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Chapman Elementary School

Chapman Elementary
School Safety Project
Final Evaluation
 
Introduction
 
The Traffic Calming Program (TCP) undertook a School Safety Project (SSP) in the spring of 1997 on the streets adjacent to Chapman Elementary School. The school is bounded by Raleigh to the north, 27th Avenue to the west, Pettygrove Street to the south, and Wallace Park to the east.
 
Area Map
 
 
Project Goals
 
The general goal of a school safety project is to enhance the safety of younger pedestrians associated with the elementary school. Enhancing the pedestrian environment can be accomplished by reducing adjacent vehicle speeds or by reducing the number of pedestrian/vehicle interactions. The Chapman safety committee was particularly sensitive to the vehicle speed, especially at the crosswalk on 25th at Pettygrove.
 
The traffic committee adopted goals and objectives as follows:
 
I. Reduce vehicle speed around the school.
II. Improve crossing safety on NW 25th at Pettygrove.

Proposed Solution

The traffic committee chose the following tools to achieve the desired goals:
  1. Speed bumps on Raleigh and Pettygrove to reduce automobile speed.
  2. A pedestrian refuge island on 25th Avenue at the crosswalk at Pettygrove to increase crossing opportunities and pedestrian safety.

Device Map

Open House

Residents around Chapman Elementary, as well as parents of children in attendance, were invited to an open house to review and comment on the proposed project. Twelve people attended the open house, and expressed approval for the plan.

Construction

Temporary refuge islands, at Pettygrove and 25th Avenue, were installed in September of 1997 by the Bureau of Maintenance. The Bureau of Maintenance constructed three 14-foot speed bumps on Raleigh and Pettygrove September 7, 1997. The permanent pedestrian refuge island was completed by All Concrete Specialties in September of 1998.

Performance

NW 25th Avenue at Pettygrove
 
NW 25th Avenue is 36 feet wide with curb and sidewalk on both sides. There is also a slight downhill grade from south to north. This street also has Tri-Met service with a stop at Pettygrove. NW 25th Avenue is a Local Service street under Portland’s traffic street classification system with 20-mph school speed zones when children are present. The purpose of such streets is to provide access between private property and higher classified streets. The street attracts a large number of autos due to a four-way stop at its south end (Lovejoy) and a signal at Vaughn Street, which has access to the I-405 freeway. The existing traffic control facilitates cut-through traffic when designated collector streets, like Lovejoy and NW 23rd, are congested. Traffic calming has been implemented in the past in this neighborhood with the use of traffic circles at selected intersections.
 
Vehicle Speeds
 
As graph one shows (next page), vehicle speeds that previously peaked between 23 and 25 mph have been shifted into the range of 20 to 22 mph. The average 85th percentile vehicle speed before construction was 27.6 mph. Since construction the average 85th percentile speed is 25? mph. Before construction 29% of drivers exceeded the posted speed limit of 25 mph. Since construction 16?% of drivers exceed the posted speed limit.
 
Graph 1
 
 
Graph two shows how vehicle speed approaching and departing the pedestrian refuge has changed.
 
Graph 2
 
 
Traffic Volume
 
Traffic volumes measured before construction averaged 7770 vehicles per day (vpd). After bump construction volumes averaged 7680? vpd.
 
NW Raleigh, 26th to 27th
 
NW Raleigh is 36 feet wide with curb and sidewalk on both sides. NW Raleigh is a Local Service street with 20-mph school speed zones when children are present. It previously had traffic circles constructed at the intersections of 26th and 27th Avenues. A speed bump was added mid-block to gain further speed reduction in the high pedestrian school zone.
 
Graph 3
 
 
Vehicle Speeds
 
As graph three shows, vehicle speeds, previously peaked between 20 and 25 mph, have been shifted into the range of 16 to 22 mph. The average 85th percentile vehicle speed before the project was 25.3 mph. Since bump construction the average 85th percentile speed is 22.8 mph and ranges from a low of 22 mph to a high of 24 mph. Before installation of the speed bump 17% of drivers exceeded the posted speed limit of 25 mph and 0.5% exceeded the limit by 10 mph or more. Since bump construction 4.4% of drivers exceed the posted speed limit and 0.08% exceed the limit by 10 mph or more.
 
Traffic Volume
 
Traffic volumes measured before bump construction averaged 1450 vehicles per day (vpd). After bump construction volumes averaged 1180 vpd.
 
NW Pettygrove, 25th to 26th
 
NW Pettygrove is 36 feet wide with curb and sidewalk on both sides. NW Pettygrove is a Local Service street with 20-mph school speed zones when children are present. Two speed bumps were constructed to achieve speed reduction in the high pedestrian school zone where school buses also load and unload students.
 
Vehicle Speeds
 
As graph four shows (next page), vehicle speeds, previously spread between 20 and 28 mph, have been shifted into the range of 16 to 25 mph. The average 85th percentile vehicle speed before the project was 27 mph. Since bump construction the average 85th percentile speed is 22.3 mph and ranges from a low of 20 mph (near the bumps) to a high of 24 mph. Before installation of the speed bumps 26.9% of drivers exceeded the posted speed limit of 25 mph and 0.5% exceeded the limit by 10 mph or more. Since bump construction 3.3% of drivers exceed the posted speed limit and 0.1% exceed the limit by 10 mph or more.
 
Graph 4
 

 
Traffic Volume
 
Traffic volumes measured before bump construction averaged 830 vehicles per day (vpd). After bump construction volumes averaged 656 vpd.
 
Neighborhood
 
Traffic volumes measured on side streets adjacent to NW 25th Avenue, Raleigh and Pettygrove showed no significant increases from volumes measured prior to construction.
 
Summary
 
The Chapman Elementary School Project has succeeded in meeting its primary goals as follows:
 
Reduce vehicle speed around the school: Measurements taken before and after bump construction show a 12-23% reduction in the number of drivers exceeding the posted speed limit.
 
Improve crossing safety on NW 25th at Pettygrove: Vehicle speed at the crossing has been reduced from 27 to 25 mph. The number of drivers exceeding the speed limit has been reduced by 13%. The constructed island provides a location of refuge should a pedestrian begin crossing without an adequate gap to cross the entire street.

School Comments

The new principal stated his observations (his and the comments he's heard from parents and residents) are that they like the devices very much. It definitely slows down traffic, motorists are more aware of pedestrians at the refuge, pedestrians are more mindful of motorists, and that it's had a very positive impact on the safety around the school.

Conclusions

Traffic calming around Chapman Elementary School has enhanced pedestrian safety.