Appendix A Traffic Analysis Report

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TRAFFIC IMPACT ANALYSIS FAIRVIEW STREET IMPROVEMENTS FROM 9T" STREET TO 16T" STREET AND /\ JUNE 2018 BRIDGE REPLACEMENT PROJECT J" SANTA ANA, CALIFORNIA and 5-foot-wide Class II bicycle lanes (with a 2-foot buffer) where they currently do not exist on both sides of Fairview Street between Civic Center Drive and 17th Street. The planned improvements include the construction of a continuous raised median between 9th Street and 161h Street. This continuous raised median would change the intersection of Fairview Street/121h Street from full access to right-in/right-out (RIRO) access. Figure 3 illustrates intersection control changes associated with the project. METHODOLOGY LSA prepared this TIA consistent with the City's Circulation Element and Capacity Calculations and Level of Service Standards. Intersection level of service (LOS) calculations use the intersection capacity utilization (ICU) methodology for signalized intersections, whereas Highway Capacity Manual (HCM) methodology is used for unsignalized intersections. Roadway segment volume -to - capacity ratios (v/c) are determined using the City's theoretical daily roadway capacities. Traffix Version 8.0 computer software was used to determine the LOS at signalized intersections based on the ICU methodology, while Synchro Version 10.1 computer software was used at the unsignalized intersections using the HCM methodology. The ICU methodology was implemented using City requirement inputs including 5 percent loss time, 1,700 vehicles per hour per lane (vphpl) capacity for through lanes, and 1,600 vphpl capacity for turn lanes. The ICU methodology compares the v/c ratios of conflicting turn movements at an intersection, sums these critical conflicting v/c ratios for each intersection approach, and determines the overall ICU. The HCM methodology calculates the delay experienced by vehicles passing through the intersection. The resulting ICU or delay is expressed in terms of LOS, where LOS A represents free -flow activity and LOS F represents overcapacity operation. LOS is a qualitative assessment of the quantitative effects of such factors as traffic volume, roadway geometrics, speed, delay, and maneuverability on roadway and intersection operations. The following table describes in detail LOS criteria for intersections. LOS Description A No approach phase is fully utilized by traffic, and no vehicle waits longer than one red indication. Typically, the approach appears quite open, turns are made easily, and nearly all drivers find freedom of operation. B This service level represents stable operation, where an occasional approach phase is fully utilized, and a substantial number are nearing full use. Many drivers begin to feel restricted within platoons of vehicles. C This level still represents stable operating conditions. Occasionally, drivers may have to wait through more than one red signal indication, and backups may develop behind turning vehicles. Most drivers feel somewhat restricted, but not objectionably so. D This level encompasses a zone of increasing restriction approaching instability at the intersection. Delays to approaching vehicles may be substantial during short peaks within the peak period; however, enough cycles with lower demand occur to permit periodic clearance of developing queues, thus preventing excessive backups. E Capacity occurs at the upper end of this service level. It represents the most vehicles that any particular intersection approach can accommodate. Full utilization of every signal cycle is attained no matter how great the demand. F This level describes forced flow operations at low speeds, where volumes exceed capacity. These conditions usually result from queues of vehicles backing up from a restriction downstream. Speeds are reduced substantially, and stoppages may occur for short or long periods of time due to the congestion. In the extreme case, speed can drop to zero. LOS = level of service P:\WKE1702\Traffic\doc\Traffic Analysis Report rev - Caltrans Comments.docx u06/07/18» 4