Author Archives: jsallen

Some thoughts about self-driving cars

Google’s report on its self-driving cars:

Most than half of the collisions reported in this document are slow-speed rear-enders of the Google cars. That’s unusual. It might be that the behavior of the Google cars is more cautious than what human drivers expect, so the Google cars stop more often abruptly or at unusual places, and so are not tailgater-friendly. I’d suggest that the Google cars might be equipped with a rear-facing warning device.

It seems to me that self-driving cars will be able to avoid any collision where a human driver could avoid fault, and others. In other words, operators of non-automated vehicles (including bicycles) and pedestrians who follow the conventional rules of the road will be able to operate safely around automated vehicles. Vehicles with automated crash avoidance (not necessarily completely automated vehicles, even) will not rear-end bicycles, and so the premise of fear from the rear evaporates if automated crash avoidance becomes universal with motor vehicles. Self-driving cars will not be able to avoid collisions where avoidance would require violating the laws of physics. Automated vehicles will be able to avoid some collisions which place the potential colliding vehicle or pedestrians outside the field of view of a human driver, such as right hooks, as long as there is a clear sight line to the automated vehicle’s sensor. Same for a large truck’s high hood which prevents the driver from seeing a pedestrian crossing in front. Automated vehicles will not be able to avoid left-cross collisions where the bicyclist or motorist is passing on the right of other vheilces and concealed by them, or pedestrian dart-out collisions.

The concept of fully networked vehicles is supposed to address this problem. All vehicles approaching the same place in the road network are envisioned as communicating with each other even when they are hidden from each other’s view. Speaking as someone with an electrical engineering degree, I consider this at best a very difficult proposition, and it might be described as a pipe dream. Bandwidth, interference and reliability issues lead me to ask “what could possibly go wrong?” Also, instrumenting every object on the road is only practical on a limited-access highway — no, not even there, because there will still be broken-down vehicles, wild animals, debris. On other roads, is every pedestrian going to carry a transponder? I don’t think so.

One important concern is that automated crash avoidance is easily hacked by rolling a trash can out into the roadway, and the like. The caution which automated crash avoidance inherently incorporates changes the dynamic from that between humans: no game of bluff. To me, this means that automated vehicles will be extra-cautious in the presence of other drivers and pedestrians who do play the game of bluff, and so the progress of automated vehicles will be slow and erratic in, for example, Boston traffic.

All this leads to the question: does behavior change as these vehicles become more common? Does infrastructure change? Every new technology takes a while to find its feet. As Marshall McLuhan said, “We look at the present through a rear-view mirror. We march backwards into the future.” Better or worse for bicyclists and pedestrians? And why? We have some control over this depending on the direction which is set for the technnology, but also, time will tell.

Another serious issue I’ve heard mentioned is the car which is not only driverless but passengerless. There is potential for an increase in traffic if a car can be called to meet a person (like a passengerless taxi), or directed to drive around and around the block empty when a parking space can’t be found. I don’t have the analysis to say how serious this problem will be. It could also go the other way, with fewer cars on the road needed, because the car-sharing model works better when a car can be called rather than only stationed. Again, time will tell.

Ogden, Utah skateboarder stop

There’s plenty of confusion to go around here.

Deputy: “I don’t care, you’re right in the middle of the road.” No, the boarder was on the shoulder, at least in the part of the video the TV station broadcast.

Was that legal? Bicycling is allowed on shoulders in many states. I couldn’t find anything on that on the Utah legislative site section on bicycles,

But the man was on a skateboard, not a bicycle. Under Utah law, the skateboard is defined as a vehicle, last definition here: and so, under the law, the skateboarder should have been in the travel lane, not on the shoulder or a sidewalk, if any, as little sense as that may make.

So, the officer’s charge was false. If the boarder were defined as a pedestrian, then shoulder use in the absence of a sidewalk would be legal if the boarder was traveling opposite the direction of traffic (he wasn’t), — not that this is sensible when it would have required crossing to the far side of a multi-lane road.…/Title41/Chapter6A/41-6a-S1009.html.

There is a sidewalk, as shown in Google Earth and Street View images.

The TV station video is edited at 00:25. It doesn’t show the entire conversation between the deputy and the boarder before the boarder attempted to flee — so we don’t know about an opportunity to comply. Other question is how the boarder could comply if there was nowhere to go except up and down a road bordered by vegetation. The deputy ran after the boarder and attempted to stop him. Probably better to let him go. The boarder fought the deputy, violently. Not smart at all.

