Encouraging Active Transportation in Tucson By: Loran Shamis Mentor: Arlie Adkins, PhD. Sbe 498 Fall 2015 Table of Contents

Safety Case Study: Portland, OR

One of the strategies utilized was traffic-calming investment. The city collected data concerning collision occurrence pre- and post-implementation with regards to three types of strategies- roundabouts/circles, 22-foot speed bumps and 14-foot speed bumps. In all three instances, collisions were reduced; an average of 30.19 percent reduction for roundabouts, 35.71 percent reduction for 22-foot speed bumps, and 39.34 percent reduction for 14-foot speed bumps (The City of Portland, Oregon). Confirming that traffic calming is successful at reducing collision occurrence allows the city to identify areas where collisions need to be reduced by implementing these same strategies.

Portland is also investing in “road diets”, which is the strategy of converting space dedicated to solely motorists in order to create a system that is more balanced between all modes of transportation, including pedestrians and cyclists. Doing this assists in better organizing the streets and helps to improve predictability among commuters. Some motorists have shown opposition to this strategy because it takes infrastructure away from motor vehicles but appraisal has been seen among business districts and residents in neighborhoods where road diets have been implemented, walkers and cyclists.

One example of a street that experienced “road dieting” in Portland is Northeast Multnomah Street (shown below in figure 3). The street once consisted of two lanes of traffic each way, a center turning lane and standard bike lanes. After implementing the diet, the street consists of one lane of travel in each direction, a center turning lane and protected bike lanes on each side of the road. The bike lanes are protected from motor traffic by parked cars, painted buffers, flexible bollards and/or planters. The width of the lane varies between four and seven feet depending on the location and the buffers vary in width anywhere from two to eleven feet. Cyclists and pedestrians are the most vulnerable users of the street during a collision; thus, it is important to have some sort of physical or visual barrier between traffic and active commuters.

Lastly, since intersections are a big concern for the safety of active commuters, Portland has invested a more efficient signal system that helps to better regulate and enforce full stops by cyclists. Some intersections utilize loop detection, which consists of a marked circle or rectangle at the appropriate distance from the intersection that detects when a bike is stopped within the shape, signaling the light to change to green. The signal is more effective if the cyclist makes a full stop within the marked area and remains there until the traffic light changes to green. Other intersections utilize video detection for the same purpose. Pedestrian buttons are also available for those who are commuting by foot with areas of refuge in intersection medians.