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Frewert Traffic Impact Study signalized intersections was calculated using Synchro 10 analysis software and was correlated to a LOS designation as shown in Table 1. Table 1:Signalized Intersection Delay and LOS Definitions Average Level of Service Description Control Delray Signal progression is extremely favorable.Most vehicles arrive during the A green phase and do not stop at all.Short cycle lengths may also 10.0 or less contribute to the very low vehicle delay. Operations characterized by good signal progression and/or short cycle 8 lengths. More vehicles stop than with LOS A,causing higher levels of 10.1 to 20.0 average vehicle delay. Higher delays may result from fair signal progression and/or longer cycle lengths. Individual cycle failures may begin to appear at this level.The C 20.1 to 35.0 number of vehicles stopping is significant,though may still pass through the intersection without stopping. The influence of congestion becomes more noticeable, Longer delays may result from some combination of unfavorable signal progression, D 35,1 to 55.0 long cycle lengths,or high volume-to-capacity(V/C}ratios. Many vehicles stop and individual cycle failures are noticeable. This is considered to be the limit of acceptable delay.These high delay values generally indicate poor signal progression, long cycle lengths,and E 55.1 to 80.0 high volume--to-capacity(V/Q ratios. Individual cycle failures occur frequently. This level of delay is considered unacceptable by most drivers.This F condition often occurs with oversaturation,that is,when arrival flow rates greater than exceed the capacity of the intersection. Poor progression and long cycle 80,0 lengths may also be major-contributing causes of such delay levels. Source:Highway Capacity Manual 6"Ed.,Chapter 18(Transportation Research Board,2010) Average Control Delay per Vehicle in seconds Unsignalized Intersections The study intersections under stop control (unsignalized)were analyzed using the 61h Edition HCM Operations Methodology for unsignalized intersections described in Chapter 20 (HCM 611 Ed.). LOS ratings for stop-sign controlled intersections are based on the average control delay expressed in seconds per vehicle.At the side street, one-way or two-way stop controlled intersections, the control delay is calculated for each movement, not for the intersection as a whole. For approaches composed of a single lane, the control delay is computed as the average of all movements in that lane.The weighted average delay for the entire intersections is presented for all-way stop controlled intersections.The average control delay for unsignalized intersections was calculated using Synchro 10 analysis software and was correlated to a LOS designation as shown in Table 1a. Page 19 TJ KM