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Home My WebLink AboutRevision Draft Supplemental Terrabay Specific Plan 08-01-1996 --- "- REVISIONS TO THE DRAFT SUPPLEMENTAL ENVIRONMENTAL IMPACT REPORT FOR THE PROPOSED TERRABA V SPECIFIC PLAN AND DEVELOPMENT AGREEMENT EXTENSION REVISED TRANSPORTATION IMPACT AND MITIGATION FINDINGS SCH Number: 95092027 Prepared for the CITY OF SOUTH SAN FRANCISCO by WAGSTAFF AND ASSOCIATES Urban and Environmental Planners in association with The Crane Transportation Group, Transportation Planners and Engineers August 1996 WP511548IFSEIF/lCOVER-2;S48 T errabay Project City of South San Francisco August 29. 1996 Table 1 PROJECT SUMMARY DATA Revised Draft SEIR - Table 1 Page II J .../ PROJECT NAME: SITE LOCATION: SITE AREA AND r PARCELlZATION: CURRENT GENERAL PLAN DESIGNATION: CURRENT ZONING: EXISTING LAND USE: PROPOSED LAND USE: CIRCULATION: REQUESTED APPROVALS: APPLICANT: PROPERTY OWNER: Terrabay Specific Plan and Development Agreement Extension On the lower southeastern slopes of San Bruno Mountain west of Bayshore Boulevard and north of Hillside Boulevard and Sister Cities Boulevard in the city of South San Francisco. Assessor's Parcel Numbers Approximate Acreaae Book 007; Blocks 590, 600, 611, 332 (total) 612,620,630,641,642,650;all parcels inclusive J --' Planned Commercial, Low-Density Residential, Medium Density Residential, and Open Space T errabay Specific Plan District Primarily open space, partially graded with some improvements installed. The applicant is proposing phased residential and commercial development in accordance with the approved T errabay Specific Plan and development agreement. Phase I, currently under construction, consists of 125 single family detached homes, 168 town homes and related community facilities and infrastructure. The ultimate characteristics and timing of subsequent phases " and III are more conceptual. The specific plan provides for Phase " development of up to an additional 428 residential units and Phase III development of up to 44 acres of commercial uses. Access to Phase I is provided via one connection to Hillside Boulevard opposite Jefferson Street. Phase I intemal circulation is via one public street and several private roads. Phase II access would be at one connection to Sister Cities Boulevard; internal circulation would be via one public street and several private roads. Phase III access would be at Bayshore Boulevard; Phase 11\ internal circulation would be expected to be served by a single private road. The applicant is requesting extension of the termination dates of the T errabay Specific Plan and development agreement to allow for completion of Phase I development of 125 single family detached homes, 168 town homes and community facilities, and eventual development of specific plan Phases II and III. SunChase G.A.. Callfomla I, Inc. SunChase G.A. California I, Inc. SOURCE: Wagstaff and Associates, November 1995. WP511548IFSEIRlTAS1-REV.S48 REVISIONS TO THE DRAFT SUPPLEMENTAL ENVIRONMENTAL IMPACT REPORT FOR THE PROPOSED TERRABA Y SPECIFIC PLAN AND DEVELOPMENT AGREEMENT EXTENSION REVISED TRANSPORTATION IMPACT AND MITIGATION FINDINGS SCH Number: 95092027 Prepared for the CITY OF SOUTH SAN FRANCISCO by WAGSTAFF AND ASSOCIATES Urban and Environmental Planners in association with The Crane Transportation Group, Transportation Planners and Engineers August 1996 WP51 1548IFSEJRl co VER.2. 548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR Preface Page iii PREFACE A. PROJECT DESCRIPTION AND BACKGROUND The Terrabay project is a phased residential and commercial development proposed for location on the lower slopes of San Bruno Mountain in the city of South San Francisco. In 1982. the City of South San Francisco certified an environmental impact report (EIR) and adopted a specific plan for the Terrabay project. A development agreement for the project was executed by the city and applicant in 1988. The applicant is now requesting from the city a 1 a-year extension of the specific plan and development agreement entitlements, which are currently due to expire on February 14, 1997. For the requested entitlement extensions. the city has determined that compliance with California Environmental Quality Act (CEQA) shall be achieved by preparation of a supplement to the certified 1982 EIR, Le., a supplemental EIR, pursuant to CEQA Section 15163, which describes any substantive changes in the project environmental information which have occurred since preparation of the 1982 EIR. A Draft Supplemental Environmental Impact Report (DSEIR) for the Terrabay Specific Plan and Development Agreement Extension was distributed for public review and comment (and public notice of the availability of the DSEIR was published) on January 5, 1996. Before the required 45-day public review period on the DSEIR ended, the South San Francisco City Council extended the public review period by 30 days to March 20, 1996. Comments on the DSEIR were receIved in the form of: (1) public testimony at a Planning Commission public hearing on the DSEIR held on February 1, 1996; and (2) letters and memoranda submitted to the city during the 75-day public review period. A Final SEIR document has been prepared which includes responses to all substantive comments received by the city during the 75-day public review period on the DSEIR, plus a set of DSEIR errata incorporating all revisions made to the DSEIR in response to comments received. B. NEED FOR RECIRCULATION OF TRANSPORTATION FINDINGS Most of the comments received by the city on the January 1996 DSEIR, and the responses to those comments. merely clarify, amplify, or make insignificant changes to the DSEIR. However, formulation of an adequate response to some of the comments pertaining to the DSEIR transportation section has necessitated a revised analysis of certain traffic impacts. It has been determined by the city that some of these revised traffic analyses findings constitute WPS11S48IFSEIRIPREFACES48 T errabay Project City of South San Francisco August 29. 1996 Revised Draft SEtR Preface Page Iv the addition of significant new information to the SEIR--Le., new significant impacts and changes in the severity of certain SEIR-identified impacts. Section 15088.5(a) of the CEOA Guidelines stipulates that, "A lead agency is required to recirculate an EIR when significant new information is added to the EIR after public notice is given of the availability of the draft EIR for public review...but before certification." Significant new information requiring recirculation can include, for example: · a new significant impact not considered in the DSEIR; · a substantial increase in the severity of a DSEIR-identified environmental impact unless new mitigation measures or an alternative are adopted that reduce the impact to a level of insignificance; or · a new alternative or feasible mitigation measure considerably different from those previously analyzed in the DSEIR which has not been adopted by the project proponents. Therefore, in conformance with this section of the CEOA Guidelines, the revised DSEIR transportation section is included herein and has been recirculated on August 30, 1996 for an additional 45-day public review and comment period. Because those revisions involving significant new information are limited to the transportation section of the DSE1R, only the modified transportation section and supporting technical appendix have been recirculated (CEOA Guidelines section 15088.5(c)). The 45-day public review period for the revised DSEIR transportation section ends on October 13, 1996. C. SUMMARY OF SIGNIFICANT TRANSPORTATION IMP ACT AND MITIGATION REVISIONS 1. Revised Transportation Impact Analysis The revisions of the DSEIR transportation analysis that resulted in significant new information requiring recirculation of the transportation section were undertaken in response to comments received on the DSEIR that questioned the year 2010 Base Case traffic projections used in the analysis. The comments noted that the East of 101 Area Plan EIR 2010 Base Case traffic projections upon which the Terrabay DSEIR traffic analysis was based assumed a 20 percent reduction in trip generation from the East of 101 planning area due to the Bay Area Air Quality Management District (BAAQMD) imposed employer-based trip reduction rule. The comment points out that this BAAQMD rule has since been invalidated by state legislative action and, consequently, the DSEIR 2010 traffic projections are low and the project transportation impacts understated. In response, the DSEIR 2010 traffic impact analysis has been revised herein to eliminate the BAAOMD trip reduction rule based 20 percent reduction in peak period trip generation assumed in the East of 101 Area Plan EIR 2010 traffic projections. (The East of 101 Area WP511548IFSEIRIPREFACE548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR Preface Page v Plan EIR year 2000 projections used in the DSEIR traffic analysis did not include a 20 percent reduction for the BAAOMD trip reduction rule. Thus, there has been no change to the DSEIR analyses for year 2000 Base Case and year 2000 Base Case plus project Phase I scenarios.) In addition, based on additional considerations which are explained in the revised transportation section, including information provided by the Multi-City Transportation System Management (TSM) Agency, the DSEIR transportation impact mitiaation section has been revised to include a 12 percent reduction in Base Case and Base Case Plus Project peak period trip generation through voluntary continuation of TSM measures to reduce auto use. Certain other changes in the DSEIR transportation section were also made in response to various public review period comments received (e.g., use of newly available recent traffic counts for selected locations to supplement the ba~e case traffic projections). These other changes, however, merely clarify or make what are ultimately insignificant changes in the transportation analysis conclusions. All text revisions to the transportation section in response to public comments and as a result of the revised transportation analysis are indicated by an "r" in the left margin next to the revised line. 2. New Transportation Impact Flndlnas Reaulrlna Recirculation The revised transportation analysis identified the fOllowing new unavoidable significant adverse ImpactuLe., an impact which cannot be mitigated to a less than significant level even after implementation of all feasible mitigation. It has been determined that this new unavoidable significant impact conclusion warrants recirculation of the DSEIR transportation section under CEOA Guidelines Section 15088.5. This new unavoidable significant adverse impact is due to a substantial deterioration in projected 2010 Base Case traffic operations which it was determined could not be sufficiently offset (to less than significant levels) by the TSM mitigation measures identified in the analysis. (Caltrans has no plans to add additional travel lanes to the segment of US 101 through and just north of South San Francisco by the year 2010.) US 101 Freeway (Supplemental Impact T-15) Even with successful future implementation of TSM measures, full buildout of project Phases I, II and III would result in an approximately three to four percent increase in already unacceptable Base Case conditions (LOS F) on the mainline US 101 freeway segments north of Sierra Point and between the Oyster Point interchange and the South Airport Boulevard interchange. In addition to the new "unavoidable" significant adverse impact described above, the revised transportation analysis also identified the following three new significant project impacts, which could be reduced to less than significant levels by recommended mitigations. However, since these impacts are mitigated, they do not in and of themselves require recirculation. WP5115481FSEIRIPREFACE.