This article reports on the comparison between traffic prior to the effects of COVID-19 versus after those effects on the Highbury Ave expressway near Commissioners Road in London, Ontario. Data is now available from testing conducted on November 20, 2019 and April 7, 2020. At both times northbound vehicles on Highbury Ave were videotaped passing through a distance of 200 metres approaching the overpass of Commissioners Road, as shown in the figures below.
The view below shows a northbound grey SUV approaching the “Zero” marker at the south edge of the Commissioners Road overpass.
In the November 20, 2019 session a total of 565 northbound vehicles were documented in a half hour along this noted 200 metre distance. In contrast, during the April 7, 2020 session, only 296 vehicles were documented in the same half hour duration. The time of the videotaping was similar, commencing at approximately 1215 hours. Simple math indicates that the drop in vehicle traffic was about 47.6%. The Only logical explanation for this decreased traffic is the effect of the COVID-19 pandemic.
The table below provides a comparison of the data taken from the two videotaping sessions. This table indicated the number of vehicles observed to be travelling at certain speed ranges along with the percentage of vehicles travelling within each speed range. Some observations were “unknown” because at several instances the view of vehicles were blocked from view by large trucks. Thus the totals in the table do not coincide exactly with the total number of observations.
The data from the above table has been rearranged in the form of a chart below, showing the percentages of vehicles in each speed range, contrasted between the two videotaping sessions.
What should be clear is that, although the overall number of observed vehicles was reduced in the April 7, 2020 videotaping, the overall speed of those vehicles was increased. In fact, the average speed of all vehicles in the Nov 20, 2019 session was 99.67 kmh, whereas the average speed in the April 7, 2020 session was 105.26 km/h.
The data was broken down further by examining the average speed of vehicles in the right lane versus the left lane. In the November 20, 2019 session the average speed of vehicles in the right lane was 94.75 km/h whereas the average speed in the left lane was 103.19 km/h. In the April 7, 2020 session the average speed in the right lane was 99.16 km/h, whereas the average speed in the left lane was 110.61 km/h.
In summary, the average speed of vehicles would appear to have increased at a time when the number of observed vehicles had decreased between the two sessions. In particular, there was a huge increase in the number of vehicles travelling between 110 and 115 km/h during the April 7, 2020 session. In November 20, 2019, there were only 5.9 % vehicles travelling in this speed range, whereas in April 7, 2020 that percentage rose to 19.59 %. This indicates that, although the effects of the COVID- 19 pandemic may be favourable in reducing the potential number of collisions, this is counteracted by an increase in overall speed of vehicles and this could increase the potential for certain types of collisions.
An example of a potential problem exists at this Highbury Ave site. The City of London has installed signage informing drivers that lanes will be closed, commencing on April 14, 2020, in preparation for rehabilitation work on the bridge crossing the Thames River located a few hundred metres north of the Commissioners Road overpass. Additional factors to consider is that the on-ramp from Commissioners Road onto Highbury Ave contains a large number of vehicles that are entering Highbury to travel northbound toward the bridge. Data indicates that over the half hour of observation on November 20, 2019, 112 vehicles entered Highbury from this on-ramp. Similarly, on April 7, 2020, 90 vehicles were observed to use this on-ramp. This additional traffic causes slowing of traffic in the right lane of Highbury.
This on-ramp is also very short. A measurement from Googlemaps indicates that it ends only about 142 metres north of the Commissioners Road overpass. While the construction of this interchange is rather old, it is slightly newer than similar interchanges along Highway 401 west of London. A selection of the length of these on-ramps is shown below.
Hwy 401 at Union Road = 366 metres
Hwy 401 at Iona Road = 268 metres
Hwy 401 at Furnival Road = 269 metres
Hwy 401 at Orford Road = 273 metres
Hwy 401 at Victoria Road = 381 metres
Hwy 401 at Kent Bridge Road = 411 metres
The average length of on-ramps from these six examples is 328 metres and this is more than double the 142 metre length of the on-ramp on Highbury Ave at the Commissioners Road overpass. This makes it more challenging for drivers to enter the expressway without interference.
Furthermore, while overall traffic volume has diminished by almost 50 % the data indicates that overall northbound truck traffic has not been reduced to the same degree. In the November 20, 2019 session 42 trucks were observed whereas in the April 7, 2020 session 38 trucks were observed. This results in an increased percentage of trucks from 7.43 % in the Nov/19 session to 12.84 % in the Apr/20 session. These trucks drive primarily in the right lane thus they present an additional problem. With the increase in the numbers of long “truck trains” it becomes more difficult for vehicles to enter an expressway when there is a short on-ramp.
Furthermore, Highbury Ave begins a substantial downgrade northward from Commissioners Road and such downgrades typically result in increased speeds as well as more difficulty in bringing vehicles to a stop. Even on level surfaces it is common for rear-end impacts to occur on the approach to construction zones on high speed expressways. When the City of London closes one northbound lane this will create traffic back-ups. These back-ups are likely to occur along the downgrade and in the vicinity where additional traffic is entering the expressway from the Commissioners Road on-ramp. When these factors are combined with the higher speeds that have been created from the COVID-19 effect, the potential for increased collision rates must be considered. Thus the COVID-19 effect of increasing vehicle speeds may not be a significant problem on its own. However, when it is combined with other factors such as the downgrade and the on-ramp traffic, the combined effect needs to be recognized.
In summary while the COVID-19 pandemic has likely produced an overall reduction in the potential of collisions, the effect never-the-less needs to be examined and understood since unique problems can be generated.