Highway 401 Safety Issues – Veering Out of a Travel Lane
An unintended veering out of a travel lane can be the cause of traffic disruptions that ultimately lead to a collision. Collision Reconstructionists who examine the post-collision evidence are rarely able to detect the physical evidence of such an action because, for the vast percentage of cases, no physical evidence exists.
To get a handle on how often such veering occurs Gorski Consulting has examined the videotaped observations of traffic from four sessions at three sites along Highway 401 in South-western Ontario. As mentioned in previous posts, these videotaping sessions were conducted this past fall using multiple video cameras over a period of 2 hours in each session.
During an initial session on October 30, 2018 it was observed that a substantial number of vehicles were veering to the right, out of the right lane, the drivers would then react and bring the vehicle back within the right lane. An obvious example of this occurrence is shown in the following sequence of still frames taken from the video of a camera positioned on the overpass of Westminster Drive and looking into the westbound lanes of Highway 401.
Frame 1 – A westbound car is seen in the background of the right lane approaching the camera.
Figure 2 – The westbound vehicle begins to veer into the terminating lane adjacent to the right, through lane.
Frame 3 – The westbound vehicle establishes itself fully in the terminating lane.
Frame 4 – Within 100 metres of the end of the terminating lane the driver begins to return the vehicle to the right, through lane.
Frame 5 – The vehicle continues to travel back into the right, through lane.
Frame 6 – The vehicle returns fully into the right, through lane.
Frame 7 – The vehicle leaves the view of the camera while continuing to travel in the right, through lane.
Thus this became the reason to look at the other sessions and document all those incidents where such veering was observed. The table below is a summary of those observations for the three sites and four videotaping sessions.
Generally one could conclude that about 1 to 2 percent of vehicles in the right lane of Highway 401 will veer out of the lane in an observed distance of about 400 metres.
This can also be expressed in terms of the actual numbers of veering vehicles observed per hour. As noted in the table above the session at Graham Road provided the least number of observations of veering per hour. Only 15 vehicles were observed to veer out of the right lane in a time of two hours. So the frequency would be about 7 to 8 vehicles per hour.
In contrast the two sessions at the Westminster Ave site provided between 36 and 43 observations for two hours or about 18 to 21 veering motions per hour.
The Westminster Drive site is interesting because there is a curve that terminates between the 400 and 300 metre markers of our testing. Historically loss–of-control collisions have been more prominent at the end of such curves. Thus it is not surprising that the Westminster site would generate more veering vehicles because of the presence of the curve.
We have now discussed a number of issues relating to the safety of Highway 401 between Tilbury and London, Ontario. This length of highway is where the new High Tension Cable Median Barrier is being installed by the Ontario Ministry of Transport. In earlier posts we have shown how many large trucks drive through area. During weekdays the percentage of transport trucks may approach 50%. During weekends and holidays that percentage is less. We have also examined the difference in speed between trucks that are limited to a maximum of about 105 km/h and non-trucks that travel at an average speed of 116 to 119 km/h. And we have also presented data indicating that over 18% of drivers allow a gap of less than two seconds between the front of their vehicle and the rear of the vehicle they are following. These are some of the data that provide a glimpse of the safety problem on Highway 401.
Hwy 401 – Median Crossover by Truck at Downie Road
Another median crossover incident occurred on Highway 401 just east of Downie Road on December 17, 2018. This is significant because the involved tanker truck struck the High Tension Cable Median Barrier (HTCMB). The HTCMB is being installed along the 188 kilometre distance between Tilbury and London, Ontario. There has been recent controversy whether the HTCMB is a suitable replacement to the typical, concrete barrier that exists through most of the length of Highway 401. The Ontario government as indicated its intention install the concrete barrier at a later date and the HTCMB installation was identified as a temporary, quick solution.
The Ontario Provincial Police (OPP) released a photo of the tanker truck at its final rest position and this is shown below. We have attached three red circles to highlight points of interest.
OPP photo with red circles highlighting points of interest.
The view shown above is of the truck pointing westward at the north edge of the eastbound median lane. The Downie Road overpass is located just a short distance behind the camera. It can be seen that the left side wheels of the truck are stopped within the eastbound median lane of the highway. For all meaningful discussion this truck passed through the median and into the travel path of eastbound vehicles.