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR Preface Page vi (1) Sister Cities Boulevard/Oyster Point Boulevard/Bayshore Boulevard/Airport Boulevard (Supplementallmpsct T-5). In the year 2010 AM peak hour, project Phase I traffic would result in more than a two percent increase in traffic volume at this intersection, which would already be experiencing unacceptable LOS F Base Case operation without the project, and thus would represent a significant adverse project impact. However, this impact could be reduced to a level of insignificance by SEIR-recommended mitigation, requiring project Phase I fair-share contribution towards the flyover off-ramp. (2) US 101 Southbound Off-ramp to Bayshore Boulevard (Supplemental Impact T-16). In the year 2010 PM peak hour, traffic from buildout of Phases I, II and III would result in more than a two percent increase in traffic volume at this intersection, which would already be experiencing unacceptable LOS E Base Case operation without the project, and thus would represent a significant adverse project impact. However, this impact could be reduced to a level of insignificance by SEIR-recommended mitigation, requiring a fair-share contribution from each project phase towards signalization, widening the off- ramp to provide second approach and departure lanes, and widening Bayshore Boulevard to provide second northbound approach and departure lanes. With a flyover off-ramp in operation, only signalization and widening of the off-ramp to provide second approach and departure lanes would be required. (3) US 101 Northbound On-ramp from Oyster Point Boulevard (Supplements/Impact T-18). In the year 2010 PM peak hour, traffic from full buildout of project Phases I, II and III would result in more than a two percent increase in traffic volume at this freeway ramp, which would already be over capacity under Base Case conditions without the project, and thus would represent a significant adverse project impact. However, this impact could be reduced to a level of insignificance by SEIR-recommended mitigation, requiring a fair-share contribution by each project phase towards the addition of a second lane to the on-ramp. WP511548IFSEIRIPREFACE,548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 89 c. TRANSPORTATION This SEIR section reevaluates project impacts on traffic conditions on roadways in the project vicinity. Existing traffic conditions on the local roadway network and future conditions without the project are first described. The traffic impact and mitigation findings of the 1982 EIR are also summarized. The section then describes changes in existing and projected traffic conditions that have occurred since the 1982 EJR, including the recent construction of the Oyster Point interchange and other new roadway improvements, identifies impacts of the project and project-plus-cumulative development in the area on these current roadway system conditions, and recommends roadway improvements necessary to mitigate these updated impact expectations. The findings in this section were developed by the SEIR traffic engineer, Crane Transportation Group. Local transportation system conditions are described for the following scenarios: r . Existing (after construction of the new Oyster Point interchange); . year 2000 Base Case (anticipated year 2000 traffic conditions without the project); . year 2010 Base Case (anticipated year 2010 traffic conditions without the project);' . year 2000 Base Case plus Phase I (anticipated year 2000 traffic conditions with project Phase I; . year 2010 Base Case plus Phases I, /I and 11/ (anticipated year 2010 conditions with project Phases I, II and III). 1. SETTING a. Protect Area Circulation Network Substantial post-1982 changes have been made in the project area circulation network considered in the 1982 EIR. With respect to regional freeway access, the Oyster Point interchange has been recently reconstructed and the Sierra Point interchange and associated 1 For the future year scenarios, the following conditions have also' been assumed: . Wherever a new signal is warranted by projected traffic conditions at study intersections, it has been assumed in place. . Roadway and intersection geometries have been assumed to remain the same from 2000 to 2010 unless specifically stated otherwise. All specific future roadway improvements needed as a mitigation are listed in section 2.c, Changes in Mitigation Findings. WP51 \548\FSE/R\/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 90 Bayshore Boulevard connectors have been constructed. With respect to the local roadway network, several of the mitigations identified in the 1982 EIR and subsequently incorporated into the Terrabay Specific Plan and development agreement have been completed as part of the Phase I roadway improvements. Additional improvements were completed as part of the Oyster Point interchange reconstruction project or other projects in the vicinity. These roadway improvements and changes in traffic controls include: . construction of Sister Cities Boulevard (referred to as the Hillside Extension in the 1982 EIR) between its intersections with Hillside Boulevard and Bayshore Boulevard; r . widening of Hillside Boulevard (renamed Hillside Boulevard Extension) and creation of r local traffic lanes and a landscaped buffer separating local access movements (along r Hillside Boulevard) from higher speed through traffic along Hillside Boulevard Extension between Sister Cities Boulevard and Lincoln Street (the segment fronting the project site); · signalization of intersections at the new Oyster Point interchange and the Hillside r Boulevard Extension/Jefferson Street-South San Francisco Drive, Hillside Boulevard/ Sister Cities Boulevard, Sister Cities Boulevard/South San Francisco Drive and Sister r Cities Boulevard/Airport Boulevard/Bayshore Boulevard intersections; and r . removal of the existing stop signs for Hillside Boulevard Extension traffic at the Hillside r Boulevard Extension/Kearny Street and Hillside Boulevard Extension/Irving Street intersections. A newall-way stop sign was installed at the Hillside Boulevard/Lincoln Street intersection to permit vehicles to exit Lincoln Street under conditions of heavy r truck traffic, high speeds, and limited line-of-sight to the west along Hillside Boulevard at this location. In addition, existing and projected future traffic volumes in the vicinity of the project are higher than those in the 1982 EIR due primarily to greater than anticipated development in the East r of 101 area, and in Brisbane. Traffic analyses performed for other projects in the vicinity indicate increasing traffic volumes and worsening operations, with several intersections performing poorly. Future Base Case traffic volume projections used in this SEIR traffic analysis are based on traffic volume projections in the East of 101 Area Plan Draft EIR and Brisbane General Plan Circulation Element. The network of freeways, arterials, and local streets serving the project area is diagrammed on Figure 6 and described below. (1) Reaional Freeway Access u.s. Highway 101 (US 101) is the principal freeway providing access to the project area. US 101 has eight travel lanes through South San Francisco with auxiliary lanes provided between interchanges where the on-ramp and off-ramp have a common transition area. Access to US 101 in the project area is provided by the new Oyster Point interchange and by on- and off- ramps connecting to Bayshore Boulevard (to the north) and Airport Boulevard (to the south). WP51 \548\FSEIRI/V-C-REV.548 -ell _sc. o ell!; _eIl;:a .- .. c::l U l:: tnr'O ----- P^ III ap!slI!H -0 > c:l - ~ .MV anbqna - .. ~ III >. o 101 .S.O .P^Ul aJOqsh'llg W ....J <( () C/') ~ f- a ~ ~ a: <( Cl z ::> a c:c w f- U5 f- o W ..., a a: a.. , . . -- I l ------, ~ I',---J ~ , I ~ I ... >1 i--J l ! -.. ~ - .P^Ul lJod.Iw . 1 S UOSJaJjaf ' c!S c ~ ~ ,a.l \ t ~ ~ . .~<: ..l: ""' """ -0' ...... c.,:) <: ..... Q f::E =l-'I ~~ ~rJ:J el>" rJ:J >" <: ~ Q <: o ~ ~ <: u o ~ ~ 1:1 Z ~ go e C!J c: .2 ;;; 1: ~ ~ I- ~ III U Iii l) a: ;:) o Vl VI ~ ] T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 92 The new Oyster Point interchange was not considered in the 1982 EIR traffic analysis. The interchange provides on-ramp connections to both north and southbound US 101 as well as a northbound off-ramp. The northbound off-ramp and southbound on-ramp connect to a common signalized intersection with Dubuque Avenue on the east side of the freeway, just south of the Dubuque Avenue connection to Oyster Point Boulevard. The northbound on- ramp extends northerly as the fourth leg of the signalized Oyster Point Boulevard/Dubuque Avenue intersection. Southbound US 101 traffic accesses the project area via a stop sign- controlled off-ramp connecting to Bayshore Boulevard just north of the site. The southbound off-ramp is designed in a "scissors" configuration, including a two-way stop with northbound Bayshore Boulevard (see Figures 6 and 7). Southbound Bayshore Boulevard traffic is not stop sign-controlled at this location; rather, it has a separate travel lane, as does off-ramp traffic departing the all-way stop intersection with northbound Bayshore Boulevard. A northbound US 101 off-ramp to northbound Bayshore Boulevard is provided north of the project area. U-turns back toward the project site are prohibited well into the city of Brisbane. Interstate 280 (1-280) provides secondary regional freeway access to the project area. To the north, the eight-lane freeway provides access to Daly City, San Francisco and points beyond (Bay Bridge, Golden Gate Bridge, etc.); to the south, 1-280 provides access to the cities of San Bruno, Millbrae, Hillsborough, San Mateo, Redwood City and points beyond to San Jose. Local 1-280 interchanges serving the project area are located at Hickey Boulevard, Westborough Boulevard, and Avalon Drive. (2) Local Roadwav Network r Hillside Boulevard (Hillside Boulevard Extension) is a four-lane roadway in the project area along the base of San Bruno Mountain, extending north to Mission Street (Le., to State Route 82, the northbound extension of EI Camino Real in Daly City) and southeast to the downtown r area of South San Francisco. The designation "Hillside Boulevard Extension" pertains to the r newly constructed segment of roadway between Lincoln Street and Sister Cities Boulevard. Traffic flows are predominantly north/westbound in the evening. r The Hillside Boulevard Extension extends along the southern project boundary at the western r end of the project site. This four-lane arterial facility with a raised median adjacent to the r project site intersects the recently completed Sister Cities Boulevard about one-third of the distance along the southern site boundary and then turns to the southeast and continues as a r two-lane roadway (designated Hillside Boulevard) towards downtown South San Francisco through the residential neighborhood just south of the project site. It ends at an intersection with Linden Avenue, which connects directly to Airport Boulevard. Hillside Boulevard r Extension has signalized intersections with Sister Cities Boulevard and Jefferson StreeVSouth r San Francisco Drive (the Phase I project access), while Hillside Boulevard has signalized r intersections with Stonegate Drive and Linden Avenue. All-way stop sign control is provided at Lincoln Street. All other roadways (such as Chestnut Avenue and Evergreen Drive) are r stop sign controlled on their approaches to Hillside Boulevard or Hillside Boulevard Extension. WP511548\FSEIR\IV-C-REV.548 ... -Ii o. -.:: .