists, and with the blockages and longer trips it introduces for motorists, resulting in delay and in increased fuel use and air pollution. Some specifics:

  • The proposed system of narrow two-lane streets and segregation of bicyclists onto parallel paths makes no provision for the foreseeable increasing diversity of vehicle types and speeds as fuel prices rise. This trend can only be managed efficiently and flexibly with streets that are wide enough to allow overtaking.
  • Proposed paths are on the opposite side of the street from most trip generators, and many movements would require bicyclists to travel in crosswalks, imposing delay, inconvenience and risk for bicycle travel on the proposed route and on others which cross it. Small children would not safely be able to use the proposed routes unless accompanied by an adult, same as at present.
  • The proposal would further degrade or eliminate bicycle access in winter, because of the proposed 22-foot roadway width, and because the proposed parallel paths could not be kept ice-free even if they are plowed.
  • Though intersections are key to maintaining traffic flow, the proposal puts forward an incomplete design for most intersections and no design for some of them.
  • The narrowed streets provide no accommodation for a vehicle which must stop while preparing to turn left into a driveway, or to make a delivery, or to pick up or discharge passengers, for bicyclists who must travel in the street to reach a destination on the side opposite the path, or for bicyclists who wish to travel faster than the path allows.
  • The proposal includes no discussion of improvements to public transportation, which would be key to reductions in congestion and fossil fuel use. There are no bus turnouts, although Clyde and Lee Streets are on an MBTA bus line, school buses use the streets in the project area, and additional bus routes are foreseeable.
  • The proposal includes a 12-foot-wide service road along Clyde and Lee Street, part of which is to carry two-way motor traffic along with bicycle and pedestrian traffic. At times of heavy use, 12 feet on the Minuteman Bikeway in Boston’s northwestern suburbs is inadequate with only pedestrian and bicycle traffic. 12 feet is not wide enough to allow one motor vehicle to pass another. Larger service vehicles (moving vans, garbage trucks etc.) could access parts of this service road only by backing in, or by driving up a curb and across landscaped areas. These vehicles would completely block other motorized traffic on the service road.
  • The proposal is expensive because it requires tearing up every one of the streets in order to narrow it, not only construction of a parallel path.

Confusion in the Presentation

There also was confusion in the presentation:

  • North is confused with south, or east with west in the captions to several photos. Due to the confusion, some photos show a path on the opposite side of the street from where the plan drawings place it.
  • Some items in the illustrations are out of proportion. In one illustration (the one near the top in this post), a two-lane arterial street is only 10 feet wide, based on the height of a Segway rider on an adjacent path, or else the Segway rider is 12 feet tall, riding a giant Segway.
  • Other details are inconsistent, for example, showing a sidewalk in a plan drawing, but no sidewalk in an image illustrating the same location.
  • There is confusion about location of some of the photos. Some cross-section drawings are shown without identification of the location in the plans. The location of one cross section is misidentified.
  • The proposal makes unsupportable claims about safety.

There also is an ethical issue: in their presentation, the students have appropriated a number of Google Street View images without attribution — a violation of copyright and of academic ethics. (Furth’s students also plagiarized photos from my own Web site for a different presentation, but I digress.)

Overview and Conclusions

The proposal generally attempts to make bicycle travel a safe option for children and for people who are new to bicycling. It fails to accomplish that, due to problems with access across streets to the proposed pathways. It also adds complication and delay for motorists and for the majority of existing and foreseeable bicycle users. It degrades and sometimes eliminates bicycling as an option in the winter months, and it pays no attention whatever to public transportation.

I have no objection to construction of a path in the parkland adjacent to the streets in the project area, but the proposal also works to enforce the use of the path by reducing the utility of the road network for bicyclists as well as for other users.

I do think that street improvements are desirable, and on one street (Hammond Street) a high priority to improve bicycling conditions, but these improvements can be achieved mostly through restriping, without the massive reconstruction, or rather, deconstruction, that has been proposed.  This narrowing the roadways is intended to increase greenspace, and also  apparently to reduce speeding, but the proposal goes way overboard in reducing capacity, convenience and flexibility. There are other options to reduce speeding, most notably enforcement and traffic-calming measures which affect speed without decreasing capacity.