Change lanes in a roundabout?

Ohio cyclist Patricia Kovacs posted an e-mail asking some questions about roundabouts:

Ohio engineers are telling us to use the inner lane for left turns and U turns. Both the FHWA [Federal Highway Administration] and videos available on our local MPO [metropolitan planning organization] website say this. I shared this when we asked for updates to Ohio Street Smarts. If the FHWA and MORPC [Mid-Ohio Regional Planning Commission] are wrong, then we need to fix it.

Would you review the 8 minute video on the MORPC website and let me know what I should do? If it’s wrong, I need to ask them to update it. This video was made in Washington and Ohio reused it.

Looking further into the problem, I see a related practical issue with two-lane roundabouts, that the distance between an entrance and the next exit may be inadequate for a lane change. The larger the roundabout, the longer the distance in which to change lanes, but also the higher the speed which vehicles can maintain and so, the longer distance required. I’m not sure how this all works out as a practical matter. Certainly, turning right from the left-hand lane when through traffic is permitted in the right-hand lane is incorrect under the UVC [Uniform Vehicle Code], and results in an obvious conflict and collision potential, but I can also envision a conflict where a driver entering the roundabout does not expect a driver approaching in the inside lane of the roundabout to be merging into the outside lane.

All in all, the safety record of roundabouts is reported as good (though not as good for bicyclists and pedestrians), but I’m wondering to what extent the issues have been subjected to analysis and research. When I look online, I see a lot of roundabout *promotion* as opposed to roundabout *study*. Perhaps we might take off our UVC hats, put on our NCUTCD [National Committee on Uniform Traffic-Control devices] hats, and propose research?

Thanks, Patricia.

This post was getting long, so I’ve placed detailed comments on the Ohio video, and embedded the video, in another post. I’m also working on an additional post giving more examples, and I’ll announce it here when it is ready.

Here are some stills from the video showing the conflict between through traffic in the outer lane and exiting traffic in the inner lane.

First, the path for through traffic:

Path for through traffic in a roundabout

Path for through traffic in a roundabout

Next, the path for left-turning traffic:

Path for left-turning traffic in a roundabout

Path for left-turning traffic in a roundabout

Now, let’s give that picture a half-turn so the left-turning traffic is entering from the top and exiting from the right:

traffic in a roundabout, image rotated 180 degrees

Path for left-turning traffic in a roundabout, image rotated 180 degrees

And combining the two images, here is what we get:

Conflict between through traffic and exiting left-turn traffic

Conflict between through traffic and exiting left-turn traffic

The image below is from the Manual on Uniform Traffic Control Devices, and shows similar but not identical lane use. The arrows in the entry roadways direct through traffic to use either lane.

FHWA diagram of a roundabout with lane-use arrows.

FHWA diagram of a roundabout with lane-use arrows.

Drivers are supposed to use their turn signals to indicate that they are to exit from the inner lane — but drivers often forget to use their signals. Safe practice for a driver entering a roundabout, then, is to wait until no traffic is approaching in either lane, even if only entering the outer lane.

A fundamental conceptual issue here is whether the roundabout is to be regarded as a single intersection, or as a series of T intersections wrapped into a circle. To my way of thinking, any circular intersection functions as a series of T intersections, though it functions as a single intersection in relation to the streets which connect to it. Changing lanes inside an intersection is generally prohibited under the traffic law, and so, if a roundabout is regarded as a single intersection, we get the conflicts I’ve described.

Sometimes, dashed lines are used to indicate paths in an intersection, when vehicles coming from a different direction may cross the dashed lines after yielding right of way or on a different signal phase. More commonly, a dashed line  indicates that a driver may change lanes starting from either side. The dashed lines in a two-lane roundabout look as though they serve the second of these purposes, though they in fact serve the first. These are shorter dashed lines than generally are used to indicate that lane changes are legal, but most drivers don’t understand the difference.

That leads to confusion. If you think of the roundabout as a single intersection, changing from the inside to the outside lane is illegal anywhere. If you think of the roundabout as a series of T intersections, changing lanes should occur between the entries and exits, not opposite them –though there is also the problem which Patricia mentioned, that a small two-lane roundabout may not have much length between an entry roadway and the next exit roadway to allow for a lane change. That is, however, much less of a problem for bicyclists than for operators of wider and longer vehicles. It would be hard to construct a two-lane roundabout small enough to prevent bicyclists from changing lanes.

