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Administrative Draft Environmental Impact Report Gill Medical Center Project As shown in Table 4.19-2, the roadway segment LOS analysis method sets separate thresholds for: different types of facilities (i.e., freeways, arterials, and collectors); different number of lanes; and different area types (i.e., new versus existing). As described in City of Stockton 2018c: "Thresholds for arterials and collectors were based on Highway Capacity Manual calculations and were developed in conjunction with City staff at the time the current General Plan analysis was prepared. The arterial thresholds distinguish between roads in the existing urbanized area and those in new development areas; because arterials in new development areas can be designed to higher standards, with medians, exclusive turn lanes, and controlled access from adjacent uses, the capacities are higher than those in previously-developed areas. Thresholds for freeways were based on Highway Capacity Manual procedures relating levels of service to vehicle density ranges." As specified in City of Stockton 2018c, the "Existing" area is generally located between 1-5 and SR 99, south of Eight Mile Road. Eight Mile Road itself is considered a "New" arterial due to the lack of existing development in the area. Freeway Ramp Junction Level of Service Analysis Procedures Freeway ramp junctions are areas where freeway on-ramps merge into freeways, and where freeway off- ramps diverge from freeways. Freeway rampjunctions which are considered to be potentially affected by project-related traffic are analyzed in this draft EIR. Freeway ramp junction areas were analyzed using methods described in Chapters 12 and 13 of the Highway Capacity Manual 2010 (Transportation Research Board 2010). The Synchro software package does not analyze freeway rampjunction LOS. Therefore, the McTrans HCS+ Highway Capacity Software package was used to perform the ramp junction LOS calculations. The Highway Capacity Manual 2010 methods were used to analyze two types of freeway facilities: on- ramp junctions (merge) and off-ramp junctions (diverge). The analysis of both types of facilities involves calculating the density of vehicles on a freeway facility, expressed as passenger cars per mile per lane (pcpmpl). The LOS designation is based on the vehicle density. Table 4.19-3 presents the relationship of vehicle density to LOS for ramp junctions. Freeway ramp operating conditions are dependent on traffic volumes and the ramp characteristics. These characteristics include the length and type of acceleration and deceleration lanes, the free-flow speed of ramps, the number of lanes, grade, and the types of facilities connected to the ramps. The Highway Capacity Manual 2010 reports LOS A through E for ramps in terms of density. When the volume using the facility exceeds capacity, the V/C ratio is greater than 1, and the Highway Capacity Manual 2010 identifies the facility as overcapacity. While a density is not stated when the facility is over capacity, the freeway and ramp volumes for the facility are documented. For this draft EIR, the freeway and ramp volumes are identified for all facilities where capacity has been exceeded. Transportation 4.19-23 October 2021