~ co .. ~ ( PAIS Olpll\lH ---------------, /'. , ,-/ .,., L~., '\~ I : :::;: +-1t'I~ .J!L. r:;; ~ir+ CO .. N = ~ ... ~ ! .. " ZO PAIS O'O"".S Q " .. :: :: .. . III ------------- . L,..o '''\ ....,..f"t 4-: \ .JlL.r~ \ ;",=: 1! ~ ') i -. ""\ ...v ..1>.".0 ~'" .. & ~:~ - Ii .. . - ~ ID " ",0 t--. tJ) \C l!:: rT' Q"\ ~ ..... Q"\ ._~ ~ rJ...;J :::J .-J ;:J oe- >~ u::> -cO t::r:= <~ ~< ~~ .~ ~~ ~~ f-4 tJ) ..... >< ~ g. e (!) c o ~ ; ~ ni ~ ~ u w '" t) ~~ .. '0 .. ~ :! :. o ~ 11\ L =0 (.; ;~ ;:-~= \ :~.::: ~ j ~ ! . . CO ~~ ;: ... .. ii - :: o ~ .. . in L~ 1l. ~ jr+ ... . iii .. ~ :: - co .J!L.. r~ oJ ~ i r+ , ~:/ "o!,.) T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 94 Evergreen Drive is a two-lane residential roadway that extends between Mission Road on the west and Hillside Boulevard on the east. The route runs along the southern border of EI Camino High School just east of Mission Road. Chestnut Avenue extends easterly from EI Camino Real to Hillside Boulevard. The route has four lanes near EI Camino Real and Hillside Boulevard, but narrows to two lanes in places where roadway widening has not yet occurred (Le., east of Commercial Drive). Traffic flows are predominantly westbound in the evening. Sister Cities Boulevard is a four-lane divided arterial roadway running along the southern r project boundary. It extends from its signalized intersection with Hillside Boulevard Extension on the west to its signalized intersection with Oyster Point Boulevard/Airport Boulevard- Bayshore Boulevard on the east. There is only one intersection along Sister Cities Boulevard--Le., with South San Francisco Drive about halfway between Oyster Point Boulevard and Hillside Boulevard. This intersection is now signalized and will provide access into the Phase II area of the project. (South San Francisco Drive has been constructed as a paved construction vehicle roadway only between this intersection and the Phase I portion of the project--indicated by a dashed line on figures in this SEIR section--and to full city standards in the Phase I portion of the project.) Bayshore Boulevard is primarily a four-lane arterial roadway extending northerly from South San Francisco into the cities of Brisbane and San Francisco on the west of US 101. It continues southerly through South San Francisco as Airport Boulevard south of its intersection with Sister Cities Boulevard-Oyster Point Boulevard. Adjacent to the eastern boundary of the project, Bayshore Boulevard has two travel lanes in each direction, narrowing to single travel lanes near its intersection with the US 101 southbound off-ramp. Bayshore Boulevard is within the city limits of Brisbane and is thus within that city's jurisdiction. This includes the roadway right-of-way extending to the south and connecting with the city of South San Francisco, which is an incorporated "peninsula" of Brisbane, surrounded on the west, south and east by lands within the city of South San Francisco (see Figure 2). Airport Boulevard is a north/south arterial which parallels US 101. The arterial is four lanes wide except for a short, six-lane-wide section between Grand Avenue and the undercrossing at the Southern Pacific Railroad tracks. Because of its close proximity to US 101, freeway connections are provided to Airport Boulevard at several locations. Oyster Point Boulevard is a major arterial roadway extending easterly from Bayshore Boulevard-Airport Boulevard across US 101 and the CalTrain rail line into the Oyster Point Business Park. It has been recently widened and realigned in the vicinity of the freeway as part of the Oyster Point interchange reconstruction. The freeway overpass has eight travel lanes and a narrow raised median. Dubuque Avenue is a frontage road running along the east side of US 101 from Oyster Point Boulevard southerly to East Grand Avenue. It has two travel lanes along its entire length WP511548IFSEIRI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 95 except from Oyster Point Boulevard to its intersection with the freeway northbound off-ramp and southbound on-ramp, where up to eight lanes and a narrow raised median are provided. It has signalized intersections with East Grand Avenue, the freeway ramps and Oyster Point Boulevard. b. Exlstlna Traffic Conditions (1) Existina Intersection Operation (a) Study Intersections. Ten specific local road system locations have been identified by the city of South San Francisco staff as those most likely to be affected by the project. Seven are signalized intersections and three are stop sign-controlled intersections. These intersections r were evaluated for Base Case PM peak hour conditions. In addition, at California Department of Transportation (Caltrans) request, all intersections within or in close proximity to the Oyster r Point interchange were also evaluated for Base Case AM peak hour conditions. The locations of these intersections are shown on Figure 6; they include: Sianalized: . Hillside Boulevard/Jefferson Street-South San Francisco Drive (project Phase I access); . Hillside Boulevard/Sister Cities Boulevard; . Sister Cities Boulevard/South San Francisco Drive (primary project Phase II access); . Sister Cities Boulevard-Oyster Point Boulevard/Bayshore Boulevard-Airport Boulevard (AM and PM); . Oyster Point Boulevard/Dubuque Avenue-US 101 northbound on-ramp (AM and PM); . Dubuque Avenue/US 101 northbound off-ramp/US 101 southbound on-ramp (AM and PM); and . Bayshore Boulevard/project commercial access (Phase 1I1)/Realigned US 101 southbound on- and off-ramps (for 2010 conditions only) (AM and PM). AII-way-stop-sia n-controlled: . US 101 southbound off-ramp/northbound Bayshore Boulevard (AM and PM). Side-street -stop-sian-controlled: . Hillside Boulevard/Evergreen Drive; and . Hillside Boulevard/Chestnut Avenue. (b) Level of Service Scale. In order to understand the status of a local roadway network, a grading system called Level of Service (LOS) is commonly used by traffic engineers and planners. The LOS grading system typically used involves a rating scale which ranges from WP51 1548\FSEIRI/V-C-RE V. 548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 96 LOS A, indicating uncongested flow and minimum delay to drivers, down to LOS F, indicating significant congestion and delay on most or all intersection approaches. Tables B-1 and B-2 in Appendix B list the definitions of the LOS scales used in this analysis for local signalized intersections (based on volume-to-capacity ratios) and for local unsignalized intersections (based on delay in seconds). (c) Level of Service Methodoloav. Signalized intersections are evaluated in this study using the Transportation Research Board (TRB) Circular 212 planning methodology, adjusted as described in Appendix B for more accurate application to this project. The Circular 212 methodology is a standard level of service calculation method' and is appropriate for a planning analysis where future levels of service are to be projected. Unsignalized intersection operation was determined using the methodology outlined in the 1994 Highway Capacity Manual, as described in Appendix B. Following the procedures used in the East of 101 Area Plan DEIA (1994) traffic analysis prepared by Barton-Aschman, Inc., and the Oyster Point Interchanae Reconstruction and Grade Separation DEIR (1990) traffic analysis prepared by Fehr & Peers Associates, Inc., lane capacity adjustments were incorporated into the analysis of intersections that would otherwise operate at LOS C or worse. (d) Level of Service Standards. Level of Service D is considered by the city of South San Francisco to be the poorest acceptable operation for signalized and all-way stop intersections; LOS E is considered to be the poorest acceptable operation for unsignalized intersection turn movements. r (e) Intersection Turnina Movements. Figure 7 presents existing2 (June, 1996) AM and PM r peak hour turn movement volumes at major project area intersections. Ongoing construction r at the Grand Avenue freeway interchange (just south of the Oyster Point interchange) and the r construction period closure of the northbound freeway on-ramp from Grand Avenue during the r morning commute (and occasionally extending to the evening commute period) has resulted in r a temporary diversion of additional traffic through the Oyster Point interchange. The June, r 1996 counts at the Oyster Point interchange in Figure 7 reflect a closed Grand Avenue on- r ramp during the AM commute and an open ramp during the evening commute period. The r counts indicated that the peak afternoon traffic hour along Bayshore Boulevard was from 4:30 r to 5:30 PM, whereas the peak traffic hour along Hillside Boulevard was from 4:45 to 5:45 PM. (f) Existina Sianalization Needs. Traffic signal "warrants" are conventional standards used to determine whether a traffic signal is needed. A traffic signal should not be installed if no 'It is one of the methods specifically identified in the state's Congestion Management Program (CMP) legislation and is, therefore, accepted by the regional planning agency, the Metropolitan Transportation Commission. 2As explained in Appendix B, "existing" traffic volumes used as a basis for the year 2000 and 2010 base case traffic projections are 1996 volumes taken from the recent traffic counts in the project r vicinity. WP51 \548\FSEIRI/V-C-REV.548 T errabay Project City of South San Francisco August 29. 