Cyclist Passing Observation #8 From April 14, 2023 On Colborne Street in London Ontario
Cyclist passing actions by drivers of motor vehicles are important to document in detail if we are to understand how we can avoid dangerous interactions when motor vehicles and cyclists come into contact. Knowing this, Gorski Consulting has commenced a detailed study of such passing motions on Colborne St, just north of St James St, in London, Ontario. The study involved the creation a matrix of markers on the road and then taking video of the cyclists and motor vehicles that pass through the markers. This zone of observation takes place over a distance of 50 metres.
Several articles have already been written about this study. Fourteen instances of cyclist passing motions have been identified as shown in the table below. Articles have already been written about the observations from the first two incidents “Apr 14-1” and “Apr 14-2”. We will now proceed to discuss a third observation “Apr 14-8”.
The table below shows the lateral position of the cyclist as he travelled through the 50-metre zone of observation. Thus the cyclist crosses the Zero marker at timecode 01;09;56;50 and then we see that he generally rides in an area that is less than 1.0 metres west of the concrete gutter. Overall his average position is 0.78 metres west of the concrete gutter. This distance appears to be less than the frame shown below where it suggests that the cyclist is riding substantially further from the concrete gutter.
The scenario in the “Apr 14-8” involves a black Audi car which passes a cyclist just before the traffic units reach the area of observation. So the first frame, taken from video, is shown at the top of the article and we can see the front portion of the Audi passing through the Zero marker at the timecode of 01;09;54;14. The figure below shows the same timecode but looking southward, and here we can see that the Audi has already passed the cyclist who has not reached the area of observation. We can note that the Audi has moved well over the roadway centreline. Our analysis indicates that the right front tire of the Audi is 2.90 metres to the west of the concrete gutter of the northbound lane.
In the next figure below we can we the cyclist crossing the Zero marker thus he is just entering the 50-metre zone of observation. Our analysis indicates that the cyclist is riding at 0.85 metres west of the concrete gutter. It also shows that the Audi has already passed the 25-metre marker.
The next figure below shows the position of the Audi at timecode 01;09;56;47 just as the Audi is crossing the 25-metre marker.
In the next figure below we see the position of the cyclist as he crosses the 25-metre marker at timecode 01;10;01;15. At this time the figure shows that the cyclist is located 0.60 metres west of the concrete gutter. The Audi is no longer in view because it has already moved well north of the cyclist.
In the next figure below we can see that the Audi crosses the 50-metre marker at timecode 01;09;58;47. At this time the right front tire of the Audi is located 1.50 metres west of the concrete gutter. So, when the Audi was at the Zero marker it was located 2.90 metres from the concrete gutter so it has moved back into the northbound lane by 1.40 metres.
In the next figure below we see the status of the cyclist as he passes the 50-metre marker at timecode 01;10;05;14. Here the cyclist is positioned about 0.75 metres west of the concrete gutter.
These figures shown above can be used to examine some further details about this scenario. For example, we can calculate the average speeds of the traffic units. With respect to the Audi it took 2.88 seconds to travel the 25 metre distance between the Zero marker and the 25-metre marker. So its average speed within this zone was 8.68 metres per second or 31.3 km/h. Similarly the cyclist travelled the same distance in 4.42 seconds so its average speed was 5.66 metres per second or 20.36 km/h. Thus the difference is speed of the Audi and cyclist was not large at this first half of the observation zone.
In the second half of the observation zone the Audi travelled from the 25-metre marker to the 50 metre marker in 2.0 seconds so its average speed was 12.5 metres per second or 45 km/h. So the Audi increased it speed during the latter portion of the zone of observation. With respect to the cyclist, he travelled the latter 25 metres in 3.98 seconds so its average speed was 6.28 metres per second or 22.61 km/h. So the cyclist also increased his speed during the latter portion of the observation zone.