My practice when cycling in conventional two-lane traffic circles — and there are many in the Boston, Massachusetts area where I live — is to

  • enter from the lane which best leads to my position on the circular roadway — either the right or left lane of a two-lane entry;
  • stay in the outer lane if leaving at the first exit;
  • control the inner lane if continuing past the first exit;
  • change back to the left tire track in the outer lane to prepare to exit.

That way, I avoid conflict with entering and exiting traffic in the outer lane, and I am making my lane change to the right in the slow traffic of the circular roadway rather than on the straightaway following it. This is what I have found to make my interactions with motorists work most smoothly. Why should a bicyclist’s conduct in a roundabout be different?

It is usual to be able to turn right into the rightmost lane of a multi-lane rodway while raffic is approaching in the next lane. I don’t know of any other examples in road design or traffic law in the USA where a motor vehicle is supposed to turn right across the lane where another motor vehicle is entering it. Bike lanes are sometimes brought up to intersections, though the laws of every state except Oregon require motorists to merge into the bike lane before turning. The illustration below, from Dan Gutierrez, depicts the problem.

Right hook conflicts, from Dan Gutierrez's Understanding Bicycle Transportation

Right hook conflicts, from Dan Gutierrez’s Understanding Bicycle Transportation video and course.

Applicable sections or the Uniform Vehicle Code are:

  • 11:304 (b) — passing on the right is permitted only when the movement can be made in safety.
  • 11:308 (c) — a vehicle shall be driven only to the right of a rotary traffic island.
  • 11:309 (a) — no changing lanes unless it can be done in safety
  • 11:309 (d) — official traffic control devices may prohibit lane changes
  • 11:601 (a) Right turns – Both the approach for a right turn and a right turn shall be made as close as practicable to the right-hand curb or edge of the roadway.


Comments on the Ohio roundabout video

I’ve moved the comments here from another post, which was getting long.

Here’s the Ohio video:

Summarizing my comments about the video, it shows roundabouts, a useful, time-efficient though space-intensive intersection design, but it gives some questionable advice on design and on how to use roundabouts. There are safety issues, and also legal implications are unclear, due to a contradiction of normal rules of the road.

  • While good advice for pedestrians is given, the video includes an overhead view of a roundabout in a residential area with a crosswalk at only one of the three legs of the intersection.
  • The advice for bicyclists to walk in the crosswalks is a surrogate for good design of crosswalks (or crossbikes) so bicyclists can safely ride through them, also reducing delay to both bicyclists and to traffic on the roadway.
  • In the video, a bicyclist is shown properly centered in the right lane to exit a roundabout, but just before that he is riding adjacent to a truck, contrary to advice also given in the video. He was in danger of being left-hooked at the previous exit.
  • Contrary to normal rules of the road, the video shows and advises that some drivers exit the roundabout from the inner lane, while other vehicles travel through in the right lane. Through-traveling drivers are expected to yield to the ones left-hooking them. What traffic law actually applies is unclear. If there is a special rule for roundabouts, it violates the usual rule and also violates the principle of destination positioning. Bicyclists usually would rather be in the right lane when exiting,

More-detailed comments about the video are below. The URL at the start of each comment links to the location in the video which relates to the comment. I’ve published the same comments on the YouTube page with the video.

0:50 Overhead view shown briefly shows the inner lane leading to a 4-lane exit. However, if you look closely, there are nonetheless dashed lines between the lanes and through arrows in the outer lane, — so the markings do not indicate that all traffic coming from previous entrances must use the inside lane. The markings maximize capacity by allowing exiting from either lane, regardless of where entering — though there is then a conflict between traffic passing an exit in the right lane and exiting from the left lane. My best advice for bicyclists who are riding through the roundabout is to ride centered in the outer lane while approaching the exit to avoid an unnecessary merge and avoid being right-hooked by exiting traffic or left-hooking through traffic, while also being in clearer view of entering traffic than if riding around the outside. Also, the drawing does not address all bicycling and walking movements. There is one cyclist shown in the illustration, riding with the direction of traffic on the sidewalk directly above the roundabout in the image, and that’s OK, but there are no ramps to and from the roadway to the sidewalk; on the other side of the intersection, there is no sidewalk; and there are no crosswalks across two of the three legs of the intersection, in a residential area.

1:00 Police officer narrating indicates that roundabouts “make our communities safer not only for motorists, but for pedestrians as well.” This contradicts the example in the overhead view, which lacks a full complement of sidewalks and crosswalks, and he also does not mention bicyclists.

