An Incremental Approach to Protected Intersections for Cycling

By Darren Proulx

Protected cycling infrastructure is catching on across North America as cities become aware of the economic, health, social and spatial benefits of cycling. In 2015, Calgary opened a network of protected intersections all at once. In 2016, Vancouver is in the process of opening five new protected cycling lanes in the downtown.

Vancouver Carrall unprotected intersection cycling
The Carrall Street protected bike lane in Vancouver is not protected at the intersection where it is needed the most .

Now that protected cycling lanes are full steam ahead in many cities, many are turning their attention to intersections. Based on the cycling safety report from the City of Vancouver, between 48-74% of vehicle collisions with people cycling (based on the type of street and cycling infrastructure) occur at the intersection (as opposed to mid-block). However the debate around protected intersections is mixed. Many in the cycling industry are focused on building complete dutch-style protected intersection, no exceptions. We must not let perfection become the enemy of great.

Cycling Stats - Vancouver Cycling Safety Study 2015
A study by the City of Vancouver demonstrates that the majority of cycling collisions occur at the intersection.

While many engineers would like to implement fully protected intersection, their hands are often tied by the requirement to accommodate the large turning radii of emergency vehicles and semi-trailer trucks that deliver many of our daily goods and needs.

Chicago turning radii image
Chicago street design guide showing the wide turning requirements for large vehicles. (City of Chicago)

Most fully protected intersections, while successful are also quite large. Take the Burrard – Cornwall intersection in Vancouver or the Salt Lake City protected intersection. With a 27-31 meter width, most intersections in older inner city neighbourhoods do not have this space. Moreover, this isn’t particularly friendly for walking since this forces long crossing distances.

Canada risk chart
Risk of fatalities in Canada

One alternative solution would be to ban larger vehicles, which would have an impact on deliveries and important emergency services. The city of Calgary council started a very important conversation around risk mitigation. In Canada there is a 13 times more likely chance that you will die from an automobile collision than are a fire.  Are we focusing our efforts in the right area by making our roads wider to accommodate the large turning radii of fire trucks which also induces speeding?

Ideally in the future, cities would enact policies that require transport vehicles to use regional distribution hubs on the edge of cities to transfer shipments to smaller vehicles or cargo bikes for the last mile.  The cost savings of such a policy would be significant. This would reduce the damage large vehicles do to our streets, reduce delivery restrictions and improve on demand delivery performance due to the smaller vehicle size. Removing large trucks off of our roads would also significantly improve safety for walking and cycling, as it estimated that 19% of cycling collisions occur with large trucks.

Unfortunately we have to get creative until we can sort out how to restrict the use of large delivery trucks and emergency services vehicles on our streets through different procurement practices, safety requirements and policies. Fortunately we already have the solution, we just have to look to Vancouver. Vancouver has been taking a more pragmatic approach to protected intersections. Due to space limitations, it may not be possible to protect the entire intersection at the time. However it may be possible to provide protection for the dominant directions of walking and cycling travel.

Denman and comox Vancouver protected cycling intersection
This partially protected intersection at Denman and Comox in Vancouver uses concrete islands and phased traffic light signalling to restrict vehicle movement in the dominant direction of travel.

Vancouver has many examples of this including the intersection at Dunsmuir and Hornby Street, the intersection at Denman and Comox Street, the intersection at Main and Union Street. In all of these cases, the city strategically used a mixture of concrete barriers and phased traffic signals. As a side benefit any improvements for cycling also assist people walking by reducing the crossing distance they must mix with traffic.

Fully protected intersections are definitely the gold standard, however if we give ourselves some leeway in how we define a protected intersection we can achieve results now rather than later. Instead of waiting for costly, complicated large scale redesigns, incremental changes can be installed now providing protection for the dominant cycling movements. As cycling volumes increase or large vehicle restrictions are eventually introduced the intersection’s protection can eventually be improved.

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