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Home My WebLink AboutAppendix 4.15-1, Transportation Impact Analysis - Part AAppendix 4.15-1: Transportation Impact Analysis 17620.001 4834-6937-3933.3 Southline Transportation Impact Analysis Prepared for: City of South San Francisco and ICF June 2021 SF20-1089 17620.001 4834-6937-3933.3 Table of Contents 1. Project Description ................................................................................................................... 1 1.1 Transportation Demand Management Program ...................................................................................................... 6 2. Existing Conditions ................................................................................................................... 7 2.1 Environmental Setting......................................................................................................................................................... 7 2.2 Transit Facilities and Service ............................................................................................................................................. 9 2.2.1 Regional Transit and Shuttle Service ................................................................................................................. 9 2.3 Pedestrian and Bicycle Facilities ....................................................................................................................................12 3. Analysis Methodology ............................................................................................................ 16 3.1 Recent Changes to CEQA ................................................................................................................................................16 3.2 Significance Criteria ...........................................................................................................................................................17 3.2.1 Vehicle Miles Traveled (VMT) .............................................................................................................................17 3.2.2 Design Hazards ........................................................................................................................................................18 3.2.3 Emergency Vehicle Access ..................................................................................................................................18 3.2.4 Bicycle, Pedestrian, and Transit .........................................................................................................................18 3.3 Analysis Scenarios...............................................................................................................................................................19 3.3.1 Existing Conditions (Pre-COVID-19) ................................................................................................................19 3.3.2 2024 Baseline ............................................................................................................................................................19 3.3.3 2024 Baseline Plus Project Phase 1 Conditions...........................................................................................20 3.3.4 Cumulative 2040 Conditions ..............................................................................................................................20 3.3.5 Cumulative 2040 Plus Project Conditions .....................................................................................................21 3.4 Travel Demand Model Methodology .........................................................................................................................21 3.5 Trip Generation, Distribution, and Assignment ......................................................................................................21 3.5.1 Trip Generation ........................................................................................................................................................22 3.5.2 Project Vehicle Trip Distribution, and Project Vehicle Trip Assignment ...........................................27 3.6 Multimodal Analysis Methodology .............................................................................................................................38 4. Transportation Analysis .......................................................................................................... 39 4.1 Plan & Policy Consistency Review ................................................................................................................................39 4.1.1 City of South San Francisco Plans and Policies ...........................................................................................39 4.1.2 City of San Bruno Plans and Policies ...............................................................................................................42 4.1.3 Regional Plans and Policies .................................................................................................................................44 4.1.4 Policy Consistency Analysis .................................................................................................................................45 17620.001 4834-6937-3933.3 4.2 VMT Analysis ........................................................................................................................................................................46 4.3 Site Plan Analysis ................................................................................................................................................................48 4.3.1 Multimodal Analysis ...............................................................................................................................................48 4.3.2 Signal Warrant Analysis ........................................................................................................................................53 4.3.3 Phase 1 At-Grade Rail Crossing Analysis .......................................................................................................53 4.4 Offsite Transportation Analysis .....................................................................................................................................55 4.4.1 Signal Warrant Analysis ........................................................................................................................................55 4.4.2 Freeway Ramp Queuing Analysis .....................................................................................................................56 4.4.3 Transit Performance Analysis .............................................................................................................................59 4.4.4 Bicycle and Pedestrian Analysis .........................................................................................................................62 4.4.5 Emergency Vehicle Analysis ................................................................................................................................62 5. Impacts and Mitigations......................................................................................................... 63 5.1 Vehicular Traffic ...................................................................................................................................................................63 5.1.1 Vehicle Miles Traveled ..........................................................................................................................................63 5.2 Design Hazards ....................................................................................................................................................................64 5.2.1 Geometric Design Hazards ..................................................................................................................................64 5.2.2 Freeway Ramp Queuing .......................................................................................................................................64 5.2.3 At-Grade Rail Crossings ........................................................................................................................................64 5.2.4 Traffic Signal Warrant ............................................................................................................................................65 5.3 Emergency Vehicle Access ..............................................................................................................................................66 5.4 Bicycle, Pedestrian, and Transit .....................................................................................................................................67 6. Partial Circulation Network Alternative ............................................................................... 69 6.1 Plan and Policy Consistency Analysis ..........................................................................................................................69 6.2 VMT Analysis ........................................................................................................................................................................69 6.3 Site Plan Analysis ................................................................................................................................................................70 6.3.1 Design Hazards ........................................................................................................................................................70 6.3.2 Signal Warrant Analysis ........................................................................................................................................70 6.3.3 At-Grade Rail Crossing Analysis ........................................................................................................................70 6.4 Offsite Transportation Analysis .....................................................................................................................................73 6.4.1 Signal Warrant Analysis ........................................................................................................................................73 6.4.2 Freeway Ramp Queueing Analysis ...................................................................................................................73 6.4.3 Transit Performance Analysis .............................................................................................................................76 6.4.4 Bicycle and Pedestrian Analysis .........................................................................................................................76 6.4.5 Emergency Vehicle Analysis ................................................................................................................................78 17620.001 4834-6937-3933.3 6.5 Impacts and Mitigations ..................................................................................................................................................78 1.1.1 Vehicular Traffic .......................................................................................................................................................78 1.1.2 Design Hazards ........................................................................................................................................................78 1.1.3 Emergency Vehicle Access ..................................................................................................................................82 1.1.4 Bicycle, Pedestrian, and Transit .........................................................................................................................82 Appendices • Vehicle Miles Traveled Analysis for Greenhouse Gas Analysis • Traffic Operations Analysis Memorandum • Traffic Operations Reports 17620.001 4834-6937-3933.3 List of Figures Figure 1-1. Project Location & Study Area ................................................................................................................................. 3 Figure 1-2. Project Site Plan – Phase 1......................................................................................................................................... 4 Figure 1-3. Project Site Plan – Buildout ....................................................................................................................................... 5 Figure 2-1. Transit Facilities ........................................................................................................................................................... 11 Figure 2-2. Bicycle Facilities ........................................................................................................................................................... 14 Figure 2-3 Pedestrian Circulation Barriers ............................................................................................................................... 15 Figure 3-1. Vehicle Trip Distribution – Summary by County ............................................................................................ 28 Figure 3-2. Phase 1 Trip Distribution/Assignment – AM Peak Hour ............................................................................. 29 Figure 3-3. Phase 1 Trip Distribution/Assignment – PM Peak Hour ............................................................................. 30 Figure 3-4. Project Buildout Trip Distribution/Assignment – AM Peak Hour ............................................................ 31 Figure 3-5. Project Buildout Trip Distribution/Assignment – PM Peak Hour ............................................................ 32 Figure 3-6. Phase 1 Volume Difference – AM Peak Hour .................................................................................................. 33 Figure 3-7. Phase 1 Volume Difference – PM Peak Hour .................................................................................................. 34 Figure 3-8. Project Buildout Volume Difference – AM Peak Hour ................................................................................. 35 Figure 3-9. Project Buildout Volume Difference – PM Peak Hour ................................................................................. 36 Figure 3-10. Study Locations ........................................................................................................................................................ 37 Figure 4-1. South San Francisco General Plan – Proposed Streets ................................................................................ 39 Figure 4-2 Project Improvement Locations ............................................................................................................................ 50 Figure 4-3. Pedestrian Space during AM and PM Peak Hours ........................................................................................ 51 Figure 6-1. Partial Circulation Network Alternative Site Plan .......................................................................................... 71 Figure 3-1. Pedestrian Space during AM and PM Peak Hours, Project Buildout with Partial Circulation Network Alternative ................................................................................................................................................ 77 17620.001 4834-6937-3933.3 List of Tables Table 1-1. Project Land Use by Phase, Office Scenario ......................................................................................................... 2 Table 2-1. BART and SamTrans Service at the San Bruno BART Station ..................................................................... 10 Table 3-1. Person Trip Generation | Phase 1 .......................................................................................................................... 24 Table 3-2. Vehicle Trip Generation | Phase 1 .......................................................................................................................... 25 Table 3-3. Person Trip Generation | Project Buildout .......................................................................................................... 26 Table 3-4. Vehicle Trip Generation | Project Buildout ......................................................................................................... 27 Table 4-1. VMT Effects of Southline Avenue Extension within South San Francisco and San Bruno .............. 48 Table 4-2: Pedestrian Space Crowding Scale ......................................................................................................................... 49 Table 4-3: Signal Warrant Analysis ............................................................................................................................................. 53 Table 4-4. Queuing at Linden Avenue At-Grade Rail Crossing – 2040 Project Buildout ...................................... 55 Table 4-5. Existing and 2024 Weekday AM and PM Peak Hour 95th Percentile Queues..................................... 57 Table 4-6. 2040 Weekday AM and PM Peak Hour 95th Percentile Queues .............................................................. 58 Table 4-7. Average ECR Travel Times between El Camino Real and the San Bruno BART Station ................... 60 Table 4-8. Project Buildout Effect on Total Activity at San Bruno BART Station ...................................................... 61 Table 6-1. Queuing at Linden Avenue At-Grade Rail Crossing – Partial Circulation Network Alternative (2040 Project Buildout) ........................................................................................................................................... 72 Table 6-2. Queuing at Scott Street At-Grade Rail Crossing – Partial Circulation Network Alternative (2040 Project Buildout) ....................................................................................................................................................... 73 Table 4-8. Weekday AM and PM Peak Hour 95th Percentile Queues – Partial Circulation Network Alternative (Phase 1) ............................................................................................................................................... 74 Table 4-8. Cumulative Weekday AM and PM Peak Hour 95th Percentile Queues - Partial Circulation Network Alternative (Project Buildout) ............................................................................................................ 75 Appendix Table: VMT Totals for GHG Analysis ...................................................................................................................... 85 Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 1 1. Project Description This transportation impact analysis (TIA) evaluates potential transportation effects associated with the Southline Specific Plan and associated transportation infrastructure changes (“Project”). The Project would redevelop a 26.5-acre industrial site in the City of South San Francisco’s Lindenville District, adjacent to the San Bruno Bay Area Rapid Transit (BART) rail station. The Project would demolish all existing on-site uses and construct a transit-oriented office/research and development (R&D) campus with a maximum anticipated building area of 2.8 million square feet. New development would include about 2.8 million square feet of office/R&D and amenity space serving up to about 11,000 employees; approximately 5,700 parking spaces; a new east-west street connection between Sneath Lane and South Linden Avenue (referred to as “Southline Avenue”); supportive utilities and related infrastructure; and open space. The Project would also modify off-site transportation infrastructure including constructing a new intersection connecting Sneath Lane, Huntington Avenue, Maple Avenue, and Southline Avenue; extending the Centennial Way Trail to the San Bruno BART Station; providing a signalized driveway to the SamTrans Transit Center; and enhancing pedestrian access to the San Bruno BART station with new bulbouts and high visibility crosswalks. Most of this off-site transportation infrastructure is located within the City of South San Francisco; however, certain improvements, including portions of the new intersection connecting Sneath Lane, Huntington Avenue, and Maple Avenue, are located in the City of San Bruno. Development associated with the Project would be implemented under the proposed Southline Specific Plan, which would establish new land use development standards and design guidelines for development within the Specific Plan extents. A phased development process for buildout of the Specific Plan is anticipated. Phase 1 would include construction of the new Southline Avenue east-west connection road described above and the following development, most of which will be development south of the new Southline Avenue: two new office/R&D buildings with a total building area of up to approximately 613,000 square feet; the four-story, approximately 88,000-square foot amenity building (with some ground floor uses open to the public); approximately 2,754 parking spaces in a combination of below-grade parking and the eastern portion of the 9-story parking structure (located north of the new Southline Avenue); and landscaping and open space amenities. Phase 1 also includes the majority of the onsite and off-site infrastructure, roadway and pedestrian/bicycle circulation improvements. The remaining development allowed under the Specific Plan is anticipated to occur in later phases. As a transit-oriented development fully within a ½ mile walkshed of the San Bruno BART Station and SamTrans ECR bus route, the Project is presumed to have a less than significant vehicle miles traveled (VMT) impact under the City of South San Francisco’s adopted VMT Thresholds (City Council Resolution 77-2020). VMT analysis is presented in Section 4.2. Project land use and infrastructure by development Phase 1s shown in Table 1-1. The Project location and study area, Phase 1 Project site plan, and Project Buildout site plan are shown in Figure 1-1, Figure 1-2, and Figure 1-3, respectively. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 2 Table 1-1. Project Land Use by Phase, Office Scenario Scenario Phase 1 Future Phases Total at Buildout Office / R&D 612,715 2,099,085 2,711,800 Ground Floor Restaurant/Retail 16,400 0 16,400 Cafeteria (Private) 9,000 0 9,000 Fitness Center (Private) 49,000 0 49,000 Auditorium/Other (Private) 13,800 0 13,800 Total Active Land Use 700,915 2,099,085 2,800,000 Vehicle Parking Stalls 2,754 4,390 5,769 Long-Term Bicycle Parking Spaces 188 572 760 Short-Term Bicycle Parking Spaces 18 42 60 Notes: 1. The Project includes two land use scenarios – an office use and a life science use. For purposes of this analysis, the office use was analyzed to reflect a land use with a higher trip generation and more employees. 