In the Steveston Village area of Richmond, at the intersection of Number 1 Road and Moncton Street, in early December 2011 we saw the return to British Columbia of a pedestrian road crossing system long considered obsolete - called “the pedestrian scramble.”

The concept is that briefly, an intersection otherwise busy with vehicular traffic, is closed to vehicles from all directions, leaving an open square across which pedestrians can move in all directions.  The modern version of this system includes parallel and diagonal white lines to guide pedestrians in their trip across the intersection, from any corner to any corner.  A synthesized voice command broadcast at considerable volume further guides and controls the movement of pedestrians, with a message such as “the walk sign is on for all crossings.”

In the early 1950’s Vancouver had a scramble intersections along Granville Street at Georgia Street, and again at Hastings Street.  The reasons for the abandonment of the concept, in favour of the now conventional corner to corner, 90 degree change cycle, may be lost in the mists of time.  Factors of efficiency or safety must have caused the concept to be discarded for several decades.

The term “pedestrian scramble phasing” is perhaps an antique legacy from the early attempts at this type of traffic engineering.  One Road Rules reader has also mentioned that term used long ago in Vancouver was “scatter lights.”  “Scramble” and “scatter” are words the may suggest anxiety, urgency or even danger.  Some traffic experts have preferred that terms “pedestrian priority phasing” and “pedestrian criss-cross,” the latter term emphasising the diagonal advantages under this regime.  However, for the moment, “scramble” has a lot of currency.

Although Richmond has taking a pioneering step in this regard, at least two other cities in Canada have implemented pedestrian scramble phasing.  Toronto reportedly has three major downtown intersections governed by this technology, and Calgary has at least two such crossings.

Pedestrian scramble phasing differs from city to city, but falls into three main categories.  “Type A” allows pedestrians movement in all directions, when the intersection is closed to vehicles.  “Type B” allows “parallel to roadway crossings, but no diagonal movement.”  “Type C” is a hybrid, which combines “Type A” movement with the pedestrian’s right to also cross concurrently with parallel vehicular traffic, upon a green light.

The cost of upgrading an intersection to pedestrian scramble standards is substantial.  Reportedly, the very elegant and beautifully paved Richmond edition costs around $600,000.

This leads to the obvious question, “what are the benefits?”  From the Toronto standpoint, the condition or combinations of conditions that may support this kind of expense are:

1. Regular pedestrian volumes of over 3,000 pedestrians per hour for eight hour periods.
2. Regular pedestrian volumes of over 2,000 pedestrians per hour for eight hour periods, combined with high turning vehicle volumes.
3. Intersections with a history of a large number of pedestrian-vehicle collisions.
4. A demonstrated need for a high volume of pedestrians to cross diagonally.
5. Unusual intersection geometry, leading to safety concerns.