Costco Wholesale Specific Plan TRAFFIC IMPACT ANALYSIS REPORT Prepared for City of San Marcos 1 Civic Center Drive, San Marcos, CA 92069 Prepared by 5050 Avenida Encinas, Suite 260, Carlsbad, CA 92008 CONTACT: BOB DAVIS 760.476.9193 [email protected]; or DAVID MIZELL 760.476.9193 [email protected]. Final Draft: September 30, 2009 JN 55-100633.001 TABLE OF CONTENTS Introduction ...................................................................................................................................1 Analysis Methodology ...................................................................................................................4 Existing Conditions .......................................................................................................................7 Proposed Project .........................................................................................................................11 Existing Plus Project Conditions....................................................................................................14 Existing Plus Cumulative Conditions – Without and With Project ..................................................18 Significant Impacts and Mitigation.................................................................................................28 Caltrans ILV Analysis....................................................................................................................29 Construction Traffic Analysis.........................................................................................................31 Summary and Conclusions ...........................................................................................................33 APPENDICES Appendix A: SANTEC/ITE Guidelines Roadway Segment Capacity and LOS Criteria Appendix B: Traffic Count Data Appendix C: Existing Conditions HCM Worksheets Appendix D: SANDAG Trip Generation Rates Appendix E: Existing Plus Project Conditions HCM Worksheets Appendix F: Existing Plus Cumulative Without Project Conditions HCM Worksheets – Without SR-78 / Nordahl Road Interchange Improvements Appendix G: Existing Plus Cumulative With Project Conditions HCM Worksheets – Without SR-78 / Nordahl Road Interchange Improvements Appendix H: Existing Plus Cumulative Without Project Conditions HCM Worksheets – With SR-78 / Nordahl Road Interchange Improvements Appendix I: Existing Plus Cumulative With Project Conditions HCM Worksheets – With SR-78 / Nordahl Road Interchange Improvements Appendix J: Caltrans ILV Analysis Calculation Worksheets LIST OF EXHIBITS Exhibit 1: Regional Project Vicinity................................................................................................2 Exhibit 2: Project Site Plan............................................................................................................3 Exhibit 3: Project Study Area.........................................................................................................5 Exhibit 4: Existing Intersection Lane Geometries ..........................................................................8 Exhibit 5: Existing Conditions Traffic Volumes...............................................................................10 Exhibit 6: Project Trip Distribution .................................................................................................15 Exhibit 7: Project Trip Assignment.................................................................................................16 Exhibit 8: Existing Plus Project Conditions Traffic Volumes...........................................................17 Exhibit 9: Cumulative Project Locations ........................................................................................20 Exhibit 10: Cumulative Project Trips..............................................................................................21 Exhibit 11: Existing Plus Cumulative Without Project Conditions Traffic Volumes .........................23 Exhibit 12: Existing Plus Cumulative With Project Conditions Traffic Volumes ..............................24 Exhibit 13: Future Intersection Lane Geometries With Planned SR-78 / Nordahl Road Interchange Improvements..........................................................................................27 LIST OF TABLES Table 1: Level of Service & Delay Ranges ....................................................................................6 Table 2: Daily Level of Service Thresholds for Roadway Segments .............................................6 Table 3: Existing Peak Hour Intersection Conditions.....................................................................9 Table 4: Existing Daily Roadway Segment Conditions ..................................................................9 Table 5: Proposed Project Trip Generation – Ground-to-Plan Method ..........................................12 Table 6: Proposed Project Trip Generation – Current Plan-to-Proposed Plan Method ..................13 Table 7: Existing Plus Project Peak Hour Intersection Conditions .................................................14 Table 8: Existing Plus Project Daily Roadway Segment Conditions ..............................................18 Table 9: Cumulative Projects Trip Generation...............................................................................19 Table 10: Existing Plus Cumulative Peak Hour Intersection Conditions – Without SR-78 / Nordahl Road Interchange Improvements .....................................................................22 Table 11: Existing Plus Cumulative Daily Roadway Segment Conditions – Without SR-78 / Nordahl Road Interchange Improvements .....................................................................25 Table 12: Existing Plus Cumulative Peak Hour Intersection Conditions – With SR-78 / Nordahl Road Interchange Improvements .....................................................................26 Table 13: Existing Plus Cumulative Daily Roadway Segment Conditions – With SR-78 / Nordahl Road Interchange Improvements .....................................................................28 Table 14: ILV Methodology Performance Criteria..........................................................................29 Table 15: Caltrans ILV Analysis Summary ....................................................................................30 Table 16: Summary of Construction Truck Hauling Activity ...........................................................31 INTRODUCTION This study analyzes the forecast traffic impact of the proposed Costco Wholesale Specific Plan project, located on a 16.3-acre site that includes the existing Costco store on the west side of the Nordahl Marketplace shopping center, west of Nordahl Road and north of SR-78 in the City of San Marcos. The project consists of replacing the existing Costco warehouse building and Harley Davidson building with a new expanded Costco warehouse building, a satellite fuel station and a satellite car wash. Exhibit 1 shows the regional project vicinity. As required by the City of San Marcos, this traffic impact study has been prepared in accordance with the City’s General Plan Circulation Element and SANTEC/ITE traffic study guidelines. This traffic impact analysis includes the following study scenarios: • Existing Conditions • Existing Plus Project Conditions • Existing Plus Cumulative Conditions Without Project • Existing Plus Cumulative Conditions With Project Project Description The proposed project consists of replacing the existing 134,818 square-foot Costco warehouse building and 49,069 square-foot Harley Davidson building with a new 148,233 Costco warehouse building, a satellite fuel station with 16 pumps and a satellite car wash. The project will take access from four driveways located on Center Drive. Exhibit 2 shows the project site plan. Study Area According to SANTEC/ITE traffic study guidelines, intersections and roadway segments where 50 or more peak hour trips are forecast to be added shall be selected for inclusion in this analysis. A total of five intersections and three roadway segments were identified for inclusion in this traffic study. Based on the requirements of the SANTEC/ITE traffic study guidelines and the concurrence of City of San Marcos staff, the study area consists of the following five intersections and three roadway segments: Intersections 1) Center Drive / Avenida Ricardo 2) Nordahl Road / Center Drive 3) Nordahl Road / Montiel Road 4) Nordahl Road / SR-78 Westbound Ramps 5) Nordahl Road / SR-78 Eastbound Ramps 1 Roadway Segments 1) Center Drive, West of Nordahl Road 2) Nordahl Road, Center Drive to Montiel Road 3) Nordahl Road, Montiel Road to SR-78 The proposed project study area intersections are shown graphically in Exhibit 3. ANALYSIS METHODOLOGY In accordance with SANTEC/ITE traffic study guidelines and City of San Marcos requirements, this study analyzes the followings study scenarios: • Existing Conditions – Analysis of existing traffic count volumes, intersection geometry and existing roadway network. • Existing Plus Project – Analysis of existing traffic volumes overlaid with traffic generated by the proposed project. • Existing Plus Cumulative Conditions Without Project – Analysis of existing traffic volumes overlaid with traffic associated with approved or pending projects anticipated to be constructed within the next several years (by 2015). Analysis of existing plus cumulative conditions is evaluated both without and with the planned Nordahl Road / SR-78 interchange