In 1992, an Applicant’s Guide and a Reviewer’s Guide to Traffic Impact Analyses to standardize the methodologies for conducting traffic impact analyses (TIAs) in Indiana were developed for the Indiana Department of Transportation (INDOT). The methodologies were meant to help streamline the process of preparing and reviewing TIAs. The methodology is applicable for other transportation and government entities as well. Because 20 years have passed since the publication of the guides, INDOT wished to evaluate how effective the guides have been, determine what in the guides has worked well, revise parts of the guides that have not worked well, and add improvements and changes that have occurred since the guides’ publication. Brief explanations of innovative intersection alternatives such as roundabouts, median U-turns (MUT), restricted-crossing U-turns (RCUT), displaced left-turns (DLT), and quadrant roadways (QR) are provided to increase awareness of these possible designs. Some of the innovative designs were compared against a two-way stop-controlled intersection and a conventional signalized intersection for varying volumes on minor street approaches. The median U-turn design seemed to perform better at higher, more balanced flows whereas the roundabout performed better for unbalanced flows. At times, a development affects roads in more than one jurisdiction. Ideas are presented that may facilitate the inclusion of all affected parties early in the development process to improve communication, address all possible effects of the development and better satisfy all affected parties.

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traffic impact analysis, traffic impact studies, trip generation, access management, traffic microsimulation, pass-by trips, internal trips

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Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, Indiana

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