University of California Transportation Center

This paper documents the current efforts of transportation planning and air quality policies to reduce traffic congestion in metropolitan Phoenix. In metropolitan Arizona, the weakness of adopted land use controls, preference for single occupant commuting, and the importance of regional water and air quality issues guide transportation planning.

Adopted transportation and employee trip reduction measures include a 1985 metropolitan Phoenix referendum approving a one-half cent sales tax for construction of a 231-mile freeway addition and preparation of a metropolitan rapid transit plan, defeated on March 28, 1989. The 1988 Arizona Legislature Omnibus Air Quality bill mandates employee commuter distance and mode baseline studies yearly, completed employer trip reduction plans and a reduction of five percent of the average vehicle miles traveled in each of the next two years.

A pre-test survey documents potential problems with the current analysis approach. The employee baseline survey relies on stated or perceived distance which may not accurately measure average vehicle miles traveled. Analysis of a survey of 400 Arizona State University students compared their stated commuting distance with the actual distance as measured by straight-line and grid measurements.

Both technical problems and the lack of broad-based support for alternatives to single occupant commuting suggest that current metropolitan Phoenix planning efforts to reduce traffic congestion by regulating employee travel will be part of a long-term learning process.