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146 <br /> RESEARCH TRIANGLE LOGISTICS PARK TRAFFIC IMPACT ANALYSIS <br /> Capacity Analysis <br /> June 4, 2020 <br /> 6.0 TRAFFIC ANALYSIS <br /> Capacity analyses were performed for the roadway network in the project study area. The traffic analysis program <br /> Synchro Version 10 was used to analyze all signalized and stop-controlled intersections according to methods put <br /> forth by the Transportation Research Board's Highway Capacity Manual (HCM)4.The Highway Capacity Manual <br /> defines capacity as"the maximum rate of flow at which persons or vehicles can be reasonably expected to traverse a <br /> point or uniform section of a lane or roadway during a specified time period under prevailing roadway,traffic, and <br /> control conditions, usually expressed as vehicles per lane per hour." <br /> Level of service(LOS) is a term used to describe different traffic conditions and is defined as a"qualitative measure <br /> describing operational conditions within a traffic stream, and their perception by motorists/or passengers." LOS <br /> varies from Level A, representing free flow,to Level F where traffic breakdown conditions are evident. At an <br /> unsignalized intersection, the primary traffic on the main roadway is virtually uninterrupted. Therefore,the overall <br /> delay for the intersection is usually less than what is calculated for the minor street movements. The overall <br /> intersection delay and the delay for the intersection's minor movement(s)are reported in the summary tables of this <br /> report. Generally, LOS D is acceptable for signalized intersections in suburban areas during peak periods. With the <br /> current method of reporting LOS for unsignalized intersections, it is not uncommon for some of the minor street <br /> movements to be operating at a LOS F during peak hour conditions and that is not necessarily indicative of an area <br /> that requires improvements. <br /> Capacity analyses were completed in accordance with NCDOT Congestion Management Capacity Analysis <br /> GuidelineS5 . It should be noted that the analyses includes permitted + protected signal phasing in-addition to right- <br /> turn-on-red at the intersection of Old NC 86 at Waterstone Drive/Rippy Lane.This provided results more indicative <br /> of field conditions as the signal currently operates with a flashing yellow arrow.Table 3 presents the criteria of each <br /> LOS as indicated in the HCM5. <br /> Table 3: Level of Service Criteria <br /> Level of Service Signalized Intersection Unsignalized Intersection <br /> (LOS) Control Delay Control Delay <br /> (seconds/vehicle) (seconds/vehicle) <br /> A <_ 10 <_ 10 <br /> B >10 and<_20 >10 and <_ 15 <br /> C >20 and<_35 >15 and <_25 <br /> D >35 and<_55 >25 and <_35 <br /> E >55 and<_80 >35 and <_50 <br /> F 1 >80 1 >50 <br /> 23 <br />