Changes in speed matter. Drivers of passing motor vehicles develop a sense of when they should pull out to the left to pass a cyclist by judging their own speed as well as the speed of the cyclist. The driver may steer back into the traffic lane based on that expectation. If a cyclist’s speed suddenly increases the driver of the passing vehicle may misjudge when he should steer back into the lane and a potential contact could occur in some rare instances. Such instances are rare because, generally, cyclists cannot generate a very high acceleration in a short distance so the difference in speed of a cyclist would not be expected to be high in such short distances.
The ultimate purpose of this study is to consider what these scenarios may be like once a painted cycling lane is fully created by the City of London. How will the lateral positions of motor vehicles and cyclists change when the painted cycling lane exists? Will there be a greater potential for motor vehicle and cyclist contact? Will the defined cycling lane improve the safety of cyclists? These are the types of questions that need to be studied in an objective and unbiased fashion. It is the intention of Gorski Consulting to write further articles on other passing motions so that some understanding of the issues can be gained by anyone wishing such information.
Nothing More Comforting Than Being Locked Out of One Own’s Website
It was reported to me in a useful dialogue box that the owner of the Gorski Consulting website had temporarily locked me out for some unknown reason. The problem is that I am the owner of the website and I did not ask to lock myself out of my own website. The lock-out has existed for a number days until this evening when suddenly I was released from lock-out prison.
These are the modern times when strange things occur as we grapple with crooks who want to damage or steal someone’s website information. Maybe life was a little more simple in earlier times when, if you had something to say, you could stand on a soap box or prepare a presentation to a library or local neighbourhood group. Crooks who heckled you could clearly be seen in the audience. Now-a-days one never knows whether someone takes control of your website and requires a ransom. It reinforces to me that there are really a lot of crooked and wicked people out there who are hidden by the anonymity of the internet. You can basically do as you please without ever getting caught because no one can find out who you are. One of the best controls we ever had against crooks is that, once they were identified, they were visible to us all. That seems impossible now in our brave new world.
Cyclist Passing Observation #2 From April 14, 2023 on Colborne Street in London Ontario
Documentation of motor vehicles passing cyclists on Colborne Street in London Ontario is a time consuming affair. Yet such data may help to clarify how cyclists are struck and what actions may be needed to prevent such occurrences.
As reported in previous articles on this Gorski Consulting website, efforts have been made to gather instances where cyclists are passed by motor vehicles at the site of Colborne Street just north of St James Street in London, Ontario. After 3 video sessions on April 12, April 14 and June 8, 2023, a set of 14 cyclist observations were made where these cyclists were passed from behind by motor vehicles. A table of these occurrences was shown in previous articles and is displayed once more below.
We began detailed descriptions of these instances in a previous article published on July 22, 2023. The focus of that article was the first passing motion shown in the above table. The observation labelled “Apr 14-1” which involved a white car passing a cyclist just north of the 50-metre observation zone. Since the passing motion occurred outside of the range of the video cameras there was less relevant information that could be passed on about the characteristics of the motion.
The present article will now focus on the second observation (“Apr 14-2”) wherein a cyclist was passed by a white minivan in the vicinity of the 5 and 10-metre markers of the 50-metre site. Because this occurred within the range of most video cameras we are able to provide more useful information.
The table below shows the travel path of the cycle as it passed each of the 5-metre markers between the Zero marker and the 50-metre marker. This data shows that, in general, the cycle stayed very close to the concrete gutter of the lane. On average its position was 0.45 metres west of the concrete gutter.
The figure at the top of this article shows the position of the cyclist at timecode 00;15;52;24. That view was looking northward. The same time frame is shown in the figure below except that the view is looking southward. What we are seeing in both figures is that the front tire of the subject cycle is crossing the “Zero marker” which is at the south end of the 50-metre zone of observation. What is possible to see in the figure below is that a white minivan is approaching the cyclist from the rear and that a passing motion is about to take place.
The next figure below shows the cycle as its front tire is crossing the 5-metre marker. Here we can also see that the white minivan is just behind the cycle. The views from four other video cameras have been minimized and are shown at the bottom of the figure.