1996 Revised Draft SEIR IV.C. Transportation Page 97 warrants are met, since installation of traffic signals may increase delays for the majority of through traffic and increase some types of traffic accidents. If one or more warrants are met, a signal may be appropriate. A signal warrant analysis has been performed for the three unsignalized study intersections r for the 1996 PM peak hour, using Caltrans Warrant 11 criteria (see Appendix B). Currently, r volumes at the Hillside Boulevard/Chestnut Avenue and U.S. 101 Southbound Off- r Ramp/Northbound Bayshore Boulevard intersections exceed peak hour signal warrant criteria r levels. (2) Existina Freeway Operation r Table 7 shows that 1994 PM peak hour peak direction (southbound) operation along US 101 in the project vicinity is LOS E at all locations. Level of Service E operation is the minimum acceptable condition for peak hour operation of US 101 in South San Francisco as set by the r San Mateo County Congestion Management Plan.1 Criteria used to relate freeway level of service and volume to capacity ratio are presented in Appendix B. (3) Existina Transit Service (a) Local Bus Routes. Transit service is provided to the project area by the San Mateo County Transit District (SamTrans). Table 8 describes the SamTrans routes serving the project vicinity. Routes 7B and 24B travel along Bayshore Boulevard adjacent to the eastern project boundary while Route 26H travels along Hillside Boulevard west of Jefferson Street as well as along Jefferson Street. SamTrans service also provides/accepts inter-agency transfer passes to/from Santa Clara County Transit at shared bus stops, San Francisco Municipal Railway routes at selected points, and AC Transit routes at shared bus stops in Alameda, San Mateo and Santa Clara counties. (b) BART. BART currently does not directly serve the city of South San Francisco; rather, BART currently provides direct (BART station) Peninsula service as far south as Daly City, although a new station has been constructed in Colma and will be opening for passenger service within the next year. (c) Caltrain. An existing CalTrain station is located in the city along Dubuque Avenue just north of East Grand Avenue. Service is provided seven days per week, extending from San Francisco to Gilroy. r 11995 Congestion Manaaement Program; San Mateo County. Barton-Aschman Associates. Inc. WPS1 \S48IFSE/RI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 98 Table 7 EXISTING AND BASE CASE US 101 FREEWAY OPERATION--PM PEAK HOUR One-Way r Hourly ExistinQ (1994) Base Case (2000) Base Case (2010) SeQment Capacity" VolumeD VIC LOS Volume VIC LOS Volume VIC LOS r North of Sierra 8,800 8,400 .95 E 9,050 1.03 F 12,470 1.42 F Point r Sierra Point to 9,300e 8,000 .86 E 8,530 .92 E 11 ,310 1.22 F Oyster Point r Oyster Point to 9,300e 8,400 .90 E 9,370 1.01 F 14,190 1.53 F Grand Avenue r Grand Avenue 8,800 7,100 .89 E 9,150 1.04 F 13,660 1.55 F to South Airport r SOURCE: Crane Transportation Group, East of 101 Area Plan DEIR, and City of Brisbane 1993 General r Plan DEIR, Volume III. · Peak direction capacity based on 2,200 vehicles per hour through lane and 500 vehicles per hour per auxiliary lane. Transportation Research Board, 1994 Highway Capacity Manual, Table 3-1, using 60 mph freeway design speed. b From Caltrans traffic volumes 1994 for peak hour with assumed 55/45 directional split peak. Peak direction southbound. e On-ramp to auxiliary lane or off-ramp from auxiliary lane assigned increased capacity. WP51 \548\FSEIRI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 99 Table 8 PROJECT AREA LOCAL BUS ROUTE DESCRIPTIONS (SAMTRANS) Route Description ST 24B Local service along Bayshore Boulevard and Airport Boulevard between Daly City, Brisbane, South San Francisco and the San Francisco Airport. ST 7B Regional service along Bayshore Boulevard and Airport Boulevard between downtown San Francisco (Transbay Terminal) and Redwood City. ST 26H Local service to Tanforan Shopping Center along Mission Road, Hillside Boulevard, Jefferson Street, Linden Avenue, and Airport Boulevard. All three bus routes pass within 500 feet of the South San Francisco CalTrain Station. SOURCE: Crane Transportation Group, Samtrans. WP51 \548 \FSEIRI/V-C-RE V. 548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 100 c. Base Case Traffic CondItions This section describes anticipated local traffic conditions in the future without the project. Two future years are included in this analysis: 2000 and 2010. These year 2000 and 2010 traffic conditions are the "base case" to which project traffic will be added and serve as a benchmark against which project impacts will be evaluated. (1) Planned TranSpOrtation System Improvements (a) Hickey Boulevard Extension. The proposed Hickey Boulevard extension will extend from EI Camino Real eastward to Hillside Boulevard. The segment of the extension between EI Camino Real and Mission Road will be constructed by the BART District as part of the new Hickey Boulevard station improvements; San Mateo County will construct the segment r between Mission Road and Hillside Boulevard, potentially about one to two years after r completion of the EI Camino Real to Mission segment.' The extension design includes four r lanes with separate turn lanes at intersections. Signalized intersections will be provided at Hillside Boulevard, Mission Road and EI Camino Real. The city of South San Francisco portion of the Hickey Boulevard Extension was included in the city's 1992 program of capital improvements and is expected to be constructed before the year 2000. The county's portion will be constructed after the city's portion has been completed. r (b) Oyster Point Interchanee Reconstruction. As of this SEIR writing, this project is r complete, with the exception of the hook ramps and flyover. (c) Hillside Boulevard/Chestnut Avenue Intersection Siena!. A signal is planned for the Hillside Boulevard/Chestnut Avenue intersection. No specific date has been determined, as funding is still needed. No other roadway improvements are programmed and funded by the city of South San Francisco in the immediate project vicinity.2 Likewise, no improvements are programmed or funded by Caltrans for the US 101 freeway between the South San Francisco city limits and 1-380.3 (d) BART Extension Plans. Plans are being formulated by the Metropolitan Transportation Commission (MTC) and BART to extend BART from Colma to the San Francisco International Airport (SFO) via an alignment that would pass through the EI Camino Real corridor via the Southern Pacific Transportation Company railroad right-of-way. The extension plans also call for construction of a South San Francisco BART Station just south of the planned Hickey r 1Mr. Joe Lococo and Mr. Bob Cambron, Traffic Section, San Mateo County Public Works. 2Mr. Richard Harmon, City of South San Francisco Public Works Department. 3Mr. John Low, Caltrans District 4. WP51 \S48\FSEIRI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 101 Boulevard Extension. EI Camino Real would border the BART site to the west, Mission Road to the east, and a new street to the south. (2) Base Case Traffic Assumptions. AM and PM peak hour traffic volumes for project study intersections for year 2000 Base Case conditions are presented in Figures 8 and 9, respectively, while Figures 10 and 11 present AM and PM peak hour volumes, respectively, r for year 2010 Base Case conditions.' These traffic volumes are based on recently completed r traffic counts at the Oyster Point interchange and along Hillside Boulevard as well as future traffic projections contained in studies prepared for other projects in the area, adjusted to produce a coherent set of volumes for the project area circulation network (see Appendix B). Figure 12 presents intersection geometries assumed for both year 2000 and 2010 background conditions without the project. 2 r (3) Base Case Intersection Sianalization Needs. The following year 2000 and year 2010 r Base Case signalization warrants have been identified (without the project): r (a) Year 2000. Two intersections would have volume levels exceeding peak hour signal r warrant criteria levels: r . U.S. 101 Southbound Off-Ramp/Northbound Bayshore Boulevard - AM peak hour r . Hillside Boulevard/Chestnut Avenue - PM peak hour r (b) Year 2010. Two intersections would have volume levels exceeding peak hour signal r warrant criteria levels: r . U.S. 101 Southbound Off-Ramp/Northbound Bayshore Boulevard - AM and PM pe'ak r hours r . Hillside Boulevard/Chestnut Avenue - PM peak hour r (4) Base Case Intersection Level of Service. Table 9 presents year 2000 and 2010 Base Case (without project) AM and PM peak hour levels of service at study intersections. , For purposes of this analysis, two existing unsignalized intersections were assumed to be signalized by either the year 2000 or 2010, since volumes at each would exceed peak hour signal warrant criteria: · Hillside Boulevard/Chestnut Avenue (by 2000 - however, volumes already exceed warrant levels); and · US 101 southbound off-ramp/northbound Bayshore Boulevard (by 2000 for AM peak hour; by 2010 for PM peak hour). 2The assumed geometries are those currently in place along Hillside Boulevard, Sister Cities Boulevard, Bayshore Boulevard, Oyster Point Boulevard, and Dubuque Avenue. WPS11548IFSEIRI/V-C-REV.S48 Sister Cities Blvd L 760 110 190 134S +- 80 J~l.t65 60 J ~ t r+ 380 -+ 10 30 220 10 -. ~h SOURCE: Crane Transportation Group 1225 SB 101 OHramp ~" ( \ \ '" +- 135 t 130 ... 275 --.J 1205 -+ 275 -. ijr+ 120 810 30 ." > =:I .. .. <;) ..c: ., > .. =:I ~~, iii / 95 L 0 " \ I 310 0 - 0 \ ~ J~l.tO \ .::: < 865J ijr+ 30 0 95 ./ 0-+ 15 -. o SB 101 NB 101 ~ Onramp OHramp g .J:l =' o Figure 8 YEAR 2000 BASE CASE TRAFFIC VOLUMES WITHOUT PROJECT AM PEAK HOUR TERRABA Y PROJECT SEIR UTYOFSOUTHSAN FRANCISCO,CALlFORNIA Wagsta11 and Associates ... -& ::.= 11I- .~ :::, .... - o : ( P"II "'P'I\IH ~/~;'\ i ::::: +-: ..J~L.,r: 1lr) ... ~ ! III c: %0 ~ III -----, .. '-- ~ .,"'''' +-:;: ~~L.,r= " ~J ~ i I ,! ~ - 5~:: A 5+ ,/ \ i,&V anDnqllQ ~... ~:~ %0 ... - & co . - ~ III c: ...0 0\ CJ) ~ ~~;:J 5'0~ .-~O ~~ :t ~~ 0< >~ U~ s:~ ~~ o <5 c: o ~ I '" ~ ~ '" t5 w ~ u <g ~ P"II uoqdWI ('----- I I I :1 al ~ : . c: . '" ... ;; \. o c: .. : = > III G '0 ... ~ .. o ~"II 1.04..V .. .. o 0 ~ =:0 ( ~ r ~ ?~~ I : !J~il) \ ~ .. " :;:;........ 00 N \~\ ... > ;; . ;; u ~ ; ;;; L= \ ~ \ <JV IS 110....11..1 - 0 ... > ;; .. ~ :: L.. ..J~L.,r~ oj ~ i I \ o..~ "::: / ~I I,. v,) US 101 Sister Cities Blvd '- ~ Oyster Point Blvd ~'\ / +-- 185 \ , ! ! .rm I i, 530 - ." > ii i ii, 105 2330 / 30 / 5.5 10 2190 +-- 120 J ~ L. .r 90 90 -' .. .. Q .c .. > .. = " 2QS t - .. Q " .. < US 101 ~,. / 520 0 +-- 0 ( JJL..ro I \ \ / , ." > ii ... 2'00 ---.i 0- iil '0 0 65 SB 101 onramp\ .. > NB 101 < OHramp ~ <:r' " .Q " Q SOURCE: Crane Transportation Group Figure 10 YEAR 2010 BASE CASE TRAFFIC VOLUMES WITHOUT PROJECT AM PEAK HOUR ~rth TERRABA Y PROJECT SEIR CITY OF ~OUrH SAN FI{,.\NCISCO, CALIFORNIA Wagstaff and Associates ... -& ~.= ..- '~ :: -......: .. - ; . PAIB '!P'lI!H ------------ / --------------- " ~ 0 L:::."\ a 0 N .... \ = :::::: "'-0::: \ .J~L. r::: \ ~ill o .. ) - 0 = - - .. I ... c; & - . .. c zo / L \ /........1In ....- "': \ I I~L. r= I, Ie-', '\ ..J ~ i i J ~ ~ .. "UY :D;qllO ~.: ~z: - e 0:> . - ~ .. C ",0 c Ci ... ~ u . ... o PAIB OJO'l''''B ~"IB 'JO.u.y 0 ~~ ! ~ r ~ ;:-;l: \ i .... ___ .. ~ : " ~~ I IIi \~;-- .. : ; -0 ::::: / ...-, - . . ." ~ .. - ~ U .J~ ~ ; ~! ) in Y oj L= c . 0 '" :: "'u - c " . o ~ cnfL ~ = ." ~ .. .. ~ L.. - 0 .J~L. r~ o o.=: ~! ~ ) 0-' .. Q c :: = ~I ::: en ~ ~~~ .