Portland Traffic Signal Challenges

The google machine is pretty impressive. I entered "Portland Traffic Signal" and quickly found this video. Please note that this isn't our standard clearance interval duration for the City. Lucky for the City, we have effective maintenance staff that are very good at responding to infrastructure failures such as this.

Designing Cities: National Association of City Transportation Officials (NACTO) Conference

I have been fortunate to be asked to speak at this conference in New York City. The NYC Department of Transportation has done some impressive things to remake the streets; reclaiming them from people driving through the communities where people live, work, and play. Part of the reclamation is considering the needs of people on bicycles and pedestrians more holistically and there some great sessions on this topic today. 

The session where I presented was on Traffic Signals: Integrating Time & Space. We had four great speakers (Ryan Russo, NYCDOT, Jamie Parks, City of Oakland, Jeffrey Rosenblum, Cambridge, MA & myself). Ryan started out with some high level applications and mentioned that is is "just as important to think about signal timing as it is the geometry (pretty heady stuff from a planner). He cited the issues of a turn lane being on the "wrong side" (left side bike on left side of left turn lane) of a bike lane is illegal in MUTCD. He also described one of the elements they strive for us a 60-second cycle length combined with a double cycle length. They also use gating (he called it feathering to reduce the traffic hitting the bottleneck, arriving early). Good strategies that engineers have forgotten over time because we think a lot about actuated control and how it should work. 

Finally, he gave examples of leading pedestrian intervals, split LPIs where they hold just the turning movement red (exclusive turn signal movements only) and split phasing for the intersection. 

An example of a left side bike lane with a bike box for
right turns to cross in front of vehicle traffic.

NYC has creatively reclaimed public space from the auto by using
bollards (plastic wands, cones, etc) and potted trees/plants).
They have added paint with texture as well to provide a visual clue.

NYC Bus only often comes with red tint or paint to clearly delineate
the expectations for motorists. It worked well.  

Green bike lanes to provide clear direction for pedestrians and parking areas.

Bicycle Right Turn Lane with Advisory Bicycle Lanes

   Completing the series of posts of Dutch practice with right turn lanes is a very different application in a setting that is more rural or perhaps suburban (a vacation area) in nature. The street features advisory bike lanes which is a nice treatment where there is quite a bit of traffic. A treatment that made this particular location unique was that there were auxiliary bike lanes developed to allow people on bicycles to leave the main travelway to make their turn at a lower speed. This offered a certain level of comfort, because the turn was onto a separate path for cycling and walking that was fairly narrow at the intersection. The right turn lane may also increase the safety of the facility with the unintended consequence of potentially increasing the speeds on the main street. No data to substantiate that so I wouldn't develop Guidelines on this sort of treatment, but it is a nice option to consider when building new infrastructure.

Right Turn Fietsers Sign

 I came across this photo from my travels in the Netherlands and am not sure that I understand its meaning. I believe it indicates that cyclists are green and that motorists may be crossing the right turning cyclist path to travel on the right side of people on bikes.

The lane striping provides some clue, and it could be that cyclists are encouraged to transition to the 2-way cycletrack on the farside of the intersection which would indeed conflict with a right turning vehicle. The sign and the contrasting colors is a little hard to read and I don't know that I understood this the first time I rode through the intersection, although it was unique enough to take a picture of, but I am an outlier on these sorts of observations.

Right Turn Warning Sign - Traffic Safety for Pedestrians

The City has had some recent crash experience with a few of the bicycle boxes that were installed on approaches to intersections that feature a downhill grade. The local news station picked up the story tonight.  One approach to mitigating crashes is to apply an active warning sign like the one at NE Couch at Grand Avenue described here.  In the Netherlands, I never saw anything quite that obvious. There were the "Let Op" signs that are used somewhat frequently and then I recalled this auxiliary signal head which I believe communicates that there is a pedestrian crossing that the right turning movement either can't see and there is interest in warning of activity in the crosswalk, I am not sure, my recall of this intersection is that there was a bit of an offset, so if the pedestrian was crossing in the marked area furthest from the main road there could have been some sight distance limitations where this additional queue would have been helpful.   

The reason to share this is to consider how minimal the design is, whether it is effective or not, and given the anecdotal evidence that many Dutch drive their cars with the experience as a cyclist, perhaps these sorts of devices do not have to be as obvious.

NE Lloyd Bike Signal Markups

On the internet, there is a lot of information. Yet, I often find that engineering details on the net are very limited, so I am posting this bicycle signal markup to share with fellow practitioners that might be interested in more details. This markup shows how little that was done in this T - intersection to make the bicycle signal happen. The cost of the project was approximately $2,000 because the modifications were part of the existing design (the wiring was already in place as was an existing signal head) and it was relatively simple to make the change in the field.

Oregon ITE Meeting on Adaptive Signal Control - October 18th

OCTOBER LUNCHEON - ADAPTIVE SIGNAL CONTROL PRESENTATION & PANEL DISCUSSION

Thursday, Oct 18, 11:30-1:00
Lucky Lab NW (1945 NW Quimby, Portland)
REGISTER HERE  

The lunch comprises a presentation and panel discussion on adaptive signal control where speakers will discuss the pros & cons, impacts, and outcomes we have observed from implementation in the local area. Presenters will include representatives from the City of Portland, ODOT, City of Gresham, and Washington County. Shaun Quayle of Kittelson & Associates, Inc. will kick off the discussion with a general presentation on technologies, and will then proceed to moderate the panelists. Additional information on each of the panelists is provided below.
 
