Set-up of a collision rapid notification system for emergency expressway closures is needed to deal with instances where a collision leads to additional collisions. The need becomes obvious from examination of many expressway, multi-vehicle pile-up collisions.

As a recent example, a fatal, multi-vehicle pile-up occurred in the westbound lanes of Highway 401 at Foldens Road, near Ingersoll, Ontario, on the afternoon of February 13, 2019. Following the original crash at Foldens Road, two additional, multi-vehicle collisions occurred to the east of that site. One of the subsequent collisions occurred near the On-Route service centre is just east of Foldens Road. Another subsequent collision occurred east of Sweaburg Road. The distance between Foldens Road and Sweaburg Road is about 7.5 kilometres and this provided some indication of the possible length in the backup of traffic that occurred as a result of the original collision.

Site of the fatal, multi-vehicle pile-up in the westbound lanes of Highway 401 near Foldens Road near Ingersoll, Ontario. (Courtesy OPP Twitter)

The latest counts indicate that traffic volume approaches about 70,000 (AADT) in this vicinity of Highway 401 which is equipped with three-lanes in each direction. About half of the weekday traffic is composed of heavy trucks. It is not difficult to comprehend that a stoppage in traffic can quickly build several kilometres behind an initial collision site.

The problem is that sudden traffic stops from collisions are unexpected. There is no signage to warn of the upcoming stoppage. In contrast, when a stoppage is the result of road construction and maintenance signs are posted for several kilometres before reaching the actual construction site. This signage is often insufficient when a stoppage occurred further behind the commencement of the signage. Yet, some benefit is achieved in comparison to the emergency stoppage from an unexpected collision. Thus it is this sudden and unexpected stoppage of traffic, often in poor weather, with poor surface and visibility conditions, that is the problem that needs to be addressed.

The problem is that when a collision occurs the responders who are the first to arrive are not equipped to deal with the traffic stoppage. Those responders are there to deal with the immediate emergency of securing the lives of those injured in a crash. Although the vehicles of those responders may be equipped with sirens and emergency lighting that equipment is often of limited use. The typical height of a police cruiser or ambulance is well below the height of the typical tractor-trailer. So when a large number of tractor trailers come to stop close to each other a tall wall is created which can block most of the view of any emergency vehicles.

Large blocking or crash trucks with TC-12 arrow signs are often positioned at lane closures when sufficient time is available. But such arrangements are often much too slow to deal with the sudden stoppages that occur from unexpected collisions. The question becomes whether a system can be set up to respond with such blocking or crash trucks at an earlier time. This question should be posed particularly in those times and locations when collisions are more likely to occur. So for examine, the approach of a winter storm is likely to generate road surface and visibility deterioration which is likely to lead to crashes. So can such blocking and crash trucks be in a state of alert, much like firemen waiting for an alarm? Can more notification systems be set up along busy expressways such as Highway 401 that can display warnings such as “Stopped Traffic Ahead”? These are the types of considerations that need to be discussed to minimize the probability of additional collisions when vehicles come to be stopped for an initial collision.

Furthermore, Automatic Emergency Braking (AEB) is greatly needed at this time. Governments should do whatever they can to speed up the installation of this technology. AEB, if reliable, can do much to reduce collisions due to stopped traffic on expressways.