The next figure below is at the same time frame as the figure above but it is a view looking southward. We can see that as the van is about to make its passing motion its left side tires have crossed over the centre-line of the road. There is no opposing (southbound) traffic so the driver of the minivan can easily cross the centre-line without being concerned with interfering with opposing traffic. Such a circumstance does not always exist. At times a driver may decide to pass a cyclist and then discovers that he/she misjudged the speed of opposing traffic and entrance into the opposing lane becomes risky.
In the next figure below we see the situation as the right front tire of the minivan crosses over the 5-metre marker. At this time the outer edge of the right front tire is located about 2.05 metres west of the concrete gutter of the northbound lane. Meanwhile it can also be seen that the cycle is located just north of the 5-metre marker and it is about 0.35 metres west of the concrete gutter.
In the next figure below we see the scenario when the front tire of the cycle crosses the 10-metre marker. Note that the left-rear tire of the minivan is west of the roadway centreline yet it also appears to show that the minivan is at an angle to the length of the road and it is being steered back into the northbound lane. This is at a time when the minivan is side-by-side with the cycle. This can be a complicated situation. If opposing traffic exists the minivan driver may be forced to steer back into the northbound lane earlier than initially intended. The speed of the cyclist is also a complication since the passing motion can be completed earlier when the cycle is travelling slowly. If the minivan driver misjudges the speed of the cycle it is possible that steering back into the northbound lane could interfere with the travel path of the cyclist.
In the next frame below we see the situation as the right front tire of the minivan crosses the 25-metre marker. At this time the right front tire is about 1.6 metres west of the concrete gutter whereas, less than 2 seconds earlier, it was over 2 metres west of the gutter. So the van has moved substantially to right, back into the northbound lane. At the same time we can see that the cyclist is positioned approximately halfway between the 15 and 20-metre markers.
In the next figure we see the scenario when the cycle reaches the 20-metre marker. At this time the right front tire of the minivan is crossing the 30-metre marker. The minivan has now fully returned into the northbound lane.
In the figure below we see that the front tire of the cycle crossing the 25-metre marker at the timecode 00;15;56;43. At the same time the rear end of the minivan is just crossing the 40-metre marker.
In the figure below we can see the right front tire of the minivan passing the 50-metre marker and its outer edge is located 1.00 metres west of the concrete gutter. This view also shows the cycle which is passing the 30-metre marker. So the minivan has moved over 1.00 to the right in comparison to its position few seconds earlier.
In the final figure below we see the front tire of the cycle passing the 50-Metrre marker at timecode 00;16;00;55. At this time the front wheel is located about 0.40 metres west of the concrete gutter.
Analysis and Discussion
While much concern is expressed by many about the number of times that cyclists are struck while being passed by motor vehicles, little or nothing has been done to study such scenarios in objective detail to understand what factors may be at play. In most instances where a significant injury or death has resulted police attend the collision, close the roadway and complete a reconstruction of the incident. Rarely is it revealed to anyone that the results of those police reconstructions are never made available to the public. Any objective analysis and understanding of such an incident is permanently lost and allowed to repeat itself because nothing is learned from the tragedy. The only way of obtaining any useful objective evidence is to conduct observations of naturalistic behaviours such as is being done in this present article.
By observing the timecodes when the cyclist and minivan pass by the various roadway markers we are able to identify important information such as the speed of the vehicles, their lateral locations on the road and their relationship to each other.
For example we can examine the speed of the cyclist. At timecode 00;15;52;24 the cycle is crossing the Zero marker. At timecode 00;15;56;43 the cycle is passing the 25-metre marker. Thus in 4.32 seconds the cycle has travelled 25 metres or at an average speed of 5.79 metres per second or about 20.83 km/h. That is slightly higher than the typical riding speed of an average cyclist.
Next we can examine the speed of the cyclist in the second part of its travel, between the 25 and 50-metre markers. The cycle crosses the 25-metre marker at 00;15;56;43 and it crosses the 50-metre marker at 00;16;00;55. So it has travelled 25 metres in about 4.2 seconds, or 5.95 metres per second or 21.43 km/h.