2:00 Yield principle is good. Yielding is a fundamental principle of traffic operation which is not widely-enough understood. 2:10 vehicles are shown exiting the roundabout in the right-hand lane of a four-lane roadway, and that’s OK.

2:50 “The lane allows left turn, straight-ahead movements and U turns only,” with the unstated implication that drivers must remain in the left lane while exiting.

2:55 “Allowable right-lane movements include right turns or straight-ahead movements.” The two previous statements together establish a left-hook conflict between straight-ahead movements in the right lane and right turns from the left lane.

3:12 Animation at shows a vehicle exiting from the left lane, crossing the right lane in which through movements are permitted.

3:34 “When driving in the left lane, always maintain your lane position until you exit” — left-hook conflict.

3:40 A vehicle making a straight-ahead movement yields to traffic in both lanes when entering. The entering driver may not know whether the driver coming from the left intends to exit (conflict!) or not (no conflict!). The exiting driver is turning right from the left lane, in violation of the principle of destination positioning.

4:15 “The driver in the right lane cuts off the driver in the left lane intending to exit.” This is exactly the same as saying “The driver in the right lane traveling straight through cuts of the driver in the left lane intending to turn right.” The vehicle in the left lane is behind the one in the right lane and not in a position where the leading driver would normally have to look when continuing on a roadway. Both the movements shown — going straight through in the right lane and turning right from the left lane — are permitted movements, according to the animation shown previously — but turning right across a travel lane without yielding is a violation everywhere except, as describe here, in a roundabout.

4:30 “Never change lanes inside the roundabout.” Troubling advice, and especially for bicyclists — not only results in hook conflicts, but also results in unnecessary delay.

4:45 “U Turns are only allowed in the left lane” – Good enough except for the issue with hook conflicts at the exit.

5:15 “If you follow a truck into a roundabout, do not attempt to pass.” Good advice anywhere it would be necessary to share a lane with a large truck to pass it.

5:26 “When emergency vehicles approach, always give them the right of way.” More generic good advice.

6:03 “Never stop inside the roundabout. Instead, continue through the roundabout, then pull over to the shoulder…” (when an emergency vehicle needs to use the roundabout). This would apply in any intersection, but it may be a bit more confusing in a roundabout.

6:10 Advice for pedestrians is good, assuming of course that there is a crosswalk. “A roundabout crosswalk is the same as an unsignalized crosswalk”.” Well, it is an unsignalized crosswalk. More generic good advice.

6:40 “Bicyclists are encouraged to use the crosswalks by walking their bikes.” Sure, bicyclists may become pedestrians and walk their bikes but this is contrary to the current Dutch practice where the bikeway is designed so motorists can yield to bicyclists who are riding, see A person walking a bicycle in a crosswalk is delayed, and delays other traffic, more than one who is riding, and, broadside to the traffic lanes, is a much wider obstacle — and so more vulnerable — than a pedestrian without a bicycle. Don’t expect bicyclists to obey “Mickey Mouse” advice, but do expect them to get into trouble when crosswalks aren’t designed for safe yielding at bicycle speeds. Safe practice in a crosswalk which is not designed to work at bicycle speeds is to slow or stop before entering the crosswalk, allowing drivers to yield, and then cross quickly, but not all bicyclists may recognize the need to slow, and brakes also occasionally fail. Safest practice is to design crossings so everyone can see clearly and yield, regardless of who is required by law to yield. A roundabout should have ramps to/from the sidewalk, aligned with the direction of travel on the roadway, so bicyclists may enter from the roadway and exit to the roadway…see page 168 of FHWA document here: A Wisconsin page giving roundabout resources includes a link to a video describing both options for bicyclists (near the end of the video).

6:50 “If you choose to ride through the roundabout, the same rules apply for a bike as for an automobile.” The bicyclist is hidden behind a truck while crossing a leg of the intersection and then exits at the next leg, properly centered in the outer lane. The bicyclist would have been vulnerable to a right hook if the truck had turned right at the first exit, and would have been safer merging to the inside lane, and then back to the outer lane — or even better, not riding next to the truck, as was previously suggested in the video. The video image does not show a conflict with a bicyclist exiting from the inside lane, though this problem is shown (and bad advice is given) earlier in the video for motorists. Also, if a roundabout is designed for a 20 mph speed, riding through it is not nearly as intimidating as the video would make out — and a bicyclist in the roundabout is not going to cause nearly as much delay, if any, as one in a crosswalk or bikeway outside the roundabout– granted that riding in the roundabout is only for confident bicyclists.

