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Pock Lane Residential Traffic Impact Study 4.0 EXISTING PLUS PROJECT • • This analysis scenario presents the impacts of the proposed project at the study intersections and surrounding roadway system. This scenario is identical to Existing Conditions, but with the addition of traffic from the proposed project.The proposed project would construct a total of 204 single family homes on two sites along Pock Lane. 4.1 VEHICLE MILES TRAVELED As the project is not screened out under the San Joaquin County CEQA Transportation Analysis Manual, a full VMT analysis was conducted.The technical memorandum detailing this analysis and findings is included in Appendix B and summarized below. In evaluating the existing VMT in the project area, TJKM identified a technical coding error within the SJCOG travel demand model, related to home-based school trips. School trips were being treated as work trips, with trip lengths of up to 10 miles instead of the actual average length of 1-2 miles.Although the overall impact to the model results was minimal countywide,this error does affect all traffic analysis zones (TAZ) containing schools. For the purpose of this study only, TJKM fixed this coding error for school trips and re-ran the SJCOG model for both the base year and base year plus project.As specified in the County's VMT methodology, the significance thresholds applied to projects are derived from the model baseline, including updates and revisions to the model as appropriate.Table 4 summarizes the new baseline VMT per capita and resulting thresholds for residential developments. The new baseline is 20.1 daily VMT, vs. 22.6 as included in the County's VMT guidelines. It should be noted that SJCOG is in the process of updating the model. Once updated, the County will establish new thresholds for use in future studies. Table 4: New VMT Thresholds of Significance for San Joaquin County (Residential Projects) Baseline VMT per Capita Threshold Daily VMT Threshold 23.6 15% Below Baseline 20.1 Project-Related Residential VMT With the fixed SJCOG model, both baseline and baseline plus project model runs were conducted. The results for the TAZ where the project is located are summarized in Table 5.The base year average daily VMT per resident in this TAZ is 17.9. With the addition of 204 households the average daily VMT per resident would fall to 14.6, below the applicable threshold of 20.1. Based on thresholds established by San Joaquin County, the project would have a less-than-significant impact on VMT. 4J.KM Page 123