Similarly we can examine the speed of the minivan. The van crosses the Zero marker at 00;15;53;06 and it crosses the 25-metre marker at 00;15;55;27. Thus the minivan travelled the first 25 metres in 2.35 seconds, or 10.64 metres per second or 38.30 km/h. Then it crossed the 50-metre marker at 00;15;57;42, so it took 2.25 seconds to travel the second distance of 25 metres. The minivan’s average speed in the second half of the 50 metre distance was 11.11 metres per second or 40.0 km/h.
So the minivan’s speed was a little less than 20 km/h higher than the cycle’s speed. This would mean that the passing motion had to occur over a longer time than if the difference in the speeds of the vehicles was greater.
This review has shown that the minivan driver passed the cyclist when the right side of the van was about 2.05 metres from the concrete gutter. And the cyclist remained riding close to the gutter with an average of only 0.45 metres west of the gutter.
According to page 15 of Book 18 (June 2021 version) the design dimensions of various cycles are shown in the figure below.
The physical width of a cycle is to be assumed to be about 0.75 metres. Thus in our example, if the centre of the cycle is at 0.45 metres west of the concrete gutter we need to add half of the 0.75 metres to determine where the cycle’s left side might be, It would be 0.45 + 0.38 = 0.83 metres west of the concrete gutter.
And we also know that the outer edge of the right front tire of the minivan does not represent the actual furthest extent of its structure to the right. Often it is add-ons such as the right exterior mirror that determine the full extent of the minivan’s structure. We have not proceeded to find out how far the right edge of the exterior mirror might protrude beyond the right edge of the tire. However, for now, we might use a value such as 0.30 metres. Thus the extent of the minivan’s protrusion to the right would be reduced from the 2.05 metres to about 1.75 metres west of the concrete gutter. So using this approximation we might say that the lateral distance between the right side of the minivan and the left side of the cycle would be about 1.75 metres minus the 0.83 metres, or about 0.92 metres. Provincial regulations state that a passing motor vehicle must stay about 1 metre away from the cycle it is passing so one might consider that the minivan was not fully 1 metre away from the cycle, as required. And we can consider that the cycle was riding close to the gutter while the average from our observations is about 0.71 metres west of the concrete curb. It can be seen that even with a fairly wide northbound lane it would be a challenge for the driver of a motor vehicle to stay within the northbound lane and still pass a cyclist according to the requirements of provincial regulations. The vehicle would be forced to ride into the opposing lane and that might not always be possible if opposing traffic exists. So the driver must be selective and alert as to when to chose the proper moment to pass a cyclist.
These are the kinds of understanding that become possible when conducting naturalistic observations of passing motions of cyclists. While this is time consuming it also produces unbiased, objective data that can help the general public in understanding the details of these events. While we all like to express our hard felt opinions it is through reference to this objective data that our opinions can be grounded in reasonable expectations.
Details of Motor Vehicle Passing Motions of Cyclists
Stress, anger and accusations abound these days as cyclists find themselves vulnerable to being struck by vehicles operated by seemingly uncaring drivers. While impacts occur it is rare that anyone can state with any degree of accuracy how and why the impacts occur. For example the details of investigations conducted by police are never available for the public’s consideration. So, while injuries and deaths occur, nothing of any usefulness is available to be used to educate both cyclists and motor vehicle drivers as to how to avoid these incidents.
Gorski Consulting has been involved in the reconstruction of many motor vehicle collisions, some of which have involved serious cyclist collisions. As the principal of the firm, Zygmunt Gorski, is now in the process of retiring. Yet the methods of detailed analysis that were developed over many years of study can be applied to provide some help to the general public rather than to paying clients. As such Gorski Consulting has recently been involved in a number of documentations focused on improving the public’s understanding of collisions and how they occur. With the increasing numbers of cyclists riding on roadways of varying levels of safety, Gorski Consulting has commenced a number of studies focused on providing detailed, objective and unbiased data that will be available for anyone to evaluate and analyse.
