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EXHIBIT 2 <br /> A=COM <br /> 2.0 ANALYSIS METHODOLOGY <br /> This section of the report presents the methodology used to perform the traffic analysis <br /> summarized in this report. The methodology described is consistent with the City of Santa <br /> Ana Circulation Element and the Caltrans'Guidelines for Traffic Impact Studies. <br /> Street system operating conditions are typically described in terms of "level of service." <br /> Level of service (LOS) is a report card scale used to indicate the quality of traffic flow on <br /> roadway segments and at intersection. Level of service ranges from LOS A (free flow, little <br /> congestion) to LOS F (forced flow, extreme congestion). <br /> The project limits end to the east of the 1-5 southbound on- and off-ramp to Santa Ana <br /> Boulevard, just west of Grand Avenue. However, since the limits of the proposed project <br /> improvements end just west of the 1-5 southbound on and off-ramps and since the project <br /> is not anticipated to result in increases or decreases to the volumes along Santa Ana <br /> Boulevard, detailed evaluation of Caltrans facilities (including freeway mainline and ramp- <br /> queuing analyses) is not required. <br /> 2.1 Intersection Capacity Analysis <br /> Consistent with Orange County Congestion Management Program (CMP 2009) <br /> requirements, the technique used to assess the operation of signalized intersections in <br /> Orange County is the intersection capacity utilization (ICU) method. To calculate the ICU <br /> value for an intersection, the volume of traffic using the intersection is compared with the <br /> capacity of the intersection. <br /> The ICU value is expressed as a decimal fraction (e.g., 0.752). The decimal fraction <br /> represents that portion of the hour required to provide sufficient capacity to accommodate <br /> all intersection traffic. <br /> The City of Santa Ana requires specific assumptions regarding input values to the ICU <br /> methodology. These assumptions include: <br /> • Saturation Flow Rate of 1,700 vehicles per hour per lane (vphpl) for through lanes <br /> and 1,600 vphpl for turn lanes; <br /> • Lost time factor of 5 percent; and, <br /> • Credit for "de facto" right turn lanes (locations where a right turn lane is not <br /> formally striped, but enough width is provided such that vehicles are able to <br /> conduct right turns without disrupting through traffic in a shared through-right lane). <br /> In addition to the above discussed ICU analysis method, the 2000 Highway Capacity <br /> Manual (HCM) analysis procedures have been used to analyze the intersections which <br /> are related to Caltrans facilities (ramp intersections), based on Caltrans requirements. As <br /> such, the intersection of the 1-5 southbound ramps with Santa Ana Boulevard has been <br /> analyzed using the HCM signalized method, which reports the average control delay <br /> experienced by all vehicles using the intersection. <br /> Traffic/Circulation Study—Final May 18,2012 <br /> Page 6 <br />