~~O Po. ~ :I: ~~ 0< >~ U~ ~~ ~~ <. ~. ~b ~~ en ~ <0 U~ ~~ en~ <~ ~O 0== l""'4~ O~ ~~ < ~ )-4 Q. ~ o ~ <:: o I '" ~ ~ '" U UJ -'" u <'g ~ T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 106 (a) Year 2000. All analyzed study intersections would operate acceptably during the AM peak hour, with one exception: the US 101 southbound off-ramp/northbound Bayshore Boulevard intersection. Even if signalized, this intersection would operate at LOS E during the year 2000 AM peak hour. All study intersections would operate at acceptable levels of service during the 2000 PM peak r hour with one exception: Hillside Boulevard/Chestnut Avenue if it remains unsignalized. The stop sign-controlled left turn movement from Chestnut Avenue to Hillside Boulevard would operate at LOS F. Significant extended delay would be experienced by drivers attempting this r movement. PM peak hour volumes at this location would be exceeding peak hour signal warrant criteria levels. (b) Year 2010. Three intersections would experience unacceptable operation during the AM peak hour: . Sister Cities Boulevard/Oyster Point Boulevard/Bayshore Boulevard/Airport Boulevard (LOS F signalized operation); . Oyster Point Boulevard/Dubuque Avenue/US 101 northbound on-ramp (LOS F signalized operation); and r . US 101 southbound off-ramp/northbound Bayshore Boulevard (LOS F - if signalized but r without additional intersection approach lanes). r Five intersections would experience unacceptable operation during the PM peak hour: . Sister Cities Boulevard/Oyster Point Boulevard/Bayshore Boulevard/Airport Boulevard (LOS E signalized operation); r . Oyster Point Boulevard/Dubuque Avenue/U.S. 101 Northbound On-Ramp (LOS F r signalized operation); . Dubuque Avenue/US 101 northbound off-ramp--southbound on-ramp (LOS E signalized operation); . Hillside Boulevard/Chestnut Avenue (if this intersection remains unsignalized, the stop sign-controlled left turn movement from Chestnut Avenue to Hillside Boulevard would be operating at LOS F); and . US 101 southbound off-ramp/northbound Bayshore Boulevard (This all-way stop intersection would be operating at LOS F. If signalized, but without additional intersection approach lanes, operation would be an unacceptable LOS E). r (5) Base Case Freeway Operation. Table 7 also presents year 2000 and 2010 Base Case PM peak hour operation for US 101 in the project vicinity. WP51 \548\FSE/RI/V-C-REV.548 /t" (.! llll_ 1= '\\ ~h /' ~ all.V anb:qna I . )Z~/~/+I..1- oS \\ iiirs~ ~ / r \~ ~~ '- / :. . ! ~ Co. ~ ~ ~ ~i I ; ~ ~ o -. :::a -. ~ (--11 LAL. r ) \ ~ 1 it ~j ~/ ~ c Ololl Vi Q.. ... o ~ v; Vi II II --. "\ PAIS a~ol{'US ~71 Jl1 \ ~ .J -, ii) ~ ~ L lll~ I ~ tt ..a~~v pa!O~d .... .. ;; .. ~ Jlll + i -i. -, ir ~ ~B..:I ~ ~Zu .~<~ f,L.~O Z~ O~ I-I~ ~~ ~o en:c ~~I ~~ ~~ Zen I-IU ~~ en ~, <~I U~ ~~ enO <~ ~'-' o ~ o N o Z < o o o N ~ < ~ ;>c Q. ~ '" C e " <!l .. c:: :: 0 ~ 'i 1: .. ~ .. III l'll ~ ~ l'll cJ -C UJ (! <..l c:: :;) 0 en T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 108 Table 9 BASE CASE INTERSECTION LEVEL OF SERVICE--(AM) AND PM PEAK HOUR Intersection Year 2000 Base Case Year 2010 Base Case (without flyover) r Signalized r Hillside Blvd/Jefferson SV South San Francisco Drive (Phase I Access) r Hillside Blvd/Sister Cities Blvd A - .36* A - .42 A - .43* A - .48 Sister Cities Blvd/South San Francisco Drive/(Phase II Access) r Sister Cities Blvd/Oyster r Point Blvd/Bayshore Blvd/ Airport Blvd r Oyster Point Blvd/Dubuque rAve/US 101 NB on-ramp r Dubuque Ave/US 101 NB r off-ramp/US 101 SB on-ramp Bayshore Blvd/US 101 SB ramps/Project Commercial Access (Phase III) N/A N/A (D - .72)* (F - 1.27) C - .59* E - .87 (B - .52)* (F -1.58) C - .67* F - 1 .22 (A - .35)* (0 - .82) A - .43* E - .92 N/A N/A Unsignalized r Hillside Blvd/Evergreen Dr r Hillside Blvd/Chestnut Ave r r US 101 SB off-ramp/NB r Bayshore Blvd (All-Way Stop) r r o - 20.9** C - 13.1 F*** F*** A - .44 (F)*"* (F)**" (E - .897)* (F - 1.60)* C - 14.4.... F.... A/B - .50* E - .96* SOURCE: Crane Transportation Group. * Signalized level of service - volume/capacity ratio. .. Unsignalized level of service/average vehicle delay (in seconds) - eastbound left turn from Evergreen Drive. r *** Unsignalized level of service/average vehicle delay (in seconds) - eastbound left turn from Chestnut r Avenue. r **.. All-way stop Level of Service - average vehicle delay in seconds (overall intersection). WP51 \548\FSEIRI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 109 (a) Year 2000. All segments of US 101 would have peak direction (southbound) traffic r operating at unacceptable LOS F conditions during the PM peak hour with one exception: the r segment from Sierra Point to Oyster Point would be in the acceptable LOS E range. (b) Year 2010. All freeway segments near the project would be experiencing unacceptable LOS F PM peak hour operation for peak direction (southbound) traffic flow. Demand would be from 20 to more than 50 percent greater than capacity, depending upon the freeway segment. r (6) Base Case Freewav Ramp Operation. Table 10 presents year 2000 and 2010 Base Case AM and PM peak hour operation for US 101 ramps included in this study. (a) Year 2000. Year 2000 AM and PM peak hour traffic volumes at all three US 101 freeway ramps at the Oyster Point interchange (northbound on and off, as well as southbound on) and the southbound off-ramp to Bayshore Boulevard would be well under capacity. Although the southbound off-ramp would have volumes well within the acceptable range, the r off-ramp intersection with northbound Bayshore Boulevard would be operating at an unacceptable AM peak hour LOS E with existing geometrics and with signalization. It would be expected that off-ramp traffic would back up to the southbound freeway mainline unless additional lanes were provided on the intersection approach or unless off-ramp detectors would control signal operation and allow off-ramp traffic to clear whenever backups approached the freeway mainline. (b) Year 2010. During the 2010 AM peak hour, traffic volumes would exceed capacity at the r southbound off-ramp to Bayshore Boulevard and the northbound off-ramp to Dubuque r Avenue. As a result, southbound off-ramp traffic could be expected to back up well into the freeway main line. Northbound off-ramp traffic would back up well into the auxiliary lane extending from the Grand Avenue on-ramp. r Year 2010 PM peak hour traffic volumes at two of the three freeway ramps at the Oyster Point r interchange (northbound off and southbound on), as well as the southbound off-ramp to r Bayshore Boulevard, would be under capacity. r The two-lane southbound on-ramp would be operating at 90 percent of capacity with a r demand of almost 2,900 PM peak hour vehicles. The northbound on-ramp at the Oyster Point r interchange would, however, be operating at capacity. 2. 1982 EIR IMPACT AND MITIGATION FINDINGS The 1982 EIR traffic analysis was based on the conservative ("worst case") assumption that construction of all project phases would be completed by 1990. Table 11 presents 1982 and estimated 1990 traffic conditions without the project, Hillside Boulevard Extension (Sister Cities Boulevard) or the Oyster Point interchange project, and estimated 1990 and 2000 traffic WP511548IFSElRI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 110 Table 10 BASE CASE US 101 FREEWAY RAMP OPERATION--(AM) AND PM PEAK HOUR WITHOUT THE PROJECT Base Case (2000) Base Case (2010) US 101 Ramp Capacity* Volume Operation Volume Operation r SB off-ramp to Bayshore 1,800 (1 ,225) (under (2,455) (over Blvd capacity) capacity) r 520 under 1,160 under capacity capacity r NB on-ramp from Oyster 2,000" (485) (under (640) (under Point Blvd capacity) capacity) r 1,340 under 1,995 at capacity capacity r NB off-ramp to Dubuque 2,000" (880) (under (2,460) (over Ave capacity) capacity) r 590 under 995 under capacity capacity r SB on-ramp from Dubuque 3,200 (340) (under (560) (under Ave capacity) capacity) r 1,325 under 2,880 under capacity capacity SOURCE: Crane Transportation Group, TRB Special Report 209, 1994 Highway Capacity Manual. r * Passenger cars per hour. On-ramp to auxiliary lane or off-ramp from auxiliary lane assigned r increased capacity. r .. Although the southbound off-ramp would have volumes well within the acceptable range, the off-ramp r intersection with northbound Bayshore Boulevard would be operating at an unacceptable PM peak hour r LOS E with existing geometrics and with signalization. r *** On-ramp to auxiliary lane. It would be expected that off-ramp traffic would back up to the r southbound freeway mainline unless additional lanes were provided on the intersection approach or r unless off-ramp detectors would control signal operation and allow off-ramp traffic to clear whenever r backups approached the freeway mainline. WP511548IFSE/RI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 111 Table 11 PEAK HOUR INTERSECTION LEVELS OF SERVICE COMPUTATIONS--1982 EIR With Project Without Proiect With Proiect and Mitiaations Existing (1982) 1990 1990 2000 1990 2000 Hillside Boulevard/Chestnut Avenue A A A C/O A B/C Hillside Boulevard/Kearny Street A AlB1 AlB' C/D1 A1 A1 Hillside Boulevard/Irving Street A AlB1 C1 E/F1 A1 B1 Hillside Boulevard/Jefferson Avenue A C A B Hillside Boulevard/Randolph Avenue A B B/C E/F AlB C Linden Avenue/Airport Boulevard C F F F E5 E/F5 Oyster Point Boulevard/Airport Boulevard B F2 F2 F2 -- 6 -- 6 Oyster Point Boulevard/Dubuque Avenue B F2 E4 F4 -- 6 -- 6 US 101 Southbound Off-ramp/Bayshore Boulevard B F E4 E4 AlB B Sister Cities Boulevard/Airport Boulevard -- -- 3 F -- 6 -- 6 SOURCE: EIP Corporation 1982. Draft Environmental Impact Report for the Terrabav Development Proiect. San Mateo County, California. 1 Assumes removal of stop signs on Hillside Boulevard from existing 3-way stops. 2 Assumes existing interchange still in place. 3 Depends on intersection configuration and Oyster Point grade separation. 4 Assumes off-ramp widened to two lanes. 5 Can be improved by two service levels if Oyster Point interchange includes southbound on-ramp. 6 Depends on design of Oyster Point interchange and Sister Cities Boulevard. WP51 1548\FSE/RI/V-C-RE V. 548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 112 conditions with the project at the key project vicinity intersections. Associated traffic impact findings and mitigation measures identified in the 1982 EIR are summarized in Table 12. 