One of our projects has involved a section of Colborne Street in London Ontario where the City of London is preparing to create a painted cycling lane north of Oxford Street. Some concern has been expressed by some cyclists that painted cycling lanes do not provide the necessary level of protection and that the cycling lane should be one with a protective barrier between cyclists and motor vehicle traffic. Because of such concerns we determined that this would be a good opportunity to conduct some detailed observations of how cyclists and motor vehicles interact at the site.
In the fall of 2022 Gorski Consulting commenced three sessions of observations with the use of synchronized, multiple video cameras. These efforts resulted in calculations of vehicle speeds and volumes and these data were compared to the recommendations of Book 18 of the Ontario Traffic Manual. It was felt however that this study was not enough.
It was decided that a very useful study would involve documenting the lateral travel paths of motor vehicles and cyclists and they passed through an observation area of 50 metres. Within this zone a matrix of markers was placed at 5-metre intervals and at each station additional markers were placed lateral to the northbound lane. These efforts would provide objective data regarding how cyclists and motor vehicles interact before a painted cycling lane is created. Three such sessions were conducted on April 12, April 14 and on June 8, 2023. Once the City of London created the painted cycling lane it was deemed that a second set of sessions would capture if and how the lateral paths of all traffic units had changed.
At present our analysis of the video projects from the three video sessions has allowed the capturing of a number of northbound cyclists. Our goal was to examine these instances and take a subset of those where motor vehicle passing motions occurred. As a result fourteen observations were identified where such passing motions were in effect and these observations are shown in the table below.
Note that no passing observations were identified from the first video session of April 12, 2023. Six observations were found from the video session on April 14, 2023 and another eight observations were captured from the June 8, 2023 session.
Detailed study of these actions is complicated and time-consuming. It requires examining views from several video projects that contain different mixes of video cameras since not all views can be crowded into a single project. Yet the results can be quite enlightening to those who may be interested. Thus in this article we will focus on a single observation of a passing motion to show what can be learned. The observation we will focus on is the first one in the above table. Even though a passing motion did not occur with the 50-metre observations zone we can see how the white car approached the cyclist, what speeds were involved and other interesting facts.
Exploration of a Cyclist Passing Motion
We begin this study by looking at the contents of the Premiere video project containing views from five video cameras. The view at the upper left shows that a northbound cyclist is seen crossing the Zero marker at the timecode 00;11;44;49.
The table below shows how the cyclist moved through the site as he passed by each of the 5-metre markers. The numbers are with respect to the edge of the east concrete gutter which is the Zero for all lateral positions. So, at the Zero marker the cycle’ front tire passed through at 1.00 metres west of that concrete gutter. One can see that the cyclist then started to ride a little closer to the concrete gutter as we see values such ass 0.80, 0.70 and even 0.65 at the 50-metre marker. On average the cycle rode about 0.78 metres west of the concrete gutter.
The next figure shows the scenario at 00;11;50;11 which shows an elapsed time of 5.37 seconds in which the cyclist has managed to reach the 30-metre marker. Simple calculations indicate that the cyclist’s average during this time must be about 20.11 km/h.
The next figure shows that a white car makes a left turn from eastbound St James Street and begins to travel northbound on Colborne. At this same time the cyclist has managed to reach the 40-metre marker.
In the next figure below we see that the white car has reached the Zero marker at a timecode of 00;11;52;14. Looking at the position of the car’s right front tire we can see that it is riding over the 1.00 metre marker. In other words the car is 1.00 metres to the west of the concrete gutter. We will want to observe if, and how, this lateral position of the car changes as the vehicle approaches the cyclist.
In the next figure we see that the cyclist has reached the 50-metre marker at a timecode of 00;11;53;30. The 50-metre marker represents the end of the zone of observation so will have little information about what happens after the vehicles exit this zone. However we can calculate the average speed of the cyclist between the 30 and 50-metre markers and this happens to be about 21.69 km/h, or just slightly faster than the 20.11 km/h that the cyclist was travelling as he entered the area of observation.