2. The ground floor restaurant/retail would be a public use. All other amenity uses would be for the private use of Project tenants. Source: ICF, 2020. CrestmoorCanyon 3101 W e s t O rangeAven ueC h e stnutAv Sout h Ai r port Boul evar dWestbor ough B lEl Cami no Real S a n B ru n o A v e n u e W e s t yW robraHSouth Linden AvenueEl Cami noRea l O rangeAvenueGrand Avenue Hunti ngtonAvNorthMcdonnell RoadC o u n tryC lubDr ive DubuqueAvUt a h A ven u eGatewayBlSneath La n e Linden AvSan Bruno Avenue EastSouthSpruceAvenueProduceAvEa stG randAv eunevA oetaM naSCher r y AvDor a do Wy Crestwood Dri veSpruce AvenueA valo n D rive MitchellAvenue ·82 %&280 %&380 14 15 17 24 31 20 26 25 27 18 19 22 23 11 16 28 13 10 87 2 3 1 4 29 30 12 6 9 21 \\Fpsf03.fpainc.local\data\Projects\2020_Projects\SF20-1089_Southline EIR\Graphics\GIS\MXD\CA_Template_LetterPortrait.mxdProject LocationFigure 1-1 Project Site New Street - Southline Avenue City Boundary Caltrain Station BART Station South Maple AvenueHun�ng t on AvenueSea Sco� St Miller A v Baden A v Bis cui t Av Ai rport Bl San Mateo AvSan Bruno South San Francisco DOWNTOWN DOWNTOWN LINDENVILLE BAYHILL TanforanShopping Center OrangeMemorial Park 0.5 mi Site Plan Figure 1-2\\Fpsf03.fpainc.local\data\Projects\2020_Projects\SF20-1089_Southline EIR\Graphics\GIS\MXD\CA_Template_LetterPortrait.mxd Project Buildout Site Plan Figure 1-3\\Fpsf03.fpainc.local\data\Projects\2020_Projects\SF20-1089_Southline EIR\Graphics\GIS\MXD\CA_Template_LetterPortrait.mxd Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 6 1.1 Transportation Demand Management Program The Project includes a transportation demand management (TDM) program designed to reduce the Project’s single-occupancy vehicle trips and parking demand consistent with the goals set forth in the City’s municipal code. The Project Sponsor has developed a Preliminary TDM program designed to achieve a 45 percent alternative mode share, consistent with City requirements for projects proposing a floor area ratio (FAR) up to 2.5 (per Chapter 20.400 of the City’s Zoning Ordinance). The preliminary TDM Plan includes a number of program measures to build upon the proposed infrastructure and on-site facilities in order to reduce single-occupancy vehicle trips to meet the required 45 percent alternative mode share target. The specific measures have not been determined as they will depend significantly on tenant needs, market and technological conditions at the time of development, and in some instances, review and approval of other agencies. Project-specific Draft TDM Plans will be required for each project phase as part of the entitlements approval, and Final TDM Plans will be provided as part of the building permit process. TDM measures may include: • Direct Access to Transit – The Project’s access improvements to the San Bruno BART Station and SamTrans Transit Center enable convenient use of BART and bus service. • Shuttle Service to Caltrain – The TDM program may provide first/last mile shuttle service for employees to the South San Francisco and/or San Bruno Caltrain stations. • Carpooling & Vanpooling Services – The TDM program would offer ride-matching services for carpools and vanpools users thorough 511.org and/or other programs; and provide reserved parking spaces for such vehicles. • Other TDM program features – The TDM program would include a range of features such as a computer app-based commute monitoring system, carshare program; guaranteed ride home program; onsite kiosks and information boards displaying transportation options available for employees; onsite showers and changing rooms; and TDM coordinator(s). As required by the City of South San Francisco Municipal Code, the Final TDM Plan would include requirements for monitoring and auditing the performance of the measures, which may be revised or amended as needed to meet the TDM performance objectives. Implementation of the Final TDM Plan would be monitored annually and adjusted accordingly, if necessary, in order to meet the required mode share targets. Leases for all tenants would include provisions regarding the mandatory TDM measures and appointment of a TDM coordinator (which may be shared among multiple tenants). Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 7 2. Existing Conditions This section describes the existing transportation and circulation setting in the vicinity of the Project site: the existing roadway network, transit network and service, pedestrian conditions, and bicycle conditions. Descriptions provided in this section reflect conditions prior to changes associated with the COVID-19 pandemic, which has resulted in reduced travel and changes to transit services. 2.1 Environmental Setting The Project site is transit-oriented, located within proximity to the San Bruno BART station (across Huntington Avenue) and the South San Francisco and San Bruno Caltrain stations (both within one mile of the Project site). The Project site is located at the northeast corner of the Sneath Avenue and Huntington Avenue intersection in the City of South San Francisco at the city’s boundary with the City of San Bruno. Under existing conditions, the Project site is not accessible from Huntington Avenue, as there is no vehicular connection to Tanforan Avenue. Instead, regional access to the site under existing conditions is provided via US-101 and I-380, with vehicles connecting to Maple Avenue, Dollar Avenue, or South Linden Avenue via surface streets. Figure 1-1 shows the Project location and the surrounding roadway system. The Project includes construction of a new street (Southline Avenue) connecting the Project site to Huntington Boulevard at the intersection with Sneath Avenue. Key local roadways in the vicinity of the Project are described below: • I-380 is an approximately 1.7-mile eight-lane freeway linking I-280 to the west and US-101 to the east. I-380 is located approximately one half-mile south of the Project site and provides the closest freeway access to the Project via El Camino Real (SR-82). Near the Project, I-380 carries about 170,000 vehicles per day. • I-280 is an eight-lane north-south freeway connection between San Francisco to San Jose that follows the western urbanized edge of the San Francisco Peninsula. At the freeway’s north and south endpoints, the route directly serves Daly City, Colma, and southwestern San Francisco neighborhoods. I-280 is located approximately 1.25 miles west of the Project site. Near the Project, I-280 carries about 200,000 vehicles per day. I-280 may be accessed via ramps at Sneath Lane and San Bruno Avenue. • US-101 is an eight-lane freeway and principle north-south roadway connection between San Francisco, San Jose, and intermediate San Francisco Peninsula cities. US-101 is located approximately one half-mile east of the Project site. Near the Project, US-101 carries about 265,000 vehicles per day. US-101 may be accessed via ramps at San Bruno Avenue, Produce Avenue/South Airport Boulevard, and Grand Avenue. • El Camino Real (SR-82) is a north-south arterial roadway and State Highway that spans the San Francisco Peninsula between San Francisco and San Jose. It has six travel lanes in the vicinity of the Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 8 Project site and connects with I-380 approximately one half mile from the Project site, providing regional vehicle access in all directions. El Camino Real carries about 45,000 vehicles per day. • Huntington Avenue is a north-south arterial and local roadway within the City of San Bruno that parallels the Caltrain corridor between Sneath Lane to the north San Felepe Avenue to the south. The San Bruno General Plan classifies the roadway as an arterial between Sneath Lane and San Mateo Avenue and as a local street south of San Mateo Avenue. Huntington Avenue East is a one- way residential street that runs alongside Huntington Avenue. • South Linden Avenue is a north-south collector roadway within the City of South San Francisco that connects Downtown South San Francisco to the north at Airport Boulevard with the Lindenville Area and the City of San Bruno to the south at San Mateo Avenue. South Linden Avenue includes an at- grade rail crossing of Caltrain. • Sneath Lane is an east-west local and arterial roadway within the City of San Bruno that connects Sweeny Ridge open space to the west and Huntington Avenue to the East. The road intersects and provides access to three major north-south regional roadways: Skyline Boulevard (SR-35), I-280, and El Camino Real (SR-82) and is one of the primary Project access roadways. The City of San Bruno General Plan classifies the roadway as an arterial east of SR-35 and a local street to the west of SR-35. • San Bruno Avenue is a four-lane east-west arterial roadway within the City of San Bruno. San Bruno Avenue provides freeway access to both I-280 and US 101. • South Maple Avenue is a two lane north-south collector street within South San Francisco that primarily provides access to destinations within the Lindenville industrial district between South Canal Street to the north and Tanforan Avenue to the south. The roadway will provide direct access to the Project site’s northern and western edges and connect with Southline Avenue and Huntington Avenue. • Dollar Avenue and Herman Street comprise a two lane north-south collector street within the City of South San Francisco and City of San Bruno, respectively, alongside the Caltrain railroad corridor and eastern edge of the Project site. Dollar Avenue and Herman Street function as the primary connection between Lindenville and the City of San Bruno to the west of the Caltrain railroad corridor, connecting to South Linden Avenue and Huntington Avenue. • Scott Street is a two lane, east-west local street in the City of San Bruno connecting Herman Street and San Mateo Avenue. Scott Street includes an at-grade rail crossing of Caltrain. • Tanforan Avenue is a two lane, local street at the border of South San Francisco and San Bruno that connects Maple Avenue and Dollar Avenue/Herman Street. Tanforan Avenue serves a mix of local residential trips and truck traffic to industrial sites in Lindenville. • Southline Avenue (South Linden Avenue Extension) is identified in the City of South San Francisco’s General Plan as a new, approximately 1,500-foot long roadway connection between Sneath Lane and South Linden Avenue. The Project includes the roadway alignment as envisioned in the General Plan. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 9 2.2 Transit Facilities and Service The Project site is directly served by the San Bruno BART station located across Huntington Avenue, and SamTrans buses at the San Bruno BART Transit Center, which is within one half mile from all buildings on the Project site. The Project is within about three-quarters of one mile of the San Bruno Caltrain station and 1.5 mile of the South San Francisco Caltrain station as well. The existing transit services are shown on Figure 2-1 and described in detail below. 2.2.1 Regional Transit and Shuttle Service The following transit services operate within the City of South San Francisco and City of San Bruno: • Bay Area Rapid Transit (BART) provides regional rail service between the East Bay, San Francisco, and San Mateo County, connecting between San Francisco International Airport and Millbrae Intermodal Station to the south, San Francisco to the north, and Oakland, Richmond, Pittsburgh/Bay Point, Dublin/Pleasanton and Fremont in the East Bay. The San Bruno Station is located adjacent to the Project site. During weekday peak commute periods, the station is served by the Richmond- Millbrae and Antioch-San Francisco International Airport lines, both of which operate on 15-minute headways with a combined headway of 7.5 minutes throughout the day. During off-peak periods, the station is served by the Antioch-San Francisco International Airport line which operates every 20 minutes. • Caltrain provides passenger rail service on the Peninsula between San Francisco and San Jose, and limited service trains to Morgan Hill and Gilroy during weekday commute periods. Caltrain operates five trains per hour, per direction during peak periods. The Peninsula Corridor Electrification Project is currently under construction to increase Caltrain service levels to six trains per hour per direction during peak periods, to provide faster, more frequent service. The Peninsula Corridor Electrification Project is anticipated to be completed by 2022. The Project site is near two Caltrain stations: ◦ South San Francisco Caltrain Station: The station is currently located approximately 1.5 mile north of the Project site at 590 Dubuque Avenue, on the east side of US-101, immediately north of East Grand Avenue. In 2021, Caltrain plans to open a relocated South San Francisco Caltrain Station near the Grand Avenue/Airport Boulevard intersection. The South San Francisco Caltrain station will be served by 23 northbound and 23 southbound local or limited trains during a typical weekday. Service is expected to increase upon completion of the Peninsula Corridor Electrification Project in 2022. ◦ San Bruno Caltrain Station: The station is located approximately three-quarter miles directly south of the Project site at the intersection of San Bruno Avenue and Huntington Avenue, within Downtown San Bruno. The station is served by 26 northbound and 26 southbound local or limited trains during a typical weekday. Service is expected to increase upon completion of the Peninsula Corridor Electrification Project in 2022. • SamTrans provides bus service in San Mateo County and serves the Project site. The SamTrans Transit Center is located at the San Bruno BART station, located adjacent to the Project site. The Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 10 SamTrans Transit Center is located less than one-half mile from all proposed buildings at the Project site and is served by routes ECR, 140, 141, and 398. A shuttle to the San Bruno Bayhill Office Park also operates during peak periods. The SamTrans service span and average peak hour frequencies are summarized in Table 2-1. Table 2-1. BART and SamTrans Service at the San Bruno BART Station Route Service Endpoints Service Span Average Peak Hour Frequency BART Red Line Richmond Station-Millbrae Station via Oakland and San Francisco 5:15 AM to 12:00 AM (NB) 6:00 AM to 1:30 AM (SB) 15 minutes BART Yellow Line Pittsburg Bay Point & Antioch Stations-San Francisco International Airport Station via Oakland and San Francisco 5:15 AM to 12:00 AM (NB) 6:00 AM to 1:30 AM (SB) 15 minutes SamTrans ECR Daly City BART / Palo Alto Transit Center via El Camino Real 5:15 AM to 1:00 AM 15 minutes SamTrans 140 Pacifica / San Francisco International Airport 6:30 AM to 12:00 AM 30 minutes SamTrans 141 Shelter Creek (San Bruno) / Airport & Linden (South San Francisco) 6:45 AM to 7:45 PM 30 minutes SamTrans 398 Redwood City Transit Center / Downtown San Francisco 5:00 AM to 11:00 PM 60 minutes Bayhill Shuttle San Bruno BART Station to Bayhill Office Park 7:00 AM to 10:00 AM, 4:00 PM to 6:40 PM 15 Minutes Notes: Table summarizes conditions prior to COVID-19. The Bayhill Shuttle is operated independently through SamTrans’ shuttle program and is open to the public. Source: Fehr & Peers; SamTrans, 2020. ! ! ! ! ! ! ! ! ! ! !!!!!! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! ! ! ! ! ! ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! ! ! !!! ! ! ! ! ! ! !!!!!CrestmoorCanyon 3101Linden AvenueC h e s tn utAv Sout h Ai rpor t Boul evar dWestbor ough B lEl Cami no Real S a n B r u n o A v e n u e W e s t Harbor WySouth Linden AvenueEl Cami noRea l O rangeAvenue GrandAvenue Hunti ngt onAvAirportBlC o u n tryC lubDriv e DubuqueAvUtah Av en u e G atewayBlS n e a t h L a n e San BrunoAve E ProduceAvEastG ra ndAv SanMateoAvenueCher r y AvDor ado WyCrestwood Dri ve SpruceAvenueA v alon D rive MitchellAvenue ·82 %&280 %&380 \\Fpsf03.fpainc.local\data\Projects\2020_Projects\SF20-1089_Southline EIR\Graphics\GIS\MXD\CA_Template_LetterPortrait.mxdExisting Transit Service Figure 2-1 SamTrans Peak Period Frequency Other Transit Service Every 15 minutes or less Every 20 - 30 minutes Greater than 30 minutes Southline Avenue BART Caltrain Free South City Shuttle Bayhill Shuttle Project Site North Mcdonnell RoadSan Mateo Av!!San Bruno South San Francisco DOWNTOWN DOWNTOWN LINDENVILLE BAYHILL TanforanShopping Center OrangeMemorial Park San Bruno 140 BH 140 292 140 292 141 141 398 398 398 ECR ECR SSF 141 South San Francisco San Bruno South San Francisco San Bruno BART CALTRAIN CALTRAIN 0.5 mi Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 12 2.3 Pedestrian and Bicycle Facilities This section reviews existing pedestrian and bicycle conditions. Pedestrian facilities include sidewalks, crosswalks, trails, and pedestrian signals. Bicycle facilities consist of separated bikeways, bicycle lanes, routes, trails, and paths, as well as bike parking, bike lockers, and showers for cyclists. Caltrans recognizes four classifications of bicycle facilities: • Class I – Shared-Use Pathway: Provides a completely separated right-of-way for the exclusive use of cyclists and pedestrians. • Class II – Bicycle Lane: Provides a striped lane for one-way travel on a street or highway. May include a “buffer” zone consisting of a striped portion of roadway between the bicycle lane and the nearest vehicle travel lane. • Class III – Bicycle Route: Provides for shared use with motor vehicle traffic; however, are often signed or include a striped bicycle lane. • Class IV – Separated Bikeway: Provides a right-of-way designated exclusively for bicycle travel adjacent to a roadway and which are protected from vehicular traffic. Types of separation include, but are not limited to, grade separation, flexible posts, inflexible physical barriers, or on-street parking. The following pedestrian and bicycle facilities are present near the Project site. Existing and proposed bicycle facilities are shown on Figure 2-2. • Sneath Lane in San Bruno has sidewalk on both sides of the street and intermittent Class II bike lanes. Bike lanes are present west of El Camino and along a two-block segment between Sea Biscuit Avenue to Huntington Avenue, but a gap occurs between El Camino Real and Sea Biscuit Avenue. • The Centennial Way Trail is a Class I shared pedestrian and bicycle pathway in South San Francisco along the BART tunnel alignment. It connects the South San Francisco BART Station with schools, parks, and neighborhoods within the City. It presently terminates adjacent to the Project site about 400 feet north of the San Bruno BART Station. • Huntington Avenue is a designated Class III bicycle route in San Bruno and South San Francisco and has sidewalks on both sides of the street. • Tanforan Avenue is a designated Class III bicycle route and has sidewalks on both sides of the street. • South Linden Avenue is a designated Class III bicycle route with sidewalks on both sides of the street. • Dollar Avenue/Herman Street is a designated Class III bicycle route and has sidewalks on the west side of the street only. • Maple Avenue is not designated as a bicycle facility and has a sidewalk along the east side of the street only alongside the Project site. Under existing conditions, the Project site is located in a mostly auto-oriented industrial and commercial area with several barriers to walking and bicycling, shown in Figure 2-3. Specifically, the following challenges to bicycle and pedestrian circulation exist: Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 13 • Access barriers to the San Bruno BART Station: When exiting the San Bruno BART Station walking or biking toward the Project site, pedestrians and bicyclists encounter Huntington Avenue, a wide multilane arterial street with narrow sidewalks and no dedicated bicycle facilities. There is no marked crosswalk directly connecting the BART Station entrance and the eastern sidewalk along Huntington Avenue, so pedestrians instead must cross two legs of the intersection to walk across the street. Both crosswalks have actuated pedestrian crossings, which add delay to pedestrians by defaulting to a “Don’t Walk” signal during a green light unless a button is pushed in advance. • Centennial Way Trail Gap: The Centennial Way Trail terminates 400 feet north of the San Bruno BART station and connects to the narrow sidewalk on the east side of Huntington Avenue. Pedestrians and bicyclists share this narrow sidewalk space, which meanders alongside Huntington Avenue and Huntington Avenue East with relatively abrupt changes in grade. • Narrow sidewalks with obstructions, limited pedestrian-scaled lighting, unmarked crosswalks, and lack of accessible curb ramps: Although sidewalks are present on most streets, pedestrians contend with indirect routes along narrow facilities that at times are inaccessible to mobility-impaired pedestrians. Areas of particular concern related to the Project include: the grade changes for the narrow eastern sidewalk along Huntington Avenue, the lack of curb ramps and marked crosswalks across Tanforan Avenue and Maple Avenue, the lack of a direct pedestrian and bicycle crossing between the Centennial Way Trail and SamTrans Transit Center at the San Bruno BART Station, and the omission of a southern crosswalk across Huntington Avenue at the San Bruno BART Station entrance. Pedestrian conditions are illustrated on Figure 2-3. • Lack of bicycle connectivity: While some bike trail and bike lane facilities are present near the Project site as shown in Figure 2-2. However, there is limited connectivity between dedicated bicycle facilities and to major destinations. For example, bike lanes along Sneath Lane do not connect to the Centennial Way Trail; the Centennial Way Trail does not connect to the San Bruno BART Station or elsewhere in San Bruno; and there is no dedicated connection between the Project site and downtown South San Francisco. Consequently, bicyclists who seek to access the Project site must share street space with cars and trucks operating on streets with posted speed limits of 25 to 30 MPH. CrestmoorCanyon 3101 W e s t O rangeAven ueC h e stnutAv Sout h Ai r port Boul evar dWestbor ough B lEl Cami no Real S a n B ru n o A v e n u e W e s t yW robraHSouth Linden AvenueEl Cami noRea l O rangeAvenueGrand Avenue Hunti ngtonAvNorthMcdonnell RoadC o u n tryC lubDr ive DubuqueAvUt a h A ven u eGatewayBlSneath La n e Linden AvSan Bruno Avenue EastSouthSpruceAvenueProduceAvEa stG randAv eunevA oetaM naSCher r y AvDor a do Wy Crestwood Dri veSpruce AvenueA valo n D rive MitchellAvenue ·82 %&280 %&38017 24 31 20 26 25 27 18 19 11 16 28 13 10 87 2 3 1 4 30 6 \\Fpsf03.fpainc.local\data\Projects\2020_Projects\SF20-1089_Southline EIR\Graphics\GIS\MXD\CA_Template_LetterPortrait.mxdBicycle FacilitiesFigure 2-2 Project Site Class II Bicycle Lane Class I Shared Path Class I Shared Path Class II Bicycle Lane Class III Bicycle Route Class III Bicycle Route Class IV Separated Bikeway New Street - Southline Avenue City Boundary Existing Bikeways Planned Bikeways San Bruno South San Francisco DOWNTOWN DOWNTOWN LINDENVILLE BAYHILL TanforanShopping Center OrangeMemorial Park South Maple AvenueHun�ng t on AvenueSea Sco� St Miller A v Baden A v Bis cui t Av Ai rport Bl San Mateo Av N:\Projects\2020_Projects\SF20-1089_Southline EIR\GraphicsPedestrian Circulation Barriers Figure 2-3 Slip-lane and indirect crosswalk configuration Crosswalk and ramp from Centennial Trail to project site needs improvement Centennial Trail transitions to narrow crosswalk Narrow sidewalk Unmarked crosswalk to BART Station Entrance Missing crosswalks Missing ramps Lack of accessible crosswalk to Centennial Way Trail Project Site Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 16 3. Analysis Methodology 3.1 Recent Changes to CEQA Senate Bill (SB) 7431, codified in Section 21099 of the California Public Resources Code, intends to better align California Environmental Quality Act (CEQA) transportation impact analysis practices and mitigation outcomes with the State’s goals to reduce greenhouse gas (GHG) emissions, encourage infill development, and improve public health through more active transportation. SB 743 creates several key statewide changes to CEQA as described below. First, SB 743 requires the Governor’s Office of Planning and Research (OPR) to establish new metrics for determining the significance of transportation impacts of Projects within transit priority areas (TPAs)2 and allows OPR to extend use of these metrics beyond TPAs. OPR selected vehicle miles traveled (VMT) as the preferred transportation impact metric and applied their discretion to require its use statewide. Second, SB 743 establishes that aesthetic and parking impacts of a residential, mixed-use residential, or employment center Projects3 on an infill site4 within a TPA shall not be considered significant impacts on the environment. Third, the new CEQA Guidelines that implement SB 743 requirements state that vehicle level of service (LOS) and similar measures related to auto delay shall not be used as the sole basis for determining the significance of transportation impacts, and that as of July 1, 2020, this requirement applies statewide. Prior to that date, lead agencies were permitted to elect to rely on VMT rather than LOS to analyze transportation impacts. Finally, SB 743 establishes a new CEQA exemption for a residential, mixed-use, or employment center Project that is a) within a transit priority area, b) consistent with a specific plan for which an EIR has been certified, and c) consistent with a Sustainable Communities Strategy (SCS). This exemption requires further review if the Project or circumstances changes significantly. 1 Full text of SB 743: https://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=201320140SB743 2 “Transit priority area” means an area within one-half mile of a major transit stop that is existing or planned, if the planned stop is scheduled to be completed within the planning horizon included in a Transportation Improvement Program adopted pursuant to Section 450.216 or 450.322 of Title 23 of the Code of Federal Regulations . (PRC 21099(a)(7)) 3 “Employment center Project” means a Project located on property zoned for commercial uses with a floor area ratio of no less than 0.75 and that is located within a transit priority area. (PRC 21099(a)(1)) 4 “Infill site” means a lot located within an urban area that has been previously developed, or on a vacant site where at least 75 percent of the perimeter of the site adjoins, or is separated only by an improved public right-of-way from, parcels that are developed with qualified urban uses. (PRC 21099(a)(4)) Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 17 The City of South San Francisco has adopted VMT thresholds (Resolution 77-2020) in accordance with OPR’s Technical Advisory on Evaluating Transportation Impacts in CEQA. 3.2 Significance Criteria The impacts of the proposed Project related to transportation would be considered significant if any of the following Standards of Significance are exceeded, in accordance with Appendix G of the CEQA Guidelines: • The Project or its effects conflict with a program, plan, ordinance or policy addressing the circulation system, including transit, roadway, bicycle and pedestrian facilities; • The Project or its effects conflicts with or is inconsistent with CEQA Guidelines section 15064.3, subdivision (b); • The Project substantially increases hazards due to a geometric design feature (e.g., sharp curves or dangerous intersections) or incompatible uses (e.g., farm equipment); or • The Project results in inadequate emergency access. Thresholds of significance used in this document are based on Appendix G criteria as well as local considerations from adopted policies by the City of South San Francisco and City of San Bruno. Neither the City of South San Francisco nor the City of San Bruno has adopted a standard set of thresholds of significance for transportation impact analyses beyond the Appendix G criteria. 