3. SUPPLEMENTAL IMPACT FINDINGS r The Terrabay project will be adding incrementallv to cumulative (Base Case) traffic impacts in the project vicinity. Traffic analyses performed for other projects in the vicinity indicate increasing traffic volumes and worsening operations. As a result, several of the study r intersections would already be operating poorly under Base Case conditions without the r project. In fact, with only three exceptions,1 all Intersections, freeway ramps and freeway r segments for which significant adverse project Impacts have been Identified would r already be experiencing unacceptable Base Case operation (I.e., significant Impacts) r without the project. r This section presents the potential transportation impacts of the project for the years 2000 and r 2010. The year 2000 analysis assumes only Phase I of the project will be built, occupied and r adding traffic to the local road network by that time. For the year 2010, two possible impact r scenarios are evaluated: completion and occupancy of Phase I only, and completion and r occupancy of Phases I, II, and III. This SEIR analysis has been designed to conform with CEQA, city of South San Francisco, and San Mateo County Congestion Management Agency (CMA) traffic impact analysis requirements. Impacts identified in this SEIR are generally similar to those identified in the 1982 EIR. The project trip generation estimate prepared for this SEIR is substantially similar to that estimated in the 1982 EIR (see Table 12). Intersection operation impacts were also identified at the same general locations: the Sister Cities Boulevard/Oyster Point Boulevard/Airport Boulevard/Bayshore Boulevard intersection, the US 101 southbound off-ramp/northbound Bayshore Boulevard intersection, and the US 101 ramps at Dubuque Avenue (although these ramps have been reconstructed as part of the Oyster Point interchange project). The 1982 EIR also identified intersection operation impacts at the intersections of Linden Avenue with Hillside Boulevard and Airport Boulevard. These intersections were not included in this analysis, primarily because construction of Sister Cities Boulevard has diverted a substantial amount of traffic from this route. r 1The three exceptions include year 2010 Phase I, II and III AM and PM peak hour impacts at the r Bayshore Boulevard/US 101 southbound on- and off-ramp/project commercial access drive (a proposed r new intersection to be constructed with the project) and the PM peak hour impact at the Serramonte r Boulevard/Hillside Boulevard intersection (for which Base Case conditions were not available and the r project impact is based on an increase in traffic volumes rather than a change in operating conditions). WP51 \S48\FSE/R\/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 113 Table 12 1982 EIR TRANSPORTATION IMPACT AND MITIGATION FINDINGS Impact Summary The proposed project would be expected to generate approximately 16,570 daily trips on an average weekday following full occupancy (85 percent for the hotel): 6,100 (37 percent) by the residential areas and 10,470 (63 percent) by the commercial area. Approximately 1,710 pm peak hour trips would be generated. Approximately 15 percent ot these trips would occur between different on-site activities and would be entirely onsite or would only affect roadways fronting the site. The project would result in increased peak period traffic congestion at the following key intersections in the project vicinity: . Hillside Boulevard/Linden Avenue . Airport Boulevard/Linden Avenue . Airport Boulevard/Oyster Point Boulevard · Oyster Point interchange ramps (Dubuque) · US 101 southbound off-ramp/Bayshore Boulevard The project would increase peak hour traffic volumes on the US 101 main line (on which traffic volumes would already be at capacity) by approximately tour percent in 1990 and by a greater amount in 2000 contributing to a significant cumulative impact. The project would increase traffic volumes on Hillside Boulevard between Chestnut Avenue and Randolph Avenue to levels requiring traffic controls. The project would increase traffic volumes along Hillside Boulevard between Lincoln Avenue and Randolph Avenue by 100 percent in 1990 and 180 percent in 2000, which would significantly impact residents along that segment of Hillside Boulevard. WP51 1548\FSEIRI/V-C-RE V. 548 Mitiaation Summary Construction of the Oyster Point Interchange, before completion of the proposed project. Construction of the Sierra Point interchange and Bayshore Boulevard connectors to intercept traffic bound for the Linden Avenue US 101 southbound on-ramp via Bayshore Boulevard-Airport Boulevard. Redesign of the US 101 southbound "scissors" off-ramp, before hotel occupancy, including relocation of Bayshore Boulevard slightly west into the project property to accommodate a redesigned hook off-ramp and new hook on- ramp, and signalization of the new project commercial access/US 101 ramps intersection. Project sponsor fair share contribution to traffic signals at the following intersections before 1990: · Hillside Boulevard/Chestnut Street · Hillside Boulevard/Hillside Extension · Hillside Boulevard/Airport Boulevard · Oyster Point interchange (at one or more locations depending on final design) · US 101 southbound "scissors" off-ramp · Hillside Boulevard/Jefferson Street · Terrabay commercial access Removal ot the existing all-way stop signs on Hillside Boulevard/Kearny Street and Hillside Boulevard/Irving Street intersections in conjunction with installation of traffic signals along Hillside Boulevard. Create a frontage road or traffic free zone with landscaped buffer separating local access movements from higher speed traffic along Hillside Boulevard. T errabay Project City of South San Francisco August 29, 1996 The project would generate an additional approximately 400 daily transit trips and contribute to a cumulative increase in demand for transit of at least 2,000 daily trips. Revised Draft SEIR IV.C. Transportation Page 114 Implementation of the following transportation system management (TSM) measures, primarily in conjunction with development of the office condominium/health club/restaurant complex: · limousine service from the airport to the hotelttech trade center; · bus pullouts and shelters along Bayshore Boulevard and Hillside Boulevard; · Preferential carpool parking in the commercial area; · Encouragement of staggered work hours; · Encouragement of vanpooling/carpooling through the homeowners association; and · Encouragement of expanded transit service. SOURCE: EIP Corporation, 1982. Draft Environmental Impact Report for the Terrabav Development project. San Mateo County, California. WP51 \548\FSElRIIV-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 115 Freeway link impacts were also similar to those identified in the 1982 EIR. However, freeway ramp impact findings in this SEIR are different than the 1982 EIR due to the reconstruction of the Oyster Point Boulevard interchange. a. SIanlflcance Criteria The following criteria have been used to evaluate the significance of identified transportation impacts: . If a signalized or all-way stop intersection with Base Case (without project) volumes is operating at LOS A, B, C, or D and deteriorates to LOS E operation (or worse) with the addition of project traffic, the impact is considered to be significant and will require mitigation. If a Base Case stop sign-controlled turn movement deteriorates to LOS F operation with the addition of project traffic, the impact is considered to be significant. . If the Base Case LOS at a signalized or all-way stop intersection is already at LOS E or r F, or the Base Case LOS of a stop sign-controlled turn movement is already LOS F, a r two percent or more increase in total traffic entering the intersection due to the project is r considered to be significant.' . If traffic volume levels at an unsignalized intersection increase above Caltrans Peak Hour Warrant 11 criteria levels with the addition of project traffic, the impact is considered to be significant. . If Base Case traffic volume levels at an unsignalized intersection already exceed signal r warrant criteria levels, an increase in traffic of two percent or more due to the project is r considered to be significant.2 . If, in the opinion of the SEIR traffic engineer, certain project-related traffic changes will significantly increase safety concerns, the impact is considered to be significant. r 'Twenty-five Bay Area cities, counties and congestion management agencies were surveyed for the r traffic impact significance criteria they use in preparing planning and CEQA environmental documents r where a facility is projected to already experience unacceptable operation without the addition of project r traffic. None of the jurisdictions surveyed use V/C ratio impact criteria for freeway ramp, freeway main r line segment, or unsignalized intersection operation, or for intersection signal warrant analysis. A few r of the jurisdictions surveyed have adopted criteria for signalized intersections: both the Town of Corte r Madera and the City of Mountain View use a change in VIC ratio of .01; other jurisdictions vary the r threshold depending on the project and its location. Surveyed jurisdictions that have segments of the r congestion management program (CMP) freeway network within their boundaries typically specify a r minimum acceptable freeway ramp intersection operation the same as that of the associated freeway r link. Although the 1995 San Mateo County Congestion Management Program specifies a minimum r acceptable operation for US 101 through South San Francisco of LOS E, all ramp intersections at the r Oyster Point interchange have been evaluated in this EIR using the city's more stringent criterion of r LOS D. r 2lbid. WP51 \548\FSEIRI/V.C.REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 116 · If freeway link operation is currently at LOS A, B, C, D, or E, and changes to LOS F with the addition of project traffic, the impact is considered significant and will require mitigation. · If freeway link operation with Base Case volumes is already LOS F, an increase in peak r direction traffic of two percent or more due to the project is considered significant.1 r . If acceptable freeway on- or off-ramp operation changes to unacceptable levels (based r on the capacity of the ramp, as presented in Table 10) with the addition of project traffic, r or if project traffic increases Base Case volumes by two percent or more when operation r is already unacceptable, the impact is considered significant.2 b. Profect Trip Generation Tables 13 and 14 present updated trip generation projections for each of the three project phases based on current Institute of Transportation Engineers (ITE) trip generation rates. Trip rates from the 1991 and 1995 ITE Trip Generation manual, 5th Edition, were used to update trip rates used in the 1982 EIR. Phase I (293 single family residential and townhouse units) would be expected to generate about 2,700 daily two-way trips with 70 inbound and 160 outbound trips during the AM peak hour, and 185 inbound and 110 outbound trips during the PM peak hour. About 80 percent of the total AM and PM peak hour trip generation would be associated with residential uses. All Phase I traffic would access Hillside Boulevard via South San Francisco Drive at the Jefferson Street intersection. A small proportion of generated trips would be expected to be internal within the site (trips back and forth to the recreation center as well as drop off and pick up trips at the day care center by project residents). Phase 1/ (428 townhouse and condominium units) would be expected to generate about 2,600 daily two-way trips with 30 inbound and 160 outbound trips during the AM peak hour, and 155 inbound and 85 outbound trips during the PM peak hour. Phase II traffic would access Hillside Boulevard via South San Francisco Drive at the Jefferson Street intersection, and Sister Cities Boulevard via South San Francisco Drive. Phase III development of office, restaurant, health club, hotel and trade center commercial uses would be expected to generate about 10,600 daily two-way trips with 920 inbound and 180 outbound trips during the AM peak hour, and 385 inbound and 920 outbound trips during the PM peak hour. The commercial area trip generation projections assume full use of the hotel's proposed 600-seat seminar center and the tech trade center's 240,900-square-foot showroom. Commercial area trip generation would decrease by more than 30 percent with no r llbid. r 2lbid. WPS1 \548\FSEIRI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 117 Table 13 PROJECT DAILY AND PM PEAK HOUR TRIP GENERATION No. of Daily Two-Way PM Peak Hour Trips Units or Trips In Out Phase Use Size Rate Volume Rate Volume Rate Volume Residential-Single 125 units 9.55 1,200 .65 85 .36 45 Family Residential- 168 units 6.01 1,010 .37 65 .20 35 Townhouse Childcare Center 2,880 ft.2 79.3 230 6.40 20 7.22 20 Recreation Center .40 200 .024 ~ .016 -1Q Phase 1 Total 2,640 185 110 II Residential- 428 5.90 2,530 .36 155 .19 85 Townhouse/ Condo/T erraced Units Phase 2 Total 2,530 155 85 III Office 57,500 ft.2 930 ** 20 ** 105 Quality 150 seats 2.86 430 .16 25 .08 15 Restaurant Health Club 600 members .40 240 .024 15 0.16 10 Hotel 400 rooms.