Meanwhile we can also calculate the speed of the white car. Below we can see it crossing the 20-metre marker at timecode 00;11;53;47. And we know that it crossed the Zero marker at timecode 00;11;52;14. Thus it took the car 1.55 seconds to travel the 20 metres and its average speed was 46.45 km/h.
We also note in the figure below that the white car passes the 50-metre marker at timecode 00;11;55;53. So the car’s average speed between the 20 and 50-metre markers was 51.43 km/h. At the time that the car passes the 50-metre marker its right front tire crosses at about 1.0 metres from the concrete gutter.
By zooming in on the northward view from the camera at the Zero marker we are able to see the lateral position of the white car at the timecode of 00;11;55;53 and this is when the car is crossing the 50-metre marker. The view below shows that the white car is at a slight angle to the west and therefore it is likely proceeding to pass the cyclist.
Although we do not know the precise location of the cyclist when the white car is at the 50-metre marker we can extrapolate from the fact that between the 30 and 50-metre markers its average speed was 21.69 km/h. Thus in the time that the white car travelled 30 metres in a time of 2.06 seconds.
At an average speed of 6 metres per second, in 2 seconds the cyclist would travel about 12 metres. Thus at timecode 00;11;55;30 the cyclist would in the vicinity of 62 metres north of Zero. Meanwhile at a timecode of 00;11;55;53 the white car is passing the 50-metre marker, which is about 0.38 seconds later than the time quoted for the cyclist so the car would need to be reversed by 5.4 metres in that time. The bottom line is that the cyclist would be at 62 metres and the white car would be at about 44.6 metres when the car is seen steering into the middle of the roadway in preparation to pass the cyclist. So this information gives us an idea as to when a driver might begin to steer around a cyclist who is travelling about 21.69 km/h. And this would occur when the car was about 17 to 18 metres behind the cyclist.
Even though the passing motion occurred just north of the observation area, we are still able to conduct some calculations to indicate how the passing motion develops. Looking at the rest of the observations in the table above there are several passing motions that occurred within the observation area and these will provide useful information. Because these analyses are time-consuming it requires someone to volunteer to take on this assignment, examine all the observations and then come up with some ideas as to how these cyclist versus motor vehicle interactions occur. Gorski Consulting is certainly willing to provide these video projects to anyone who would wish to pursue this research.
Painted Cycling Lanes – An Evaluation of Their Safety Risks
Not all roadways are the same. When considering the application of paint to produce a designated cycling lane there has to be consideration taken to many specifics about a site’s characteristics. Book 18 of the Ontario Traffic Manual is a comprehensive, 364 page document, completed in June of 2021, that attempts to guide “practitioners” about what matters with respect to most issues of cycling infrastructure. While its recommendations appear to be generally sound, pitfalls remain, particularly if its advice is misconstrued or deliberately ignored.
A recent evaluation was made by Gorski Consulting with respect to the conditions existing on Colborne Street near St James Street in London, Ontario and whether it would be reasonable to create a painted cycling lane. In 2022 the City of London announced that it would be proceeding with such a painted cycling lane. Some cyclists were concerned and requested a protected cycling lane instead. As a result of conducting several sessions of multi video-camera documentations we identified the traffic volume and the operating speed of vehicles at the site and then examined the recommendations from Book 18 of the Ontario Traffic Manual as shown below.
The rectangle of orange in the above figure lies in a semi-green zone where, according to Ontario’s guidelines, the installation of a separated (protected) bike lane was not obviously necessitated based on vehicle speed and traffic volume alone.
However Book 18 discusses a number of additional recommendations. While not complete, the following two figures provide some indication of what practitioners might need to consider beyond the speed and volume of motor vehicles.
While the above list of considerations are helpful they are not complete, and there lies the problem.