7:54, again: “Never pass or drive adjacent to a truck in a roundabout.” This is exactly what the bicyclist was shown doing.

Translation of complete paper on German bikeways 1897-1940

I’ve prepared a full translation of the important paper by Dr. Volker Briese of the University of Paderborn in Germany about the history of German bikeways from 1897 through the start of World War II. This has previously been available only in German, or in a highly condensed version in English in the narrowly distributed Proceedings of the 1993 International Cycle History Conference. You may read the English translation here, and also find your way to the other versions as well if they are what you would prefer.

ShelBroCo Magic Green Paint

Here’s a high-tech product which deserves to be used in every new bicycle infrastructure project. The linked page gives a thorough description and videos!


An example from one of the videos

An example from one of the videos

Volvo promotes a reflective paint which fades in 10 days!

The last word in safe bicycling, NOT! I mean, this could be a premature April fool’s joke!

The Volvo promotion, also touted on the blog The Verge, is more an exercise in creative photography than anything else, but also does a lot of fearmongering. Buses are shown twice endangering bicyclists to the extent I have to wonder whether the videos were posed. Another video shows a bicyclist smashing into the back of a car, which can be avoided by maintaining safe following distance, not by any lights or reflectorized items. A bicyclist describes a left-hook (in the UK, right-hook in right-side driving countries), a type of crash which is avoided by not overtaking between a vehicle and the kerb (curb).

It is very easy to make reflectorized materials look splendidly bright by using a lamp on or next to the camera. As usual in promotions of nonstandard reflectorized products, a bicycle is shown in the video emblazoned with the product — which only works for the driver of a motor vehicle whose headlamps are aimed at it — but without the headlamp required by law for the bicyclist to alert others. The bicycle’s saddle is at an impossibly uncomfortable angle, and who is to imagine that the chain, tires — and rims — on a bicycle with rim brakes — would be spray-painted? A photo of three bicyclists is clearly doctored: there is no way that one after the other would light up. Same with another where the bicyclist’s clothing flashes on and off while the bicycle remains bright. In any case, reflective coatings are nothing new, but one which is designed to last only 10 days, now that is a new twist in safety products. For information about earlier reflective coating promotions:

Another pretty picture from Indianapolis

Here’s another picture from Indianapolis which I discovered online. Its geometry is slightly distorted, as it is from a screen shot. New York Street, in this picture, makes a two-way pair with Michigan Street, which I discussed in my previous post.

You may click on the images to enlarge them and get a clearer look.

New York Street at Arsenal -- proposed treatment

New York Street at Arsenal — proposed treatment

Let’s compare this with the Google Street View on which it is based:

New York at Arsenal Street -- Google Street View

New York at Arsenal N.Arsenal Avenue — Google Street View

I’m not going to discuss this in such detail as in my previous post, but please note:

  • The proposed two-way separated bikeway is no more than 5 feet wide where the two bicyclists are traveling.  (Compare with the bicyclists’ height and the diameter of their wheels, approximately 27 inches.) This bikeway is also between raised curbs and doesn’t even begin to be wide enough for safe two-way travel. It isn’t even wide enough to conform to guidelines for one-way travel.
  • The perspective is odd. The bikeway becomes wider and the travel lanes, already barely wide enough to contain the small cars shown, become narrower in the background.
  • The bikeway is described as “protected” but it crosses several driveways and, astonishingly, it opens into the street in the foreground with bicyclists facing the direction of traffic. What are bicyclists supposed to do here? Riding against traffic is illegal, aside from being highly hazardous. Here’s the view from across the intersection with Arsenal Avenue.
New York Street before Arsenal Street

New York Street before N. Arsenal Avenue

  • Some additional trees have been added in the proposal; smooth pavement has replaced the worn pavement in the Street View,  the cloudy sky has been replaced by a blue sky, and shadows have been added to simulate a sunny day. As in the picture in the earlier post, these changes create an optimistic, appealing effect, but they have nothing to do with the bikeway.
  • And, again, as I asked in the other post, how is this bikeway to be cleared of snow?

New York Street is much narrower than Michigan Street until a couple of blocks east of this point. I don’t see how there could be room for  both a contraflow bike lane and a with-flow bike lane. In my opinion, two-way bicycle traffic is better accommodated on Michigan Street. A route could bypass the narrow section of New York Street by using Vermont Street, a couple of blocks to the north.  That street also has an underpass under Interstate 70 — see Google map. This route would, however, require two-way bicycle traffic on reversing the one-way direction of part of N. Arsenal Avenue.

