What speed are eastbound motor vehicles travelling on the Blackfriars Bridge in London Ontario, where the maximum posted speed is just 20 km/h?

Interest in the use of the historic Blackfriars Bridge in London, Ontario became heightened when the City of London decided to open the bridge to eastbound motor vehicle traffic in November of 2021. Pedestrians, cyclists and other users had grown used to having the bridge all to themselves during the incidence of the Covid 19 pandemic and were not happy with the change.

While opinions flourished no actual data was made available to support one point of view versus another. As a result Gorski Consulting decided to conduct a traffic study that would provide some base information to all involved.

Speeding eastbound vehicles (approaching the camera) were documented as they crossed Blackfriairs Bridge over a series of four videotaping Sessions. Using the west edge of the pedestrian crossing (foreground) speed was documented over three segments of distance approaching the crossing.

The volumes of various traffic units at the site were reported in several website articles on the Gorski Consulting website. At present four videotaping Sessions have been completed and more may be added in the future. The present article will study the speeds of eastbound vehicles at the site.

The observed speeds of eastbound motor vehicles was frequently interrupted by other users of the site therefore it was not useful to provide average speeds of all vehicles. Instead we focused on those vehicles which we labelled “High Speeders”. High Speeders were defined as those whose travel time was 1.5 seconds or less within the 10 metre distance approaching the pedestrian crossing for the Thames Valley Parkway. Why this definition was chosen cannot be discussed here due to the complexity of the issue but may be addressed in another future article.

The table of results is shown below, summarizing all four videotaping sessions that have been completed to this date. An explanation of the table contents will follow.

Speeds were documented over 3 segments of roadway commencing westward from the west edge of the pedestrian crossing at the Thames Valley Parkway. The pedestrian crossing is located at the east end of the Blackfriars Bridge. The first segment was over a 10-metre distance progressing westward from the west edge of the pedestrian crossing, as explained in the photo below.

The next two road segments were each 25 metres in length. So, commencing westward from the 10-metre mark, paint markings were made at 35 and 60 metres west of the pedestrian crossing. An example of the paint marking at the 60 metre distance is shown in the eastward view of the photo below.

A camera was also placed on the north railing of the bridge (at 35 metres west of the pedestrian crossing) pointing in an eastward direction toward the pedestrian crossing, as shown in the photo below.

View looking east from just west of the camera at the 35-metre marker. The camera pointing eastward provided views of the brake lights of eastbound vehicles.

We can narrow the study further by noting the four vehicles, from all four Sessions, that travelled the 10 metres toward the pedestrian crossing in less than one second. This data is shown in the table below.

Three of the vehicles shown above are from Session #2 which took place on the afternoon of Friday, June 17,2022. No vehicles were noted to be travelling at these speeds in Sessions 1 and 3.

It can be noted that in two of the four instances the vehicles actually increased their speed in the 10 metre distance of approach to the pedestrian crossing in comparison to their speeds in the preceding segments. In those two observations (#44 and #142) the average speeds were well above 40 km/h (42.35 and 46.75 respectively). While these speeds may appear to be rather slow in terms of highway or even urban streets the special conditions of this site involve very limited lines of sight. If a pedestrian, cyclist or other vulnerable person were to enter into the path of these motor vehicles there would most likely be some serious injury consequences.

Addendum

This addendum is included to provide some explanation about the total observations of motor vehicles in the table of four Sessions noted at the top of this article. That table is reproduced again below.

The 149 observations in Session #2 is lower than the total (158) mentioned in previous tables because there was a time delay before all the cameras were put in position be able to document the vehicle speeds. So, although the counting of individual motor vehicles began at 1532 hours, a number of minutes passed before the cameras were set in place to be able to document their speeds. Thus the speed of the first 9 vehicles were unable to be calculated.

Also, in previous articles the total number of vehicles that were documented in Session 1 (77) and Session 2 (157) were incorrect. Upon further analysis during vehicle speed calculations it was discovered that one additional vehicle existed in each of those two Sessions. So the correct motor vehicle total for Session #1 is 78 and for Session #2 is 158. And again, the reason why only 149 observations are shown in the above table is because we could only obtain speed calculations for 149 of the 158 vehicles that were observed.