For example Book 18 contains a discussion about “motor vehicle” traffic volume. In other words if there are a lot of motor vehicles travelling on the roadway then this could trigger the need for a protected lane. But this makes little sense if there is no consideration of the “cyclist” traffic volume. So if the site contains an average of 10 cyclists riding through it the potential for dangerous interactions with motor vehicle traffic would be low regardless of the actual volume of motor vehicles on the road. Conversely, if the site contains an average of 50 cyclists riding through it then the potential for dangerous interactions with motor vehicle traffic increases. So it makes little sense to identify the motor vehicle traffic volume alone without also identifying the cyclist traffic volume.
Another weakness of the guidelines in Book 18 is that they do not place much emphasis on the width of a travel lane as an important consideration. It would seem that a lane that is only 3.0 metres wide does not generate sufficient concern where a lane width of 4.0 metres might be more realistic in many applications. Clearly, narrow lanes are likely to produce a greater potential for dangerous interactions between cyclists and motor vehicles and this needs to be spelt out.
Additionally the above advisements from Book 18 provide minimal mention about the quality of the road surface as being a potential factor in creating dangerous interactions between cyclists and motor vehicles. In many jurisdictions the right edges of travel lanes contain areas of broken asphalt, dangerous longitudinal splits in the surface, or there may be debris left lying in the area where cyclists must travel. A cyclist’s balance can be affected by these road surface conditions. Also the rider may purposely steer away from these areas and into the path of passing traffic. So if the advisements of Book 18 are to be more relevant they must include a better discussion of the hazards posed by road surface conditions.
Furthermore, as shown in the photo at the beginning of this article, roadway curves are areas where dangerous interactions can occur between cyclists and motor vehicles. It is known that drivers of motor vehicles are not perfect in steering around horizontal curves and this causes motor vehicles to stray out of a lane. Conversely cyclists also experience the same problem in keeping their cycles in a consistent lateral path through a curve. This factor must be considered as a contributor to dangerous interactions between cyclists and motor vehicles. Again Book 18 should place a greater emphasis on this point.
The characteristics of the cyclists themselves must also be taken into consideration. Cyclists who ride with various cargo that increases the lateral width of the cycle within a lane should be taken into account for obvious reasons. From many years of observations by Gorski Consulting a variety of unconventional characteristics have been noted when cyclists carry cargo, sometimes increasing the width of the cycle and rider to dangerous proportions. Book 18 could discuss this with greater emphasis.
Areas of vertical curves must also be taken into consideration. If a road segment contains a significant vertical curve (upgrade) it is likely that a certain percentage of cyclists will have difficulty climbing such a hill and the speed of the cycle drops. This slower speed is an indicator that a cyclist is having difficulty climbing such a hill. While travelling slowly the lateral path of a cycle will become more unpredictable as the cyclist’s efforts cause the cycle to sway and change direction. Such difficulties are accentuated in those who are already weaker or inexperienced riders. While anyone is allowed to ride a cycle this means that there is a large difference between athletic/experienced riders and those who may be elderly or young who may have difficulty dealing with more significant roadway slopes. Again more emphasis could be placed in Book 18 to highlighting these important geometric design elements as potential contributors to dangerous conditions.
In the view of Gorski Consulting documentation of naturalistic vehicular motions is an incredibly important step toward understanding road safety conflicts. Over the years Gorski Consulting has completed numerous such documentations throughout Southern Ontario. It is through this process that we come to understand what is actually occurring on roadways versus relying on the reported results from studies by unknown authors at locations that may not be representative of the conditions in Ontario. When you conduct your own studies and complete the analysis of what is documented you are at a better level of understanding of the issue you wish to address.
Thus in our cyclist studies we conduct thorough video observations of many factors that are not normally addressed. Our latest work on the Colborne Street site involves tracking the travel paths of cyclists, transit buses, other oversize vehicles and light passenger vehicles such as cars, SUVs and minivans. As in pervious studies this involves lying a matrix of markers in the lane and then obtaining video of vehicles passing through these markers. We can then look at things like the average lateral position of these units within the lane and how much variance exists in those paths. Such work is extremely important as a substantial number of serious collisions occur when cyclists are struck from behind by motor vehicles attempting to pass them.
