Exclusive Pedestrian Phasing
Beverly Hills, California
Information provided by Bijan Vaziri, City of Beverly Hills.
Beverly Hills, California
Information provided by Bijan Vaziri, City of Beverly Hills.
A high number of conflicts between pedestrian and vehicles were occurring at busy downtown intersections.
With exclusive pedestrian signal phases, diagonal crossings are allowed as well as conventional crossings.
The residential population of Beverly Hills is about 35,000. However, the daytime population is estimated at about 170,000, mostly concentrated in the Business District, which is informally called the "Business Triangle." Daytime pedestrian activity is very heavy in the Business District due to the concentration of businesses and services and the high volume of tourists visiting the area around famous Rodeo Drive. The primary concern for the City was the high number of conflicts between pedestrians and vehicles at many of the intersections, especially during holidays and tourist seasons. Large pedestrian flows were blocking crosswalks to turning traffic during the entire green signal phase. A review of the collision history revealed several reported vehicle-pedestrian collisions and data collectors observed numerous "close calls."
Two pedestrians cross diagonally during the exclusive pedestrian phase
Staff analysis indicated that if no pedestrians were in the intersection during the vehicular signal phase, traffic would flow more smoothly. The addition of an exclusive pedestrian signal phase to the signal timing was considered to clear the intersection of pedestrians during the vehicular phase, allowing better movement of vehicles and permitting pedestrians to cross without vehicle interference. This would improve the safety of pedestrians and reduce the potential for auto/pedestrian conflicts and collisions. At the time of implementation, very few jurisdictions were known to have this type of signal operation.
In 1987, the City of Beverly Hills modified traffic signals at eight intersections within the Business Triangle to include an exclusive pedestrian phase where all approaches would stop to let pedestrians cross the intersection either diagonally or conventionally. The intersections included:
With exclusive pedestrian phases in place, pedestrians were allowed to cross diagonally as well as conventionally. In that case, the longer diagonal pedestrian path was used to determine the optimal clearance time for that signal phase. A range of 20-22 seconds of total pedestrian signal phase was determined to be appropriate. At the time, all Business Triangle signals were operating on 50-second cycles, and the introduction of the pedestrian phase increased the cycle to 60 seconds to clear vehicles through the intersections.
Pavement markings were added to indicate that diagonal crossing was permitted at each of the intersections, and special "diagonal crossing OK" signs were added to each corner. For better visibility, pedestrian signal heads were added to face the diagonals of the intersection so they could be seen for diagonal crossings.
The average cost per intersection was very low compared to other improvements, under $1000 per signal.
During the planning of this project, there was a concern that an exclusive pedestrian phase would be confusing for both motorists and pedestrians. After implementation, it seemed that people quickly became accustomed to the new operation. Public opinion has been very favorable, and other communities have contacted the City seeking information to install similar operations.
A capacity analysis was conducted as part of the evaluation of the new signal operation. Using the "ICU" method, a level of service (LOS) was calculated before and after the implementation of the exclusive pedestrian phase. The following table shows the summary of the LOS calculations.
|Intersection||Pre-Treatment LOS||Post-Treatment LOS|
|Brighton / Canon||.40 A||.63 B|
|Brighton / Beverly||.69 B||.92 E|
|Brighton / Rodeo||.48 A||.71 C|
|Brighton / Camden||.40 A||.66 B|
|Brighton / Bedford||.34 A||.57 A|
|Dayton / Canon||.31 A||.54 A|
|Dayton / Beverly||.55 A||.81 D|
|Dayton / Rodeo||.34 A||.57 A|
The analysis indicated that for most intersections, the change in LOS would be within an acceptable range. However, for two intersections, Brighton/Beverly and Dayton/Beverly, the LOS would be dropping to unacceptable levels (LOS E and D respectively). City staff had concerns about the successful operation of these two intersections. Staff noted that implementation was very successful at the other six intersections, and the aforementioned two experienced an increase in delays on Beverly Drive, which is the major north-south street through the Business District. This analysis resulted in the removal of the pedestrian signal at these two intersections. The remaining six continue to be operational as of 2012.
Since the primary objective of this project was to improve safety, detailed evaluation of collisions of all eight intersections was conducted. Collision data from 10 years before the implementation and 10 years after the implementation were used for comparison. The primary focus was to examine the auto/pedestrian type collisions before and after the implementation of the project. The following table shows the average change in collisions over the comparison periods.
|Intersections||Number of collisions before||Percent of total collisions before||Number of collisions after||Percent of total collisions after|
The table indicates a reduction in auto/pedestrian collisions by as much as 63% for the six intersections that maintained the pedestrian phase. Data have suggested unequivocally that this project was a success. Further, overall collision in the Business Triangle were reduced by 20%. However, at those two intersections where the pedestrian phase was eliminated (Brighton/ Beverly and Dayton/Beverly), auto/pedestrian collision rates remained unchanged.
Based on experiences gained from implementation of such a project in Beverly Hills, the following checklist is recommended to help to evaluate the need for installation of exclusive pedestrian phase at an intersection. These are some of the issues that need to be considered in selection of intersections for placement of an exclusive pedestrian phase. However, additional research on this issue is needed.
A: Total pedestrian crossings volume should be high (preferably, more than 1000 pedestrians per hour) during at least four hours a day. The operation would not be efficient if it is based on high volume of pedestrians during only one hour of a peak period.
B: Vehicular volumes shall be moderate and steady for many hours of the day with high percentage of left or right turns. Intersections with extreme peak hour conditions (a.m. and p.m. peaks) may not be able to handle traffic demand and may cause delays during the pedestrian phase. It is important that vehicular peak periods coincide with pedestrian peaks. Recommended total intersection approach volume is to be less than 2000 vehicle per total approaches per hour.
C: It is recommended that the existing level of service capacity for selected intersections be at level "C" or lower.
D: The longer diagonal path must be used to establish the timing for pedestrian clearance (Flashing Don't Walk). Therefore, smaller intersections require less time for exclusive pedestrian phase, thereby reducing vehicular delays. Recommended area inside the crosswalks is 40 ft for minor streets and 40 to 60 ft for major streets.
E: Caution is recommended in selecting intersections for an exclusive pedestrian phase where both streets are two ways and/or left turn or right turn phasing is used.
F: Selected intersections shall be well illuminated to ensure that pedestrian diagonal crossings are clearly visible by the motorists during dark hours.
G: The position of pedestrian heads will need to be adjusted so pedestrians wishing to cross diagonally can see the indications. Preferably, additional pedestrian heads would be installed to accommodate diagonal crossings.
In general, exclusive pedestrian phase is a low cost, effective tool to improve safety and reduce the potential for automobile and pedestrian conflicts. There is no national or state "warrant" system for justification of exclusive pedestrian phase on signalized intersections. Therefore, each jurisdiction will need to practice what is best to maintain safety while keeping traffic operation as efficient as possible.
Bijan Vaziri P.E.
City of Beverly Hills
455 N. Rexford
Beverly Hills, CA 90210
Phone: (310) 285-2504
Vaziri, Bijan. "Exclusive Pedestrian Phase for the Business District Signals in Beverly Hills, 10 Years Later: City of Beverly Hills, California, 1996."