The large multi-way rotary intersection of  Hammond, Lagrange and Newton Streets, West Roxbury Parkway and Hammond Pond Parkway is the one place where I consider reconstruction to be a high priority.

Education also is an essential element of any attempt to make bicycling safer and a more practical option.

Larger Contextual Issues

Long-run issues of energy cost and availability raise questions about the viability of sprawled suburbs whose residents are dependent on private motor-vehicle travel.

South Brookline is more fortunate. It is a medium-density residential area of single-family homes, only about 5 miles from the Boston city center and also only a few miles from the Route 128 corridor, a major employment concentrator. Schools, places of worship, parklands and shopping are closer than that. Bicycling can and should have a role here, but for many people and many trips, it is not an option, due to age, infirmity, distance, and the need to transport passengers and goods.

South Brookline could benefit from a comprehensive transportation plan, including strengthening of public-transportation options and maintaining arterial roads with capacity for varied existing,  foreseeable and unforeseen uses.

Developing such a plan requires skills, resources and time beyond what I can muster, and so I’ll not attempt that here.

Now, please move onto the photo album.

Traffic theory: improving traffic signals to reduce pointless delay

A real-world time-space diagram, from Wikimedia commons.

A real-world time-space diagram

In theory, there’s no difference between theory and practice, but it practice, there is.

attributed to:
Yogi Berra
Jan L. A. van de Snepscheut
Albert Einstein

An optimal traffic-signal system would never present anyone with a red light or a don’t walk signal unless there actually is interfering traffic. In theory.

In practice, though, it may be desirable to introduce some delay in order to smooth the flow of traffic — to get vehicles on board a “green wave.” Traffic engineers think in sophisticated ways about this issue, but do not have the real-world tools to resolve it. While synchronized traffic-signal systems and sensor-actuated signals already improve the situation over uncoordinated timed signals, better sensing and more sophisticated software could, at least in theory, achieve much more.

Probably the most difficult part of the problem is in sensing approaching vehicles and pedestrians far enough ahead of an intersection so signals will change as they reach the intersection. Sensors are expensive, and many more would be needed. On the other hand, in a city dotted with security cameras, the sensor data may be easier to obtain, especially if traffic control is a goal when installing the equipment.

I am emphatically not describing so-called intelligent highway systems, intended to automate driving by taking control of vehicles. The driver then supposedly becomes a passenger, free to dial the cell phone, read the newspaper, watch TV or apply makeup without concern. For automated control to work, the system must exert at least as reliable control over vehicles as attentive drivers do. More yet: car makers have huge legal problems resulting from defects that injure only a small number of customers.

Automated control presently is applied only under very restricted conditions, on airport shuttle trains and the like. Even with a great increase in sophistication, it’s hard to conceive of how automated control (other than in collision-avoidance systems) would work on any roads except limited-access highways restricted to vehicles equipped for it.

Even under these conditions, there are difficult technical problems. Collision-avoidance systems to prevent collision with large objects ahead are just beginning to be common. Avoiding debris in the road, potholes and other smaller obstacles requires sophisticated sensing which a driver routinely performs — but well beyond the abilities of automated systems.

So, I am describing not a system to take over control of vehicles, but one to improve control of traffic signals. Humans would retain the ability to prevent collisions, and malfunctioning of the system would lead only to delay, not to crashes. The system would make little difference to anyone — motorist, bicyclist or pedestrian — except to reduce pointless delay.

Will this happen? If so, when and where? One promising thought is that it can happen bit by bit, at one intersection and another, rather than all at once along an entire highway.

Alleycat racers

A British cyclist who goes by the online name gaz545 on YouTube has posted a version of one of Lucas Brunelle’s “alleycat race” videos, with voice-over commentary. Bravo gaz545!

Lucas Brunelle is, or was, a bicycle courier, but he distinguishes himself by shooting videos of the alleycat races — anything-goes races through cities, in urban traffic. The racers are mostly from the bicycle courier community. A Brunelle video is now making the rounds of 40 cities in a bicycle film festival.

