Pedestrian Safety Guide and Countermeasure Selection System

 

Case Study No. 34

Staggered Median

Tucson, Arizona

Prepared by Laurie Actman, Patrick McMahon, and Henry Renski, University of North Carolina Highway Safety Research Center.

Problem

A five-lane urban arterial with heavy traffic created difficult crossing conditions for high school students. Moreover, student crossing behavior was varied and erratic, and a number of minor collisions involving students and motorists had occurred. Student use of a nearby intersection crosswalk was neither the norm nor in a direct line between the school and a desired destination and transit stop across the street.

Background

Staggered median with HAWK beacon at bus stop.

Twelfth Avenue is a four-lane arterial with a center two-way left-turn lane that carried approximately 19,500 vehicles per day with a posted speed limit of 35 m/h. Over 220 pedestrians per day cross nearby, but not necessarily at the intersection of 12th Avenue and Veterans Boulevard. The side of Pueblo High School closest to 12th Avenue contains one of the school's major pedestrian exits as well as student pick-up and drop-off areas. A restaurant was located across the roadway from the school and a transit stop, which attracts a large number of students before and after school.

In the years prior to installation of the improvement, conflicts between pedestrians and motorists became a significant problem. Several minor collisions involving students and motorists had occurred, along with other instances of vehicles quickly braking for students in the roadway. The area was also aggravating for 12th Avenue drivers, because students would often meander or stop in the roadway, delaying traffic in both directions for a significant amount of time. School officials were concerned that this situation would eventually lead to serious confrontations between students and aggravated drivers.

Solution

Design drawing of staggered median and split crosswalks.

The City Traffic Engineering Department worked closely with the school administrators and the school transportation committee to analyze the problems and develop alternatives.

In order to address the diverse issues, the existing crosswalk between the high school and the restaurant was removed and replaced by a split crosswalk, each leg approximately 24.5 m (80 ft) from the other. The sections of the split crosswalk were connected by a fenced pedestrian refuge median, installed in the center two-way left-turn lane. At one end of the island, the fence opens to the crosswalk connecting to the high school exit. At the other end, the fence opens onto the second leg of the crosswalk, which connects to a transit stop waiting area, just south of the restaurant parking area. The fence itself works successfully as a channeling barrier. Because the crosswalk is staggered, crossing pedestrians are forced to look at oncoming traffic while walking down the fenced median.

Close-up of fenced pedestrian refuge median.

Each stage of the crossing is equipped with a pedestrian hybrid beacon to assist pedestrians in crossing the street. The crossing is clearly marked in both directions, and he pedestrian hybrid beacon responds quickly to pedestrian activations. Because of the staggered median island, traffic is halted on only one half of the roadway when the flashers are activated. The City and school district split the cost of the project, and the material used by the City to construct the median fence replicates a fence that surrounds the school.

Results

The split crosswalk successfully addresses several of the site's previous problems. Most importantly, it gives pedestrians a safe haven from automobiles in the road's center and forces pedestrians to look at oncoming traffic while crossing. It also helps to minimize the number of students meandering back and forth across the street, giving them a place to socialize in the fenced median, rather than in the street. Unfortunately, because the fence is the only median constructed on this straight five-lane road, a few drivers who were not paying attention have run into the fence at the end of the median. Despite this problem, the Council Member from this district and Pueblo High School administrators are very pleased with the result.

Contact

Diahn Swartz, P.E.
Traffic Engineering Manager
City of Tucson
201 North Stone 5th Floor
Tucson AZ 85701
Phone: (520) 791-4259