Congestion Relief – We must use every tool at our disposal


Congestion Relief – An engineering problem that needs input from other non-engineer experts
The reading “Why More Roads Lead to More Traffic (and What to Do About It)” by Tom Vanderbilt presented some interesting facts about road congestion and its potential workarounds. The chapter explains interesting concepts such as:
·         Latent demand or induced travel: The idea that demand for a free public good, such as the roadway, will not reach equilibrium until either the resource is maxed out or the resource stops being free. New travelers will be attracted to the free and available road, while current travelers will use the road more often until either the road becomes congested or a fee, such as a highway toll, is implemented.
·         Congestion Pricing: A strategy that combats latent demand by tolling a stretch of roadway or an entire area within a city. Some European cities such as Oslo and London charge a fee for entering their city center on an automobile. This strategy decreases congestion and allows other transportation modes, such as buses and bicycles, to travel at ease and move at faster speeds during peak hours.
·         The diminishing returns of roadway expansion:  Vanderbilt explains that adding road lanes to an intersection or to an entire roadway is a process that decreases the individual efficiency for each roadway lane. Safety guidance such as the prohibition of “permissive” left turns on green for roadways with more than one left turn lane and factors such as “friction” among vehicles travelling on adjacent lanes contribute to a decreased efficiency for every lane added to the roadway.
All of these concepts can help planners and policy-makers understand and tackle traffic congestion from its roots.  However, in my opinion, the author overlooks important pieces of the puzzle by focusing only on automobiles and occasionally in transit: walking and biking. These modes of transportation have a real, often unexploited, positive impact on motorized travel times. Consider this example: According to Robert Geller, Portland’s Bicycle Coordinator, vehicle traffic on four Portland bridges connecting downtown with the east side saw an increase of 12% in vehicle volumes. However, congestion and travel delay across these bridges has remained the same. How is this possible? The growth has been absorbed bicycles and not automobiles. Common engineering solutions would be to add lanes to the bridges and to the intersections at the ends which would have been undoubtedly cost millions of dollars. Instead, Portland made sure that its bridges could safely move bicyclists from one shore of the Willamette River to the other which saved the city millions in infrastructure spending.

Written by: Santiago Espinosa Wild

Edited by: Sophie Appell

Bibliography

Geller, R. (2011) How Portland Benefits from Bicycle Transportation.
Retrieved from: https://www.portlandoregon.gov/transportation/article/371038

Vanderbilt T. (2008) Why More Roads Lead to More Traffic (and What to Do About It), Traffic. Why we drive the way we do.  (153-175) New York, NY: Vintage Books.

Comments

  1. Totally agree that cycling and walking are overlooked in many discussions to reduce congestion. However, although active transportation is convenient and efficient in many urban areas, consistent use of these modes can also difficult for many communities that live in less dense settings and far from employment opportunities or goods and services. I think cities and surburban areas (and hopefully some rural areas) can view active transportation as a complement to other modes, part of an interconnected network that provides a variety of convenient options without the use of a car. First mile/last mile strategies are some of the most popular forms of this network approach -- helping people get to/from various forms of public transportation -- particularly for bikesharing companies as they determine geographic distribution of their infrastructure. We can certainly go much further in synchronizing these various transportation systems -- for example, by creating a single farecard or account # that can activate (and link with discounted rates) public and active transportation options. And to encourage higher ridership levels, the recent introduction of electric-assist bikesharing options (such as JUMP bikes) can help overcome the geographic and weather-related barriers.

    Of course, the single thing that will help most is more investment in protected and safe bike/ped infrastructure...but that seems to be a slow process in many areas.

    ReplyDelete

Post a Comment

Popular posts from this blog

Invisible Cyclists

Bicycle Parking/Storage Arrangements

Intersection of gender and age in transportation