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Administrative Draft Environmental Impact Report Gill Medical Center Project Worksheets and output reports for the calculation of LOS and vehicles queues for all scenarios analyzed in the Traffic Study are presented in the Traffic Technical Appendix (See Draft EIR Appendix J). For two-way stop-sign controlled unsignalized intersections (or one-way stop-sign controlled "T" intersections), the Highway Capacity Manual method considers gap acceptance and average delay of motorists on minor streets and in turn lanes to establish LOS. Level of Service is based on the length of the delay experienced by motorists on the worst single approach, rather than the intersection as a whole. It should be noted that overall intersection average LOS at unsignalized intersections is better, often much better, than LOS on the worst single approach. Signal Warrants Procedures Traffic signal warrants are a series of standards which provide guidelines for determining if a traffic signal is appropriate. Signal warrant analyses are typically conducted at intersections of uncontrolled major streets and stop sign-controlled minor streets. If one or more signal warrants are met, signalization of the intersection may be appropriate. However, a signal should not be installed if none of the warrants are met, because installation of signals would increase delays on the previously-uncontrolled major street, resulting in an undesirable increase in overall vehicle delay at the intersection. Signalization may also increase the occurrence of certain types of accidents. Therefore, if signals are installed where signal warrants are not met, the detriment of increased accidents and overall delay may be greater than the benefit in traffic operating conditions on the single worst movement at the intersection. Signal warrants, then, provide an industry-standard basis for identifying when the adverse effect on the worst movement is substantial enough to warrant signalization. For the analysis conducted for this draft EIR, available data at unsignalized intersections are limited to a.m. and p.m. peak hour volumes. Thus, unsignalized intersections were evaluated using the Peak Hour Warrant (Warrant Number 3) from the California Department of Transportation (Caltrans) document California Manual on Uniform Traffic Control Devices (Caltrans 2014). This warrant was applied where the minor street experiences long delays in entering or crossing the major street for at least one hour of the day. The Peak Hour Warrant itself includes several components. Some of the components involve comparison of traffic volumes and vehicle delay to a series of standards. Another component involves comparison of traffic volumes to a nomograph. Even if the peak hour warrant is met, a more detailed signal warrant study is recommended before a signal is installed. The more detailed study should consider volumes during the eight highest hours of the day, volumes during the four highest hours of the day, pedestrian traffic, and accident histories. Signal warrant analysis worksheets for all stop sign-controlled intersections are presented in the Traffic Technical Appendix (see Draft EIR Appendix J). Roadway Segment Level of Service Analysis Procedures Roadway segment LOS was analyzed in the Traffic Study based on methods used in the Envision Stockton 2040 General Plan Update and Utility Master Plan Supplements Draft EIR analysis (City of Stockton 2018c). These methods set maximum daily traffic volume thresholds for each LOS designation. The thresholds are shown in Table 4.19-2. Transportation 4.19-22 October 2021