1667236 - Intersection Designs that Promote Active Transportation

Active transportation refers to walking, biking, and scooting, etc. The infrastructures that accommodates active transportation include pedestrian facilities and bicycle facilities. The safety and connectivity of bicycle facilities play a major role in influencing road users’ decisions on whether or not to use active transportation. The extent of people using active transportation is a reflection of the safety, quality of life, and efficiency of the transportation system. There are many benefits associated with having a fair share of active transportation in the traffic mix, such as reduced traffic congestion and fuel consumption, reduced need for parking spaces, and improvements in public health and equity in transportation, etc. In the Netherlands, 25% of all trips are made using bicycles, whereas in the US, the percentage is only 1.5%, reflecting a severe deficiency in our bicycle infrastructure. Governments at all levels in the US have started to realize this problem, under the backdrop of increasing fatalities and injuries to vulnerable road users, and are rolling out plans and policies to improve the roadways and encourage people using active transportation. Besides planning level policy guidance, intersection designs set the tone of the intended road user experience and have strong influence to the roadway segment designs. The current US main stream bicycle facility designs emphasize shared use of the road between bicyclists and motor vehicles. In this practice, bicycle lanes are sandwiched between through right-turning vehicles at the intersection. This design is often implemented at large high speed intersections such as the State Route 56 @ Bruce B Downs Boulevard in Wesley Chapel, FL, where both intersecting roads have 55 mph speed limit, all approaches have triple left-turn lanes, triple through lanes, and single or double right-turn lanes, creating a dangerous environment for the cyclists. Such facilities, regardless of the length of miles installed, will not be embraced or used by typical cyclists, and become waste investment that have no impact of inducing  meaningful shifts in traffic modes. In this presentation, we will discuss the problems in the current US bicycle facility design, the benefits of active transportation, and present the concept of protected intersection design, which use corner islands and raised approach islands to separate bicycle traffic from vehicle and pedestrian traffics, bicycle left-turns are done through two crossing movements along the perimeter of the intersection. This design infuses a sense of security to vulnerable road users at the intersection, and naturally influences the extension of bicycle and vehicle traffics separation to roadway segments. We will present 8 or more distinct examples of implementing this design, and use field videos to illustrate that good geometric designs are necessary to promote good user behaviors for safety and operation at the intersection.