Left turns on amber and red from exclusive double left-turn lanes

This article presents some results of a larger study directed at estimating the saturation flows of exclusive double left-turn lanes. The findings reported in this article are based on observations of a total of 3458 completed left turns from exclusive double left-turn lanes on 14 intersection approaches in three Texas cities. The objective of the portion of the research reported here was to investigate the distributions of left turns on amber and red from exclusive double left-turn lanes during saturated conditions (i.e., for queue lengths of five or more vehicles/lane).