The red circle at the upper right of the photo is there to indicate that the truck passed through the barrier some distance to the east of its final rest position. We cannot use the rest position as an indicator of whether the truck entered further into the eastbound median lane. This conclusion must be made based on what evidence is shown in the vicinity of the red circle in the background. The OPP did not release a photo showing that evidence. It would be expected that this truck would have reached a maximum displacement into the median lane some distance behind its rest position. Thus this single photo is deceiving with respect to the important issue of how far the truck travelled into this opposing lane.
The red circle at the left end of the front bumper illustrates that there is direct damage at this location which is below the level of the three cable wires that are pressing against the left side of the truck. The photo below shows a typical example of the HTCMB located about 20 kilometres west of the Downie site.
View of the HTCMB installed near Kennesserie Road just east of Chatham, Ontario.
It can be seen that the barrier contains four cables. Three of those cables are pressing against the left side of the tanker truck and therefore one of the cables is not visible. A closer view of the red circle at the extreme bottom left of the OPP photo suggests that the fourth cable may be visible here .This cable would have been the bottom one and the truck would appear to have driven over top of that cable.
The damage to the left edge of the truck’s front bumper would therefore be consistent with contact of that bottom cable. The news media reported that the reason why the truck crossed into the median was because there was a deflation of the left front tire of the truck. While that may be possible the bottom cable would also have been pressing against that tire and could very likely have caused the tire damage after the truck had already crossed the median and struck the cable barrier.
It was reported that no injuries occurred as a result of this incident and that there was no impact with opposing eastbound traffic. That is fortunate. However the result could have been much worse. If the eastbound traffic was sufficiently dense at the time that the truck entered partly into the eastbound median lane an eastbound vehicle occupying that lane could have collided with the truck. Even if a collision was avoided the driver of such an eastbound vehicle might have been forced to steer quickly and hard. Such an action could easily cause a collision with other eastbound traffic. The consequences could have been unpredictable.
Passing through the site in the morning and evening of December 19th it was observed that the HTCMB was still not repaired. The photo below is frame taken from video of our westbound vehicle and the tire marks from the tanker truck can be seen in the grass median.
Frame from video taken from a westbound vehicle on December 19, 2018 showing the tire marks of the truck in the median.
This view shows that the cables are all loose, likely in preparation to repair the system. Another frame from the video (below) is closer to Downie Road and shows a further indication of the loose cables.
View of the loose cables on the struck cable barrier at the Downie Road overpass.
Our observations were that the cables were loose for several kilometres to the east of the incident. This observation has to be of concern. On the third day after the collision the cable system remains inoperative. What if another vehicle travelled into the median anywhere along that distance of several kilometres before the repair was made? Not only would the system fail to arrest that vehicle but the striking of the loose cables could cause an unpredictable interaction with the striking vehicle that may cause more harm than without its presence. In contrast, if a concrete barrier was present there is no doubt that the truck impact would not require repairs to that barrier.
As an independent, accident reconstruction and road safety business, Gorski Consulting has no special interest in the documenting of these incidents along Highway 401. Up to the present time we have not be retained by any involved party, municipality or the Ontario Ministry of Transportation to support or condemn the actions of any individual or organization. As a result our comments are completely free any special interest. While the future remains to be seen there are concerns that are beginning to reveal themselves of about the functioning of the HTCMB being installed along Highway 401 between Tilbury and London.
Most importantly it needs to be stressed that the OPP need to be involved in providing a detailed and unbiased documenting of those incidents where the HTCBM has been struck. While a single photo such at the one provided by the OPP can be helpful, it can also be deceiving. When evidence crucial to the understanding of the occurrences is not released the public develops a mislead understanding of these important events. If the documenting of these incidents is beyond the capability of the OPP another independent agency needs to become involved to make this information available to the general public.
Impact of Stopped Truck In Hwy 401 Construction Zone
Why was a transport truck stopped on the westbound Highway 401 in a construction zone near the James Snow Parkway near Milton Ontario when it was rear-ended by a mini van resulting in major injuries to the two occupants of the the van?
The official news media provided their information about the collision which was from paramedics at the site as well as from “reports from the scene”. At no point was there any indication that investigating police provided any information to them.
