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Administrative Draft Environmental Impact Report Gill Medical Center Project Travel Forecasting As part of the General Plan update process, the City of Stockton developed a series of travel demand forecasting simulation models. In consultation with City of Stockton staff(McDowell, pers. comm.), travel forecasts used in the Traffic Study and this draft EIR are based on travel demand forecasting models developed for the City of Stockton (City of Stockton 2004a; 2018b). Travel models of the following two conditions were used to develop forecasts of future year traffic volumes for the Traffic Study: Existing Plus Approved Projects (EPAP), and 2040 Conditions with the updated General Plan. The City's travel demand models produce forecasts of daily traffic volumes. The forecasts of daily volumes generated by the City's travel model are adequate for use in the analysis of roadway segment LOS, and are used for daily volume forecasts in this draft EIR. However, the daily volumes generated by the traffic model are not, by themselves, adequate for use in the peak hour LOS analysis of study intersections. Daily traffic volumes from the travel models were used to generate growth factors. These growth factors were applied to existing peak hour intersection turning movement traffic volumes. The development of future year intersection turning movement traffic volumes requires that the turning movements at each intersection "balance". To achieve the balance, inbound traffic volumes must equal the outbound traffic volumes, and the volumes must be distributed among the various left-turn, through, and right-turn movements at each intersection. The "balancing" of future year intersection turning movement traffic volumes was conducted using methods described in the Transportation Research Board's (TRB's) National Cooperative Highway Research Program (NCHRP) Report 255, Highway Traffic Data for Urbanized Area Project Planning and Design (Transportation Research Board 1982). The NCHRP 255 method applies the desired peak hour directional volumes to the intersection turning movement volumes, using an iterative process to balance and adjust the resulting forecasts to match the desired peak hour directional volumes. 4.19.3.3 Project Impacts and Mitigation Measures The following analysis is conducted using existing background, near-term background conditions and long-term future background conditions. Future background conditions are based on the City of Stockton General Plan. Analysis of traffic operating conditions under the following seven scenarios is presented in the Traffic Impact study (Appendix J): Existing Conditions, Existing Plus Phase 1 of the GMC project, Existing Plus Buildout of the GMC project, EPAP No GMC Project Conditions, EPAP Plus GMC Project Conditions, Transportation 4.19-24 October 2021