Evaluation of potential flashing yellow arrow implementation in the city of Elk Grove using microsimulation

The main objective of this project was to evaluate the operational performance of select signalized intersections in the City of Elk Grove before and after the implementation of protected/permissive left-turns (PPLT) with flashing yellow arrows (FYA). The report is intended to assist with the prioritization of the intersection locations that will provide the greatest reduction in vehicular delay. The implementation of flashing yellow arrows is a pilot program for the City of Elk Grove. This project ranked locations within the city that would benefit most from the installation of flashing yellow arrows. The primary focus of this project was on the operational aspects of existing signalized intersections before and after the implementation of flashing yellow arrow protected/permissive phasing. Some of the data was provided by the City of Elk Grove, and the remaining data was collected in the field. The scope of the analysis included 11 locations identified by the city as possible locations for FYA. All approaches in the 11 locations were screened using the protected/permissive left-turn criteria developed using the city's draft left-turn phasing selection criteria which includes posted speed, volume, approach geometry and other intersection characteristics. Using the Synchro traffic analysis software, the existing vehicular delay (baseline) and expected vehicular delay (with flashing yellow arrows) were calculated and then compared. The ranking performance measure was based on the before and after delay reduction per intersection. The top three ranked intersections were Harbour Point Drive at Renwick Avenue, Lewis Stein Road at West Stockton Boulevard and Willard Parkway at Matina Drive.