New York Street connections

New York Street connections

Any bike lane on the narrow section of New York Street ought to be on the left side, on the opposite side from parking: looking up and down the street in Google Street View will show that the present bike lane is in the door zone of parked cars.

Treatments at intersections should favor motorists’ merging into the bike lane before turning, and bicyclists’ overtaking turning motorists on the street side.

PeopleforBikes approves transformation of Michigan Street, Indianapolis with Photoshop

[Note: I’ve changed the title and a few words in this article, because a reader has pointed out the the drawings I’ve commented on, while approved by PeopleforBikes, are not from PeopleforBikes — the impression which an article I cited gave. Nobody has explained as of yet who did the drawings.]

This article critiques a proposed treatment for Michigan Street in Indianapolis, Indiana. Indianapolis is one of four cities which have been targeted for grants by the advocacy organization PeopleforBikes — whose financial support and agenda, let it be clear, and despite its name, are from the bicycle industry.

It’s only fair for me to criticize if I can suggest a better alternative. But first let’s look at existing conditions on Michigan Street

Michigan Street approaching Keystone Street in front of the Thomas Gregg Elementary School is shown in the Google Street View below, from July, 2011.

Michigan at Keystone, Octobrer 2011

Michigan at Keystone, October 2011

Michigan Street presently has a bike lane, visible behind the car in the Street View image. (The car is straddling the bike lane, having given the Google camera car a wide clearance when passing on the right.) The door zone placement of the bike lane creates hazards which reinforce the impression among uninformed people that the government has done the best it could, short of constructing a sidewalk-type bikeway. There are cars parked adjacent to the bike lane in the next block.

Other Street Views show a small number of cars parked on both sides up and down the street. An earlier Street View, from July 2009, shows how the leftmost lane was narrowed and the other lanes were shifted over to make room for the bike lane on the right. You can see the lane lines which were blacked out.

Michigan at Keystone in 2009

Michigan at Keystone in 2009

The left lane was already used for parking before it was narrowed, but now its narrowness, along with the parking, makes it hardly useable for travel.

Taking a larger look at the neighborhood (see Google map) —

Google Map of East Indianapolis

Google Map of East Indianapolis

Michigan Street is half of a one-way pair, with New York Street, a block to the south. These are arterial routes in and out of the city center, which is to the west. Traffic is very light  in Street View images, but it must be heavier during the morning and evening rush hours. The long north-south blocks make wrong-way local bicycle travel on these one-way streets tempting. There is a bike lane on the right, intended for one-way travel.

What, in my opinion, is the best which could be done here to provide for local bicycle travel in both directions?

Let me suggest that making the leftmost lane of each of these streets into a contraflow bikeway would provide for two-way bicycle traffic, with the low stress which would be attractive to novice and casual bicyclists, while maintaining a normal and expected pattern of traffic movements: the streets would be one-way for motorists and two-way for bicyclists.

This would remove parking on one side of the street, but is parking an issue here? Because the blocks are  long from north to south but short from east to west, there are many more available parking spaces on the north-south streets than on Michigan Street and New York Street. The small number of parked vehicles on Michigan Street in the Google Street views suggests that removal of parking on one side of the street would not result in parking overflow. Even for deliveries, the blocks are so short that parking around the corner on a north-south street would not be a much of a hardship.

There is still a concern with this idea, that some bicyclists would ride opposite the flow of traffic in the contraflow bike lane. That issue can be addressed by also having a with-flow bike lane on the left side. Then bicycle traffic adjacent to the motor traffic is traveling in the same direction, and the opposite-direction bicycle traffic is closer to the curb, conforming to the normal traffic pattern and expectations. Here’s an example of this type of treatment, from Fresh Pond Park in Cambridge, Massachusetts:

Two-way bikeway on left side of one-way street

This is a treatment approved for the Manual of Uniform Traffic Control Devices, the national standard reference. In the standards-setting document describing contraflow bicycle lanes, note the wording:

Where used, a contraflow bicycle lane should be marked such that bicyclists in the contraflow lane travel on their right-hand side of the road in accordance with normal rules of the road, with opposing traffic on the left…

A bicycle lane for travel in the same direction as the general purpose lanes may be placed on the left hand side of the general purpose lanes.