3.2.1 Vehicle Miles Traveled (VMT) Pursuant to City of South San Francisco Resolution 77-2020 and CEQA Guidelines Section 15064.3, subdivision (b)(1), the following screening criteria applies to land use projects: Presumption of Less Than Significant Impact Near Transit Stations: CEQA Guideline Section 15064.3, subdivision (b)(1), states that lead agencies generally should presume that certain projects (including residential, retail, and office projects, as well as projects that are a mix of these uses) proposed within ½ mile of an existing major transit stop or an existing stop along a high quality transit corridor will have a less-than-significant impact on VMT. This presumption would not apply, however, if Project-specific or location-specific information indicates that the Project will still generate significant levels of VMT. For example, the presumption might not be appropriate if the Project: ▫ Has a Floor Area Ratio (FAR) of less than 0.75 ▫ Includes more parking for use by residents, customers, or employees of the Project than required by the jurisdiction (if the jurisdiction requires the Project to supply parking) ▫ Is inconsistent with the applicable Sustainable Communities Strategy (as determined by the lead agency, with input from the Metropolitan Planning Organization) ▫ Replaces affordable residential units with a smaller number of moderate- or high- income residential units Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 18 If a land use Project is not presumed to have a less than significant impact, the following criteria applies: • A significant impact would occur if development of the Project would generate per-employee vehicle miles traveled (VMT) greater than the City’s adopted threshold of greater than 15 percent below the regional average. For transportation infrastructure Projects (such as a street extension), the following criteria applies: • A significant impact would occur if the Project would result in a net increase in Total VMT. 3.2.2 Design Hazards 3.2.2.1 Geometric Design Hazards • A significant impact would occur if the Project substantially increases hazards to street users due to a design feature or land uses incompatible with the surrounding street network. 3.2.2.2 Vehicle Queueing at Freeway Ramps • A significant impact would occur if 95th-percentile vehicle queues were to extend beyond the available storage space and substantially exacerbate a risk of collision. 3.2.2.3 Queueing Across an At-Grade Rail Crossing • A significant impact would occur if 95th percentile vehicle queues extend beyond available storage and may substantially exacerbate risk of collisions. 3.2.2.4 Traffic Signal Warrant • A significant impact would occur if Project-related vehicle traffic at an unsignalized intersection or driveway would increase baseline volumes to meet peak hour or pedestrian volume signal warrant criteria levels, and Project-related traffic volumes may substantially increase risk of collisions. 3.2.3 Emergency Vehicle Access • A significant impact would occur if the Project results in inadequate emergency access 3.2.4 Bicycle, Pedestrian, and Transit 3.2.4.1 Consistency with Adopted Bicycle, Pedestrian, or Transit Plans & Policies • A significant impact would occur if the Project conflicts with adopted policies, plans, or programs regarding transit, bicycle, or pedestrian facilities. 3.2.4.2 Bicycle, Pedestrian, and Transit Performance & Safety • A significant impact would occur if the project were to cause a detrimental impact on the performance of transit services. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 19 • A significant impact would occur if the project were to cause a detrimental impact on the performance or safety of bicycle or pedestrian facilities. 3.3 Analysis Scenarios The impacts of the proposed Project to the surrounding transportation system were evaluated for the five scenarios listed below: • Scenario 1: Existing Conditions • Scenario 2: 2024 Baseline (No Project) • Scenario 3: 2024 Baseline Plus Project Phase 1 Conditions • Scenario 4: Cumulative 2040 Conditions • Scenario 5: Cumulative 2040 Plus Project Buildout Conditions A description of the methods used to estimate the amount of traffic and VMT generated by the proposed Project is provided below. 3.3.1 Existing Conditions (Pre-COVID-19) Existing conditions represent the baseline condition upon which Project impacts are measured. The existing condition reflects transportation conditions prior to the COVID-19 pandemic. Due to the atypical travel patterns and transit service levels during the COVID-19 pandemic, new data was not collected for this analysis. Instead, to establish a representative existing condition, this analysis utilized local traffic data collected in 2017 and 2018 and transit service levels prior to the COVID-19 pandemic (including Caltrain service levels of five trains per hour, per direction). This approach enables analysis of an observed condition and no major developments have since been completed in the immediate Project area that might substantially affect traffic patterns; however, there is inherently some uncertainty in the data’s representation of existing conditions due to its age and the unusual circumstances of the COVID-19 pandemic. 3.3.2 2024 Baseline The 2024 Baseline condition represents a near-term condition after the COVID-19 pandemic is presumed to have ended, in which travel patterns have returned to pre-COVID-19 status. The 2024 Baseline condition includes prorated local and regional growth consistent with the 2040 forecasts, reflecting the 2017/2018 conditions plus the addition of roughly one quarter of total growth between the 2017/2018 condition and 2040 forecasts. There remains substantial uncertainties around the COVID-19 pandemic’s effects on travel behavior and the duration of these effects; this approach assumes travel behavior returns to typical conditions and the effects of the pandemic are short term in nature. The 2024 Baseline also includes the completion of the Caltrain Electrification Project, a Project currently under construction that will increase Caltrain service levels to six trains per hour, per direction. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 20 3.3.3 2024 Baseline Plus Project Phase 1 Conditions The 2024 Baseline Plus Phase 1 conditions represent the 2024 condition with the addition of Phase 1 of the Project based on the anticipated Phase 1 construction schedule. Phase 1 of the Project includes several major transportation network improvements, including the construction of Southline Avenue; constructing a new intersection connecting Sneath Lane, Huntington Avenue, Maple Avenue, and Southline Avenue; providing a signalized driveway to the SamTrans Transit Center; and extension of various bicycle and pedestrian facilities, including extending the Centennial Way Trail to the San Bruno BART station and enhancing pedestrian access to the San Bruno BART station with new bulbouts and high visibility crosswalks. As such, under 2024 Baseline Plus Phase 1 conditions, traffic volumes reflect the existing traffic volumes, some redistribution of traffic to the new Southline Avenue, and traffic associated with the land uses in Phase 1 of the Project. 3.3.4 Cumulative 2040 Conditions Cumulative 2040 conditions include transportation demand resulting from reasonably foreseeable land use changes and conditions associated with planned transportation Projects. Cumulative conditions are based on forecasted land use and transportation conditions included in Plan Bay Area 2040, as represented in the C/CAG Model. Forecasts for cumulative conditions include several adjustments to reflect reasonably foreseeable Projects affecting the study area, including completion of all approved employment Projects within the City of South San Francisco as of May 2020,5 and completion of the Bayhill Specific Plan in the City of San Bruno (a plan that may be considered reasonably foreseeable even though it is not yet approved). Along the Caltrain railroad corridor, cumulative conditions include the operation of 12 trains per hour, per direction during peak periods; this service level reflects completion of the California High Speed Rail Project to operate four high speed trains per hour, per direction (as described in Plan Bay Area) as well as the Caltrain Business Plan’s adopted service vision of operating eight trains per hour, per direction during peak periods. Cumulative conditions do not assume completion of the South Linden and Scott Street grade separations since these Projects are not yet fully funded or included in the regional transportation plan. As of September 2020, both South San Francisco and San Bruno have provided direction to proceed with studying a hybrid approach for the South Linden Avenue grade crossing that involves partially raising the railway and lowering the roadway, along with closing Scott Street to vehicles and maintaining a crossing for pedestrians and bicyclists. 5 The total land use approvals for employment Projects in the City of South San Francisco exceeds Plan Bay Area forecasts, so the difference in employment growth has been added to Plan Bay Area forecasts. Projects included in this cumulative analysis include major developments such as the Cove, Gateway of the Pacific, the Oyster Point Development, and other projects in the East of 101 Area. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 21 3.3.5 Cumulative 2040 Plus Project Conditions Cumulative plus Project conditions represent the cumulative condition with the addition of the complete Project buildout to determine the extent to which the proposed Project would contribute to long-term cumulative transportation impacts. 3.4 Travel Demand Model Methodology The City/County Association of Governments of San Mateo County Travel Demand Model (C/CAG Model) was used as a basis for analyzing travel behavior, including trip distribution and vehicle miles traveled (discussed in Section 4.2). The C/CAG Model is a trip-based regional travel demand model that considers regional land use patterns, approximated highway congestion, and connecting transit service within the nine-county Bay Area region. As part of the ongoing City of South San Francisco General Plan Update study, the C/CAG model was reviewed, and updated through a series of diagnostic tests to assess the model’s performance and reasonableness, and a series of refinements were made to the model inputs for land use, roadway network and transit service within South San Francisco.6 These updates improve the C/CAG model’s effectiveness in reasonably estimating current travel patterns and changes in travel patterns in response to Project land use and transportation network changes. To further enhance the reasonableness of trip assignment from the C/CAG Model, the City of South San Francisco’s sub-area model was applied using Project trip generation and trip distribution from the C/CAG Model. The sub-area model, developed for the City of South San Francisco General Plan Update, reflects origin-destination patterns consistent with the C/CAG Model and incorporates refinements to the level of detail in the local street network. The sub-area model, developed in the Visum software platform, provides a more detailed representation of traffic circulation and operational performance of the roadway network in the vicinity of the Project and within the San Francisco and San Bruno areas. The roadway network in the sub-area model was refined to include most streets and major driveways in South San Francisco. The traffic assignment process in the sub-area model incorporates details such as signal timings, intersection lane geometries, and turning movement delays, allowing for a more realistic representation of existing traffic patterns and those associated with the Project land use and proposed street extension. 3.5 Trip Generation, Distribution, and Assignment The amount of traffic added to the roadway system by the proposed Project was estimated using a three- step process: (1) trip generation, (2) trip distribution, and (3) trip assignment. The first step, trip generation, estimates the amount of traffic that would be generated once the proposed Project was built and fully occupied. The second step, trip distribution, estimates the direction of travel to and from the Project. The 6 The updates to model were based on relevant national guidance including the 2017 Regional Transportation Plan Guidelines for Metropolitan Transportation Planning Organizations, CTC, 2017 and Travel Model Validation and Reasonableness Checking Manual, Second Edition, TMIP, FHWA, 2010. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 22 third step, trip assignment, assigns the proposed Project trips to specific street segments and intersection turning movements. The results are described below. 3.5.1 Trip Generation Project person trip and vehicle trip forecasts were developed to capture the multimodal nature of Project travel as a transit-oriented development. Person trip generation represents trips by one person in any mode of transportation, whereas vehicle trip generation represents trips by one vehicle. Vehicle trip estimates include trips associated with single occupancy vehicles, taxis, ride-hailing companies (like Uber and Lyft), carpools, and shuttles. The Project includes two land use alternatives – an office use and a life science use. For purposes of this analysis, the office use was analyzed to reflect a land use condition with an employee density – typically offices have one employee per 250 square feet, compared to one employee per 450 square feet for life science uses.7 Therefore, the Office Alternative would have a larger effect on the surrounding environment when compared to the Life Sciences Alternative. As such, this section analyzes the Office Alternative when considering project impacts under the buildout scenario. Trip generation estimates were prepared for the Phase 1 Project (701,000 square feet), inclusive of the approximately 16,400 square foot publicly-accessible ground floor uses in the amenities buildings, in addition to the Project Buildout (up to 2,800,000 square feet). As described in Section 1.1, the Project is subject to the City’s Transportation Demand Management ordinance. The Project will be required to comply with a maximum drive alone mode share of 55 percent. Under the Transportation Demand Management ordinance, the Project must comply with standard monitoring practices to enforce these mode share requirements. A Preliminary TDM Plan has been prepared for the Project, which is applicable to the entire Project site. 3.5.1.1 Office Trip Generation Office trip generation was calculated using local data from comparable sites, as further described below, based on the ITE Trip Generation Manual, 10th Edition recommendation for using local data for similar atypical developments like the proposed Project, which is very large in scale, adjacent to high frequency transit service, has a reduced parking supply, and is subject to stringent transportation demand management requirements. Based on the ITE recommendation, this analysis estimates person trip and vehicle trip rates based on observed counts and mode share surveys for comparable high intensity technology office uses in Downtown Redwood City near the Redwood City Caltrain Station, as analyzed in the Redwood City Moves Transportation Plan. Based on a review of comparable trip generation and mode share data for other transit-oriented office sites located in San Francisco, Oakland, and San Mateo, the Downtown Redwood City location was selected based on land use, transit, and TDM characteristics that 7 San Jose Market Overview and Employment Lands Analysis, City of San Jose, 2016. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 23 most closely resemble the Project. These person trip and vehicle trip rates from the Downtown Redwood City data were adjusted to reflect the Project’s mode share requirements consistent with the City of South San Francisco’s TDM ordinance – a maximum peak period drive alone rate of 55 percent including single- occupancy vehicles and single-passenger trips via ride-hailing companies or taxis, as compared to an observed peak period drive-alone rate of 50 percent in the downtown Redwood City surveys.8 Person trip generation for non-auto modes was based on transit, carpool, and active transportation data from South San Francisco TDM surveys and the proximity of the Project to transit services and active transportation facilities. An estimated 23 percent of peak hour trips would occur via BART, 10 percent via Caltrain, eight percent via Carpool, two percent via SamTrans buses, and two percent via bicycling. Trips via BART and SamTrans would require walking from the Project to the San Bruno BART Station or SamTrans bus transit center, while trips via Caltrain would connect via first/last mile shuttles or via biking. 3.5.1.2 Amenity Uses Trip generation for the Project’s publicly accessible restaurant/retail uses were estimated using the High Turnover Restaurant classification from the Trip Generation Manual, 10th Edition. Since the publicly accessible amenities are generally expected to draw pedestrian trips from elsewhere within the Project site and adjacent areas, the High Turnover Restaurant classification provides a conservative assessment of vehicle trips that is typically more reflective of a more automobile-oriented use. Amenity uses accessible only to tenants of the Project such as an employee cafeteria, fitness center, basketball court, auditorium would not generate external vehicle trips, but would generate employee- related person trips for individuals employed at these services. Trip generation for these internal private amenities was estimated at about one quarter of office rates based on anticipated employee densities and mix of staffed and unstaffed uses9. Trip generation for the public and private amenity uses were included in both the Phase 1 Project and Project Buildout. 3.5.1.3 Trip Internalization In mixed use developments, some trips between different land uses are “internalized” onsite – occurring by walking rather than driving elsewhere. The project proposes to include a mix of office and amenity uses that would facilitate some internalization (such as an office employee walking to a fitness center, cafeteria, and café or retail space). Internalization rates of 3 percent (AM peak hour) and 2 percent (PM peak hour) were applied to all vehicle trips during the respective peak hours, based on the Mixed-Use Trip Generation Model 8 City of South San Francisco’s TDM ordinance establishes required alternative mode share of 45 percent based on Project floor area ratio. 9 Based on the San Mateo County Linkage Fee Nexus Study, restaurant and service uses typically have half of the employee density of office uses. About half of the Project amenity spaces were identified to be actively staffed restaurant and service uses; therefore, the employee density and trip generation was assumed to be one-quarter of office uses. Office trip generation typically reflect mostly trips by employees, so the ratio of amenity density to office density was applied to trip generation to determine amenity trip generation rates. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 24 (MXD) + Model, a weighted average of the U.S. Environmental Protection Agency’s MXD and the National Cooperative Highway Research Program’s 684 methodology. 3.5.1.4 Credit for Existing Trip Generation The project’s net change in the number of vehicle trips was calculated to reflect the estimated number of vehicle trips occurring at the Specific Plan area under existing conditions. Because of the atypical travel patterns associated with the COVID-19 shelter-in-place order, driveway counts at existing uses were not conducted. Instead, trip generation for existing uses within the Specific Plan area was estimated based on land use characteristics and Trip Generation Manual recommendations. Existing land uses include approximately 344,000 square feet of light industrial and office uses, about 85 percent of which is occupied. All of the existing land uses would be demolished as part of Phase 1; therefore, both Phase 1 and project buildout trip generation include the full trip credit associated with existing land uses. In total, existing uses generate an estimated 1,504 daily vehicle trips, including 171 AM peak-hour vehicle trips and 150 PM peak- hour vehicle trips. 3.5.1.5 Trip Generation Results Phase 1 of the Project would generate approximately 7,930 daily person trips and 3,954 daily vehicle trips. These totals include 1,043 AM peak hour person trips, 485 net new AM peak hour vehicle trips, 950 PM peak hour person trips, and 455 net new PM peak hour vehicle trips. Table 3-1 and Table 3-2 show person trip and vehicle trip generation estimates for Phase 1, respectively. Table 3-1. Person Trip Generation | Phase 1 Mode Mode Share AM Peak Hour PM Peak Hour Daily Drive Alone 55% 499 447 3,837 Carpool 8% 73 65 550 BART 23% 209 187 1,281 Caltrain1 10% 91 81 557 SamTrans 2% 18 16 111 Walk/Bike2 2% 18 16 111 Total Person Trips Monitored by TDM Ordinance 100% 908 812 6,448 Person Trips, Public Amenity Visitors - 135 138 1,482 Total Person Trips - 1,043 950 7,930 Notes: 1. Based on travel demand data from high intensity tech office mode share and person trip generation surveys from Downtown Redwood City near the Redwood City Caltrain Station as well as requirements from City of South San Francisco TDM Ordinance. 2. Mode share estimates based on City of South San Francisco TDM Surveys and analysis based on local context. Source: Fehr & Peers, 2020. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 25 Table 3-2. Vehicle Trip Generation | Phase 1 Land Use Size (KSF) AM Peak Hour PM Peak Hour Daily Rate (per KSF) In Out Total Rate (per KSF) In Out Total Rate (per KSF) Total Office1 613 0.81 464 35 499 0.73 58 387 445 6.16 3,774 Private Amenities2 72 0.23 15 1 16 0.20 2 13 15 1.72 124 Public Amenities3 16 9.94 87 72 159 9.77 97 59 156 115 1,840 Internalization Adjustment (3% AM / 2% PM) -15 -3 -18 -3 -8 -11 -280 Project Trips 551 105 656 154 451 605 5,458 Existing Office4 11 ITE Equation -10 -2 -12 ITE Equation -2 -12 -14 9.74 -125 Existing Light Industrial5 278 ITE Equation -140 -19 -159 ITE Equation -18 -118 -136 4.96 -1,379 Net New Project Trips 401 84 485 134 321 455 3,954 Notes: 1. Based on travel demand data from high intensity tech office mode share and vehicle trip generation surveys from Downtown Redwood City near the Redwood City Caltrain Station as well as requirements from City of South San Francisco TDM Ordinance. Values rounded in table. 2. Includes external trips associated with employee commutes and deliveries only, assumed to be 72 percent less than the office trip generation rate based upon expected uses and employee densities. 3. Source: ITE 932 High Turnover Restaurant, Institute of Transportation Engineers. Trip Generation Manual, 10th ed. Values rounded in table. 4. Source: ITE 710, General Office Building, Institute of Transportation Engineers. Trip Generation Manual, 10th ed. Fitted curve equation used for individual land uses. Includes occupied spaces only as of March 2020. Values rounded in table. All existing uses are assumed to be removed with the Phase 1 Project. 5. Source: ITE 110, General Light Industrial, Institute of Transportation Engineers. Trip Generation Manual, 10th ed. Fitted curve equation used for individual land uses. Includes occupied spaces only as of March 2020. Values rounded in table. All existing uses are assumed to be removed with the Phase 1 Project. Source: Fehr & Peers, 2020. The Project Buildout would generate approximately 28,461 daily person trips and 16,876 vehicle trips. These totals include 3,918 AM peak hour person trips, 2,150 net new AM peak hour vehicle trips, 3,528 PM peak hour person trips, and 1,952 PM peak hour vehicle trips. Table 3-3 and Table 3-4 show person trip and vehicle trip generation estimates for the Project Buildout respectively. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 26 Table 3-3. Person Trip Generation | Project Buildout Mode Mode Share AM Peak Hour PM Peak Hour Daily Drive Alone 55% 2,105 1,879 15,984 Carpool 8% 306 273 2,317 BART 23% 880 786 5,394 Caltrain1 10% 383 342 2,345 SamTrans 2% 77 68 469 Walk/Bike2 2% 77 68 469 Total Person Trips Monitored by TDM Ordinance 100% 3,828 3,416 26,978 Person Trips, Public Amenity Visitors - 90 112 1,483 Total Person Trips - 3,918 3,528 28,461 Notes: 1. Based on travel demand data from high intensity tech office mode share and person trip generation surveys from Downtown Redwood City near the Redwood City Caltrain Station as well as requirements from City of South San Francisco TDM Ordinance. 2. Mode share estimates based on City of South San Francisco TDM Surveys and assignment to transit providers based on local context and expected travel patterns. Source: Fehr & Peers, 2020. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 27 Table 3-4. Vehicle Trip Generation | Project Buildout Land Use Size (KSF) AM Peak Hour PM Peak Hour Daily Rate (per KSF) In Out Total Rate (per KSF) In Out Total Rate (per KSF) Total Office1 2,712 0.81 2,053 155 2,208 0.73 256 1,713 1,969 6.16 16,696 Private Amenities2 72 0.23 15 1 16 0.20 2 13 15 1.72 124 Public Amenities3 16 9.94 87 72 159 9.77 97 59 156 115 1,840 Internalization Adjustment (3% AM / 2% PM) -56 -6 -62 -6 -32 -38 -280 Project Trips 2,099 222 2,321 349 1,753 2,102 18,380 Existing Office4 11 ITE Equation -10 -2 -12 ITE Equation -2 -12 -14 9.74 -125 Existing Light Industrial5 278 ITE Equation -140 -19 -159 ITE Equation -18 -118 -136 4.96 -1,379 Net New Project Trips 1,949 201 2,150 329 1,623 1,952 16,876 Notes: 1. Based on travel demand data from high intensity tech office mode share and vehicle trip generation surveys from Downtown Redwood City near the Redwood City Caltrain Station as well as requirements from City of South San Francisco TDM Ordinance. Values rounded in table. 2. Includes external trips associated with employee commutes and deliveries only, assumed to be 72 percent less than the office trip generation rate based upon expected uses and employee densities. 3. Source: ITE 932 High Turnover Restaurant, Institute of Transportation Engineers. Trip Generation Manual, 10th ed. Values rounded in table. 4. Source: ITE 710, General Office Building, Institute of Transportation Engineers. Trip Generation Manual, 10th ed. Fitted curve equation used for individual land uses. Includes occupied spaces only as of March 2020. Values rounded in table. 5. Source: ITE 110, General Light Industrial, Institute of Transportation Engineers. Trip Generation Manual, 10th ed. Fitted curve equation used for individual land uses. Includes occupied spaces only as of March 2020. Values rounded in table. Source: Fehr & Peers, 2020. 3.5.2 Project Vehicle Trip Distribution, and Project Vehicle Trip Assignment Figure 3-1 displays vehicle trip distribution by county based on the C/CAG Model. Approximately 65 percent of vehicle trips would travel between the Project and other locations in San Mateo County. About 21 percent of trips would travel between the Project and San Francisco County. The remainder of trips would be split between Alameda County, Santa Clara County, and elsewhere in the East Bay and North Bay. This summary does not include trip distribution associated with non-auto trips. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 28 Figure 3-1. Vehicle Trip Distribution – Summary by County Figure 3-2 through Figure 3-5 illustrate Phase 1 and Project Buildout trip distribution and assignment based on the City’s sub-area model, depicting street segments with greater than 25 Project-generated trips. Vehicle trip distribution from the Project is shown in green, while volumes assigned to individual streets are illustrated proportionally in blue. The Project’s location and access to multiple freeway ramps would result in drivers using several different routes to access US-101, I-380, and I-280. Because 2040 freeway conditions are projected to be highly congested, some Project trips may travel somewhat longer distances via parallel corridors such as El Camino Real or Junipero Serra Boulevard. Approximately 56 percent of Project- generated trips would travel via San Bruno, and 44 percent via South San Francisco. Figure 3-6 through Figure 3-9 illustrate the total difference in volumes associated with the Phase 1 Project and Project Buildout (the Phase 1 and Project Buildout trip assignment plus the rerouting of trips associated with the new street connection). Change in trips is illustrated proportionally with increases shown in red and decreases shown in green. By adding the Southline Avenue connection between Sneath Lane/Huntington Avenue and South Linden Avenue, the Project would shift vehicle trips from other routes, resulting in a net decrease in traffic volumes on parallel routes like Spruce Avenue and Scott Street. 2024 conditions generally mirror those shown in 2040 with lower traffic volumes associated with Phase 1. The vehicle trip assignment served as the basis for selecting study locations for freeway ramps (Figure 3-10) as well as simulation of local transportation conditions, described in the following section. San Mateo County, 65% San Francisco County, 21% Alameda County, 4% Santa Clara County , 4%Other, 5% © OpenStreetMap contributors© OpenStreetMap contributors© OpenStreetMap contributors 54 5 5 5434343434345 5 325555 3055 5 5 322077 5 6 49 60 30 29 6 8 77 49 49 49 49 17 1 7 77 31 7 7 6 0 6 4 6 7 37 36 6 0 60 3 13737 5 6 4848 48 49 6 8 5 6 30 40 38 3 7 2 8 37 3 2 20 32 32 3 2 32 4031 30 32 3221573838257577 2 518 7 7 7 7 2 6 5 2 4 6 45 212341 20187545 37232327252525252643372339 16 16 3839 322 4 2 4 2 4 20201442 675 6 3 1 7 8565 6 2 0 4 1261261255615 179 626 5 05 63 1 22 49497 6 4 24747 18251517 15152 2 2 3 252520 2428 27151 818421517 1715 242419 Volume flow bundle PrT [veh] (AP)0 67 133 267 Southline E+Phase 1 Phase 1 Trip Distribution - AM Peak Hour Project Site \\fpsf03\Data\Projects\2020_Projects\SF20-1089_Southline EIR\Analysis\Model\PlotsSouthline - Phase 1 Trip Distribution - AM Peak Hour Figure 3-2 30 70 150 270 20% 10% 20% 50% XX%Trip Distribution © OpenStreetMap contributors© OpenStreetMap contributors© OpenStreetMap contributors302 9 31 2 2 2 8 2 9 2828 3 0 2822 2 2 2 52 521 21 23252 597 77 96 2 5 2 0 97 77 76 76 76 84 31 97 9 6 9 6 97 96 96 3 1 202525757676 76 2 4 25 15191 9 1515151545 30 28 28 5050 2 36958605051 248339 2 4 3 6 3 7 6 8 2 42 5 25 388325 222424252522226161 61 61 162991622 6 1 6 25 1 7 1 7 7 325 2 6969593 472 876 4 547164545 6 5 2 9 4 4 2 3 5151511 64929174949 16 15 Volume flow bundle PrT [veh] (AP)0 40 81 162 Southline E+Phase 1 Phase 1 Trip Distribution - 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Base_2015_2019LU\VOL_1HR_PM0248497993<= 0.00> 0 Southline E+Phase 1 Volume Difference - PM Peak Hour Project Site Decrease Increase Volume - veh/hrChange in Volume\\fpsf03\Data\Projects\2020_Projects\SF20-1089_Southline EIR\Analysis\Model\PlotsSouthline - Existing Plus Phase 1 Volume Difference - PM Peak Hour Figure 3-7 100 250 500 1000 © OpenStreetMap contributors© OpenStreetMap contributors© OpenStreetMap contributors 170168802 2 8 202 -53-27-70-8 0322 3 1 21236 -51-6932 -67 101 33 -42 190155159221227263 8-523350 2 5 7 -26-51-54 15136 343740189214 172 1 5 4 6758327 39 3 1 12186121 1 2 1 -36 4 9 56 56 -2727 3 2 7 45-9166-2812412448 6631-3 9 39 4 9-27-2727 -39-3 6 35 -64 64 3 3 83 59 1 3 5 1 1 6 110 1 1 3 9 3 94 116135 8 2 2 6 8 -1 5 7 8 8 64 82 52 53 27 52 28 47 34 6364 -1 02 4 5 64 6 2 52 45 2 851 60 165 160 61 59 45-1 02 -1 5 8 87 44 120 - 62 1 6 1 4748 55 52 28 2 8 437 1133 5 35 119 123 123 110 596037 105-271 5 432-282 9 4 130 4 127 4 028426969 42 5626127 41595383-26265 3 535328 55 37669 7 939338 5151512669 39 152 31 174-2728 1 2 9 33 32 2931404263669241 392629 92521 2 4 -7 1 12226-10177-100-15939 -89-1922927 41 30 53 50 36181607292-157115 1 8 5 4 1 -1 6 41 0 611 0 -1 6 0 4 6 3 4 3 86 6 -1 0 6 -11457 3162236-3 6 -344011049 -122 119607682-35-26-3410541186181353836182401061187751 63 2536 35 13839643628828 32 31 27 28 32 33 34436538312636 40 39 64 172 64 32 48 73 3 4 38 -38 62 17835 49 33 41 41 37 37 2709731075 6 1 1 31 2 7 2 0 0 3 3 3 3 8 9 -8 3 -43 -4 3 -42 -40-4 3 -2 9 2 8 4-1 4 0 -158 20020 0-1 5 7460461955028 361 0 5-5 0 2919638604730 34323 2 2938-3921 1 119-53 3938 -2 6 3737314926 27 2 9 449 2 31 2 72634334536 44 -5 7 3 62 7 4 83 0 3 2 8 2 70 48 49140107-8 9 -50485232363 5 485326266671 30 -50-474262 48 6 4 6 33140 39 27 28 627454 4 3-84273 0 51 50 31 302929 32 32 40-533355 6250 42-4734 35 34 522 9 433241 35 35 34 100 -43-4850 31 3427504982 292866 2 9 34 43 403839Version comparison - Southline 2040 No Project\VOL_1HR_AM03466921383<= 0.00> 0 Southline 2040 Buildout Volume Difference - AM Peak Hour\\fpsf03\Data\Projects\2020_Projects\SF20-1089_Southline EIR\Analysis\Model\PlotsSouthlineProject Volume Difference - AM Peak Hour Figure 3-8 Decrease Increase 350 700 1400 Volume - veh/hrChange in Volume Project Site © OpenStreetMap contributors© OpenStreetMap contributors© OpenStreetMap contributors3012567 879946130 941 6 1 7 9 -32-51 1 5 8 7912 3 547 08578 44 90 39401171042 8 -41-33-3 7 120 10554 5462 27161 22 63 5 94576 2 -3 2 -32 43 5886 8610431 2619143 39 33 6 4 949 4 1 101 2 5 136 136 72 1 1 7 89 8 9 89 8 0 1 177 0 3 1 2 9 9 11 3 136 99 94 90 62 44 135 4 9 113 1 3 8 30 36 9 3 8 1 101 98 1 3 7 136 49101100 8 6 1 4 2 1 1 0 1 2 5 114115 94 89 7 73 0 8 1 2 5 1 1 0 91 90 30107 107 30 328 8 9228 51-8939 964096 54-7727342 656 33 -34494 9 323 4 5 0 393 839 38 2829 46393994 342638313 4 3 4 2 7 3 9 3 9 3 9 69 37105 1 1 2 1 2 8 14714331 88 47 118 120 55-7653423333 33401 1 5 29337072102-311021 0 6 -28 -4 4 9436 374249-98-153-203-146-18926 293231 1608536752888-114 7 7-1 1 9 -1 1 5 8 2 4 325 2 4-1 3 4 4 3 37-140 123 179-3 9 -35 292943-5356-140 37 15427 344158-34-306315482851581701618643638427153473 335 7 2 2952413884024541-50 45334071230283-44 96 91 5 9 5568 44 38 164693331 47 61 -41 33 33 3 84283527 3 7 1 2 8 -1 63 3 1 3 1 2 845 30 3 7 -28-472 8 -3 32 2 1107-186-1 7 71 1 7135119637 27 5 01656803043738 -59-293426274130-74101 2 6 23043 0 -2743362 846 41 2 5 6 26 2 49 -6 51 7 3 34 23 89 6 2627 14794-5 3-4632 -413642283434374046 -53 -44-9441 2834 30 55 31 5228 3 75050-403 4 34 292929 30 382 8 34 31 -82-9448 49 39303130 -38 -57-70-8834 34 3231 34 26 35 32 29277038 33 36 3452 39-27 Version comparison - Southline 2040 No Project\VOL_1HR_PM03737461492<= 0.00> 0 Southline 2040 Buildout Volume Difference - PM Peak Hour\\fpsf03\Data\Projects\2020_Projects\SF20-1089_Southline EIR\Analysis\Model\PlotsSouthlineProject Volume Difference - PM Peak Hour Figure 3-9 Decrease Increase 350 700 1400 Volume - veh/hrChange in Volume Project SiteProject Site CrestmoorCanyon 3101 W e s t O rangeAven ueC h e stnutAv South A irport Bou le va rd Westbor ough B lEl Cam ino Rea l San Bru n o A v e n u e W e s t yW robraHSouth Linden AvenueEl Cami noRea l O rangeAvenueGrand Avenue Hunti ngtonAvNorthMcdonnell RoadC o u n tryC lubDr ive DubuqueAvUtah Av e n u eGatewayBlSneat h L a n e Linden AvSan Bruno Avenue EastSouthSpruceAvenueProduceAvEa stG randAv eunevA oetaM naSCherry AvDor ado WyCrestwood DriveSpruce AvenueAva lo n Drive MitchellAvenue ·82 %&280 %&380 14 15 17 24 31 20 26 25 27 18 19 22 23 11 16 28 13 10 87 2 3 1 4 29 30 12 6 9 21 \\Fpsf03.fpainc.local\data\Projects\2020_Projects\SF20-1089_Southline EIR\Graphics\GIS\MXD\CA_Template_LetterPortrait.mxdFigure 3-10Study Locations Project Site New Street - Southline Avenue City Boundary Caltrain Station BART Station Microsimulation Network Freeway Intersections South Maple AvenueHun�ng t on AvenueSea Sco� St Miller A v Baden A v Bis cui t Av Ai rport Bl San Mateo AvSan Bruno South San Francisco DOWNTOWN DOWNTOWN LINDENVILLE BAYHILL TanforanShopping Center OrangeMemorial Park ! ! ! ! ! ! ! ! ! ! 1 2 3 4 5 6 7 8 9 10 0.5 mi ! Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 38 3.6 Multimodal Analysis Methodology The Vissim software program was used as the basis for evaluating the congestion and multimodal traffic conditions around the Project. Vissim analyzes traffic by simulating and capturing the interactions between individual cars, trucks, buses, pedestrians and bicycles. In addition to vehicular LOS, Vissim enables evaluation of vehicle queuing, transit and emergency vehicle delays, pedestrian and bicycle delays, and pedestrian density (via the Viswalk module). When analyzing new and modified traffic signals in the Project, traffic signal timing was optimized to balance minimizing conflicts between pedestrians and vehicles and reducing delay for all users. Synchro and SimTraffic software were used to evaluate vehicle queueing at freeway ramps. Synchro was used as the primary analysis tool to identify potentially congested locations, while SimTraffic was used to refine the queueing analysis at congested locations. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 39 4. Transportation Analysis This section includes analysis and findings of the Project’s environmental effects on transportation services and facilities related to walking, biking, driving, and riding transit. Topics covered include: • Plan & Policy Consistency Review • VMT Analysis • Trip Generation, Distribution, and Assignment • Site Plan Analysis • Offsite Analysis 4.1 Plan & Policy Consistency Review This section reviews the Project’s consistency with adopted plans and policies by local and regional jurisdictions. 4.1.1 City of South San Francisco Plans and Policies 4.1.1.1 General Plan Policies The Project site is located within the Lindenville Planning Sub-Area under the General Plan. The General Plan includes a number of policies that encourage redevelopment and infrastructure improvements in the Lindenville Planning Sub-Area, such as providing better connectivity to San Bruno BART station, including via an extension of Sneath Lane through the Project site. The General Plan contemplates that a new east- west street that would bisect the Project site and create a connection between Sneath Lane and South Linden Avenue to serve as the gateway between Downtown and San Bruno BART Station, as shown in Figure 4-1. Figure 4-1. South San Francisco General Plan (1999) – Proposed Streets Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 40 The following City of South San Francisco General Plan policies relate to the Project and walking, biking, and transit.10 A new 2040 General Plan (Shape SSF) is currently being prepared by the City, but the City has not yet adopted new policies. • 3.2-G-2 Develop new streets and through connections to facilitate truck movement; improve access to U.S. 101, and provide better connectivity between the proposed San Bruno BART station and Downtown. • 3.2-G-3 Enhance the appearance of the area by undertaking streetscape and other improvements. • 3.2-I-14 Provide new street extensions in Lindenville as outlined in Chapter 4: Transportation.. including extension of South Linden Avenue to the San Bruno BART station • 4.2-G-2 Improve connections between different parts of the city. • 4.2-G-8 Use the Bicycle Master Plan to identify, schedule, and implement roadway improvements that enhance bicycle access. • 4.2-G-9 Use the Pedestrian Master Plan to identify, schedule, and implement roadway improvements that enhance pedestrian access. • 4.2-G-10 Make efficient use of existing transportation facilities and, through the arrangement of land uses, improved alternate modes, and enhanced integration of various transportation systems serving South San Francisco, strive to reduce the total vehicle-miles traveled. • 4.2-G-13 Integrate Complete Streets infrastructure and design features into street design and construction to create safe and inviting environments for people to walk, bicycle, and use public transportation. • 4.2-I-2 Undertake street improvements [including the] South Linden Avenue extension to Sneath Lane. • 4.2-I-10 In planning, designing, and constructing Complete Streets: ◦ Include infrastructure that promotes a safe means of travel for all users along the right of way, such as sidewalks, shared use paths, bicycle lanes, and paved shoulders. ◦ Include infrastructure that facilitates safe crossing of the right of way, such as accessible curb ramps, crosswalks, refuge islands, and pedestrian signals; such infrastructure must meet the needs of people with different types of disabilities and people of different ages. ◦ Ensure that sidewalks, crosswalks, public transportation stops and facilities, and other aspects of the transportation right of way are compliant with the Americans with Disabilities Act and meet the needs of people with different types of disabilities, including mobility impairments, vision impairments, hearing impairments, and others. Ensure that the South San Francisco ADA Transition Plan includes a prioritization method for enhancements and revise if necessary. 10 The City of South San Francisco General Plan includes policies related to automobile LOS for certain locations, however, General Plan Policy 4.2-G-17 exempts development within one-quarter mile of a Caltrain or BART station, or a City-designated ferry terminal, from LOS standards, which applies to the Project. Moreover, under SB 743, LOS or similar measures of traffic congestion are no longer considered a significant impact under CEQA, Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 41 ◦ Prioritize incorporation of street design features and techniques that promote safe and comfortable travel by pedestrians, bicyclists, and users of public transportation, such as traffic calming circles, additional traffic calming mechanisms, narrow vehicle lanes, raised medians, dedicated transit lanes, transit priority signalization, transit bulb outs, road diets, high street connectivity, and physical buffers and separations between vehicular traffic and other users. ◦ Ensure use of additional features that improve the comfort and safety of users: Provide pedestrian-oriented signs, pedestrian-scale lighting, benches and other street furniture, bicycle parking facilities, and comfortable and attractive public transportation stops and facilities. Encourage street trees, landscaping, and planting strips, including native plants where possible, in order to buffer traffic noise and protect and shade pedestrians and bicyclists. Reduce surface water runoff by reducing the amount of impervious surfaces on the streets. • 4.2-I-11 In all street projects, include infrastructure that improves transportation options for pedestrians, bicyclists, and users of public transportation of all ages and abilities. ◦ Ensure that this infrastructure is included in planning, design, approval, construction, operations, and maintenance phases of street projects. ◦ Incorporate this infrastructure into all construction, reconstruction, retrofit, maintenance, alteration, and repair of streets, bridges, and other portions of the transportation network. • 4.3-I-14 Undertake a program to improve pedestrian connections between the rail stations—South San Francisco and San Bruno BART stations and the Caltrain Station—and the surroundings. Components of the program should include: ◦ Installing handicapped ramps at all intersections as street improvements are being installed; ◦ Constructing wide sidewalks where feasible to accommodate increased pedestrian use; • Providing intersection “bulbing” to reduce walking distances across streets in Downtown, across El Camino Real and Mission Road, and other high use areas; ◦ Continuing with the City’s current policy of providing pedestrian facilities at all signalized intersections; ◦ Providing landscaping that encourages pedestrian use 4.1.1.2 Bicycle and Pedestrian Master Plans The City of South San Francisco’s Bicycle Master Plan and Pedestrian Master Plan identify improvements to provide safer walking and biking to make active transportation an integral part of the City’s transportation system. Near the Project site, the Bicycle Master Plan identifies Class III bicycle routes on South Linden Avenue and Dollar Avenue. Both plans are currently being updated in the Active South City Bicycle and Pedestrian Master Plan in connection with the City’s General Plan Update in progress (Shape SSF), which has not yet been adopted. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 42 4.1.1.3 South San Francisco Transportation Demand Management Ordinance The City’s Transportation Demand Management (TDM) Ordinance, which is specified in Title 20 of the City’s Municipal Code in Chapter 20.400, Transportation Demand Management, seeks to reduce the amount of traffic generated by nonresidential development and minimize drive-alone commute trips. The TDM ordinance establishes a performance target for minimum alternative mode share for all nonresidential projects resulting in more than 100 average daily trips and identifies higher thresholds for projects that will be developed at increased intensity. For the Project, the minimum alternative mode share is 45 percent, based on the requested FAR. Per the TDM ordinance, all projects are required to submit annual mode share surveys. Projects seeking a FAR bonus are also required to submit triennial reports assessing project compliance with the required alternative mode share target. Where targets are not achieved, the report must include program modification recommendations and City officials may impose administrative penalties should subsequent triennial reports indicate mode share targets remain unachieved. 4.1.2 City of San Bruno Plans and Policies This section summarizes City of San Bruno policies as they relate to the portion of the Project’s proposed infrastructure improvements within its jurisdiction. The Project EIR is intended to provide CEQA clearance for subsequent discretionary approvals required by other agencies, including the City of San Bruno, for proposed offsite improvements located outside of the City of South San Francisco’s jurisdiction. Analysis regarding these City of San Bruno policies is included here for that purpose; however, these policies do not apply to the Project overall. 4.1.2.1 General Plan Policies The following City of San Bruno General Plan policies are relevant to the Project’s proposed offsite improvements within San Bruno.11 • T-A Provide for efficient, safe, and pleasant movement for all transportation modes—vehicles, bicycles, transit, and pedestrians. • T-E Focus San Bruno’s efforts on improvements to the non-motorized transportation system (i.e., bicycles, pedestrians, strollers, etc.) adjacent to transit corridors and stations, and their connections to those systems. • T-F Provide efficient local transit—such as a shuttle system—to the BART and Caltrain stations to avoid dependence on individual motor vehicles. 11 The City of San Bruno General Plan includes policies related to automobile LOS, including Policy T-B stating that acceptable levels of service for vehicular movement along the city’s street network should be maintained, and that “[a]cceptable level of service could vary based on characteristics of the area under consideration.” Under SB 743, LOS or similar measures of traffic congestion are no longer considered a significant impact under CEQA. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 43 • T-I Develop and maintain a comprehensive bicycle network within San Bruno, providing connections to BART and Caltrain, surrounding cities, employment and shopping areas, and natural areas. • T-J Develop a safe, convenient, and continuous network of sidewalks and pedestrian paths within the city. • T-2 Ensure that all transportation improvements— roadway, transit, bicycle, and pedestrian—are designed and constructed according to Americans with Disabilities Act standards. Improve existing facilities so they are compliant with American Disability Act standards. • T-43 Create a “pedestrian-friendly” environment surrounding the BART and Caltrain stations by installing additional street trees, lighting, signage, and widening sidewalks along streets adjacent to these stations. • T-47 Improve multi-modal access—specifically for pedestrians, cyclists, and transit passengers—to the BART and Caltrain stations through improvements along Huntington Avenue. • T-70 Identify funding for and implement as a priority bicycle/pedestrian paths along the BART and Caltrain track alignments (Huntington Avenue and Herman Avenue) within the city limits. Coordinate with the Linear Park planned in South San Francisco and Millbrae. 