A twitter post by Sgt Kelly Schmidt of the OPP provided photos of the two vehicles. The only comment made by Sgt Schmidt was that a “mini van drove into a construction zone and collided with a parked construction vehicle”. But there was no additional information. Below is a photo of the rear of the truck that was submitted by Sgt Schmidt.
Why was this construction truck stopped at a location where it was rear-ended on Highway 401?
Photos of the van from Sgt Schmidt’s posting are shown below.
A photo from local news media provided the additional photo below.
In the above photo one can see at the left of the view that the portable concrete barrier comes to an end. Were the units of the portable barrier being removed or loaded onto the trailer of this truck at the time of the crash? Is that why it was stopped near the end of the barrier? If the barrier is located to the right of the van then one would think that the travel lanes designated for public travel would be located to the left of the van. So one would think that the van was moving correctly in a travel lane designated from highway traffic. But why would a construction truck be “parked” in a travel lane?
The procedure of off-loading or loading such portable barriers from a lat bed trailer is shown in the photos below taken from a construction zone located on Highway 401 near Chatham, Ontario.
View looking westbound on Highway 401 on November 23, 2018 showing how the parts of a concrete barrier are being loaded onto a flat bed trailer.
Note that the crane that is lifting the portable barrier units and the flat bed trailer are positioned safely behind the existing barrier. There is no opportunity for any traffic to strike these vehicles when they are safely behind the barrier. So how is it that the truck in the collision was not located behind the safety of the barrier? Or was it? It was reported that this collision occurred at approximately 0130 hours. In this darkness it might be very difficult to detect a stopped truck in such a construction zone as it would not be expected.Clearly there is some confusion here that needs clarification. Why is it that neither the police nor the official news media can not provide such basic information so that the public can understand how and why this collision occurred?
Addendum
The proper procedures to be used to close the lane of a highway for construction purposes is well laid out in Book 7 Temporary Conditions of the Ontario Traffic Manual.
Lane closure procedure as illustrated in Book 7 Temporary Conditions of the Ontario Traffic Manual
The use of a Sign Truck and a Crash Truck each equipped with TC-12 Flashing Arrow Signs, if positioned corrected would make it extremely difficult for a vehicle to maneuver around them in such a way as to strike a “parked” truck as described in Sgt Schmidt’s Twitter comment.
Highway 401 Safety Issues – Gaps Between Vehicles
The results have now been tabulated with respect to the gaps between westbound vehicles travelling in the right lane of Highway 401 from four videotaping sessions. It can be recalled from previous discussions that Gorski Consulting has conducted videotaping at four sites along Highway 401 in South-western Ontario, as indicated in the figure below.
Location of testing sites along Highway 401 where traffic observations were made.
The videotaping at Elgin Road was conducted in November, 2016 and is not included in the calculations. A second videotaping session was conducted at the Westminster Drive site. Thus we have results from four taping sessions at three sites.
For the present time only about 15 minutes of videotape was examined from each session. Examining all of the video would have taken more effort than could be accomplished in this non-funded research. The results shown in the table below may appear complicated and we will provide some explanation.
As indicated in the upper part of the table, the total numbers of westbound vehicles observed in each of the four videotaping sessions in shown in the upper part of the table as well as a separation between heavy trucks and non-trucks. Medium-sized trucks was included in the “non-truck” category so that we could focus on the involvement of large, air-brake-equipped vehicles from the rest. There were only a couple such medium-sized trucks in each sample so there was not a large part of the sample.
This data only looks at the traffic in the right lane of the highway. There were vehicles travelling the passing, or median lane that are not being considered. To standardize the procedures, a vehicle was counted to be in the right lane when, upon passing the 400-metre-marker, the vehicle was observed to be in the right lane. Vehicles that we in the passing/median lane at the 400-metre-marker that changed lanes into the right lane were excluded from this analysis. Vehicles that were in the right lane at the 400-metre-marker that changed lanes afterward into the passing lane were included in the data. There were not a large number of vehicles that performed these lane changes in the 400 metres of observation.
