In appreciation of the fact that longer-run considerations are particularly important in the development of urban transportation, during the past three decades American transportation planning has been employing increasingly sophisticated approaches to the future. This article discusses four phases in this evolution, with a given focus dominant in each period. During the first period, following on the initial provision of federal government funds for the construction of highways in and around cities, major reliance was based on simple projections of travel demand in metropolitan regions, based mainly on current patterns. This was followed by an approach which focused on an analysis of impacts on transportation systems of projected land uses, based on forecasts of population and economic grwoth for a target year, on the assumption that facilities were to be provided to move all vehicles that wanted to move from here to there at least possible cost. The third period was characterized by an increasing consciousness of the value of articulating national and local goals in making transportation decisions, going beyond narrow economic and mobility objectives, and including the notion of trade-offs among goals. The most recent period discussed is one characterized by rising interest in futures studies, using methods such as "delphi" and cross-impact analysis and approaches such as "alternative futures," as well as a search for achieving flexibility in transportation development and for means of limiting resource commitment in the face of the uncertainties of the future ("keeping options open"). /TRRL/

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    Radarweg 29
    Amsterdam,   Netherlands  1043 NX
  • Authors:
    • Perloff, H S
    • Flaming, D J
  • Publication Date: 1976-6


  • English

Media Info

  • Features: References;
  • Pagination: p. 153-173
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00142158
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Report/Paper Numbers: Analytic
  • Files: ITRD, TRIS
  • Created Date: Aug 4 1981 12:00AM