05-19-16 Regular Meeting of the Planning and Zoning Commission

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EXHIBIT C on a number of variables, including the quality of the signal progression, the cycle length, the green time ratio, and the v/c ratio for the lane group or approach in question. LOS is directly related to the control delay value. Note that the LOS thresholds are different for signalized intersections as compared to unsignalized intersections. The criteria for stop-controlled intersections have different threshold values than to those for signalized intersections primarily because drivers expect different levels of performance from distinct types of transportation facilities. The expectation is that a signalized intersection is designed to carry higher traffic volumes than a stop-controlled intersection. Thus, a higher level of control delay is acceptable at a signalized intersection for the same level of service. At a two-way stop-controlled intersection, LOS is defined for each minor movement, but not for the intersection as a whole. Table 2. LOS Thresholds for Signalized and Unsignalized Intersections. Level of Service (LOS) Signalized Intersections Unsignalized Intersections Control Delay Per Vehicle Control Delay Per Vehicle (sec/veh) (sec/veh) A 0-10 B >10-20 >10-15 C >20-35 >15-25 D >35-55 >25-35 E >55-80 >35-50 F >80 >50 Table 3 summarizes the existing intersection LOS for each of the study intersections during each critical peak hour identified for this study. The delays reported within this report represent the average delay in the peak 15-minute time period within each peak hour, not the average delay over the entire peak hour as a whole. As shown in Table 3 and Table 4, all intersections in the study area are currently operating at very good levels of service in the peak hour (at LOS B/C), with LOS D as the typical threshold for intersection operations in urban and suburban environments. From field observation, the existing weekday signal timings are quite appropriate for the existing traffic volume conditions and the signal operation is generally characterized by crisp movement phase to phase and good coordination. The signal timings are typically running only minimum phase lengths as it appears that demand is relatively light most of the day, even with an assumed growth rate of 3% per year, the average control delays would not be estimated to change significantly from existing 2016 to Page 9 Voigt Associates, Inc. Project 30605 GCP 16 Street Traffic Impact Analysis th March 2016 Prepared for Generational Commercial