It can be seen at the right of the upper part of the table that the “Percent Trucks” values vary substantially from one session to the next. This is because we purposely selected days when the percentage of trucks would likely be different. So the “Westminster Drive Oct 30” and the “Graham Road” were conducted on typical weekdays when percentages of heavy truck traffic would be expected to be high. In contrast the “Westminster Drive Dec 2” session was on a Sunday when truck traffic would be low. Also, the “Dillon Road” session was obtained on the Friday after the American Thanksgiving Day holiday when truck drivers would be expected to stay at home for the holiday and therefore the truck traffic was low. This facts need to be kept in mind when drawing conclusions from the data.
In the bottom part of the table we show the results from the actual gaps that were observed in traffic. The gaps were noted by using one of our markers (usually the Zero marker) that was placed on the roadside next to a video camera. The timecode was documented when the front end of a vehicle passed the marker and then a second timecode was documented when the rear-end of the vehicle passed the marker. The same was done for the next approaching vehicle. Then the elapsed time was noted from the rear of the first vehicle to the front of the following vehicle. This is the time gap.
The “Average Time Gap For All Vehicles” is the value of the time gap between individual, westbound vehicles divided by the total number of vehicles observed in the westbound right lane. To some degree this is a measure of the density of traffic in the right lane.
We purposely focused on those vehicles that were following closely behind a leading vehicle. This can be considered to be unsafe because it may provide insufficient time to react to changing traffic conditions such as sudden slowing or stopping of traffic. The presence of large heavy trucks is a problem because they require a longer stopping distance but also because their large width and height makes it difficult for drivers following them to see the roadway ahead. We selected those observations where the time gap was 2.0 seconds or less and this is what is shown in the table.
As an example using the “Westminster Drive Oct 30th” data, of the 91 trucks that were observed in the right lane, 19 of those trucks were observed to be following a vehicle ahead by 2 seconds or less. Of the 46 “Non-Trucks”, 11 of those were observed to be following at 2 seconds or less. Thus, in terms of percentage, 20.9 percent of trucks were following a 2 seconds or less and 23.9 percent of non-trucks was following at 2 seconds or less. These percentages are shown for all four sessions below:
Westminster Drive Oct 30th: Trucks =20.9, Non-trucks= 23.9
Westminster Drive Dec 2nd: Trucks=14.1, Non-trucks=24.2
Graham Road: Trucks=15.9, Non-trucks=20.8
Dillon Road: Trucks=4.8, Non-trucks=16.2
We can also take all four sessions as a whole and indicate that of the 260 observations of heavy trucks 40, or 15.4 percent were observed to be following a vehicle at 2 seconds or less. For the 272 observations of non-trucks, 58, or 21.3 percent were observed to be following a vehicle at 2 seconds or less.
We can also examine what kind of vehicles were being followed close behind, as shown in the table below. This data is separated into the individual sessions as well as summarized for all four sessions combined.
Although the numbers are small they suggest that the most common combination of one vehicle following less than 2 seconds behind another is where a non-truck is being followed by another non-truck. The least common is where a heavy truck is following a non-truck. These results may be surprising considering the comments made by various drivers of passenger cars and light trucks claiming that aggressive truck drivers attempt to drive them off the road by their close tail-gating. These preliminary data may suggest that it is more common that the drivers of passenger cars and light trucks and van are the ones who do more tail-gating than the drivers of heavy trucks. However the small numbers of observations in this study make these judgments non-conclusive. Exploration of the full 2 hours of videotape from each session might help to solidify what is the actual case.
Highway 401 Safety Issues – Average Speed
Observations of average speeds of vehicles travelling along Highway 401 have been updated as a result of further analysis of the videotape obtained from four sites. It can be recalled from previous postings that Gorski Consulting has conducted videotaped observations of traffic at four sites along Highway 401 as shown in the figure below.
Location of testing sites along Highway 401 where traffic observations were made.
Analysis of the second testing at the Westminster Drive site on December 2, 2018 has just been completed resulting in the updated results shown below.
It is interesting how the presence of heavy trucks in the median lane would appear to reduce the average speed of all vehicles in that lane. That should not be surprising as truck speeds are limited to 105 km/h. From a safety perspective the issue is how the lowering of average speed in this manner can provide a safer environment when this creates more conflicts between vehicles travelling at substantially different speeds.
It is not our purpose to engage in this discussion at this time. The purpose of presenting this data is to provide some broad indicators of the content of the videotapes. Additional data will be reported in the near future. Once some of these broad indicators are presented it is hoped that more detailed studies of the content will be presented and discussed.
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