Figure 2 Self-Reinforcing Cycle

An extensive literature provides evidence on historic impacts of transportation, the impacts of urban freeways, the impacts of rail transit, and general relationships between transportation investments and development patterns:

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  The streetcar systems and commuter rail of the turn of the century made it possible for population to spread out from the central city core and to live at increasing distances from the workplace (Warner, 1962; Fogelson, 1993; Mohl, 1985; Goldfield and Brownell, 1990)
  
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  Decentralization accelerated with the adoption of the automobile and truck in the 1920’s and 1930’s, and has continued to this day (Muller, 1981, 1995; Lowry, 1988)
  
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  Access to highways is one of the most important factors determining the location of firms (Lyne, 1988; Button et al., 1995; Calzonetti and Walker, 1991)
  
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  The interchanges of these high speed highways have given some suburban locations the level of accessibility that previously only occurred in central business districts (Muller, 1995; Leinberger, 1996; Hughes and Sternlieb, 1988)
  
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  In regions with extensive networks, such as Atlanta, Columbus, and Kansas City, the interstate highways have been one of many factors supporting the geographic spread of the region and the development of suburban activity centers at the nodes of interstate network (TRB, 1999). Businesses will outbid households for locations along arterials and highways and especially at the nodes in the transportation system (Downs, 1992)
  
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  Beltways may merely redistribute development, shifting growth from the CBD to the suburbs and thus contributing to the decentralization of cities (Payne-Maxie Consultants, 1980)
  
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  There is a strong positive correlation between highway accessibility and land prices, after controlling for a wide variety of other variables, including parcel size and square footage of development (Kockelman, 1997)
  

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  Proximity to light rail transit improves residents’ accessibility to the central business district and other urban areas with employment opportunities (Al-Mosaind et al., 1995)
  
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  The interactions of households, businesses, developers, and government determine the physical arrangements of land uses in urban areas (TRB, 1999)
  
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  The supply of developable land is constrained by the public and private resources available to extend roads and other infrastructure systems such as water, sewer, storm water, and transportation systems (Kelly, 1993; Nelson and Duncan, 1995; Miles et al., 1996)
  
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  Typically many of these attributes, such as the supply of developable land, lower costs of development or leasing, access to labor, good access to highways, are more readily available on the urban fringe than in already developed areas (White, Binkley, and Osterman, 1993)
  
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  Major improvements to existing transportation infrastructure should have a strong, positive effect on nearby real estate values. However, the impacts may be highly localized and of a much lesser degree than those caused by the original construction (Landis et al., 1995; Tomasik, 1987)
  
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  Park space and retail-jobs accessibility proved exert positive effects on home valuation and location choice (Srour, Kockelman, and Dunn, 2001)
  

Transportation investments and policies may be divided into four general categories: highway and automobile-related investments (e.g., new facilities and construction and added lanes), travel demand management (e.g., pricing policies and taxations), transit investments and policies (e.g., new transit facilities and service and fare changes), and non-motorized mode facility investments and policies (e.g., bike/pathway improvement). The impacts of these types of investments and policies are summarized in Table 2. These impacts may include shifts of population and jobs toward more accessible locations such as downtown areas, stations, and major transit corridors, increase in land values, and concentration of development (National Cooperative Highway Research Program, 1999). In their study of the Bay Area Rapid Transit (BART) system, Cervero and Landis (1997) found significant increases in population and employment densities, multi-family housing, retail and commercial establishments around BART stations. Undesirable impacts of transportation investments and policies may include decentralization of population and employment to suburban or exurban areas that imposes a variety of costs, including increased economic costs to construct roadway facilities, increased land requirements for roads, environmental and aesthetic cost from reduced greenspace, and so on (Badoe and Miller, 2000; Litman, 1999). Even though Giuliano (1995) indicates that transportation investments do not have a consistent or predictable impact on land use, she states transportation investments are viewed as critical to growth-management policy objectives.