Transportation Planning on Trial: The Clean Air Act and Travel Forecasting.

Land use attorney Mark Garrett and University of California (Los Angeles and Berkeley) faculty scholar Martin Wachs have pooled their talents to document the impact of the Clean Air Act on long-standing approaches to travel forecasting. The authors argue that legal challenges to planning decisions have led to a major re-examination of transportation planning methodology. The passage of the 1970 Clean Air Act Amendments expressed a new national policy which closely links air quality and transportation, with new approaches to forecasting, and the development of new models. The 1990 amendments to the Act, and the passage of the Intermodal Surface Transportation Efficiency Act (ISTEA) strengthened that linkage. This book chronicles events and actions leading to new travel forecasting approaches that have major implications for regional and metropolitan transportation planning.

Garrett and Wachs selected the San Francisco Bay Area as the venue for their research. Environmental groups challenged the adequacy of planning efforts by the Metropolitan Transportation Commission (MTC), the regional transportation planning agency. Litigation pointed up deficiencies in the current approaches to travel modeling and analysis. Plaintiffs in a lawsuit against the MTC contended that the planning process was inadequate and that its content was flawed. They argued that the agency did not consider future land use implications of new freeway construction, failed to implement control measures necessary to achieve traffic reduction and cleaner air goals contained in the regional transportation plan, and failed to meet other Clean Air Act mandates required of the urban transportation planning process. They also argued that the models …