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Mr. Rob Carnachan Page 5 March 6, 2025 <br />Intersection Level of Service Methodologies <br />The study intersections were analyzed using methodologies published in the Highway Capacity Manual (HCM), 6th <br />Edition, Transportation Research Board, 2016. This source contains methodologies for various types of intersection <br />control, all of which are related to a measurement of delay in average number of seconds per vehicle. <br />The Levels of Service for the intersections with side street stop controls, or those which are unsignalized and have <br />one or two approaches stop controlled (East Harney Lane/Site Access and East Harney Lane/ Clements Road), were <br />analyzed using the “Two-Way Stop-Controlled” intersection capacity method from the HCM. This methodology <br />determines a level of service for each minor turning movement by estimating the level of average delay in seconds <br />per vehicle. Results are presented for individual movements together with the weighted overall average delay for <br />the intersection. <br />The study intersection with stop signs on all approaches (East Harney Lane/Jack Tone Road) was analyzed using <br />the “All-Way Stop-Controlled” intersection methodology from the HCM. This methodology evaluates delay for <br />each approach based on turning movements, opposing and conflicting traffic volumes, and the number of lanes. <br />Average vehicle delay is computed for the intersection as a whole, and is then related to a Level of Service. <br />The study intersection that is currently controlled by a traffic signal (East Harney Lane/SR-88) was evaluated using <br />the signalized methodology from the HCM. This methodology is based on factors including traffic volumes, green <br />time for each movement, phasing, whether the signals are coordinated or not, truck traffic, and pedestrian activity. <br />Average stopped delay per vehicle in seconds is used as the basis for evaluation in this LOS methodology. For <br />purposes of this study, delays were calculated using signal timing obtained from Caltrans. <br />The ranges of delay associated with the various levels of service are indicated in Table 5.