4.1.2.2 Transit Corridors Plan Policies The City of San Bruno Transit Corridors Plan articulates the community's vision for revitalized commercial corridors in proximity to the San Bruno Avenue Caltrain Station. The following policies are relevant to the Project’s proposed offsite improvements within San Bruno: • TRANS-B Ensure increased transit connectivity within and to/from the Transit Corridors Area and provide for transit amenities at stops and stations that increase the visibility of stops/stations and improve the comfort and convenience for transit riders. • TRANS-C Encourage improved bicycle connectivity and enhanced bicycle parking opportunities within the Transit Corridors Area linking the surrounding land uses and future Caltrain station. ◦ TRANS-C.1 Provide Class II bicycle lanes on Huntington Avenue north of San Bruno Avenue. • TRANS-D Facilitate pedestrian access and safety through pedestrian enhancements, including the provision of enhanced crosswalks at all intersections and wider sidewalks and pedestrian amenities along the transit corridors. ◦ TRANS-D.1 Provide enhanced crosswalks at all crossings in Transit Corridors Area. As appropriate, enhanced crosswalks should include pedestrian bulbouts, median refuge islands or special paving treatments. • TRANS-E Develop and implement a parking management strategy for the Plan area that makes efficient use of the City’s parking supply through shared parking strategies and that provides the lowest number of parking spaces while still maintaining the viability of the Plan through efficient use of the parking supply within the Plan Area. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 44 • TRANS-F Develop and implement a Transportation Demand Management (TDM) Program that reduces the amount of peak period motor vehicle traffic and encourages the use of modes other than the single-occupant vehicle. 4.1.2.3 Walk ‘n Bike Plan The City of San Bruno Walk ‘n Bike Plan identifies improvements to support safe, comfortable, and convenient walking and biking within the City. The Plan identifies specific improvements including streetscape enhancements and a Class IV separated bikeway along Huntington Avenue, gap closures of Class II bicycle lanes along Sneath Lane, and a Class III bicycle route along Herman Street. 4.1.3 Regional Plans and Policies This section summarizes regional policies that relate to the Project. 4.1.3.1 MTC/ABAG Plan Bay Area 2040 Plan Bay Area is the Bay Area’s Regional Transportation Plan and Sustainable Communities Strategy. Plan Bay Area 2040 is a state-mandated, integrated long-range transportation and land use plan intended to meet greenhouse gas reduction targets. Plan Bay Area 2040 identifies various action items related to achieving these targets. The following action items relate to the Project: • Increase transportation access to growing and potential job centers; • Support regional growth by balancing housing, transit-oriented jobs, and industrial uses. 4.1.3.2 San Mateo City/County Association of Governments Congestion Management Program The San Mateo City/County Association of Governments (C/CAG) is the Congestion Management Agency (CMA) for San Mateo County and is authorized to set State and federal funding priorities for improvements affecting the San Mateo County Congestion Management Program (CMP) roadway system. The C/CAG- designated CMP roadway system in South San Francisco includes State Route (SR) 82 (El Camino Real), U.S. 101, Interstate I-380, and I-280.12 C/CAG has adopted guidelines to reduce the number of net new vehicle trips generated by new land development. These guidelines apply to all developments that generate 100 or more net new peak hour vehicular trips on the CMP network and are subject to CEQA review. C/CAG calls for projects that meet the criteria to determine if a combination of acceptable measures is possible that has the capacity to “fully reduce,” through the use of a trip credit system, the demand for net new trips that a project is anticipated to generate on the CMP roadway network (including the first 100 trips). C/CAG has published a list of 12 C/CAG sets LOS standards for the CMP network, but these LOS standards do not apply to CEQA per SB-743. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 45 mitigation options in a memorandum that also outlines a process for obtaining C/CAG approval of the Transportation Demand Management (TDM) Plan. 4.1.3.3 BART Transit-Oriented Development Policy BART’s Transit Oriented Development (TOD)13 Policy informs BART’s internal and external approach to development near BART stations. The following goals and strategies are relevant to the Project: • Goal B Sustainable Communities Strategy. Lead in the delivery of the region’s land use and transportation vision to achieve quality of life, economic, and greenhouse gas reduction goals. • Goal E Transportation Choice. Leverage land use and urban design to encourage non-auto transportation choices both on and off BART property, through enhanced walkability and bikeability, and seamless transit connectivity. • Strategy B1 Support Transit-Oriented Districts: Proactively support local jurisdictions in creating station area plans and land use policies that: a) encourage transit-supportive, mixed-use development on and around station properties, b) enhance the value of BART land, and c) enhance the performance of the BART system as a whole. • Strategy B2 Form partnerships with public agencies, developers and landowners, community development organizations, finance entities, and consider strategic land acquisition to help build TOD both on and off BART property. • Strategy C1 Utilize BART’s TOD Guidelines to ensure future development and investments seamlessly connect BART stations with surrounding communities • Strategy C3 Utilize strategies including mixed-use development, transportation demand management, and pedestrian-friendly urban design to encourage reverse-commute, off-peak, and non-work trips on BART and other modes of non-auto transportation, thereby reducing greenhouse gas emissions. 4.1.4 Policy Consistency Analysis The Project, including the associated proposed offsite improvements, is consistent with applicable adopted transit, bicycling, and walking policies within the Cities of South San Francisco and San Bruno. The Project and associated proposed offsite improvements would improve connectivity between the San Bruno BART Station and the Lindenville neighborhood; provide more direct pedestrian routes; add Class II bike lanes on Southline Avenue, in addition to Class I and Class III bike facilities within the Project area; extend the Centennial Way Trail; and provide a range of amenities and features within the Project site, including bicycle parking, showers, and changing facilities, among other features. The new Southline Avenue/Sneath Lane/Huntington Avenue/Maple Avenue intersection would include a signalized trail and pedestrian crossings with high-visibility crosswalks. Near the San Bruno BART Station, the Project includes circulation 13 BART Transit-Oriented Development Policy, Amended April 23 2020 https://www.bart.gov/sites/default/files/docs/BART%20Transit-Oriented%20Development%20Policy_Amended2020-04-23.pdf Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 46 enhancements to Huntington Avenue, including widening sidewalks, upgrading curb ramps, providing high- visibility crosswalks, adding bulbouts, and extending the Centennial Way Trail. The Project supports public transit ridership by providing enhanced connectivity to BART and SamTrans, a dedicated signalized bus entrance to the SamTrans transit center, and offering a shuttle service to Caltrain. The Project includes a TDM program to meet a 45 percent mode share target required by the City. The Project is also consistent with regional plans including Plan Bay Area, C/CAG’s Congestion Management Program, and BART’s TOD Policy. While the Project site was not specifically identified as a Priority Development Area in Plan Bay Area (adjacent sites in the City of San Bruno were identified), its location in a Transit Priority Area near the San Bruno BART Station is consistent with Plan Bay Area’s goals to better integrate land use and transportation planning as well as BART’s goals to encourage reverse-commute trips to employment centers near stations. The Project’s Preliminary TDM program and associated circulation improvements are intended to fulfill C/CAG trip reduction requirements and is consistent with the above described goals by BART and C/CAG to encourage transit ridership and reduce vehicle trips. 4.2 VMT Analysis This section analyzes VMT for the Project in relation to the criteria in section 3.2.1. The Project would affect VMT in two ways: the addition of Project-related travel from land use changes, and the effect of the Southline Avenue extension on travel patterns within the surrounding area. These topics are analyzed below. 4.2.1.1 VMT Screening – Land Use Project SB 743 applies to the Project, which is a qualifying employment center Project located on an infill site within a transit priority area, as those terms are defined under Section 21099 of the Public Resources Code. As discussed in Sections 3.1 and 3.2.1, CEQA Guidelines Section 15064.3(b)(1), implementing SB 743, establishes a presumption of less than significance for VMT impacts related to qualifying land use Projects. The Project is located within a qualifying transit priority area, as it is located within one-half mile of a major transit stop, including the San Bruno BART station and a frequent bus route (the SamTrans ECR route, which operates every 15 minutes), as shown in Figure 2-1. Both the San Bruno BART station and ECR route stops are considered major transit stops per Section 21099 of the Public Resources Code. A project qualifies for a presumption of a less than significant impact provided that project-specific and location-specific information supports this presumption. The following Project-specific and location-specific information supports a presumption of less than significant impact: • The Project’s proximity to BART provides a high-frequency regional transit connection to San Francisco, the East Bay, and northern San Mateo County, and its proximity to the SamTrans ECR route provides a frequent local transit connection within San Mateo County. Employee access to Caltrain via a shuttle service may further enable a regional transit connection to San Francisco, the Peninsula, and the South Bay. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 47 • The Project includes infrastructure improvements to support direct connections to transit and active transportation, including widening sidewalks and extending the Centennial Way Trail to the San Bruno BART Station, adding pedestrian bulbouts and high-visibility crosswalks, and providing a shuttle service to connect to Caltrain. • The Project would allow for development of up to 2,800,000 SF (a maximum FAR of 2.4), which is substantially more dense than surrounding land uses as well as the existing land use at the Project site. The Project density is consistent with transit supportive development for station areas as defined in BART TOD Guidelines, which calls for medium to high density development that is greater than the community average within a 5 to 10-minute walk of stations. • The Project’s parking supply is below the City of South San Francisco requirements applicable to the existing zoning district and comparable office/R&D uses. The project, inclusive of Phase 1, would include vehicle parking up to a maximum of 2.2 parking spaces per 1,000 square feet of office space, which is less than the City’s standard requirement of 2.9 spaces per 1,000 square feet for similar business/professional office and R&D developments. The Project includes a TDM program to require that at least 45 percent of trips occur via transit, active transportation, and carpooling. • The Project is consistent with the goals of Plan Bay Area to provide transit-oriented employment growth. Based on these features in combination with its transit-oriented location, both Phase 1 of the Project as well as the Project Buildout meet OPR’s criteria for a presumption of less than significant VMT impact. 4.2.1.2 VMT Analysis – Southline Avenue Extension The addition of Southline Avenue connecting Sneath Lane/Huntington Avenue and South Linden Avenue, a new street extension of approximately one quarter mile in length, would provide additional capacity for east-west travel in the Project area. Under existing conditions, there is no direct access between South Linden Avenue and Sneath Lane; this connection requires detouring about 1.3 miles either to the south on Huntington Avenue to Herman Avenue/Dollar Avenue, or detouring north on Huntington Avenue to South Spruce Avenue and Victory Avenue. To assess the effect of the new connection on local VMT, the City of South San Francisco Travel Model was used. The City’s model provides greater detail in the local transportation network compared to the C/CAG Model and allows for dynamic assignment of vehicles to the most efficient route, therefore accounting for changes in travel behavior due to new connections and roadways. Overall, the Southline Avenue extension is expected to result in a modest reduction in VMT produced by vehicles traversing the Project area, specifically affecting local traffic patterns by shifting east-west trips from South Spruce Avenue, San Bruno Avenue, and Scott Street toward the new shorter and more direct route. This modified circulation results in a slight reduction in VMT. Results are shown in Table 4-1. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 48 Table 4-1. VMT Effects of Southline Avenue Extension within South San Francisco and San Bruno Area Existing Daily Roadway Network VMT Daily Roadway Network VMT with Southline Avenue Extension Difference VMT in South San Francisco and San Bruno 5,077,500 5,072,600 -4,900 Source: Fehr & Peers, 2020 4.3 Site Plan Analysis This section analyzes the Project Buildout’s effects on local circulation within the extents of the Project site and related offsite improvement areas. Similarities and differences between the Project Buildout and Phase 1 Project are noted where applicable. Project Buildout conditions are analyzed in the Cumulative 2040 context, while Phase 1 Project conditions are analyzed in the 2024 context, reflecting anticipated construction timing. The Project’s site plan provides a preliminary design of building layouts and transportation infrastructure. Project-related infrastructure changes include the Southline Avenue extension, driveways, sidewalks, traffic signals, the Centennial Way Trail extension, reconfiguration of bus and pedestrian access to the San Bruno BART Station, and the realignment of the at-grade rail crossing of Caltrain. These components would be finalized over the course of the Phase 1 and Project Buildout design processes and designed to applicable standards. 4.3.1 Multimodal Analysis The following sections evaluate the Project’s proposed changes to existing circulation and transportation infrastructure, as shown in Figure 4-2. As detailed in this analysis, the proposed circulation and transportation improvements associated with the Phase 1 Project and Project Buildout would sufficiently accommodate the change in land use associated with an office/R&D campus in a manner consistent with applicable Caltrans and Highway Design Manual design standards, and would not introduce any design hazards. 4.3.1.1 Phase 1 Centennial Way Trail Extension and BART Station Access The Project would extend the Centennial Way Trail to the San Bruno BART Station, providing a 15- to 17- foot-wide multi-use path along the west side of Huntington Avenue. The path intends to serve both pedestrians and bicyclists in a shared use condition similar to the Centennial Way Trail to the north while retaining the bioswale area adjacent to the SamTrans Transit Center. Viswalk was used to analyze potential conflicts between pedestrians and bicyclists along the Centennial Way trail extension during AM and PM peak hours. The analysis simulates pedestrian and bicycle behavior, interactions, and usage of space. Pedestrian and bicycle trips were distributed to reflect the proposed Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 49 Project’s travel demand, particularly the trips between the Project and BART and SamTrans. During peak hours, the path would serve about 550 to 650 pedestrians per hour traveling to and from the BART Station as well as about 100 to 150 bicyclists. Pedestrian and bicycle flows exiting the BART station were metered to reflect the BART train schedule during the AM and PM peak hours. The Viswalk analysis evaluated “pedestrian space,” described as the average amount of area available for a pedestrian walking along a trail, sidewalk or crosswalk. Pedestrian space can also be expressed as the inverse of pedestrian density. The Highway Capacity Manual (HCM) 6th Edition provides a qualitative description of the pedestrian space that can be used to evaluate the performance of pedestrian facilities. Since pedestrians will comprise the vast majority of users on the Centennial Way Trail during peak hours, analyzing pedestrian space helps illustrate how much room remains for bicyclists to pass pedestrians as well as the potential for conflicts between modes. This scale is summarized in Table 4-2 shows a worst-case condition for pedestrian space experienced by users of the Centennial Way Trail during the AM and PM peak hours. Table 4-2: Pedestrian Space Crowding Scale Pedestrian Space (square feet per pedestrian) Description > 60 Ability to move in desired path, no need to alter movements > 40-60 Occasional need to adjust path to avoid conflicts > 24-40 Frequent need to adjust path to avoid conflicts > 15-24 Speed and ability to pass slower pedestrians restricted > 8-15 Speed restricted, very limited ability to pass slower pedestrians <= 8 Speed severely restricted, frequent contact with other users Notes: Based on the Highway Capacity Manual 6th Edition Source: Fehr & Peers, 2020. The Viswalk results indicate that the proposed 15 to 17-foot-wide trail extension is sufficiently sized to accommodate forecasted pedestrian and bicycle volumes. The analysis identified hot spots for pedestrian space at the corners of the Huntington/BART and Huntington/Southline Avenue intersections, particularly the southwest corner of the Huntington/BART intersection during the AM peak hour due to the heavy pedestrian and bicycle flows existing the BART station. A visual inspection of the Viswalk simulation showed that while substantial crowding would occur at this corner as pedestrians wait for the ‘walk’ signal, the duration of the ‘walk’ signal and the lack of conflicts with vehicular movements would allow all pedestrians to cross in the same signal cycle. In essence, a high volume of pedestrians after a train arrival would control the speed of travel on the trail adjacent to the station, then spacing between pedestrians would increase walking farther from the station allowing bicyclists to comfortably pass. Therefore, the proposed design is unlikely to pose a hazardous condition. Project Improvement Locations Figure 1-3\\Fpsf03.fpainc.local\data\Projects\2020_Projects\SF20-1089_Southline EIR\Graphics\GIS\MXD\CA_Template_LetterPortrait.mxdCentennial Way Trail Extension and BART Station Access Huntington Ave/Sneath Ln/Southline Ave/Maple Ave Signalized Intersection Southline Ave/South Linden Ave/Dollar Ave Signalized Intersection A B C D E Driveways Re-aligned at-grade crossing Potential shuttle stop locations Southline Ave/Central Project Signalized Intersection Dedicated bus signalized entrance Driveways Analyzed for Signal WarrantsX Add pedestrian crossing Add upgraded pedestrian crossing New cul-de-sac ADA sidewalk improvements Traffic signal modifications and new pedestrian crossing New Southline Avenue and Class II Bike Lane Location of southern mobility hub to be adjusted to south side of Building 7; refer to Project Description Figure 3-15 AM + PM Peak Hours Pedestrian Spacing Figure 4-3 >60 Pedestrian Space(square feet per pedestrian) Ability to move in desired path, no need to alter movements Signalized IntersectionOccasional need to adjust path to avoid conflicts Frequent need to adjust path to avoid conflicts Speed and ability to pass slower pedestrians restricted Speed restricted, very limited ability to pass slower pedestrians Speed severely restricted, frequent contact with other users Undefined >40-60 >24-40 >15-24 >8-15 <=8 AM PM HUNTING TON A V EN U E SNEATH LAN E TANFORAN A VE N U ESOUTHLINE AVENUEBus Transit Center B A R T S t a t i o n E n t r a n c e : ~ 2 5 0 - f t HUNTING TON A V EN U E SNEATH LAN E TANFORAN A VE N U ESOUTHLINE AVENUEBus Transit Center B A R T S t a t i o n E n t r a n c e : ~ 2 5 0 - f t \\Fpsf03.fpainc.local\data\Projects\2020_Projects\SF20-1089_Southline EIR\Graphics\AI Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 52 The Project would add a new crosswalk and pedestrian bulbout on the south side of the SamTrans Transit Center driveway to provide a more direct connection between the BART Station to the eastern sidewalk along Huntington Avenue. The eastern sidewalk would be rebuilt to achieve ADA compliance. Walking trips to and from the Project are likely to use both the eastern sidewalk and western trail along Huntington Avenue. 4.3.1.2 Huntington Avenue/Sneath Lane/Southline Avenue/Maple Avenue Intersection The Project would create a new signalized intersection between Huntington Avenue/Sneath Lane/Southline Avenue/Maple Avenue at the Project entrance. Huntington Avenue would be aligned with Maple Avenue, while Sneath Lane would be aligned with Southline Avenue. The western leg of the intersection would include a crossing for the Centennial Way Trail, while high visibility crosswalks would be provided on the remaining northern, southern, and eastern legs of the intersection. This trail crossing was analyzed as a protected phase without conflicting right-turn-on-red movements by southbound and eastbound vehicles. The intersection would change access to several adjacent driveways. Access to the BART maintenance facility driveway on the north side of Huntington Avenue would remain in the westbound direction but would be restricted in the eastbound direction. Northbound bus access from Huntington Avenue to the SamTrans Transit Center would be relocated to a signalized bus-only left turn (serving about five buses per hour throughout the day). Eastbound access to the SamTrans Transit Center would remain. Adding this intersection would also affect Tanforan Avenue. Tanforan Avenue would be separated from Maple Avenue while maintaining a connection with Huntington Avenue East. No vehicular Project access would occur on Tanforan Avenue. Consequently, traffic volumes would decline on Tanforan Avenue, particularly vehicle and truck traffic associated with industrial sites in Lindenville. 4.3.1.3 Southline Avenue/Central Project Driveway The Southline Avenue/Central Project Driveway intersection (at Buildings 1, 3, 6, and 7) would experience very high pedestrian volumes during peak hours as a result of its location between Project buildings, parking facilities, shuttle stops, and amenities. Crosswalk volumes are expected to be in excess of 500 pedestrians per crosswalk leg. Consequently, a pedestrian scramble phase (in which pedestrians cross all legs of the intersection at the same time) was analyzed as the optimized condition to separate pedestrian and vehicle movements. With a pedestrian scramble phase, conflicts between modes are expected to be minimal. 4.3.1.4 Southline Avenue/South Linden Avenue/Dollar Avenue Intersection Southline Avenue would connect to a realigned intersection of South Linden Avenue/Dollar Avenue on the east side of the Project. The northern leg of South Linden Avenue would align with Dollar Avenue, while Southline Avenue would connect across a realigned at-grade rail crossing of Caltrain to San Mateo Avenue. Eventually, it is anticipated that this crossing would be grade separated through a multi-agency planning and implementation process; both the cities of South San Francisco and San Bruno have recommended that planning efforts proceed under the “Alternative 1” design, which would partially lower South Linden Avenue and partially raise the railway. The Project’s design is compatible with the preferred Alternative 1 design. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 53 The proposed grade separation project will be subject to a separate CEQA review and approval process not related to the Project; the grade separation project also requires public financing for implementation, which has not yet been obtained. 