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 The intersection of Fairview Street at 16th Street experiences a worsening of HCM based delay values in the 2040 p.m. peak hour from an acceptable 24.9 second/vehicle LOS "C" in the No Build condition to an unacceptable 41.7 second/vehicle LOS "E" in the Build condition. As previously mentioned, the HCM delay value represents the calculated delay of the worst performing movement in a given intersection and not indicative of the experience of the majority of vehicles traveling through these intersections. As this resulting additional deficient operation is indicative of only the worst performing movement, in this case the 5 eastbound left -turning vehicles in the p.m. peak hour, this delay value and LOS is not considered to be indicative of the overall intersection and is not considered a significant impact. It should be noted that implementation of the project would result in an additional unsatisfactorily operating intersection (the intersection of Fairview Street and Civic Center Drive) compared to the deficient intersections identified under the 2040 No Build condition. Regional growth between existing and 2040 No Build conditions would contribute to the unacceptable peak -hour operations at the intersection of Fairview Street at Civic Center Drive to result in such a level of significant impact. As shown previously in Table F, the proposed increase in roadway capacity to Fairview Street south of 161h Street is anticipated to accommodate both ambient existing to 2040 traffic growth and regional north -south regional traffic rebalancing at satisfactory LOS D. This is an improvement over both existing and 2040 No Build overcapacity traffic conditions. UNSIGNALIZED QUEUING ANALYSIS To determine the necessary turn pocket lengths at the intersections of Fairview Street/16th Street and Fairview Street/9th Street that would be affected by the project, LSA conducted an HCM based queuing analysis for 2040 Build traffic conditions. Table G shows the results of this queuing analysis. Table G: 2040 Build Fairview Street Turn Pocket Queuing Intersection Movement Existing Pocket Length (feet) 95` percentile queue (feet)' AM Peak Hour PM Peak Hour Fairview Street/161Street Northbound Left 50 < 25 < 25 Fairview Street/9` Street Northbound Left 55 33 38 Southbound Left 95 48 < 25 1 Queue length is based on a design vehicle length of 25 feet. Queue lengths less than one vehicle in length are noted as "< 25" to signify that a minimum of one vehicle length of queueing storage should be provided. Because the existing intersection geometrics have storage lengths that exceed the calculated queue lengths, modifications to existing pocket lengths are not necessary to accommodate 2040 Build traffic queues and are not recommended at this time. Appendix B provides HCM calculated queues on the Synchro LOS worksheets. MITIGATION MEASURE As described previously, the proposed improvement of Fairview Street from four through lanes to six through lanes could result in a significant impact at the intersection of Fairview Street and Civic P:\WKE1702\Traffic\doc\Traffic Analysis Report rev - Caltrans Comments.docx u06/07/18» 18