Appropriate use of short median strips before intersections could direct motorists to merge into the with-flow bike lane before turning left, but prevent them from merging into the contraflow bike lane, and with minimal impediment to plowing..

There is adequate width on both Michigan Street and New York Street to install this treatment, while still having two through travel lanes, as well as parking and bus stops on the  side without bicycle lanes.

I’m not saying that this treatment is ideal. There are still issues with motorists turning across the bikeway and entering form side streets. However, the normal and expected pattern is maintained, with traffic keeping to the right. The one-way street becomes a two-way street, except that only bicycle traffic may travel in one of the two directions.

It might be desirable to reverse the one-way pattern if more trip endpoints and connecting routes are on the side of the street which would be opposite the bicycle lanes, and to place the morning rush-hour traffic on New York Street to get it away from the elementary school.

Now let’s see what PeopleforBikes is promoting.

Photoshop drawing of proposed Indianaplis bikeway

Photoshop drawing of proposed Indianapolis bikeway

The article which includes the Photoshopped illustration above makes the following statement:

Leaders with the national organization People for Bikes said protected bike lanes are like “sidewalks for bikes” and Indianapolis needs more of them.

It’s hard enough to overcome people’s false sense of security about bicycling on sidewalks without having to fight the bicycle industry’s Astroturf advocacy organization!

The statement, and the soothing but inaccurate term “protected bike lane”, take advantage of the incorrect and often fatal misconception by casual cyclists and parents that sidewalks are safe places for bicycling. Decades of research show that bicycling on sidewalks produces a crash rate higher than on streets, and also show that barrier-separated on-street bikeways are appropriate, preferable and reasonably safe only under a limited range of conditions and with the application of strict design standards which make them very different from sidewalks. In spite of all this, barrier-separated on-street bikeways are by and large the only thing which PeopleforBikes promotes. And here, it’s promoting them by ringing the bell of the public’s fondness for sidewalk cycling.

But, to get down to specifics, how realistic is the PeopleforBikes promotion? To what extent does it reflect applicable and appropriate standards?

Let’s look at the reality factor with the image in general.

Below is a comparison of the Google Street View from October, 2011 with PeopleForBikes’ the Photoshopped image. You may click on it to enlarge it and get a clearer view.

Google Street View of Michigan at Keystone

Google Street View of Michigan at Keystone compared with PeopleforBikes Photoshopped image

The school building at the right side is identical, but the other elements of the original image have been enlarged to shift them forward: the traffic signal and utility pole,  buildings on both sides of the street, even the clouds in the sky. The burned-out building on the left is now out of the picture. The worn pavement and faded lane lines of the street have been replaced with a smooth, clean, constant color.

The original Street View shows a blighted neighborhood, heartbreak of the American heartland. and if you open up Street View and look around, you’ll see a number of buildings with boarded-up windows. In the Photoshopped image, the neighborhood is nicely spruced up.

Changing the ambiance creates an air of optimism and helps to sell the bikeway, but on the other hand, the Photoshopped realignment of the streetscape makes this into a fantasy image, not a depiction of any possible future reality.

Now let’s examine the street layout.

PeopleforBikes The artist has placed the street segment which goes off to the left outside the Photoshopped image. The crosswalk in the foreground appears to be in mid-block, unless you notice the traffic signal  mysteriously hanging in a tree at the right, its supporting post  outside the picture.

Another look at the PeopleforBikes image

Another look at the PeopleforBikes image

The image below is a composite, with a part of the Photoshopped image (area with darker pavement) pasted over the unaltered one, and showing the changes in lane widths. The car at the right is the real one from the unaltered image, and the more distant car is Photoshopped. PeopleforBikes The artist has made all of the travel lanes as narrow as the leftmost one. Again, you may click on the image to enlarge it and view it more clearly.

A comparison where the enlarged parts of the image are matched

A comparison where the enlarged parts of the image are matched

The next comparison reveals some issues with dimensioning. I have brought the image of the car in the Photoshopped drawing forward and enlarged it in proportion to the lane width to compare it with the real car. The Photoshopped car is way too big. Also, I have drawn a red line extending forward from the curb line in the next block. That curb line leaves too little width for the right-hand lane — already very narrow — to continue. Assuming that the travel lane in the Street View image is the usual 12 feet wide, PeopleforBikes The artist has reduced it to approximately 9 feet in the nearest block and to 4 feet in the next block — but without any indication that drivers must merge. Because the left lane is used for parking, then only one lane remains usable for through travel.