Moderator - Shaun Quayle, P.E.
Shaun is a senior engineer with Kittelson and Associates, Inc. He has over 10 years of transportation engineering experience, largely focused on signal systems, traffic operations and smarter ITS solutions. Shaun is serving as project engineer on the ODOT ITS Innovative Grant Evaluation Project, analyzing performance measures and results for the 5 adaptive/advanced corridors which are the topic of his short presentation. Shaun will moderate the panel discussion with the four Oregon agency adaptive experts.
 
Gresham - Tony Sepich
City of Gresham supervising electrician in the traffic signal industry for 27 years. Oversees maintenance and operations of east co. signals including design and timing. Maintains two SCATS corridors: 181st  and Burnside. 
 
ODOT - Tiffany Slauter
Signal Manager, ODOT Region 1 since January 2008. Graduated from the OSU Civil Engineering program in June 2007. Region 1 has just over 300 traffic signals that we operate, about 1/3 are 2070s running Voyage, 4 are 2070s with SCATS, and the rest are 170s with Wapiti. Nearly all of the 2070s are connected to TransSuite via Ethernet. Approximately 90 intersections will be converted from 170/Wapiti to 2070/Voyage in the next year. Most of the intersections are running fairly basic timing, though ODOT has 21 traffic signals in Tigard that has multiple features enabled.
 
PBOT - Peter Koonce
Division Manager for the City of Portland Bureau of Transportation's Signals, Street Lighting, & ITS Division. Prior to this appointment with the City, he worked with Kittelson & Associates, Inc. for 15 years. He has served as an adjunct professor at Portland State University for the past eight years teaching graduate level courses in transportation engineering. He has served on National ITE Committees and is the Panel Chair for the National Cooperative Highway Research Program project 3-103, which is a rewrite of the Signal Timing Manual. He is secretary of the Transportation Research Board Committee on Traffic Signal Systems and serves as chair of its Signal Timing subcommittee.
 
Washington County - Stacy Shetler
Traffic Engineering Manager with Washington County who has over 13 years experience in the transportation field. Stacy managed the installation and implementation of SCATS and InSync on corridors in Washington County. Both systems were activated in May of 2011 and he continues to oversee the operations and maintenance.

Please join us for the presentation and panel discussion!

Portland Traffic Signal Detector Confirmation Light for Bicycles - NE Martin Luther King Jr & Morris



One of the opportunities that I appreciate while working for the City of Portland is the chances we get to innovate in order to improve the transportation system. This Traffic Signal Detection Confirmation Light for Bicycles is one such innovation that was deemed "Intelligent" by BikePortland. Since we implemented this, we have made a few subtle modifications to improve on the original addition of a blue light that was wired into the detection at the traffic signal.  We added a red dot to the top of the bike stencil to clue people in that there is an association between this and the red traffic signal indication. There is a subtle blue dot next to the red paint, which is intended to remind users to look for the confirmation that they have been detected. 

The blue dot adjacent to the red indication is subtle.

The relationship between the stencil with red and the signal that is controlling the side street movement

A close up of the blue LED mounted to the signal head.

Delft Streetcar Construction - Laying Tracks on TU Delft campus

A post that shows some of the "tram" construction in Delft, Netherlands near the TU Delft campus. Just a few observations from the visit.

The base for the tracks was very minimal, similar to Portland streetcar construction.

The concrete blocks under the rails is supported with sand, hard to tell how deep here.

Depth of construction was likely limited because of the lack of heavy truck traffic. 

One more photo. During the two weeks I was there the slab was poured around the rails.

     

Bike Signal at NE Martin Luther King Jr Blvd & Lloyd

The newest bike signal (our 12^th) was activated today when we added the bike signal sign and plugged in the load switch in the traffic controller cabinet. The bike signal was a simple addition to an intersection that allows a movement to occur that was stopped without any cause. The east-west street of the intersection is two-way and the southbound movement is one-way. In this sort of a configuration, the westbound people on bicycles can be allowed to move with the eastbound movement because there is no conflict. The eastbound movement conflicts with the westbound movements because of the lane configuration, but the bike in the curb tight bike lane clearly does not.

There is an access to the Eastbank Esplanade to the west of this intersection, so the leading bicycle interval for the eastbound movement allows people on bicycles to get the jump on the vehicle movements and weave across the lanes to turn onto the sidewalk that leads to the path.

The series of photos shows the finishing touches that the Electrical Shop crew completed (mounting the bike signal sign and making sure that the signal was visible). The guide signs for CEID (Central Eastside Industrial District) and Steel Bridge were moved up the pole to make room for the bike signal.

I often get asked what a change like this costs. This one was particularly limited in its expense because the wiring was already there (we replaced an existing vehicular signal that was redundant) and the pole was placed in the exact spot needed for the display.

The length of the green time advance for the bicycle signal is dependent on the eastbound traffic. The bicycle signal westbound is active when the eastbound movement starts and continues when the eastbound vehicles start. Another way to think of this movement is that it mimics the WALK interval for pedestrians on the north crossing of the intersection. 

       

Nice coverage of the bike signal addition by BikePortland here at this link.