Green wave Raadhuisstraat - Amsterdam, The Netherlands

Great video describing a green wave for cyclists in Amsterdam.

Combined with the simulation it shows how people on bicycles can be given priority and how signal timing analysis and simulation can represent the real world.

Bicycle Countdown Signal - Time to Green

The bicycle signal countdown timer in Amsterdam, a video can be found here and one in Delft here.

The following is an example of a Countdown to green indication for a bicycle signal in Amsterdam.

The exact time is not provided, but a Wacht message with the circular display that reduces the number of LEDs.

This is similar to the Japanese (sand in the hour glass concept). My host told me that studies have shown that the addition of this signal head has improved compliance. It was not clear from our conversation whether the data collected was from a statistically significant sample.

After uploading this I found a blog post or two about these installations.

In particular, the blog highlights two important concepts from the Dutch designs:
"Traffic light cycle times for cyclists are short. This leads to a low average delay for cyclists at these points, often lower than the average delay for drivers. This increases the competitive advantage of bikes over cars.

Permeability for cyclists. In both cases in these videos, we're crossing in a direction where motorists can't also drive, meaning that cyclists get more direct routes. Again, a competitive advantage for bikes over cars."

This is the one from Amsterdam.

Bicycle and Pedestrian Indications

Here's another example of a traffic signal for peds and bikes. I learned yesterday that the reason they show a yield sign on the bike signal pole is in case the signal fails it reinforces the control at the intersection is to be yield, similar to our red flash intersection and the instructions that you must stop at a traffic signal that is dark. Several notable things here.

The intersection of Amstelveenseweg and Theophile de Bockstraat

  There are pedestrian indications on every single slice of concrete at the intersection. In reality, this is a four stage crossing for pedestrians with a crossing of the bicycle traffic (what would be right turning traffic in the U.S. (on the right of the picture), the traffic coming from the left (just after the yield and bicycle indication), the through traffic and the right turning traffic on the other side. There is a push button detector for cyclists for that second ped crossing.

Leading Bicycle Interval

We arrived in Amsterdam and the first thing I did upon arriving is visit the closest traffic signal to our hotel. I was interested to compare the experiences in Denmark with the Dutch practices. This was a minor street connecting with a more significant street adjacent to the Rijksmuseum. The first thing noticeable about this signal was that the indications for the bicycle are nearside. The second is that there are two separate indications (a large head mounted at around 3 meters) and a 10 cm (4 inches) indication. My guess is that the redundant signal head is used for the same reason we use multiple displays, but can't be sure. The third and most interesting from an operations perspective is the leading bicycle interval. I tried to take as many pictures as I could one after another to guess at how much time the intervals was for the bikes (it was about five seconds based on my camera time stamp). It seems that the reason for a Leading Bicycle Interval (LBI) is that the crosswalk is very large and it would be a nice thing to allow people on bicycles to establish themselves in the intersection across the crosswalk and to make the turn if they were so inclined. This might reduce the potential conflict point at the intersections which you can see just past the crosswalk and out of the shade of the curb tight building. The fourth application which we have used very sparingly in the U.S. is mirrors. In this application, I am guessing it helps freight and other motor vehicles determine if there are pedestrians coming up along the sidewalk and bikes approaching. It's another cue for encouraging the safe movement of traffic. I can already hear the complaints of maintenance staff if we proposed these at intersections.

Assuming that a community only wants to spend so much for a traffic signal (I doubt the Dutch love their signals any more than we do), in the U.S. (and in Portland), I would like to do an assessment of what elements of traffic signals cost us the most money (foundations for signal poles and the mast arm signal poles themselves) and what yields the highest safety benefits. There are distinct costs for traffic signals that require to be mounted over the lane lines and that is a function of the assumed speed of traffic and reaction times and so many human factors issues that it would be very helpful to know the tradeoffs between actually safety elements we design at intersections and their cost. I would be willing to wager a strong cup of coffee at Water Avenue that we could save ourselves a lot of money if we traded the costs of foundations and invested in better detection, marking on the pavement, and maintenance resources.