Brunelle’s colleague Kevin Porter, who appears in some of his videos, served with me on the massbiek Board for a ocuple of years, something of an attempt to draw the courier community into mainstream advocacy.

Allow me to describe the fundamental difference between alleycat racing and responsible, sane cycling (or responsible, sane driving a car, for that matter — it’s the same idea).

The rules of the road establish who may go and who must yield right of way, so road users know what to expect of each other — but also, beyond that, in every situation where it is possible, both the road user who may go and the one who must yield are in full view of each other and able to avoid a collision if the other makes a mistake. Where sight lines are obstructed, traffic signs and signals direct road users to slow or stop, and allow them to take turns where flows of traffic cross.

Alleycat racers flout all this. They rely on their wits, and on guessing what other road users will do. They ride as if they were invisible. Much of the time, they are invisible, hidden behind sight obstructions where they can only guess what is around the corner. They ride opposite the direction of traffic, between lanes, where one driver’s slight change of direction will result in a head-on collision. They ride in extremely close quarters with vehicles which, if the driver doesn’t do as the alleycat has guessed, will sideswipe them, collide with them or run them over.

Alleycat racing is an extreme sport: a sport that involves a serious risk of severe injury or death — but more than that. Most so-called extreme sports, for example motorcycle jumping, involve only self-imposed risks. Participants in extreme fighting sports impose serious risks on their opponents, but by consent. Alleycat racers, on the other hand, impose serious risks on other people without obtaining consent and without warning. There’s an expression to describe this: breaking the social contract.

Brunelle’s videos are of high technical quality. Also, I’ll admit to some admiration for the skill of the alleycat racers. It is a level and type of skill normally required of a soldier in combat, a police officer confronted with an armed and violent offender, a cyclist or motorist facing an imminent threat of a collision. Skill is good. Any cyclist, any driver will face emergency situations occasionally. I’d think that perhaps the most skillful cyclist imaginable would be a reformed alleycat racer, if such a character exists.

Tamer motorists and cyclists can learn anticipation of hazards, braking, swerving — through training, and practice in the controlled environment of the skid pad or empty parking lot. My Bicycling Street Smarts turorial is one of a number of resources that teach these skills. But to put these skills intentionally to the test in the public streets is to court unnecessary risks, and to put other people at risk as well. The crash types and crash rate described in the Dennerlein-Meeker study of Boston bicycle couriers reveal the risks that couriers take — and the couriers aren’t even riding at nearly the extreme level seen in alleycat races.

Gaz545 doesn’t know of any injury that occurred during the London alleycat race, though I saw a number of very close calls in his video. However, in an alleycat race in Philadelphia which passed through the campus of the University of Pennsylvania, a participant came racing down off an overpass on a campus walkway — going from right to left here –


View Larger Map

(The break in the image of the overpass is due to the boundary between photos used in the satellite view)

The alleycat racer collided with a pedestrian — a student’s mother who was visiting the campus — knocked her down, injuring her seriously, and raced off. Other racers witnessed the incident. Police interrogated several but were unable to obtain identification of the hit-and-run racer from any of them.

Let’s describe the alleycat racers for what they are: outlaws who pump each other up to ever more extreme conduct in traffic, endangering others, not only themselves, and then when that danger results in injury to an innocent bystander, they adhere to a code of silence.

The pedestrian in the Philadelphia incident filed a lawsuit against the University for allowing the race to take place on its property, though the University had no idea that there would be a race. Suing the University was the only way that she could hope for any recourse.

It isn’t too far-fetched also to ask whether police might infiltrate the alleycat community to find out where a race is scheduled and perform an effective sweep-up. Alleycat racers are not “silly cyclists” (gaz545′s term, describing the cyclists in his other videos) making dumb mistakes in traffic because they don’t know any better. Alleycat racers act in wanton disregard for public safety. They do serious damage to the reputation of other cyclists as well, and I have very little sympathy for them.

(And here’s a link to Lucas Brunelle’s Web site, now that you have read what I have to say about it. There is no mention on it of the Philadelphia race, for whatever reason.)