** 8.70 2,960 .41 140 .35 120 Seminar Center 600 seats 2.40 1,440 .11 65 .50 300 Restaurants 500 seats 2.86 1,430 .16 80 .08 40 Tech. Trade Center Office 27,800 ft.2 . 520 ** 15 .. 55 Showroom 240,900 ft.2 11.0 2,650 .10 ~ 1.15 275 Phase 3 Total 10,600 385 920 Total Project 15,nO 725 1,115 SOURCE: Trip Generation, 5th Edition, Institute of Transportation Engineers, 1991 and 1995 Update. . Ln(T) = .756 Ln(x) + 3.765 ** Ln(T) = .737 Ln(x) + 1.831 **. 85 percent occupancy assumed WP511548\FSEIR\IV-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 118 Table 14 PROJECT AM PEAK HOUR TRIP GENERATION No. of AM Peak Hour Trips Units or In Out Phase Use Size Rate Volume Rate Volume Residential-Single 125 units .19 25 .55 70 Family Residential- 168 units .07 15 .37 65 Townhouse Childcare Center 2,880 ft.2 8.20 25 7.00 20 Recreation Center 500 members 5 5 Phase I Total 70 160 II Residential- 428 units .07 30 .37 160 Townhouse/ CondolT erraced Units Phase II Total 30 160 III Office 57,500 ft.2 110 . 15 Quality 150 seats .028 5 .002 0 Restaurant Health Club 600 members .015 10 .005 5 Hotel 400 rooms" .40 140 .27 95 Seminar Center 600 seats .50 300 .05 30 Restaurants 500 seats .028 15 .002 5 Tech. Trade Center Office 27,800 ft.2 . 65 . 5 Showroom 240,900 ft.2 1.15 275 .10 25 Phase III Total 920 180 Total Project 1,020 SOO SOURCE: Trip Generation, 5th Edition, Institute of Transportation Engineers, 1991 and 1995 Update. Ln(T) = .777 Ln(x) + (89% in/11 % out) T = Trips, X = size in 1 ,000 sq. 1t. .. 85 percent occupancy assumed WP51 \548\FSEIRIIV-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 119 activity at the hotel seminar center and minimal activity at the trade center showroom. It would be expected that about five percent of the total commercial area AM peak hour trip generation and 10 percent of the total commercial area PM peak hour trip generation would remain internal to the site (back and forth trips between the hotel, restaurant, office, trade center and health club uses). Phase III traffic would access the west side of Bayshore Boulevard at three locations to the north of the Oyster Point interchange; two right-turn in and out driveways and one new signalized intersection. Figure 13 presents the lane striping assumed for analysis purposes at this new intersection along Bayshore Boulevard. Total project gross trip generation would be 15,770 daily two-way trips with 1,020 inbound and 500 outbound trips during the AM peak hour, and 725 inbound and 1,115 outbound trips during the PM peak hour. It should be noted that other than the internal trip capture described r above, no other specific reductions In trip generation due to Increased transit use, r carpooling, etc., were factored Into the project trip generation projections. c. Prolect Trip Distribution Table 15 presents the estimated PM peak hour in and outbound distribution of project residential and commercial traffic. AM distribution would be expected to be approximately the reverse of PM distribution. Distribution projections are based upon input from both the East of 101 Area Plan DEIR and EI Camino Corridor Redevelopment ProQram DEIR traffic analyses. Figures 14 and 15 present the AM and PM peak hour volume increments, respectively, for project Phase I while Figures 16 and 17 present AM and PM peak hour volume increments, respectively, for all project phases (Phases I, II and III), distributed to the local roadway network. Figures 18 and 19 present the sum of the 2010 Base Case .Q!!& the project incremental traffic volumes for AM and PM peak hour traffic conditions, respectively. d. ProJect Slanallzatlon Needs Impacts r Year 2000 - Phase I. Year 2000 Base Case volumes at the Hillside Boulevard/Chestnut r Avenue intersection (PM peak hour) and the US 101 Southbound Off-Ramp/Northbound r Bayshore Boulevard intersection (AM peak hour) would exceed peak hour signal warrant r criteria levels. Phase I traffic would further increase year 2000 Base Case volumes above r signal warrant criteria levels. This would be considered a significant impact at r Hillside/Chestnut as the project volume increase would be greater than two percent, but not a r significant impact at the Southbound Off-Ramp/Northbound Bayshore Boulevard intersection, r as the volume increase would be less than two percent. (Supplemental Impact T-1) r Year 2010 - Phase I. Phase I traffic would also aggravate the Year 2010 Base Case signal warrant criteria need for signals at the Hillside Boulevard/Chestnut Avenue and US 101 r southbound off-ramp/northbound Bayshore Boulevard intersections. The impact would be r considered significant at Hillside/Chestnut as the project volume increase would be greater r than two percent, but not significant at the Southbound Off-Ramp/Northbound Bayshore WP51 \548\FSEIRI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 120 Table 15 PROJECT TRIP DISTRIBUTION--PM PEAK HOUR Residential Inbound Outbound Commercial Inbound Outbound North (Daly City/San Francisco, North Bay, Bay Bridge via 101/ Bayshore Blvd.lI-280, EI Camino Real & Hillside Blvd. 35% 20% 35% 30% South (cities south of SSF via 101 /1-280/EI Camino Real) 40% 25% 40% 50% Local (Brisbane/South San Francisco) 25% 55% 25% 20% SOURCE: Crane Transportation Group; East of 101 Area Plan DEIR Traffic Analysis, Barton-Aschman Associates, Inc., 1994; ABAG, 1994; San Mateo County CMP. WP51 \548\FSEIRIIV-C-REV.548 -,,- -"- ~IS => IS .. - .. IZII" ~ '" c: ~::: 0 Ov ~" "- '" ", - ~ / ~'=> g ,,/ /Illl 1= '\ ~~ I~. - ~ ~ \ 1nirr: ~ \..~ ~ \ v ' . ' ~ ' 0 .2 "- IS"'I::I_ .. " ~ - - .. - c: Os 2~ III .. "'- ..... ,,- - ~ 00 ZZ g a,ol{u.g PAl .. ~ / := ~ /,1 +-J L L. r I 'V l"quaplpulI ~ E ", -Y l i r / / =-. . pa!o /,'c1 ~ · ~~~_/}lJ \ ! ~.~ (j -lit!" -'6 \ J ) III C ~8 -. / C ~1Il ~ tlD u", v; tG tG >-u g. ~ "'E III v; U; 0:; II CD II -*-e* c:: c: 0 .. ... "'- ...<:: _ c: = .. .:; .:: "IlUaplp.all \.. ua>>v I . pa!o,c1 "'1::1 .. iii \~ Q c: v :: ~ v > "'. \ '---+ . \",~. C"J CJ) ~ ';:uu .... ~ rT1 5b,..; ...... ._~~ ....~O ~c== ~~ O:c ~~ C-'~ ~~ Z < ~ Z o ~ ~ u ~ CJ) c== ~ ~ Z ~ o ~ o N c== < ~ ;>-t aAV .nonqna / ~ c;~ ( + 7 \~: · I c; ~ ... - ~ . ~ i1 ~ / ~ c3 \~~ / ~Allll'O<UN .. ~ ", '-- (~J~~ ~.~ -! +jll i . ~ I I' JIll +\ i. 81 i r ) -. / --/ Q. '" o o c: .2 (ij 1: 8- ~ III ~ ~ III 13 Lu Z:a: U L!::l ~ ~ o Sister Cities Blvd Lo o 50+- 15 J~~rO 5f ~rth SOURCE: Crane Transportallon Group 5 SB 101 OHump ~. / L 0 "\ ( ;=-~. \ A \ 25 ~ \ 20-- \ 30 f ~A~ , I I 10 a o / "l:l > = .. .. o -= '" > <a = La 5 25 0 +- 0 J~L.tO :o~ ~ j r ) o \ \ \ iT SB 101 NB 101 ~ Onramp Offramp g ..Cl :l o ~ Figure 14 YEAR 2000 PROJECT TRAFFIC VOLUME INCREMENTS AM PEAK HOUR I PHASE I ONt Y I TERRABA Y PROJECT SEIR CITYOFSOUTH SAN FRANCISCO,CALlFORNIA Wagstaff and Associates ------------~ /' . , ... / '" L....\ ~~ ~ (~ I l. ;=-~ 'j ~~ /, ,/.... ~ i 1 ~'~ ! ~ ! L. ~~"'~J ~..j ~ - ----.. /~, ... ... - e 2~ ...- .~ ~ .. N_ C>. PAlS ap!llHH PAlll uOlluwS It") ...~ ......rJ'J eq.~ ~ =' Z Z .~ 0 ~~ ::E~ ~~ ~rJ'J u< Z~ ~~ I ~I OAV anbnqna ~ ~ ~~ "'~::J L.. \ \ ~g ::JO +-- r.n \ ~ "---m= ~ r.. \\ "'-z~ 0 ~ ~il ~~~ >~ ~5 U < ~~ ~~ :(~ ~~ -4 "\ : 0 0 ~AIS IJO~' L c> o In 0> ....-- 0> .J!L. r'" ) \ ..j~~I/ c--+ '" 0/ ~/ -4 '.; ~ ~ o ~ ~ o o o N ~ < ~ ~ (--- I I I I I ... - - --~ . :: u ~ ~ Ci.i ..-e. 'lI" -e." ~$'~ (ll.;?:: , -4 jl \.. o :;: ;:; <: : .<:lZou - .. :J<:- o..~ ",,,,0 15 uouauaf .. .. ... - -... ... .. lD L.. u ... ~ :c \.J! L. r" :j ~ j 1 .... -. N / =. "0,0/ ~/ I,~ y.) Q <: u :: ~ u .. '" C. :I e '" c: o ~ 8- ~ lIS f:. ~ l! Ll UJ <~ ~ Project ~~~:er~ial 10 45 L 0 .J I 20 -t 25 0 - 190 t .J ~ L. + 10 \ 20 3SJiti 50 - 645 0 35 t 20 Si.ter Cities Blvd L440 5 20 50 - 25 .J~L.+ 0 195J 150 - iti o 30 0 / lOt ~rth SOURCE: Crane Transportation Group 20 35 .J~ ;---- lOt SB 101 OHramp < SB 101 Onramp ~ Figure 16 YEAR 2010 PROJECT TRAFFIC VOLUME INCREMENTS AM PEAK HOUR PHASES I, II AND III /~\ ! -60 \ I /0 i t I i \ " TERRABA Y PROJECT SEIR CITYOFSOUTH SAN FRANCISCO, CALIFORNIA 4 70 ~ 65 - 65 -, ., " iti 405 0 20 "=' > "" ~ o ..c: .. > .. "" ~~\ g .J~L.+O ... :< 385J i i i / 0- 0 0 / 20 " o t /'" 10 SB 101 NB 101 ; Onramp Otframp g- oO = o Wagstatt and Associates ~~ ~ o V\ ~\...II) ... - E '" .. -,:: .,- ",0 ~C/)~ ..... ~ C1I~~ :3Z .~ rT' 0 ~ .... Z :E< ~Ior'ol ~~ U ~.. ZC/) ~~ uy anDnqno ~ C/) /~O ~~\~'J~~ (.J!L.,-Oi\ ~OO I ~ ~o~ 1! ~ ) "~f > ~ >- .--- - / ., c u ::J o -.,. / ",0 ~ 0 "YAIS ll~ ~ ~ ~~o~oo'\ ~< ... \ ~ rTl .J~L..-~ \, ~s: ;J I j r- I U ~ \ = --.... C II) ../ rT1 ~ \ gl "11\, ......"". '" ... .,. / ~"""" ~/ 0 ~ ~ o 1""""l o N ~ < ~ ~ ----------- ", ... - s ~ : ., c ",0 .J!L. .., .. .. .. ~+ LO oS - .. ?~..,~\ ~~ Ijr-I ~ ~ .., - ~~N/ .; / .. pA III alO'lSAes L.. - .. ..- .-~ Ij~ .. .. .., . '" ... .., SlaJJY ,ellualp.all r pa!Dld u ~ c "\ ." .. ii .. u U Co ::l e C!l c .2 1;j I '" .= ~ '" u UJ <~ ~ v - ... ~]:!o:: "0 &~ A: ~< .J! L. ..J ~ - I I I ... I r- I ~_ \ \ 0+ "- " PAIS apl'll!H .., .. ~ ... .J! ~J Ij ~+ ... 0 .., ~ ; e '" .. ...-.: - c ;l .. o ~ "'::- .8aJJY ,elluarp.all pa!Old ." .. ii ~ e/ c c u u ~ u .. ... ~ u .. en u :; :c ... '--.. -.., .J!L. ... ~J I j r- ) \..-.., 0,' ~:::+ m = / I~.. ~' y..) Vl III 'E .g ~ '0 S ~ g ~ ~ 890 L 20 Project Commercial --< 25 80 -190 J~L. ~ m.5 Access _/ , I \ 35 ..J ii~ \ 50 - 645 40 '--- 35 t 435 ~'" / L 400 ' I --H5 ~ 455 550 L 520 90 276C -- 145 JtL.~90 305 ..J 660 - 220, .., \ \ \ .., .:: "" 280..J i i ~ 510 2330 30 .. .. Q ..: .. > . "" Sister Cities Blvd '---_.../ Oyster roint Blvd - .. Q Cl .. < US 101 -~ / 130 ~ 0. f 455 0 -- 0 ! JtL.~O I 1,,\ 2785..J i i ~ o - 40 0 ~' /~ / ..... .., > i:C SB 101 .. > < NB 101 ; Off ramp g ..c:> " Q SOURCE: Crane Transportallon Group Figure 18 YEAR 2010 BASE CASE PLUS PROJECT TRAFFIC VOLUMES AM PEAK HOUR-- PHASES If II AND III ~h TERRA8A Y PROJECT SEIR CITY OF SOUTH SAN FRANClsCO,CALlFOI{NIA Wagstatf and AssOClates oM ... 0 o 0 ~ 0.. ::: ~ - & ;! 2.: ::: :0 ",0 \( ..--------.... I.. I '- "" 0 -~-". I...... _ = L.., ,/ rll.r= \ / CI 1ft ::: .=: \ ..,.J .. ) I E ~::: -:~ \ ! ..j i i r+ / .J ~ l. r ~ " ~__ !.. ~ / \ 1 ~ r,/ . \~::+ - /",,\ \ - - '~ .., ....." ~ \. -~ ... 1 ~,-;g 2~.. %0 · C i ZO: ~ P".I ..0"....8 ~!~\ ~ Ii: I ~ ~ - _g" " ~~~i I11.r~ \ ... V< I +' y ! ~ ~ j i i r ) .....V 1"1""0'''11 ~ -.. - 0, "':; ~ ~;t.lo.ld -..-, -:;~ :. - . - ... :5 ~ .. f'.- , \ ~ \~ i: ~ ~j ~: / ~ ~~ '". / ~c---.--/ . '0 "'~ :-w " " o. "'~ .. ...:)~V '.l~v.,nll'V "- foltlll''''''d. oa .. . PAil 'P!'I1!H .. .. ... o .. '" ~"18 l'OCUIV ~ '/0 ~ 0 L =0.""\ =:r-. +--_ ( .7 ~ l. r =~ ') ! ....ii,.. i ..~-..J I; \ .. - ..,..,. \ =~~ =:") ~ .,.'!> ~" .~'!>.. .~.. ~':! 