4.3.2 Signal Warrant Analysis A signal warrant analysis to determine the potential need for traffic signals at unsignalized intersections was conducted for unsignalized Project intersections to assess potential hazards associated with Project-related vehicle and pedestrian volumes in accordance with criteria in the California Manual on Uniform Traffic Control Devices (CA-MUTCD). Signal warrants were tested for the five new full-access driveways, shown on Figure 4-2, on the Project based on the Peak Hour and Pedestrian Volume methodologies described in the CA-MUTCD, Section 4C.04 and 4C.05. As shown in Table 4-3, no driveways meet peak hour signal warrants under either Phase 1 or Project Buildout conditions. One driveway intersection at Maple Avenue (south of Building 4) would potentially meet pedestrian volume warrants; however, the Project’s proposed Rapid- Rectangular Flashing Beacon is expected to provide sufficient prioritization for pedestrians crossing at this location to fulfill the anticipated need. Therefore, no signal warrants are met under Phase 1 Project and Project Buildout conditions. Table 4-3: Signal Warrant Analysis Driveway Driveway Location Project Buildout Conditions Peak Hour Signal Warrant Met Pedestrian Volume Warrant Met A South Linden Avenue No No B Maple Avenue, south of Building 4 No No1 C Maple Avenue, west of Building 4 No No D Maple Avenue, east of Building 5 No No E Dollar Avenue No No Notes: Based on the CA-MUTCD 1Project would provide a Rapid-Rectangular Flashing Beacon to accommodate crossing needs Source: Fehr & Peers, 2020. 4.3.3 Phase 1 At-Grade Rail Crossing Analysis The Project is located adjacent to the active rail corridor used by both Caltrain and limited evening freight activity. Under existing conditions, Caltrain operates five trains per hour, per direction during peak periods and one to two trains per hour, per direction during off-peak periods, while one to two trains per day operate during late evening hours. In 2022, the Peninsula Corridor Electrification Project will increase Caltrain service to six trains per hour, per direction during peak periods. By 2040, Caltrain plans to operate Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 54 eight trains per hour, per direction, while California High Speed Rail would operate four trains per hour, per direction, for a total of 12 trains per hour, per direction. Vehicle traffic associated with the Project would increase the traffic volumes at the existing at-grade rail crossings at South Linden Avenue and at Scott Street; however, the Project (Phase 1 and Buildout) would not exacerbate potential safety hazards at these locations. as further described in Section 3.7.3.1 below. While a grade separation is planned, the at-grade crossing condition was analyzed to reflect a worst-case scenario given that the grade separation currently is unfunded and not yet approved. The Project’s design of Southline Avenue maintains flexibility for a future grade separation; in the interim, it includes a reconfigured at-grade rail crossing to connect Southline Avenue with South Linden Avenue. No changes to the Scott Street at-grade rail crossing would occur with the Project. 4.3.3.1 South Linden Avenue At-Grade Rail Crossing The rail crossing most directly affected by the Project is located on South Linden Avenue, immediately east of Dollar Avenue. The number of vehicles using this at-grade crossing increases due to both Project trips and the construction of Southline Avenue, which provides new east-west access connecting to Sneath Lane. Operations affecting this railroad crossing and nearby intersections were modeled using the VISSIM traffic operations analysis software. Vissim analyzes traffic by simulating and capturing the interactions between individual cars, trucks, buses, trains, pedestrians, and bicycles and can provide detailed queuing information and indication of potential for vehicles to not clear an at-grade crossing. Table 4-4 shows the storage space and simulated queuing activity under 2040 Plus Project Buildout conditions. With the Project Buildout, there is potential for queues exceeding available storage for the westbound movements at Southline Avenue and Dollar Avenue. However, by synchronizing the traffic signal with the at-grade crossing, the Project would minimize potential risk of conflicts since vehicles would be flushed out of the rail crossing prior to a train approaching. The inclusion of medians would also enhance safety by inhibiting vehicles from traveling around crossing gates. Consequentially, the risk of conflicts under either the Phase 1 Project or Project Buildout would not change substantially relative to the existing condition. 4.3.3.2 Scott Street At-Grade Rail Crossing The second rail crossing potentially affected by the Project is located at Scott Street, located about 1,200 feet to the south of the Project. By adding Southline Avenue as a more direct connection between Huntington Avenue and San Mateo Avenue, the Project would decrease traffic volumes on Scott Street compared to No Project conditions. Because the total number of vehicles crossing the corridor at this location would decrease, the Phase 1 Project and Project Buildout would not exacerbate potential safety hazards at this location. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 55 Table 4-4. Queuing at Linden Avenue At-Grade Rail Crossing – 2040 Project Buildout Intersection Movement Storage Space Average Queue Length (ft) 95th Percentile Queue Length (ft) Queue exceeds storage? AM Peak Hour Southline Avenue / Dollar Avenue WBT 80 170 300 Yes Southline Avenue / Dollar Avenue WBL 60 160 290 Yes Linden Avenue/ San Mateo Avenue SBT 450 100 140 No Linden Avenue/ San Mateo Avenue SBL 450 190 250 No PM Peak Hour Southline Avenue / Dollar Avenue WBT 80 530 600 Yes Southline Avenue / Dollar Avenue WBL 60 530 600 Yes Linden Avenue/ San Mateo Avenue SBT 450 190 250 No Linden Avenue/San Mateo Avenue SBL 450 320 390 No Source: Fehr & Peers, 2020 4.4 Offsite Transportation Analysis 4.4.1 Signal Warrant Analysis A signal warrant analysis was conducted for the intersection of Huntington Avenue/Herman Street/Forest Lane to assess potential hazards associate with Project-related vehicle volumes. This intersection, which is presently all-way stop controlled, was selected based on the volume of Project-related vehicle traffic added along multiple approaches (Huntington Avenue and Herman Street). Signal warrants were tested based on the Peak Hour methodology described in the CA-MUTCD Section 4C.04. There are no other unsignalized intersections in the study area where the Project is expected to add substantial volume on unsignalized approaches. The Huntington Avenue/Herman Street/Forest Lane intersection meets the peak hour signal warrant under all analysis scenarios during the PM peak hour, including existing, 2024 No Project, 2024 plus Phase 1, 2040 No Project, and 2040 Plus Project Buildout conditions. The intersection experienced six injury collisions between 2015 and 2019. Phase 1 of the Project would add approximately 11 PM peak hour trips to the intersection during the PM peak hour, which is unlikely to materially change the intersection’s operations. The Project Buildout would add approximately 301 PM peak hour trips, which would more substantially affect intersection operations. The addition of Project Buildout-related trips may exacerbate risk of collisions Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 56 at this multi-lane stop-controlled intersection, which experienced eight reported injury collisions between 2014 and 2019 (five vehicle-vehicle collisions, two vehicle-pedestrian collisions, and one-vehicle-bicycle collision).14 4.4.2 Freeway Ramp Queuing Analysis Ten freeway off-ramps were analyzed based on Project trip assignment patterns to assess conditions where the addition of Project trips may result in hazards to road users. The study locations are listed below and shown in Figure 3-10. 1. I-280 Southbound Off-Ramp at Rollingwood Drive & Sneath Lane 2. I-280 Southbound Off-Ramp at San Bruno Avenue 3. I-280 Northbound Off-Ramp at San Bruno Avenue 4. US-101 Southbound Off-Ramp at San Bruno Avenue 5. US 101 Northbound Off-Ramp at San Bruno Avenue 6. I-380 Westbound Off-Ramp at El Camino Real 7. I-380 Eastbound Off-Ramp at El Camino Real 8. US-101 Southbound Off-Ramp at Airport Boulevard 9. US-101 Southbound Off-Ramp at Produce Avenue 10. US-101 Northbound Off-Ramp at South Airport Boulevard Traffic counts were collected at the approaches and departures to the ten freeway on- and off-ramps during the morning (7:00 AM to 9:00 AM) and evening (4:00 PM to 6:00 PM) peak periods in 2017 and 2019 prior to the onset of the COVID-19 pandemic, as further described above. During all counts, weather conditions were generally dry, no unusual traffic patterns were observed, and local school districts were in regular session. Table 4-5 and Table 4-6. present weekday AM and PM peak hour vehicle queues at the ten US-101 off-ramp study locations under existing, 2024 (Phase 1), and 2040 (Project Buildout) conditions. Due to the Project’s access to these ten freeway ramps for US-101, I-280, and I-380 via several roadways and driveways, Project-related traffic would distribute across a number of potential routes including arterials and other roadways. Consequently, Project-related traffic volumes would not result in queues exceeding the total ramp storage distance to the freeway mainline at any of the study locations under any scenarios. As such, the Project is not expected to create or contribute to hazards resulting from speed differentials at off-ramp diverges on Caltrans facilities. 14 California Statewide Integrated Traffic Records System (SWITRS), 2014-2019, retrieved via the Transportation Injury Mapping System (TIMS) Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 57 Table 4-5. Existing and 2024 Weekday AM and PM Peak Hour 95th Percentile Queues Approach Lanes Storage Distance (ft) Existing 2024 No Project 2024 Plus Project (Phase 1) Queue Length Queue Length Queue Length AM PM AM PM AM PM 1. I-280 Southbound Off-Ramp at Rollingwood Drive & Sneath Lane Left/Through 1,200 65 190 68 197 77 203 Right 150 65 72 67 62 68 66 2. I-280 Southbound Off-Ramp at San Bruno Avenue* Left 120 197 153 205 158 209 161 Left/Through 840 183 90 190 92 197 96 Through/Right 3,615 Right 80 54 51 58 51 62 57 3. I-280 Northbound Off-Ramp at San Bruno Avenue* Left 230 85 202 89 211 91 207 Through/Left/Right 1,280 334 660 365 701 325 701 4. US-101 Southbound Off-Ramp at San Bruno Avenue* Left 280 112 81 112 84 56 86 Left/Through 960 112 82 112 84 56 86 Right 280 24 130 24 136 24 140 5. US 101 Northbound Off-Ramp at San Bruno Avenue* Left 560 256 345 260 391 295 419 Right (through) 2,400 69 68 93 86 102 103 6. I-380 Westbound Off-Ramp at El Camino Real* Left 980 246 303 248 303 248 303 Right 980 252 834 280 838 296 799 7. I-380 Eastbound Off-Ramp at El Camino Real* Left 520 131 340 135 352 157 355 Through/Left/Right 1,760 96 263 105 287 151 306 Right 330 88 245 96 267 118 277 8. US 101 Southbound Off-Ramp at Airport Boulevard Left 430 208 143 213 166 230 174 Through 720 209 224 220 240 230 254 9. US 101 Southbound Off-Ramp at Produce Avenue Left 620 220 162 182 168 221 202 Right 100 69 40 58 40 59 42 10. US 101 Northbound Off-Ramp at South Airport Boulevard Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 58 Table 4-5. Existing and 2024 Weekday AM and PM Peak Hour 95th Percentile Queues Approach Lanes Storage Distance (ft) Existing 2024 No Project 2024 Plus Project (Phase 1) Queue Length Queue Length Queue Length AM PM AM PM AM PM Left/Through 740 473 176 492 188 492 182 Right 740 45 33 46 34 46 34 Notes: Ramps analyzed using Synchro software; * indicates additional analysis with SimTraffic software. Bold type indicates conditions where queue length exceeds storage capacity due to project volumes (none applicable). Queues do not take into account downstream spillover from adjacent intersections. Storage distance and queues in feet per lane. Source: Fehr & Peers, 2020 Table 4-6. 2040 Weekday AM and PM Peak Hour 95th Percentile Queues Approach Lanes Storage Distance (ft) 2040 No Project 2040 Plus Project (Buildout) Queue Length Queue Length AM PM AM PM 1. I-280 Southbound Off-Ramp at Rollingwood Drive & Sneath Lane Left/Through 1200 105 215 118 230 Right 150 74 91 104 103 2. I-280 Southbound Off-Ramp at San Bruno Avenue* Left 120 232 179 243 195 Left/Through 840 221 102 227 120 Through/Right 3615 Right 80 68 68 74 79 3. I-280 Northbound Off-Ramp at San Bruno Avenue* Left 230 93 225 419 240 Through/Left/Right 1,335 394 818 1,171 778 4. US-101 Southbound Off-Ramp at San Bruno Avenue* Left 280 115 87 65 88 Left/Through 960 116 87 65 89 Right 280 26 138 26 138 5. US 101 Northbound Off-Ramp at San Bruno Avenue* Left/Through 2,600 277 603 2,299 1,040 Right 560 324 335 961 498 6. I-380 Westbound Off-Ramp at El Camino Real* Left 980 253 212 250 217 Right 980 331 668 359 637 7. I-380 Eastbound Off-Ramp at El Camino Real* Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 59 Table 4-6. 2040 Weekday AM and PM Peak Hour 95th Percentile Queues Approach Lanes Storage Distance (ft) 2040 No Project 2040 Plus Project (Buildout) Queue Length Queue Length AM PM AM PM Left 520 157 294 234 378 Through/Left/Right 1,760 170 271 271 312 Right 330 160 252 242 273 8. US 101 Southbound Off-Ramp at Airport Boulevard Left 430 278 253 360 270 Through 720 282 307 368 318 9. US 101 Southbound Off-Ramp at Produce Avenue Left 620 208 182 272 226 Right 100 63 43 63 45 10. US 101 Northbound Off-Ramp at South Airport Boulevard Left/Through 740 526 283 514 274 Right 740 46 39 47 39 Notes: Ramps analyzed using Synchro software; * indicates additional analysis with SimTraffic software . Bold type indicates conditions where queue length exceeds storage capacity due to project volumes (none applicable). Storage distance and queues in feet per lane. Source: Fehr & Peers, 2020 4.4.3 Transit Performance Analysis This section analyzes the Project’s effects on the performance of transit services, including delay to transit vehicles and effects on transit capacity. 4.4.3.1 Transit Delay The Phase 1 Project and Project Buildout would generate vehicle trips in the vicinity of existing transit services, which could potentially contribute toward delays for transit operations. To assess the Project’s potential effects on transit travel times and delay to transit riders, the VISSIM traffic analysis software was used to report total travel times for the ECR SamTrans bus route, which diverts via Sneath Lane from El Camino Real to serve the San Bruno BART Station. This route was analyzed because it provides the most frequent service and would be most heavily exposed to Project-related delays; findings would also apply for portions of the 140 and 141 SamTrans bus routes that overlap with the ECR route. Table 4-7 shows travel times along these transit routes under 2040 No Project and 2040 Plus Project Buildout conditions. Travel times are taken for the portion of each route that travels from El Camino Real along Sneath Lane to the BART Station, then returning to El Camino Real; this represents around one mile worth of travel. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 60 Table 4-7. Average ECR Travel Times between El Camino Real and the San Bruno BART Station Study Period Round Trip Transit Travel Time (Minutes) Existing 2040 No Project 2040 Plus Project Project Effect (2040) AM Peak Hour (ECR NB) 6 6 7 +1 AM Peak Hour (ECR SB) 7 7 8 +1 PM Peak Hour (ECR NB) 6 6 9 +3 PM Peak Hour (ECR SB) 8 8 11 +3 Notes: Travel times measured include the time needed to travel through the El Camino Real/Sneath Lane intersection via the route diversion through the San Bruno BART Station Transit Center. Values rounded to nearest minute. Based on Vissim simulation. Source: Fehr & Peers, 2020 The Project Buildout would result in a change of transit travel times for the ECR route totaling about one minute each way in the AM peak hour and three minutes each way in the PM peak hour. During the PM peak hour, congestion associated with added vehicle trips at the split phase signal at the El Camino Real/Sneath Lane intersection represents the primary source of delay. Given the route operates every 15 minutes during the AM and PM peak periods, and has a one-way travel time of about 110 minutes, this change in travel time is unlikely to affect the route’s performance overall or require additional buses to maintain comparable headways. Given that traffic volumes will be lower under Phase 1 Project conditions, the Phase 1 Project is also unlikely to affect the performance of bus services. 4.4.3.2 Transit Capacity and Crowding The Phase 1 Project and Project Buildout are anticipated to add net new transit trips to both BART, Caltrain, and SamTrans during the AM and PM peak commute periods. BART and Caltrain currently experience peak period crowding along certain segments of key routes. A majority of transit trips would occur via BART (up to about 800 to 900 Project-related peak hour trips under Project Buildout conditions), while trips would also occur on Caltrain (300 to 400 peak hour trips) and SamTrans (70 to 80 peak hour trips). Phase 1 of the Project would add slightly less than one quarter of these Project Buildout totals. Project-related BART trips would largely travel in the reverse-commute direction in which BART has ample capacity. Under existing conditions, about 60 to 65 percent of BART passengers riding between San Bruno and South San Francisco are traveling northbound during the AM peak hour and Southbound during the PM peak hour. San Bruno Station mirrors these patterns, with most passengers entering the station during the AM peak hour and exiting during the PM peak hour. The Project would shift these patterns to nearly balance segment volumes between South San Francisco and San Bruno, and would shift station access patterns at San Bruno Station such that a majority of passengers would exit the station during the AM peak hour and enter the station during the PM peak hour. However, the total number of passengers entering/exiting the station or waiting on the platform would be similar to existing conditions but would occur in a reverse commute direction. As an example, under Project Buildout conditions, the total number of PM station entries would be 926, around 200 more entries than the existing 718 station entries in the AM Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 61 peak hour. In both the AM and PM peak periods, BART trains and platforms at San Bruno Station maintain sufficient capacity to handle these increases in passenger volumes. BART capacity is highly constrained on service segments through the Transbay Tube between Oakland and San Francisco. Based on existing ridership data, around 13 percent of BART riders entering or exiting the system at San Bruno, South San Francisco, and Millbrae Stations have an origin or destination in the East Bay and travel through the Transbay Tube (most stations in the East Bay are greater than 40 minutes away). The Project Buildout is expected to have similar travel patterns, adding approximately 100 to 120 trips to the Transbay Tube during the peak hours. While capacity is highly constrained in these periods, this represents a less than one percent contribution to total ridership on this segment of the system under existing conditions and by extension under cumulative conditions as well. In addition, trips would be spread across multiple trains during each peak hour, with an expected increase of only 15 to 20 riders per train, representing one to two additional passengers in each BART car. Therefore, the Project Buildout and Phase 1 Project would not materially affect BART performance or crowding. Table 4-8 summarizes the Project Buildout’s effect on total activity at San Bruno station, ridership on the segment nearest the Project, and ridership in the Transbay Tube. Table 4-8. Project Buildout Effect on Total Activity at San Bruno BART Station Study Period Direction Project Buildout BART Trip Generation 2019 Passenger Count 2019 + Project Buildout San Bruno BART Station Passenger Volumes AM Entries (Peak) 65 718 783 AM Exits (Reverse Peak) 816 187 1,003 PM Exits (Peak) 105 679 784 PM Entries (Reverse Peak) 678 248 926 San Bruno – South San Francisco Segment AM Northbound (Peak) 65 2,102 2,167 AM Southbound (Reverse Peak) 816 1,267 2,083 PM Southbound (Peak) 105 2,013 2,118 PM Northbound (Reverse Peak) 678 1,073 1,751 Transbay Tube (Embarcadero – West Oakland Segment) AM Westbound (Peak) 122 17,395 17,517 PM Eastbound (Peak) 102 15,839 15,941 Notes: In/out split for BART passengers assumed to be similar to vehicle trip generation. Source: BART, 2019, Fehr & Peers, 2020 Caltrain riders would access the Project via South San Francisco or San Bruno stations, depending on service schedules after completion of the Peninsula Corridor Electrification Project. Trip distribution via Caltrain is expected to roughly mirror existing conditions, with about two-thirds of Project-related travel traveling northbound in the AM peak period and southbound in the PM peak period. This distribution would result Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 62 in approximately 233 northbound passengers during the AM peak period and 195 southbound passengers during the PM peak period. Spread across six trains per hour, per direction, the Project would add an average of about 30 to 40 passengers per train, or about five to six passengers per train car. Upon electrification, Caltrain would have capacity for 5,400 passengers per hour, per direction – about 900 passengers per train operating six trains per hour, per direction. Given the Project Buildout’s contribution to Caltrain capacity would be about four percent or less, it is anticipated that the Project Buildout and Phase 1 Project would have a relatively minor effect on Caltrain capacity. A relatively small share of Project travel is expected to occur via SamTrans – about 70 to 80 peak hour trips, which would roughly translate to five to ten passengers per bus. SamTrans presently has sufficient capacity to handle this demand and is likely to be able to accommodate Project trips in the future. 4.4.4 Bicycle and Pedestrian Analysis The project would add approximately 1,000 to 1,100 pedestrian and bicycle trips to and from the site during the AM and PM peak hours (of which 90 percent would be walking or biking to or from transit). In particular, the Project is likely to add bicycle trips along the Centennial Way Trail, Huntington Avenue, South Linden Avenue, and Sneath Lane, which are designated bicycle routes by the cities of South San Francisco and San Bruno. The Project Buildout would also add vehicle trips along designated bicycle routes and in areas with high levels of pedestrian activity. Such areas would include Huntington Avenue, South Linden Avenue, Sneath Lane, San Bruno Avenue, and the edges of downtown San Bruno and downtown South San Francisco. However, since Project traffic would be distributed across several routes accessing freeway ramps, walking and biking conditions are not expected to be adversely affected by Project Buildout or Phase 1 traffic volumes relative to No Project conditions. 4.4.5 Emergency Vehicle Analysis The Project’s primary potential to affect emergency vehicle access would be through design features that do not fully accommodate emergency vehicles, or through Project-generated vehicle traffic that would cause emergency vehicles to be slowed or unable to access the site or surrounding areas. The Phase 1 Project and Project Buildout would increase vehicular delay on several roadways and at several nearby intersections; however, this delay is not bidirectional, and emergency vehicles retain the ability to utilize other traffic lanes to circumvent traffic congestion. In particular, the San Bruno Police Station at 1177 Huntington Avenue would retain the ability to travel both with and against the flow of vehicle traffic should an emergency response be necessary directly from the station (emergency responses from police vehicles usually occur from the field). In addition, the Project provides an additional route for emergency vehicles to access the Project vicinity through construction of the new intersection at Sneath Lane, Huntington Avenue, and Southline Avenue. Consequently, the Phase 1 Project and Project Buildout are not anticipated to adversely affect emergency vehicle operations. