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�1 CITY OF SANTA ANA operations. For Diamond Interchanges, when possible, off ramp phase single entry operations coupled with coordinated phase through band with offset off ramp band flows should be employed for both directions. Dependent on spacing between off ramp intersections, dual entry operations may be appropriate. C. Consultant shall present from 2 to 3 timing plan operational scenarios dependent on coordinated and crossing arterial traffic conditions for timing plan implementation and the "when", "who", and "how". These scenarios will be part of the initial presentation of the corridor existing conditions, proposed groupings and cycle lengths report. Sub-Task 4.4: Coordinated Optimized Traffic Signal Timing A. Based on a consensus developed from discussions of the scenarios presented and then approved by the Agencies, the consultant shall prepare Coordinated Optimized Traffic Signal Timing Plans for the four (4) Caltrans intersections. B. Consultant will measure the saturation flow rates at key project intersections during one peak hour where the overall intersection volume-to-capacity ratio is greater than or equal to 0.8 as a calibration for the Synchro model. Timing parameters shall provide adequate crossing time to accommodate pedestrians within the phase split. C. Consultant shall develop an operational model within latest SimTraffic Version. The operational analysis will be used to micro-simulate and analyze specific roadway segments with queuing, spill back, starvation, storage blocking, and other queuing interactions, and to analyze and mitigate the conditions discovered by consultant and/or City of Santa Ana and Agencies in field reviews. D. Consultant shall develop optimized signal timings using the results from Synchro/SimTraffic, in conjunction with Tru-Traffic and recommend any changes to the signal phasing at each signalized intersection that may improve the efficiency of operations. Output of the modeling software shall not be utilized without proper QA/QC. Engineering judgment shall be utilized to determine final operational parameters. The recommended signal timing plans shall be reviewed by the City of Santa Ana and local Agency staff. 1. Consultant shall prepare, at minimum, three (3) timing plans for a typical weekday which consider the following peak periods: AM PEAK, MID-DAY PEAK, PM PEAK and one (1) timing plan for a typical Saturday/Sunday MID- DAY PEAK. Timing plans should be in Synchro, Tru-Traffic, and the preferred timing chart format of Caltrans or each local Agency. 2. Consultant shall prepare, special plans for congestion mitigation based on scenarios approved by the Agencies. 20