Our most recent re-visit to the Colborne Street site (July 16, 2023) indicates that the City of London has commenced its work to create the cycling lanes on both sides of the road. Preliminary paint has been applied by the City and therefore we are able to examine how the site will look like when the cycling lane is completed.
Measurements by Gorski Consulting at the Colborne St site indicate that the northbound lane just north of St James Street was about 3.85 metres in width if one includes the 0.46 metre wide concrete gutter. Without the gutter the lane would be 3.39 metres wide. For the purposes of documenting the lateral paths of traffic units it was decided that the junction between the concrete gutter and the asphalt surface of the lane would be a good reference point.
Upon completing three video sessions at the Colborne St site, average travel paths have been calculated for the four categories of traffic units discussed above. These data are shown in the table below.
So the above table identifies the Average lateral location of vehicles as they passed through the 50-metre distance where roadway markers were applied. As an example, the London Transit Commission (LTC) buses rode through the site at an average of 0.87 metres west of the edge of the concrete gutter. Precisely, the outer edge of the right front tire of the bus was identified. Similarly the outer edge of the right front tires of the “Other Over-Size Vehicles” and the “Light Vehicles” were similarly documented. For Cyclists the centre of the front tire was used as the point of documentation.
Looking at the Standard Deviation of these data it would suggest that the lateral paths of LTC Buses were more variable that the other three categories, but that is not the case. Only 18 observations of LTC Buses were documented. In one of those observations from June 8, 2023 the bus travelled extremely outside of the regular path such that the right front wheel was positioned along the roadway centreline for several locations along the road. This occurred because a delivery van had come to a stop, blocking the northbound lane and the bus moved over across the centreline in order to pass the stopped vehicle. This skewed the results. If that single observation was removed from the table then the LTC Bus Average would be 0.76 and the Standard Deviation would have been 0.1677, So the Standard Deviation of the TLC Buses category would actually be the lowest of the four categories, not the highest.
Once the City of London has completed its creation of the cycling lanes the next step will be to conduct several video sessions to identify how the travel paths of the four vehicle categories have changed. This process may also illuminate how often cyclists or motor vehicles stray out of their designated lanes. We may also obtain useful information regarding how motor vehicles pass cyclists.
Colborne Street contains a transit bus route and this could be a complication for keeping cyclists safe. It can be noted from the above table that the right side of transit buses take a path that is not much different from the path of cyclists. The right front wheels of buses are located at about 0.76 metres west of the concrete gutter while the front wheels of cyclists are located 0.69 metres from the gutter. There are additional attachments on transit buses that protrude to the right beyond the outer edge of the right front wheel. Exterior mirrors would be one example. And similarly the left side of a cyclist/cycle will be positioned further to the left than the centre of the front wheel. So there is potential for conflict to exist. One needs to look at the data however before evaluating the safety risk involved and it is hoped that the data will be a useful source of further knowledge in this area.
Resources such as Book 18 of the Ontario Traffic Manual are used by many in municipal transportation departments in Ontario to conclude that cycling lane characteristics are appropriate because the manual says so. While such resources can be helpful they can also lead to dangerous conclusions if the analyst does not consider that every roadway is unique with unique challenges. Book 18 cannot encapsulate every possibility where dangers may exist. Unfortunately a solid understanding of collision causation can only be obtained from detailed collision reconstruction studies and these are rarely available to the typical municipal analyst, Blind reliance on large data from resources such as police reports means that sometimes analysts fail to appreciate that the vast majority of police reports are completed by officers with minimal expertise in collision reconstruction. Thus systemic error exists in these large data files which is sometimes not understood or detected. A properly trained analyst should understand how and why these systemic errors become entrenched in the data. With such an understanding an analyst can be better prepared to evaluate collision data with caution where caution is needed, and not race to a blind conclusion on a safety issue because the manual says so.
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