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 63 5. Impacts and Mitigations 5.1 Vehicular Traffic 5.1.1 Vehicle Miles Traveled Impact TRANS-1A: Development of the proposed Phase 1 Project would have a less-than-significant impact on vehicle miles traveled due to the Project’s location, transit-oriented nature, and other characteristics. (Less-than-Significant) Impact TRANS-1B: Development of the proposed Project Buildout would have a less-than-significant impact on vehicle miles traveled due to the Project’s location, transit-oriented nature, and other characteristics. (Less-than-Significant) As documented in Section 4.2, the proposed Project meets the criteria set by the California Governor’s Office of Planning and Research and CEQA statute to establish the presumption of a less-than-significant impact on VMT. Specifically, the Project is an employment center located within ½ mile of a major transit station and high quality transit corridor, with a parking ratio below what would otherwise be required by the City for projects of this type, and Project elements designed to encourage transit use and reduce the number of automobile trips to and from the site. As such, the Phase 1 Project and Project Buildout would have a less- than-significant impact on VMT, and no mitigation is required. Mitigation Measures: None required. Impact TRANS-2A: Development of the proposed Southline Avenue extension under Phase 1 would have a less-than-significant impact on vehicle miles traveled due to its short distance, and nature as a connector rather than a regional roadway facility. (Less- than-Significant) Impact TRANS-2B: Development of the proposed Southline Avenue extension under Project Buildout would have a less-than-significant impact on vehicle miles traveled due to its short distance, and nature as a connector rather than a regional roadway facility. (Less- than-Significant) As documented in Section 4.2, the proposed Southline Avenue extension is not expected to increase VMT as a street extension one quarter mile in length with mostly local circulation effects. Therefore, the Southline Avenue extension associated with the Phase 1 Project and Project Buildout would have a less-than- significant impact on VMT, and no mitigation is required. Mitigation Measures: None required. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 64 5.2 Design Hazards 5.2.1 Geometric Design Hazards Impact TRANS-3A: Development of the proposed Phase 1 Project would not increase hazards to street users due to a design feature or land uses incompatible with the surrounding street network. (Less-than-Significant) Impact TRANS-3B: Development of the proposed Project Buildout would not increase hazards to street users due to a design feature or land uses incompatible with the surrounding street network. (Less-than-Significant) As documented in Section 4.3.1, the Phase 1 Project and Project Buildout include a range of improvements to vehicle, pedestrian, bicycle, and transit infrastructure that would be consistent with design standards and compatible with the intensity of proposed employment uses. Therefore, the Phase 1 Project and Project Buildout would have a less-than-significant impact on design hazards, and no mitigation is required. Mitigation Measure: None required. 5.2.2 Freeway Ramp Queuing Impact TRANS-4A: Development of the proposed Phase 1 Project would not add vehicle trips to existing freeway off-ramp vehicle queues that exceed storage capacity resulting in a potentially hazardous condition, and as such would have a less than significant impact on freeway ramp queuing. (Less-than-Significant) Impact TRANS-4B: Development of the proposed Project Buildout would not add vehicle trips to existing freeway off-ramp vehicle queues that exceed storage capacity resulting in a potentially hazardous condition, and as such would have a less than significant impact on freeway ramp queuing. (Less-than-Significant) As documented in Section 4.4.2, neither the Phase 1 Project vehicle trips nor the Project Buildout vehicle trips would exceed ramp storage capacities at any of the intersections studied, and would not lead to potential hazardous interference with the freeway mainline. Therefore, the Phase 1 Project and Project Buildout would have a less-than-significant impact on freeway ramp queuing, and no mitigation is required. Mitigation Measures: None required 5.2.3 At-Grade Rail Crossings Impact TRANS-5A: Development of the proposed Phase 1 Project would increase vehicle queues beyond available storage at the South Linden Avenue grade crossing but would not exacerbate risk of collisions; therefore, it would have a less than significant impact on at-grade rail crossing hazards. (Less-than-Significant) Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 65 Impact TRANS-5B: Development of the proposed Project Buildout would increase vehicle queues beyond available storage at the South Linden Avenue grade crossing but would not exacerbate risk of collisions; therefore, it would have a less than significant impact on at-grade rail crossing hazards. (Less-than-Significant) The Project would result in substantial increased traffic volumes at the realigned at-grade rail crossing at South Linden Avenue. As discussed in section 4.3.3 this increase in traffic volumes would lengthen vehicle queues across available storage area. However, the synchronization of traffic signals and presence of medians would limit the risk of collisions associated with Project-related traffic. Synchronized traffic signals included in the Project would minimize potential risk of conflicts since vehicles would be flushed out of the rail crossing prior to a train approaching. The inclusion of medians enhances safety by inhibiting vehicles from traveling around crossing gates through provision of a physical barrier to doing so. Therefore, the Project would have a less-than-significant impact on the South Linden Avenue at-grade rail crossing, and no mitigation is required. Mitigation Measure: None required. Impact TRANS-6A: Development of the proposed Phase 1 Project would decrease vehicle volumes, and therefore vehicle queues, at the Scott Street at-grade rail crossing and would not exacerbate risk of collisions, resulting in no impact to the at-grade rail crossing. (Less-than-Significant) Impact TRANS-6B: Development of the proposed Project Buildout would decrease vehicle volumes, and therefore vehicle queues, at the Scott Street at-grade rail crossing and would not exacerbate risk of collisions, resulting in no impact to the at-grade rail crossing. (Less-than-Significant) The Project would result in a net decrease in traffic volumes crossing the Caltrain corridor along Scott Street. As discussed in Section 4.3.3, some vehicle traffic crossing the Caltrain corridor at Scott Street would shift to Southline Avenue, resulting in a net decrease in vehicle volumes and queues on Scott Street. As a result, the Phase 1 Project and Project Buildout would have a less-than-significant impact on the Scott Street at- grade rail crossing, and no mitigation is required. Mitigation Measure: None required. 5.2.4 Traffic Signal Warrant Impact TRANS-7A: Development of the proposed Phase 1 Project would not meet any traffic signal warrants within the Specific Plan area, and as such the Phase 1 Project results in a less than significant impact. (Less-than-Significant) Impact TRANS-7B: Development of the proposed Project Buildout would not meet any traffic signal warrants within the Specific Plan area, and as such the Project Buildout results in a less than significant impact. (Less-than-Significant) Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 66 As discussed in Section 4.3.2, none of the Project’s five unsignalized driveways meet peak hour signal warrants, and the Project provides appropriate pedestrian crossing treatments at unsignalized crossings. As a result, the Phase 1 Project and Project Buildout would have a less-than-significant impact on traffic signal warrants, and no mitigation is required. Mitigation Measure: None required. Impact TRANS-8A: Development of the proposed Phase 1 Project would meet Peak Hour Signal Warrant at the City of San Bruno’s Huntington Avenue/Herman Street/Forest Avenue Intersection; however, conditions would not change materially from existing conditions, and as such the Phase 1 Project results in a less than significant impact at this location. (Less-than-Significant) Impact TRANS-8B: Development of the proposed Project Buildout would meet Peak Hour Signal Warrant at the Huntington Avenue/Herman Street/Forest Avenue Intersection, resulting in a significant impact. (Significant) As documented in Section 4.4.1, the Project would result in a net increase of about 11 PM vehicle trips under Phase 1 conditions and 301 PM peak hour trips under Project Buildout conditions at the intersection of Huntington Avenue/Herman Street/Forest Avenue. This intersection meets CA-MUTCD peak hour signal warrant during the PM peak hour under Existing, 2024 No Project, and 2040 No Project conditions. The addition of Project Buildout traffic would substantially contribute to the need for a signal at this intersection; Phase 1 traffic would not materially change conditions relative to no Project conditions. As such, the Project Buildout would have a significant impact at this location, while Phase 1 would have a less than significant impact. Mitigation Measures: The Project Sponsor should provide a fair share contribution towards implementation of a traffic signal at the intersection of Huntington Avenue/Herman Street/Forest Avenue to alleviate potential conflicts associated with Project Buildout-related traffic. However, the traffic signal is not presently included in a capital improvement or fee program adopted by the City of San Bruno, therefore, the City of San Bruno does not have a plan or mechanism for funding this mitigation and cannot ensure this mitigation occurs will be implemented. Therefore, while the proposed mitigation could reduce the Project Buildout impact on this intersection to a less-than-significant level, because a funding mechanism does not exist, the impact would be remain significant and unavoidable. (Significant and Unavoidable) 5.3 Emergency Vehicle Access Impact TRANS-9A: Development of the proposed Phase 1 Project would not produce a detrimental impact to emergency vehicle access in the study area. (Less-than-Significant) Impact TRANS-9B: Development of the proposed Project Buildout would not produce a detrimental impact to emergency vehicle access in the study area. (Less-than-Significant) Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 67 As documented in Section 4.4.5, the Project would not include design elements that would hinder emergency access, and all roadways and facilities will be designed to accommodate emergency vehicles including fire trucks and fire engines. The Project would result in increased travel times and vehicular delay on Huntington Avenue and Sneath Lane near the Project, particularly for the portion of Sneath Lane between the Project and El Camino Real during the PM peak hour. While this increase in vehicular delay is expected to also affect emergency vehicles, Sneath Lane includes additional right of way in the form of the Class II Bicycle Lane that allows for vehicles to yield to emergency vehicles that have engaged sirens and flashers. Thus, while there may be some delay to emergency vehicles with the Project, it is not expected to adversely affect emergency vehicle access or response times. Therefore, the Phase 1 Project and Project Buildout would have a less than significant impact on emergency vehicle access and no mitigation is required. Mitigation Measures: None required. 5.4 Bicycle, Pedestrian, and Transit Impact TRANS-10A: Development of the proposed Phase 1 Project would not conflict with adopted policies, plans, or programs regarding transit, bicycle, or pedestrian facilities and results in a less than significant impact based on compliance with such plans and policies. (Less-than-Significant) Impact TRANS-10B: Development of the proposed Project Buildout would not conflict with adopted policies, plans, or programs regarding transit, bicycle, or pedestrian facilities and results in a less than significant impact based on compliance with such plans and policies. (Less-than-Significant) As documented in Section 4.1, the Project exhibits consistency with plans, policies, and programs adopted by the City of South San Francisco, City of San Bruno, C/CAG, BART, and MTC. The Project would provide employment near regional transit, would enhance bicycle and pedestrian facilities to support transit access, would connect local street networks, and would include a TDM program that meets City requirements. Therefore, the Phase 1 Project and Project Buildout would not conflict with adopted policies, plans, or programs and would have a less than significant impact. Impact TRANS-11A: Development of the proposed Phase 1 Project would increase travel times for some bus routes, but would not decrease the overall performance of transit service, and as such results in a less than significant impact on transit. (Less-than-Significant) Impact TRANS-11B: Development of the proposed Project Buildout would increase travel times for some bus routes, but would not decrease the overall performance of transit service, and as such results in a less than significant impact on transit. (Less-than- Significant) Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 68 As documented in Section 4.4.3, the Project would increase average transit travel times on SamTrans ECR bus route (and portions of SamTrans routes 140 and 141) by one to three minutes, but is unlikely to affect the route’s performance overall or require additional buses to maintain comparable headways. No other routes operating in the Project vicinity would have increased average transit times due to the Project. The Project would also add transit ridership to BART, SamTrans, and Caltrain, but would not materially contribute to overcrowding. In addition, the Project delivers pedestrian infrastructure designed to enhance access to the SamTrans transit center and BART station. Therefore, the Phase 1 Project and Project Buildout would have a less than significant impact on transit performance and no mitigation is required. Mitigation Measure: None required. Impact TRANS-12A: Development of the proposed Phase 1 Project would not detrimentally affect the performance or safety of bicycle or pedestrian facilities, resulting in a less than significant impact. (Less-than-Significant) Impact TRANS-12B: Development of the proposed Project Buildout would not detrimentally affect the performance or safety of bicycle or pedestrian facilities, resulting in a less than significant impact. (Less-than-Significant) As documented in Section 4.4.4, the Project would not degrade the performance or safety of bicycle or pedestrian facilities. The Project would extend the Centennial Way Trail, enhance bicycle and pedestrian access to the San Bruno BART Station, and provide new bike lane and sidewalk facilities. Therefore, the Phase 1 Project and Project Buildout would have a less than significant impact on bicycle and pedestrian facilities, and no mitigation is required. Mitigation Measure: None required. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 69 6. Partial Circulation Network Alternative The Partial Circulation Network Alternative considers the same Phase 1 and Project Buildout land use and TDM program but with fewer infrastructure changes associated with the Project. Specifically, the Partial Circulation Network Alternative would include a partial buildout of Southline Avenue but omit the new street connection between Huntington Avenue/Sneath Lane and Southline Avenue/Maple Avenue as well as pedestrian and bicycle improvements to enhance access to BART and SamTrans facilities and extend the Centennial Way Trail (referred to as the “Partial Circulation Network Alternative”; see Figure [6-1?] ). This section analyzes the transportation and circulation effects of the Partial Circulation Network Alternative under both the Phase 1 Project and Project Buildout conditions. 6.1 Plan and Policy Consistency Analysis The Partial Circulation Network Alternative would remain consistent with local and regional plans and policies. The Partial Circulation Network Alternative would not implement the connection of Sneath Lane and Southline Avenue, the extension of the Centennial Way Trail, and access improvements to the San Bruno BART Station consistent with adopted plans and policies by the Cities of South San Francisco and San Bruno, C/CAG, BART and MTC. However, the Partial Circulation Network Alternative would not necessarily preclude these changes in the future, and is therefore consistent with applicable plans and policies. The Partial Circulation Network Alternative would remain consistent with regional plans and policies given the Project’s proximity to transit (see Section 4.1). 6.2 VMT Analysis The Partial Circulation Network Alternative would meet OPR’s criteria for a presumption of less than significant VMT impact based on the Project’s proximity to the San Bruno BART Station and the SamTrans ECR route (see Section 4.2). Transit access conditions would be more challenging under the Partial Circulation Network Alternative, although the Partial Circulation Network Alternative would implement a high-density land use in proximity to a high quality transit corridor; include a parking supply below City requirements for comparable projects; and implement a TDM program to achieve a 45 percent mode shift. Without the Southline Avenue extension to Sneath Lane, the Partial Circulation Network Alternative would not realize the slight decrease in VMT associated with more direct trips between San Bruno and the Lindenville District in South San Francisco. However, this would not affect the presumption of less than significant VMT impact for the Project as a whole. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 70 6.3 Site Plan Analysis 6.3.1 Design Hazards The Partial Circulation Network Alternative would not result in any design hazards. As shown in Figure 6-1, Partial Circulation Network Alternative would include limited changes to circulation within the Specific Plan area. The site plan includes the addition of Southline Avenue as an east-west connection between Maple Avenue and South Linden Avenue, the realignment of the South Linden Avenue at-grade rail crossing, and driveways connecting to Southline Avenue, Dollar Avenue, Maple Avenue, South Linden Avenue, and Tanforan Avenue. Southline Avenue would include bike lanes connecting to the Centennial Way Trail, and all new or modified streets would include new sidewalks and curb ramps. Proposed infrastructure within the Specific Plan area would be consistent with design standards and compatible with the intensity of proposed employment uses. The Partial Circulation Network Alternative would not include changes to streets, sidewalks, crosswalks, bicycle facilities, or transit circulation outside of the Specific Plan area other than the changes listed above. The effects of the Partial Circulation Network Alternative are discussed in Section 4.4.4. 6.3.2 Signal Warrant Analysis No driveways would meet peak hour vehicle or pedestrian volume signal warrants under the Phase 1 or Project Buildout Partial Circulation Network Alternatives. Thus, signalization at project driveways and crosswalks would not be required. 6.3.3 At-Grade Rail Crossing Analysis 6.3.3.1 South Linden Avenue At-Grade Rail Crossing With the Partial Circulation Network Alternative, there is potential for queues exceeding available storage for the westbound movements at Southline Avenue and Dollar Avenue under Project Buildout conditions and by extension, Phase 1 conditions. As shown in Table 6-1, queues are expected to exceed storage lengths in the westbound direction crossing the railroad tracks in the AM and PM peak hours. However, by synchronizing the traffic signal with the at-grade crossing, the Project would reduce potential risk of conflicts since vehicles would be provided adequate time to pass through the rail crossing prior to a train approaching. The inclusion of medians at the South Linden Avenue at-grade crossing would also enhance safety by physically prohibiting vehicles from illegally traveling around crossing gates when down. Consequently, the risk of conflicts under either the Phase 1 Project or Project Buildout would not change substantially relative to the existing condition. Therefore, the Partial Circulation Network Alternative would have a less than significant impact on the South Linden Avenue at-grade rail crossing. Project Buildout Partial Circulation Network Site Plan Figure 6-1\\Fpsf03.fpainc.local\data\Projects\2020_Projects\SF20-1089_Southline EIR\Graphics\GIS\MXD\CA_Template_LetterPortrait.mxd Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 72 Table 6-1. Queuing at Linden Avenue At-Grade Rail Crossing – Partial Circulation Network Alternative (2040 Project Buildout) Intersection Movement Storage Space Average Queue Length (ft) 95th Percentile Queue Length (ft) Queue exceeds storage? AM Peak Hour Southline Avenue / Dollar Avenue WBT 80 570 590 Yes Southline Avenue / Dollar Avenue WBL 60 560 580 Yes Linden Avenue/ San Mateo Avenue SBT 450 100 130 No Linden Avenue/ San Mateo Avenue SBL 450 200 240 No PM Peak Hour Southline Avenue / Dollar Avenue WBT 80 230 470 Yes Southline Avenue / Dollar Avenue WBL 60 220 460 Yes Linden Avenue/ San Mateo Avenue SBT 450 190 420 No Linden Avenue/San Mateo Avenue SBL 450 320 390 No 6.3.3.2 Scott Street At-Grade Rail Crossing Without the connection between Sneath Lane and Southline Avenue, the Partial Circulation Network Alternative would increase traffic volumes on the Scott Street at-grade rail crossing. However, queues are not expected to exceed available storage on Scott Street as shown in Table 6-2. Therefore, the Partial Circulation Network Alternative would have a less than significant impact on the Scott Street at-grade rail crossing. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 73 Table 6-2. Queuing at Scott Street At-Grade Rail Crossing – Partial Circulation Network Alternative (2040 Project Buildout) Intersection Movement Storage Space Average Queue Length (ft) 95th Percentile Queue Length (ft) Queue exceeds storage? AM Peak Hour Scott Street / Herman Street WB 360 60 120 No Scott Street / San Mateo Avenue EB 360 60 80 No PM Peak Hour Scott Street / Herman Street WB 360 130 240 No Scott Street / San Mateo Avenue EB 360 40 90 No 6.4 Offsite Transportation Analysis 6.4.1 Signal Warrant Analysis The Partial Circulation Network Alternative would result in Huntington Avenue/Herman Street/Forest Lane intersection meeting the peak hour signal warrant during the PM peak hour for both the Phase 1 and Project Buildout conditions such that a Significant Impact would occur. Phase 1 would add 133 PM peak hour trips to this intersection, while Project Buildout would add approximately 571 PM peak hour trips. Under the Partial Circulation Network Alternative, the addition of Phase 1 and Project Buildout-related trips may exacerbate the risk of collisions at this multi-lane stop-controlled intersection, which experienced eight reported injury collisions between 2014 and 2019 (five vehicle-vehicle collisions, two vehicle-pedestrian collisions, and one-vehicle-bicycle collision).15 6.4.2 Freeway Ramp Queueing Analysis The Partial Circulation Network Alternative would result in queues exceeding the total ramp storage distance to the freeway mainline at one study location (I-280 Northbound Off-Ramp at San Bruno Avenue) under Project Buildout conditions such that a Significant Impact would occur. Under both the Phase 1 and Project Buildout conditions, the Partial Circulation Network Alternative would distribute Project-related vehicle trips across ten freeway ramps for US-101, I-280, and I-380, with slightly more trips using US-101 ramps and slightly fewer trips using ramps to I-380 and I-280. Phase 1 results are shown in Table 6-3, while Project Buildout results are shown in Table 6-4. In addition to the I-280 Northbound Off-Ramp at San Bruno 15 California Statewide Integrated Traffic Records System (SWITRS), 2014-2019, retrieved via the Transportation Injury Mapping System (TIMS) Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 74 Avenue, queues may exceed storage distance at several other ramp approaches under Phase 1 and Project Buildout conditions, but there are no Phase 1- or Project-related trips added to these ramps. Table 6-3. Weekday AM and PM Peak Hour 95th Percentile Queues – Partial Circulation Network Alternative (Phase 1) Approach Lanes Storage Distance (ft) Existing 2024 No Project 2024 Plus Phase 1 (Partial Circulation) Queue Length Queue Length Queue Length AM PM AM PM AM PM 1. I-280 Southbound Off-Ramp at Rollingwood Drive & Sneath Lane Left/Through 1,200 65 190 68 197 77 203 Right 150 65 72 67 62 68 66 2. I-280 Southbound Off-Ramp at San Bruno Avenue* Left 120 197 153 205 158 209 161 Left/Through 840 183 90 190 92 197 96 Through/Right 3,615 Right 80 54 51 58 51 62 57 3. I-280 Northbound Off-Ramp at San Bruno Avenue* Left 230 85 202 89 211 91 207 Through/Left/Right 1,280 334 660 365 701 325 701 4. US-101 Southbound Off-Ramp at San Bruno Avenue* Left 280 112 81 112 84 56 86 Left/Through 960 112 82 112 84 56 86 Right 280 24 130 24 136 24 140 5. US 101 Northbound Off-Ramp at San Bruno Avenue* Left 560 256 345 260 391 295 419 Right (through) 2,400 69 68 93 86 102 103 6. I-380 Westbound Off-Ramp at El Camino Real* Left 980 246 303 248 303 248 303 Right 980 252 834 280 838 296 799 7. I-380 Eastbound Off-Ramp at El Camino Real* Left 520 131 340 135 352 157 355 Through/Left/Right 1,760 96 263 105 287 151 306 Right 330 88 245 96 267 118 277 8. US 101 Southbound Off-Ramp at Airport Boulevard Left 430 208 143 213 166 230 174 Through 720 209 224 220 240 230 254 9. US 101 Southbound Off-Ramp at Produce Avenue Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 75 Approach Lanes Storage Distance (ft) Existing 2024 No Project 2024 Plus Phase 1 (Partial Circulation) Queue Length Queue Length Queue Length AM PM AM PM AM PM Left 620 220 162 182 168 221 202 Right 100 69 40 58 40 59 42 10. US 101 Northbound Off-Ramp at South Airport Boulevard Left/Through 740 473 176 492 188 492 182 Right 740 45 33 46 34 46 34 Notes: Ramps analyzed using Synchro software; * indicates additional analysis with Simtraffic software. Bold type indicates conditions where queue length exceeds storage capacity due to Project-related trips (none applicable). Queues do not take into account downstream spillover from adjacent intersections. Storage distance and queues in feet per lane. Source: Fehr & Peers, 2020 Table 6-4. Cumulative Weekday AM and PM Peak Hour 95th Percentile Queues - Partial Circulation Network Alternative (Project Buildout) Approach Lanes Storage Distance (ft) 2040 No Project 2040 Plus Project (Buildout) 2040 Plus Project Buildout (Partial Circulation) Queue Length Queue Length Queue Length AM PM AM PM AM PM 1. I-280 Southbound Off-Ramp at Rollingwood Drive & Sneath Lane Left/Through 1,200 105 215 118 230 198 254 Right 150 74 91 104 103 356 74 2. I-280 Southbound Off-Ramp at San Bruno Avenue* Left 120 232 179 243 195 239 200 Left/Through 840 221 102 227 120 224 123 Through/Right 3,615 Right 80 68 68 74 79 73 76 3. I-280 Northbound Off-Ramp at San Bruno Avenue* Left 230 93 225 419 240 418 240 Through/Left/Right 1,335 394 818 1,171 778 1,633 801 4. US-101 Southbound Off-Ramp at San Bruno Avenue* Left 280 115 87 65 88 130 91 Left/Through 960 116 87 65 89 130 91 Right 280 26 138 26 138 64 140 5. US 101 Northbound Off-Ramp at San Bruno Avenue* Left/Through 2,600 277 603 2,299 1,040 1,723 1,074 Right 560 324 335 961 498 818 505 Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 76 Approach Lanes Storage Distance (ft) 2040 No Project 2040 Plus Project (Buildout) 2040 Plus Project Buildout (Partial Circulation) Queue Length Queue Length Queue Length AM PM AM PM AM PM 6. I-380 Westbound Off-Ramp at El Camino Real* Left 980 253 212 250 217 257 265 Right 980 331 668 359 637 338 851 7. I-380 Eastbound Off-Ramp at El Camino Real* Left 520 157 294 234 378 178 360 Through/Left/Right 1,760 170 271 271 312 227 328 Right 330 160 252 242 273 207 305 8. US 101 Southbound Off-Ramp at Airport Boulevard Left 430 278 253 360 270 384 245 Through 720 282 307 368 318 392 311 9. US 101 Southbound Off-Ramp at Produce Avenue Left 620 208 182 272 226 280 255 Right 100 63 43 63 45 62 44 10. US 101 Northbound Off-Ramp at South Airport Boulevard Left/Through 740 526 283 514 274 577 302 Right 740 46 39 47 39 591 344 Notes: Ramps analyzed using Synchro software; * indicates additional analysis with Simtraffic software. Bold type indicates conditions where queue length exceeds storage capacity due to Project-related trips. Storage distance and queues in feet per lane. Source: Fehr & Peers, 2020 6.4.3 Transit Performance Analysis Without any changes to transit center access, traffic signals, or added vehicle traffic on Sneath Lane, the Partial Circulation Network Alternative would not substantially affect SamTrans operations at the San Bruno BART transit center compared to Project and No Project conditions. No changes to transit capacity and crowding would occur relative to the Project condition. Therefore, the Partial Circulation Network Alternative would have a less than significant impact on transit performance. 