Appendix A Traffic Analysis Report

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TRAFFIC IMPACT ANALYSIS FAIRVIEW STREET IMPROVEMENTS FROM 9T" STREET TO 16T" STREET AND /\ JUNE 2018 BRIDGE REPLACEMENT PROJECT J" SANTA ANA, CALIFORNIA 4. The forecast growth in approach and departure volumes through 2040 No Build and Build conditions was added to the existing 2017 traffic data, resulting in "post -processed" 2040 No Build and Build link volumes. The approaches and departures along 16t" 12tn and 9tn Streets are not anticipated to experience growth as these residential neighborhoods are built out. 5. The 2040 No Build and Build turn volumes were developed using existing (2017) turn volumes and the future approach and departure volumes, based on the methodologies contained in NCHRP Report 255: Highway Traffic Data for Urbanized Area Project Planning and Design (Transportation Research Board, December 1982). A similar methodology (steps 1 through 4) was applied to develop 2040 No Build and Build roadway segment traffic volumes. For intersections that did not exist in the traffic model or had missing legs, anticipated growth (or lack thereof) from adjacent Traffic Analysis Zones (TAZs) were used to develop traffic volumes for those locations. Finally, manual adjustments were made to 2040 Build conditions to reflect the proposed change at the intersection of Fairview Street/12th Street from full access to RIRO. The 2021 No Build and Build traffic forecasts were developed based on interpolating the overall growth between existing (2017) volumes and 2040 No Build and Build forecasts. Specifically, the proportional growth from 2017 to 2021 (4 years) was scaled against the overall growth between 2017 and 2040 (23 years) to develop a growth ratio of 17.39 percent. This growth percentage was applied to the growth between 2017 and 2040 forecasts at each study intersection and roadway segment to arrive at 2021 No Build and Build traffic forecasts. Based on a review of the City's Capital Improvement Program Fiscal year: 201712018 (City of Santa Ana, May 2017) and the Circulation Element, improvements to the five study intersections outside of the restriction of the intersection of Fairview Street and 12tn Street from full -access to RIRO are not planned or included in this analysis at this time. The following presents the ability of the existing and proposed roadway facilities to accommodate 2021 and 2040 No Build and Build traffic conditions. 2021 No Build Conditions Figure 5 shows the OCTAM forecast derived 2021 No Build a.m. and p.m. peak -hour traffic volumes. As shown in Table C, the intersections along Fairview Street are anticipated to operate at acceptable LOS with the exception of the following intersections: • Fairview Street/171n Street (LOS E during the p.m. peak hour) • Fairview Street/91n Street (LOS F in both a.m. and p.m. peak hours) This represents a general worsening of intersection operations under 2021 No Build conditions. As shown in Table D, forecasted increases to daily traffic volumes along Fairview Street from existing to 2021 No Build conditions are anticipated to continue to result in unsatisfactory roadway segment LOS for the four -lane segments of Fairview Street. PAWKE1702\Traffic\doc\Traffic Analysis Report rev - Caltrans Comments.docx u06/07/18» 10