2017-046 - Approving Addendum Nos. 1 and 2

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Santa Ana - Garden Grove Streetcar Project Traffic Study Addendum 3.4.2 Intersection ICU Analysis Based on the HCM analysis above, the average delay increase (in seconds) for all non -streetcar movements was calculated to be 15 percent. Similarly, all intersection movements that corresponded with the streetcar movements (i.e., eastbound and westbound through movements at affected intersections) experienced an average delay decrease of 15 percent. In order to translate these delay increases/decreases into the ICU methodology, the capacity for each movement was adjusted accordingly. For example, at the intersection of Santa Ana Boulevard/Pacific Avenue, the eastbound and westbound through lane capacity (where the streetcar travels) was increased by 15 percent to reflect the reduction in delay due to transit signal priority. Conversely, all the other intersection movements (northbound/southbound and other turning movements) were effectively decreased by 15 percent to reflect the added delay experienced by non -streetcar movements during a preemption event. Table 3-8 Intersection LOS Summary - Transit Signal Priority ICU Methodology Notes: ICU - intersection capacity utilization (volume -to -capacity ratio) * Includes proposed Santa Ana Boulevard reclassification (reduction in eastbound and westbound through lanes from 4lanes to 2 lanes). 'Traffic Impact Assessment (October 2012). ' Includes capacity adjustments (increase in capacity for streetcar movements, decrease in capacity for all other movements). As shown in Table 3-8, the application of TSP (increase in capacity by 15 percent for streetcar movements with a reduction in capacity by 15 percent for all other movements) to all the affected intersections would not result in any deterioration of LOS from acceptable to unacceptable. Throughout the streetcar alignment, TSP would result in a 0.01 decrease in ICU during the both the AM and PM peak hours. Detailed ICU worksheets are provided in Appendix E. FF Previous Analysis 2035 Streetcar Conditions' Transit Signal Priority 2035 Streetcar Conditionsz Delta AM Peak PM Peak Hour Hour AM Peak Hour PM Peak Hour ID Main St Cross St ICU LOS ICU LOS ICU LOS ICU LOS 1* Santa Ana Blvd Raitt St 0.61 B 0.89 D 0.61 B 0.85 D +0.01 -0.04 2* Santa Ana Blvd Pacific Ave 0.33 A 0.58 A 0.33 A 0.55 A +0.01 -0.03 3* Santa Ana Blvd Shelton St 0.46 A 0.60 B 0.46 A 0.55 A 0 -0.05 4 Santa Ana Blvd Flower St 0.67 B 0.63 B 0.66 B 0.61 B -0.01 -0.02 5 Santa Ana Blvd Parton St 0.47 A 0.43 A 0.47 A 0.43 A 0 0 6 Santa Ana Blvd Ross St 0.61 B 0.47 A 0.59 A 0.46 A -0.02 -0.01 7 Santa Ana Blvd Bush St 0.43 A 0.55 A 0.43 A 0.55 A 0 0 8 Santa Ana Blvd French St 0.67 B 0.73 C 0.67 B 0.74 C 0 +0.01 9 Santa Ana Blvd Lacy St 0.75 C 0.57 A 0.76 C 0.57 A +0.01 0 10 Santa Ana Blvd Santiago St 0.53 A 0.64 B 0.49 A 0.65 B -0.04 +0.01 11 4" St Bush St 0.39 A 0.5 A 0.53 A 0 +0.01 12 4th St French St 0.45 A 0.4 A 0.46 A +0.01 -0.03 13 4th St Mortimer St 0.45 A 0.64= A 0.65 B -0.02 +0.01 Notes: ICU - intersection capacity utilization (volume -to -capacity ratio) * Includes proposed Santa Ana Boulevard reclassification (reduction in eastbound and westbound through lanes from 4lanes to 2 lanes). 'Traffic Impact Assessment (October 2012). ' Includes capacity adjustments (increase in capacity for streetcar movements, decrease in capacity for all other movements). As shown in Table 3-8, the application of TSP (increase in capacity by 15 percent for streetcar movements with a reduction in capacity by 15 percent for all other movements) to all the affected intersections would not result in any deterioration of LOS from acceptable to unacceptable. Throughout the streetcar alignment, TSP would result in a 0.01 decrease in ICU during the both the AM and PM peak hours. Detailed ICU worksheets are provided in Appendix E.