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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