Herbert S. Levinson

Urban Development and Traffic Congestion

The objectives of this paper are to view contemporary traffic congestion as a phenomenon that has always existed within cities throughout history, and to recommend pragmatic modern day solutions to address/manage the congestion problem. This has been achieved by a review of the factors that create congestion, and of the roles that electric streetcars, rapid transit lines, suburban rail lines, and automobiles have played in the decongestion of cities. Examples of outcomes from past transportation improvements are illustrated to show that regional changes in transportation access create new development nodes of activities outside cities that reduce development pressures in the central city (hence reducing congestion growth there) and increase the attraction of peripheral areas to major land developments that lead to increased congestion in these areas. The paper proposes a mix of transportation and land development strategies to minimize the negative effects of urban traffic congestion in the future.

The Costs and Other Consequences of Traffic Congestion

In an increasingly fast paced and globally oriented economy, the efficient movement of persons and goods is a competitive necessity [1]. Traffic congestion adversely impacts quality of life and economic productivity in metropolitan areas. It increases fuel consumption, the cost of traveler and freight movement, the number of crashes, and tailpipe pollutants harmful to human health.

Measuring Traffic Congestion

Congestion in transportation occurs when the occupancy of spaces (roadways, sidewalks, transit lines and terminals) by vehicles or people reaches unacceptable levels of discomfort and delay.

Insufficient Capacity, Growth in Population, Employment, and Car Use

Traffic demand has spread in post-World War II metropolitan America as a result of changing patterns of where people live and work, and how they travel.

Managing Nonrecurring Congestion

Nonrecurring congestion accounts for over half of all traffic delays in the United States [1] and accounts for up to 2/3 of traffic delays in urban areas larger than one million population [2].

Overview of Mitigation Strategies that Reduce Traffic Demand

Managing travel demand is increasingly recognized as a means of addressing urban traffic congestion—especially in large metropolitan areas. Commonly called “transportation demand management” (TDM), the strategy focuses on reducing the demand for single occupant vehicles. Emphasis is typically placed on reducing vehicle-miles of travel (VMT).

The Role of Access Management in Sustainable Development

Efforts to manage highway access are occasionally characterized as inconsistent with livable communities, complete streets and smart growth. One reason is the past emphasis placed on management of vehicular access, which some view as symptomatic of auto-oriented planning and therefore counter to multimodal goals. Another reason is a lack of understanding of the role of access management in advancing sustainable development and supporting walking, bicycling and transit use. This paper explores the role of access management in accomplishing a more sustainable approach to transportation and development planning in the US. Topics include land use and transportation relationships, network planning and activity center strategies, and site design concepts for urban arterial development. Policy changes are suggested.

Overview of the Causes of Congestion

Traffic congestion results from the imbalance between the supply of and the demand for transportation facilities

Direct Demand Strategies—Regulatory Restrictions

This congestion relief strategy entails reducing traffic demand through regulatory road use strategies that limit the number and type of vehicles from using roadways or from entering certain areas that become congested when vehicles access is not restricted.

Indirect Demand Strategies—Land Use, Transit, Alternative Modes

This chapter describes strategies that reduce motor vehicle use in urban areas by 1) improving public transportation services (where appropriate) and 2) implementing land use policies that support travel mode alternatives to the automobile.