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123 <br /> Kimley)>>Horn White Cross Retail-Orange County, NC <br /> 6.0 Capacity Analysis <br /> Capacity is defined as the maximum number of vehicles that can pass over a particular road <br /> segment or through a particular intersection within a set time duration. Capacity is combined with <br /> Level-of-Service (LOS) to describe operating characteristics of a road segment or intersection. <br /> LOS is a qualitative measure that describes operational conditions and motorist perceptions <br /> within a traffic stream. The Highway Capacity Manual defines six levels of service, LOS A <br /> through LOS F, with A representing the shortest average delays and F representing the longest <br /> average delays. LOS D is the typically accepted standard for signalized intersections in urbanized <br /> areas. For signalized intersections, LOS is defined for the overall intersection operation. <br /> For unsignalized intersections, only the movements that must yield right-of-way experience <br /> control delay. Therefore, LOS criteria for the overall intersection is not reported by <br /> Synchro/SimTraffic Version 11 or computable using methodology published in the Highway <br /> Capacity Manual. It is typical for stop sign controlled side streets and driveways intersecting <br /> major streets to experience long delays during peak hours, while the majority of the traffic <br /> moving through the intersection on the major street experiences little or no delay. <br /> Table 6.0 lists the LOS control delay thresholds published in the Highway Capacity Manual for <br /> signalized and unsignalized intersections, and all capacity analyses are included in the Appendix <br /> and are briefly summarized in the following sub-sections. <br /> Table 6.0 <br /> Level-of-Service Control Delay Thresholds <br /> Level-of- Signalized Intersections- Unsignalized Intersections-Average <br /> Service Control Delay Per Vehicle Control Delay [sec/veh] & Qualitative <br /> [sec/veh] Operational Description <br /> A < 10 < 10 <br /> B > 10-20 > 10- 15 Short Delays <br /> C >20-35 > 15-25 <br /> D >35-55 >25-35 <br /> E >55-80 >35-50 Moderate Delays <br /> F >80 >50 Long Delays <br /> Existing peak hour factors (PHF's) were used where current conditions exceed the default value <br /> of 0.90, which was also used at new intersections. Existing heavy vehicle percentages were used <br /> where current conditions exceed the default value of 2%. <br /> 12 <br />