Comparison of car sizes

Comparison of car sizes

Next, let’s look at the width of the bike lane and proposed separate bikeway.

The near-horizontal red line in the image below extends from one side of the street to the other along the edge of a crosswalk. The other red lines which cross it define the boundaries of travel lanes, a traffic island, the bikeway and the right-hand sidewalk.

Comparison of widths

Comparing widths

If we assume that the right-hand and middle travel lanes in the unaltered image are the typical 12 feet wide and the sidewalk is 5 feet wide, then the two-way bikeway is also about 5 feet wide. This is very tight even for a one-way bikeway. The minimum for a two-way bikeway according to AASHTO [American Association of State Highway and Tranportation Engineers] guidelines 10 feet, preferably with rideable shoulders, and 12 feet are recommended. A 5-foot-wide bikeway between the curb at the sidewalk on one side and a traffic island at the other guarantees congestion, head-on crashes and diversion falls at curbs. Small children and novice cyclists, especially, don’t have the skill or judgment to ride safely under such tight conditions.

But in addition, it might be asked what is the purpose of the 8-foot-wide traffic islands (wider yet in the next block), when the bikeway next to them is only 5 feet wide — and why a two-way bikeway has been placed on the right side — which is the wrong side — of a one-way street.

Finally, let’s look at the only street intersection visible in the Photoshopped image. It is in the deep background. The image below is blurry because it has been enlarged.

intersection in background of picture

intersection in background of picture

Motorists turning right from Michigan Street must cross the bikeway, looking both right and left, and backing up traffic, and then also yielding to traffic on the sidewalk, likely blocking the bikeway. Motorists entering Michigan street must yield first to sidewalk traffic, then to traffic on the bikeway, blocking the sidewalk, and then to motor traffic, blocking the bikeway and possibly also the sidewalk. The white building on the corner hides motorists and bicyclists approaching from the right from each other — already the most hazardous conflict. The  proposed solution to this problem is to paint the pavement in the conflict zone green.

In my proposal with bike lanes on the other side of the street, motorists would block the sidewalk when waiting but would cross both the contraflow and with-flow bike lanes in one move, as is usual when making left turns.

And, I might ask, how would this complicated layout be cleared of snow in winter?

Let me summarize: PeopleforBikes has created put its stamp of approval on a pretty picture which  doesn’t reflect anything real or workable,. This production amounts to a shameless propaganda effort reminiscent of old Soviet publications where images were altered to airbrush out people who had fallen out of favor. The design-by-Photoshop effort shows a profound lack of understanding of, or concern for, issues as fundamental as the necessary width of a general-purpose travel lane, or of a bikeway, or the hazards of wrong-way riding.

Is this an electrically-assisted bicycle?

Elf microcars, from Organic Transit Web site

Elf microcars, from Organic Transit Web site

The photo above is of ELF microcars from the US company Organic Transit.

The ELF is marketed as a velocar — an enclosed, pedal-powered vehicle — but in reality, it is an electrically-powered microcar designed to meet the legal definition of an electrically-assisted bicycle (or tricycle) — like a moped, by having vestigial pedals — and so to be street legal without meeting the requirements for equipment, registration and  driver licensing with a motor vehicle. The microcar is a viable concept, but whether microcars will succeed in the USA, or this one will succeed, is open to question. I do expect that the diversity of vehicle types will increase with time, as I’ve stated in an earlier post on this blog.

Most of the ELF’s power is from the electric motor. It can carry two or three people, or one person an a substantial amount of baggage, but only the one person in front has pedals. There is only a 3-speed geared hub for the pedaler, though a vehicle this heavy needs wide-range gearing if pedal-powered — so, again, the pedaling is secondary to the electric power.

The ELF can charge its battery from the power grid, or more slowly from sunlight, if there is sunlight. Claim is that the ELF travels as fast as most city traffic, but the top speed (limited by proposed electric-bicycle laws) is 20 mph. Legal to use on bike lanes or bike paths? Subject to mandatory bike lane laws? Open to question but it wouldn’t fit them very well — there are problems with microcars for disabled people on Amsterdam bikeways, as illustrated in a previous post. This type of vehicle gets used on bikeways, whether it is legal or not.

Claim “is much safer than a bicycle” is unsubstantiated, as the ELF hasn’t been around long enough to establish a safety record. Three-wheel vehicles, unless very low-slung, are tippy, and the people in the promo pictures are wearing neither seat belts nor helmets.