6.4.4 Bicycle and Pedestrian Analysis 6.4.4.1 Effects on BART Station Access The Partial Circulation Network Alternative would not address bicycle and pedestrian connections between the Specific Plan Area and San Bruno BART Station. Instead, bicycle and pedestrian access to BART would occur via existing sidewalks and crosswalks. While these facilities could accommodate the roughly 200 peak hour BART passengers generated by the Phase 1 Project, crowding is expected to occur at existing Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 77 pedestrian facilities with the 800 to 900 peak hour passengers under Project Buildout conditions. Figure 3-1 illustrates a VisWalk simulation of pedestrian crowding at the BART Station entrance under Project Buildout conditions. Specifically, the northwestern curb ramp at the BART Station entrance would be substantially crowded during the AM peak hour, while the northeastern curb ramp would be substantially crowded during the PM peak hour. This crowding may result in a hazardous condition if not all pedestrians are accommodated on the sidewalk, and for interactions between pedestrians and bicyclists traveling to or from the Centennial Way Trail. The design and operations of the traffic signal and crosswalks contribute to crowding due to the relatively long wait times for pedestrians crossing the street and single marked crosswalk across Huntington Avenue. This configuration may prompt some pedestrians to cross in the unmarked crosswalk on the southern side of the intersection rather than waiting to cross to the marked northern crosswalk. The unmarked southern crosswalk has a longer crossing distance that is less likely to be accomplished in the allocated walk time and may leave some pedestrians crossing against traffic on Huntington Avenue or waiting in the median. The combination of limited sidewalk capacity, auto-oriented signal operations, and crosswalk design poses a potentially hazardous condition with the addition of trips by pedestrians and bicyclists traveling to and from the San Bruno BART Station under Project Buildout conditions with the Partial Circulation Network Alternative such that a Significant Impact would occur. Figure 6-2. Pedestrian Space during AM and PM Peak Hours, Project Buildout with Partial Circulation Network Alternative 6.4.4.2 Other Effects Under both the Phase 1 and Project Buildout conditions, the Partial Circulation Network Alternative would increase vehicle trips along designated bicycle routes and in areas with high levels of pedestrian activity. Such areas would include Herman Avenue, South Linden Avenue, Sneath Lane, San Bruno Avenue, Spruce Avenue, and the edges of downtown San Bruno and downtown South San Francisco. However, since Project traffic would be distributed across several routes accessing freeway ramps, walking and biking conditions Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 78 are not expected to be adversely affected by the Partial Circulation Network Alternative relative to No Project conditions. 6.4.5 Emergency Vehicle Analysis Neither the Phase 1 nor Project Buildout conditions under the Partial Circulation Network Alternative are anticipated to substantially affect emergency vehicle operations relative to the No Project conditions. The proposed site plan fully accommodates emergency vehicles and would not include design features that would cause emergency vehicle to be slowed or unable to access the site or surrounding areas. 6.5 Impacts and Mitigations 6.5.1 Vehicular Traffic 6.5.1.1 Vehicle Miles Traveled Impact TRANS-13A: Development of the proposed Partial Circulation Network Alternative would have a less-than-significant impact on vehicle miles traveled, under Phase 1 conditions, due to the Project’s location, transit-oriented nature, and other characteristics. (Less-than-Significant) Impact TRANS-13B: Development of the proposed Partial Circulation Network Alternative would have a less-than-significant impact on vehicle miles traveled, under Project Buildout conditions, due to the Project’s location, transit-oriented nature, and other characteristics. (Less-than-Significant) As documented in Section 6.2, the Partial Circulation Network Alternative would not change the Project’s proximity to transit and presumption of less than significant impact to VMT. While the Partial Circulation Network Alternative would not realize the slight decrease in VMT associated with more direct trips between San Bruno and the Lindenville District in South San Francisco, the Phase 1 Project and Project Buildout under the Partial Circulation Network Alternative would have a less-than-significant impact on VMT, and no mitigation is required. Mitigation Measures: None required. 6.5.2 Design Hazards 6.5.2.1 Geometric Design Hazards Impact TRANS-14A: Development of the proposed Partial Circulation Network Alternative would not increase hazards to street users, under Phase 1 conditions, due to a design feature or land uses incompatible with the surrounding street network. (Less-than- Significant) Impact TRANS-14B: Development of the proposed Partial Circulation Network Alternative would not increase hazards to street users, under Project Buildout conditions, due to a design Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 79 feature or land uses incompatible with the surrounding street network. (Less-than- Significant) The Partial Circulation Network Alternative would provide onsite circulation changes consistent with design standards, but would not provide access improvements to the San Bruno BART Station under the Phase 1 Project or Project Buildout. Therefore, the Partial Circulation Network Alternative under both Phase 1 Project and Project Buildout conditions would have a less-than-significant impact on design hazards, and no mitigation is required. Mitigation Measure: None required. 6.5.2.2 Freeway Ramp Queuing Impact TRANS-15A: Development of the proposed Partial Circulation Network Alternative would not add vehicle trips to existing freeway off-ramp vehicle queues, under Phase 1 conditions, that exceed storage capacity resulting in a potentially hazardous condition, and as such would have a less than significant impact on freeway ramp queuing. (Less-than-Significant) Impact TRANS-15B: Development of the proposed Partial Circulation Network Alternative would cause vehicle queues, under Project Buildout conditions, to exceed storage capacity at one freeway ramp (I-280 Northbound Off-Ramp at San Bruno Avenue) resulting in a significant impact. (Significant) As documented in Section 6.4.2, the Partial Circulation Network Alternative does not cause vehicle trips associated with the Phase 1 Project to exceed ramp storage capacities at any ramps studied; however, queues would exceed ramp storage capacity due to Project-related travel at one study location (I-280 Northbound Off-Ramp at San Bruno Avenue) under Project Buildout conditions (shown in Table 6-4). As such, the Partial Circulation Network Alternative would have a significant impact at this location at Project Buildout, while Phase 1 would have a less than significant impact. Mitigation Measures: Although the purpose of the Partial Circulation Network Alternative is to evaluate a condition where the extension of Southline Avenue to Sneath Lane does not occur, this street extension as included in the Proposed Project would mitigate ramp queueing conflicts associated with Project Buildout- related traffic. However, without the direct implementation by the Project Sponsor, no plan or funding mechanism exists to implement this mitigation since it is not presently included in a capital improvement or fee program adopted by the City of South San Francisco or the City of San Bruno where the mitigation is jointly located. Therefore, while the proposed mitigation could reduce the Partial Circulation Network Alternative impact to a less-than-significant level, because a funding mechanism does not exist, the impact would remain significant and unavoidable. There are no other feasible mitigation measures. (Significant and Unavoidable) Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 80 6.5.2.3 At-Grade Rail Crossings Impact TRANS-16A: Development of the proposed Partial Circulation Network Alternative would increase vehicle queues beyond available storage at the South Linden Avenue grade crossing, under Phase 1 conditions, but would not exacerbate risk of collisions; therefore, it would have a less than significant impact on at-grade rail crossing hazards. (Less-than-Significant) Impact TRANS-16B: Development of the proposed Partial Circulation Network Alternative would increase vehicle queues beyond available storage at the South Linden Avenue grade crossing, under Project Buildout conditions, but would not exacerbate risk of collisions; therefore, it would have a less than significant impact on at-grade rail crossing hazards. (Less-than-Significant) The Partial Circulation Network Alternative would result in increased traffic volumes at the realigned at- grade rail crossing at South Linden Avenue under Phase 1 Project and Project Buildout conditions. However, Project-related crossing improvements would limit the risk of collisions associated with increased traffic, consistent with the Phase 1 and Project site plans. Therefore, the Partial Circulation Network Alternative under the Phase 1 Project and Project Buildout conditions would have a less-than-significant impact on the South Linden Avenue at-grade rail crossing, and no mitigation is required. Mitigation Measure: None required. Impact TRANS-17A: Development of the proposed Partial Circulation Network Alternative would not increase vehicle queues, under Phase 1 conditions, beyond available storage at the Scott Street at-grade rail crossing and would not exacerbate risk of collisions, resulting in no impact to the at-grade rail crossing. (Less-than-Significant) Impact TRANS-17B: Development of the proposed Partial Circulation Network Alternative would not increase vehicle queues, under Project Buildout conditions, beyond available storage at the Scott Street at-grade rail crossing and would not exacerbate risk of collisions, resulting in no impact to the at-grade rail crossing. (Less-than- Significant) The Partial Circulation Network Alternative would result in an increase in vehicle traffic across the at-grade rail crossing at Scott Street, but would not increase vehicle queues beyond available storage under the Phase 1 or Project Buildout conditions. As a result, the Partial Circulation Network Alternative, under Phase 1 Project and Project Buildout conditions, would have a less-than-significant impact on the Scott Street at- grade rail crossing, and no mitigation is required. Mitigation Measure: None required. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 81 6.5.2.4 Traffic Signal Warrant Impact TRANS-18A: Development of the proposed Partial Circulation Network Alternative would not meet any traffic signal warrants within the Specific Plan area, under Phase 1 conditions, and as such the Phase 1 Project results in a less than significant impact. (Less-than-Significant) Impact TRANS-18B: Development of the proposed Partial Circulation Network Alternative would not meet any traffic signal warrants within the Specific Plan area, under Project Buildout conditions, and as such the Project Buildout results in a less than significant impact. (Less-than-Significant) None of the Project’s five unsignalized driveways meet peak hour signal warrants under Phase 1 or Project Buildout conditions with the Partial Circulation Network Alternative as described in Sections 6.3.2 and 6.4.1. The Project would provide appropriate pedestrian crossing treatments at these unsignalized crossings. As a result, the Partial Circulation Network Alternative under both Phase 1 Project and Project Buildout conditions would have a less-than-significant impact on traffic signal warrants, and no mitigation is required. Mitigation Measure: None required. Impact TRANS-19A: Development of the proposed Partial Circulation Network Alternative would meet Peak Hour Signal Warrant at the Huntington Avenue/Herman Street/Forest Avenue Intersection, under Phase 1 conditions, resulting in a significant impact. (Significant) Impact TRANS-19B: Development of the proposed Partial Circulation Network Alternative would meet Peak Hour Signal Warrant at the Huntington Avenue/Herman Street/Forest Avenue Intersection, under Project Buildout conditions, resulting in a significant impact. (Significant) As documented in Section 6.4.1, the Partial Circulation Network Alternative would result in a net increase of about 133 PM vehicle trips under Phase 1 conditions and 571 PM peak hour trips under Project Buildout conditions at the intersection of Huntington Avenue/Herman Street/Forest Avenue. This intersection meets CA-MUTCD peak hour signal warrant during the PM peak hour under Existing, 2024 No Project, and 2040 No Project conditions. The addition of Phase 1 and Project Buildout traffic would substantially contribute to the need for a signal at this intersection. As such, the Partial Circulation Network Alternative under both the Phase 1 and Project Buildout conditions would have a significant impact at this location. Mitigation Measures: The Project Sponsor should provide a fair share contribution towards implementation of a traffic signal at the intersection of Huntington Avenue/Herman Street/Forest Avenue to alleviate potential conflicts associated with Project Buildout-related traffic. However, the traffic signal is not presently included in a capital improvement or fee program adopted by the City of San Bruno, therefore, the City of San Bruno does not have a mechanism for funding this mitigation and cannot ensure this Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 82 mitigation occurs will be implemented. Therefore, while the proposed mitigation could reduce the Project Buildout impact on this intersection to a less-than-significant level, because a funding mechanism does not exist, the impact would be remain significant and unavoidable. (Significant and Unavoidable) Emergency Vehicle Access Impact TRANS-20A: Development of the proposed Partial Circulation Network Alternative would not produce a detrimental impact to emergency vehicle access in the study area, under Phase 1 conditions. (Less-than-Significant) Impact TRANS-20B: Development of the proposed Partial Circulation Network Alternative would not produce a detrimental impact to emergency vehicle access in the study area, under Project Buildout conditions. (Less-than-Significant) As documented in Section 6.4.5, the Partial Circulation Network Alternative would not include design elements that would hinder emergency access, and all roadways and facilities will be designed to accommodate emergency vehicles. Therefore, the Partial Circulation Network Alternative under the Phase 1 and Project Buildout conditions would have a less than significant impact on emergency vehicle access and no mitigation is required. Mitigation Measures: None required 6.5.3 Bicycle, Pedestrian, and Transit Impact TRANS-21A: Development of the proposed Partial Circulation Network Alternative would not conflict with adopted policies, plans, or programs regarding transit, bicycle, or pedestrian facilities, under Phase 1 conditions, and results in a less than significant impact based on compliance with such plans and policies. (Less-than-Significant) Impact TRANS-21B: Development of the proposed Partial Circulation Network Alternative would not conflict with adopted policies, plans, or programs regarding transit, bicycle, or pedestrian facilities, under Project Buildout conditions, and results in a less than significant impact based on compliance with such plans and policies. (Less-than- Significant) As documented in Section 6.1, the Partial Circulation Network Alternative would not implement the connection of Sneath Lane and Southline Avenue, the extension of the Centennial Way Trail, and access improvements to the San Bruno BART Station consistent with adopted plans and policies by the Cities of South San Francisco and San Bruno, C/CAG, BART and MTC. However, the Alternative would not necessarily preclude these changes in the future, and therefore the Partial Circulation Network Alternative under the Phase 1 Project and Project Buildout conditions would not conflict with adopted policies, plans, or programs and would have a less than significant impact. Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 83 Impact TRANS-22A: Development of the proposed Partial Circulation Network Alternative would increase travel times for some bus routes, under Phase 1 conditions, but would not decrease the overall performance of transit service, and as such results in a less than significant impact on transit. (Less-than-Significant) Impact TRANS-22B: Development of the proposed Partial Circulation Network Alternative would increase travel times for some bus routes, under Project Buildout conditions, but would not decrease the overall performance of transit service, and as such results in a less than significant impact on transit. (Less-than-Significant) As documented in Section 6.4.3, the Partial Circulation Network Alternative would not substantially affect transit operations or contribute to transit overcrowding. Therefore, the Partial Circulation Network Alternative under both Phase 1 and Project Buildout conditions would have a less than significant impact on transit performance and no mitigation is required. Mitigation Measure: None required. Impact TRANS-23A: Development of the proposed Project Buildout Partial Circulation Network Alternative would not decrease the performance and safety of bicycle and pedestrian facilities near the Project under Phase 1 conditions, resulting in a less- than-significant impact. (Less-than-Significant) Impact TRANS-23B: Development of the proposed Project Buildout Partial Circulation Network Alternative would decrease the performance and safety of bicycle and pedestrian facilities near the Project under Project Buildout conditions, resulting in a significant impact. (Significant) As documented in Section 4.4.4, the Project Buildout Partial Circulation Network Alternative would result in substantial crowding to pedestrian and bicycle facilities near the San Bruno BART Station entrance. While existing facilities could accommodate Phase 1 pedestrian volumes, existing sidewalk, crosswalk, and signal facilities are insufficient to accommodate Project Buildout pedestrian volumes, and may pose a hazardous condition due to crowding. Therefore, the Partial Circulation Network Alternative would have a less than significant impact under Phase 1 conditions, while the Partial Circulation Network Alternative would have a significant impact under Project Buildout conditions. Mitigation Measure: Although the purpose of the Partial Circulation Network Alternative is to evaluate a condition where the extension of Southline Avenue to Sneath Lane and associated changes to pedestrian and bicycle infrastructure do not occur, the implementation of pedestrian improvements at the San Bruno BART Station entrance as included in the Proposed Project would alleviate this potentially significant impact under Project Buildout conditions. Pedestrian improvements would include adding a bulbout, curb ramps, and marked high-visibility crosswalk on the southern leg of the intersection, a high-visibility crosswalk on the northern leg of the intersection, and retiming the signal to include pedestrian recall. However, without the direct implementation by the Project Sponsor, no funding mechanism exists to implement this Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 84 mitigation since it is not presently included in a capital improvement or fee program adopted by the City of South San Francisco or City of San Bruno where the mitigation is jointly located. Therefore, while the proposed mitigation could reduce the Partial Circulation Network Alternative impact to a less-than- significant level, because a funding mechanism does not exist, the impact would remain significant and unavoidable. There are no other feasible mitigation measures. (Significant and Unavoidable) Southline Specific Plan Transportation Impact Analysis June 2021 17620.001 4834-6937-3933.3 85 Appendix: VMT Totals for Greenhouse Gas Analysis The following table summarizes VMT totals for use in greenhouse gas analysis. The C/CAG Model estimates VMT and auto mode share based on regional travel behavior and proximity to transit. However, the model outputs do not fully reflect the implementation of the Project’s TDM program as required by city ordinance (most notably subsidized transit passes), and does not take into account active transportation facilities like the Centennial Way Trail as well as access improvements between the project and regional transit stations. It is anticipated that the project’s TDM program would result in a 23 percent reduction in VMT over the C/CAG Model estimates based on these factors. Appendix Table: VMT Totals for GHG Analysis Scenario TAZ Total VMT Total Project VMT (Drive Alone Mode Share) Total Project VMT with TDM Program Existing 258,500 - - Existing Plus Phase I 362,200 103,800 (71%) 79,900 (55%) 2024 260,000 - - 2024 Plus Phase I 363,800 103,800 (71%) 79,900 (55%) 2040 No Project 264,100 - - 2040 Plus Project Buildout 663,500 399,400 (71%) 307,500 (55%)