'L:: /~= . \ -\]) IS 110"1"11 .. ~ :: Q ~ 11 L.. ..Jll.r~ 1 \ =.:::. i ~ ) \~' 0\ CJ:) ~ -' fT' ~ ~...... ~ ~~o ~ ::J :z ...J< o~ >~ u~ ~rJ'J ~~ ~rJ'J << ~:I: ~~ ~I ~S ~o ~~ ~~ rJ'J< ;J~ ...J~ ~~ ~~ CJ:) -4 ~ T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 128 r Boulevard intersection as the volume increase would be less than two percent. (Supplementsllmpact T-2) Year 2010 - Phases I, /I and III. Signals would be provided by the project at the reconstructed Bayshore Boulevard/US 101 southbound hook ramps/project commercial access intersection. r However, the cumulative traffic from Phases I, II and III would further aggravate the Year 2010 Base Case warrant criteria need for signals at the Hillside Boulevard/Chestnut Avenue r intersection, resulting in a significant adverse impact. (Supplemental Impact T-3) e. Project Level of Service Impacts--Studv Intersections Table 16 presents AM and PM peak hour intersection level of service. r Year 2000 - Phase I. No significant impacts were identified during the AM peak hour. Project r volume increases would be less than two percent during the AM peak hour at the U.S. 101 r Southbound Off-Ramp/Northbound Bayshore Boulevard intersection, which would already be r experiencing Base Case LOS F operation if remaining an all-way-stop. During the PM peak hour, all intersections would be operating acceptably with the addition of project Phase I traffic with one exception: Hillside Boulevard/Chestnut Avenue. The project would increase PM r peak hour volumes by more than two percent at this intersection, which would already be experiencing unacceptable (LOS F) operation with Base Case volumes for the stop sign- controlled left turn movement from Chestnut Avenue. This would be a significant adverse impact. (Supplemental Impact T-4) r Year 2010 - Phase I. During the AM peak hour, Phase I traffic would result in significant r adverse impacts at the following location, which would already be experiencing unacceptable r operation with Base Case volumes: . Sister Cities Boulevard/Oyster Point Boulevard/Bayshore Boulevard/Airport Boulevard r (more than a two percent increase in traffic added to Base Case LOS F signalized operation.) (Supplemental Impact T-5) r During the PM peak hour, Phase I traffic would result in significant adverse impacts at the r following locations, which would already be experiencing unacceptable operation without the r project: r . Sister Cities Boulevard/Oyster Point Boulevard/Bayshore Boulevard/Airport Boulevard r (more than a two percent increase in traffic added to Base Case LOS F signalized r . operation.) (Supplementallmpsct T-6) r . Hillside Boulevard/Chestnut Avenue (If this intersection remains unsignalized, more than r a two percent increase in traffic volumes would be added to Base Case LOS F operation r for the stop sign-controlled left turn movement from Chestnut Avenue.) (Supplemental r Impact T-7) r WP51 \548\FSEIR\IV-C-REv.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 129 Table 16 BASE CASE INTERSECTION LEVEL OF SERVICE--(AM) AND PM PEAK HOUR, WITHOUT r AND WITH PROJECT (WITHOUT FL YOVER) Year 2000 Year 2010 Year 2010 Base Case Base Case Base Case & Year 2000 & Project Year 2010 & Project Total Project Intersection Base Case Phase I Base Case Phase I (Phases I, II, III) Signalized r Hillside Blvd/Jefferson StI A- .36' A - .42 A - .42 A - .48 B - .54 South San Francisco Drive (Phase I Access) r Hillside Blvd/Sister Cities A - .43' A - .47 A- .48 B - .51 B - .57 Blvd Sister Cities Blvd/South San N/A N/A N/A N/A A - .42' Francisco Orive/(Phase II Access) r Sister Cities Blvd/Oyster (0 - .72)1 (0 - .74) (F - 1.27) (F - 1.29) (F - 1.60) r Point Blvd/Bayshore Blvd/ C - .59' C - .61 E - .87 E - .89 E - .92 Airport Blvd r Oyster Point Blvd/Dubuque (B - .52)1 (B - .52) (F - 1 .59) (F - 1.59) (F-1.61) r Ave/US 101 NB on-ramp C - .67' C -.68 F - 1 .22 F - 1.22 F - 1.21 r Dubuque Ave/US 101 NB (A - .35)' (A - .35) (D - .82) (0 - .83) (E - .95) r off-ramp/US 101 SB on-ramp A - .43' A - .44 E - .92 E - .92 D - .78 r Bayshore Blvd/US 101 SB (F - 1.51)' r ramps/Project Commercial N/A N/A N/A N/A F-1.1i Access (Phase III) Unsignalized r Hillside Blvd/Evergreen Dr o - 20.92 o - 22.3 C - 13.1 C - 13.2 C - 14.7 r Hillside Blvd/Chestnut Ave F3 F F F F r A-.411 A - .44' A - .44 A - .46 B - .54 r US 101 SB off-ramp/NB (F)4 (F) (F) r Bayshore Blvd (All-Way Stop) (E - .897)' (E - .906) (F - 1.60) (F-1.60) r C - 14.44 C - 15.8 F N/A r AlB - .50' B - .52 E - .961 E - .98 SOURCE: Crane Transportation Group. , Signalized level of service - volume/capacity ratio. 2 Unsignalized level of service/average vehicle delay (in seconds) - eastbound left tum from Evergreen Drive. r 3 Unsignalized level of service - average vehicle delay (in seconds) - eastbound left turn from Chestnut r Avenue. r 4 All way stop level of service - average vehicle delay in seconds. WPS11548IFSEIRIIV-C-REv'S48 T errabay Project City of South San Francisco August 29. 1996 Revised Draft SEIR IV.C. Transportation Page 130 r Year 2010 - Phases I, /I and III. Phase III of the project would include construction of new US 101 southbound on and off hook ramps connecting to Bayshore Boulevard at a signalized intersection that would also serve as the primary access to the project's commercial portion. These ramps would be located at about the same location as the existing southbound off- r ramp connection to Bayshore Boulevard. Provision of a new southbound hook on-ramp along r Bayshore Boulevard as part of project Phase III would remove a substantial amount of Brisbane traffic bound for southbound US 101 that previously would have travelled through the Oyster Point interchange to access the southbound on-ramp at Dubuque Avenue. Thus, r during the PM peak hour, even with the addition of traffic from full Terrabay r development, operation at two of the three Intersections within the Oyster Point r Interchange (I.e., the Oyster Point BoulevardlDubuque Avenue/US 101 northbound on- r ramp and Dubuque Avenue/US 101 northbound off-ramp/US 101 southbound on-ramp r Intersections) would be better with project Phases I, " and 1/1 (and the new southbound r hook on-ramp along Bayshore Boulevard) than without the proJect.' r As shown in Table 16, due to the new southbound hook on-ramp to be installed as part of r project Phase III, the project would reduce unacceptable year 2010 PM peak hour operating r conditions (Le., a beneficial effect) at: (1) the Oyster Point Boulevard/Dubuque Avenue/US 101 r northbound ramps intersection from a Base Case 1.22 V/C ratio without the project to a 1.21 r V/C ratio with the project, and (2) the Dubuque Avenue/US 101 northbound off- r ramp/southbound on-ramp intersection from a .92 V/C ratio (LOS E) without the project to a r .78 V/C ratio (LOS D) with the project. During the AM peak hour, traffic from Phases I, II and III would result in significant adverse impacts at the following locations: · Sister Cities Boulevard/Oyster Point Boulevard/Bayshore Boulevard/Airport Boulevard r (more than a two percent increase in volume added to Base Case LOS F operation.) r (Supplemental Impact T-B) r · Oyster Point Boulevard/Dubuque Avenue/US 101 northbound on-ramp (more than a two r percent increase in traffic added to Base Case LOS F operation.) (Supplemental r Impact T-9) r · Dubuque Avenue/US 101 northbound off-ramp/US 101 southbound on-ramp (acceptable r base case LOS D operation is changed to unacceptable LOS E operation with the r addition of project traffic) (Supplementsllmpact T-10) . Bayshore Boulevard/US 101 southbound on- and off-ramps/project commercial access r (LOS F operation and lack of sufficient turning lane vehicle storage for this new r intersection). (Supplemental Impact T-11) 'The project commercial area would also be accessed via two right turn in/right turn out driveways along Bayshore Boulevard. one north and one south of the commercial area's signalized access. WP51 \548\FSEIRI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 131 r During the PM peak hour, traffic from the total project would result in significant adverse r impacts at the following locations: r · Sister Cities Boulevard/Oyster Point Boulevard/Bayshore Boulevard/Airport Boulevard r (more than a two percent increase in volume added to Base Case LOS E operation, r resulting in a change to LOS F operation). (Supplemental Impact T-12) · Bayshore Boulevard/US 101 southbound on- and off-ramps/project commercial access r (LOS F operation for this new intersection). (Supplemental Impact T-13) · Hillside Boulevard/Chestnut Avenue (If this intersection remains unsignalized, more than r a two percent increase in traffic volumes would be added to the Base Case LOS F operation for the stop sign-controlled left turn movement from Chestnut Avenue.) r (Supplemental Impact T-14) 1. Project Freeway Link Impacts Table 17 presents year 2000 and 2010 PM peak hour project traffic impacts on US 101 freeway link operation. Year 2000 - Phase I. Phase I traffic would not significantly affect PM peak hour operation of US 101 in 2000. Project traffic would not change level of service of any analyzed freeway r segment and would not increase volumes by two percent or more along the three segments r (north of Sierra Point and south of Oyster Point) projected to experience LOS F Base Case r operation in 2000. Year 2010 - Phase I. Phase I traffic would not significantly affect PM peak hour operation of r US 101 in 2010. Project traffic would not increase volumes by two percent or more along r analyzed segments, which are all projected to experience LOS F Base Case operation in r 2010. Year 2010 - Phases I, /I and III. Traffic from Phases I, II and III would increase PM peak hour r peak direction Base Case VIC ratios by more than two percent along the US 101 freeway r segments between the Oyster Point interchange and the South Airport Boulevard interchange, r locations which are projected to already experience LOS F Base Case operation in 2010 r without the project. This would represent a significant adverse project impact. r (Supplemental Impact T-15) a. Project Freeway Ramp Impacts Table 18 presents project impacts on year 2000 and 2010 AM and PM peak hour operation of the Oyster Point interchange ramps and the southbound off-ramp to Bayshore Boulevard. WP511548\FSEIRIIV-C-REV.548 T errabay Project Revised Draft SEIR City of South San Francisco IV.C. 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Transportation Page 133 10 ~ C I'll ~ ~ '0 I'll g- U >- I'll ~ ..c 01 I ~ 0'> en ai o N 1:: 8. Ql a: 10 .0 Ql a. CJ) CIl a: f0- ci ~ o c!5 c o "ia 1:: 8. I/) C I'll .= CD c I'll U .~ o I'll a. I'll I/) 0 1/)" Ql Ql o I/) o I'll <C Ql - t; .!!! c 0'- ...." Ql Ql E c E .21 o I/) u~ >-Ql I'll C .D I'll ~- .... >- Ql .... fo-~ (U.~ -0 I'll ~ E CIlo Ql-= ]g- I/) I'll >-.... I'll . CIl= o o .... - 0 . a. CD :; E c o I'll I'll ~'i- ....= ~ Ql 0 I'll a." == I/) C )( .... ~ ~ ~.B I'll CD ~ ,g Ol~o. c 0 E Q) I/) I'll ~ :c 'i I'll CD C e...zo w U a: ::> o CJ) . . . . . . T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 134 Table 19 PROJECT IMPACTS TO COLMA INTERSECTIONS Intersection Serramonte Blvd/ Hillside Blvd Serra monte Blvd/EI Camino Real Serramonte Blvd! Junipero Serra Blvd/ 1-280 northbound onramp Total Existing- PM Peak Hour Volumes Enterina Intersection 1,197 3,043 3,463 Traffic Added by Terrabay Phase I (2000) Phases I, II and III (2010) % Added % Added Volume to Existina Volume to Existina 20 1.7% 50 4.2% 15 .5% 1.3% 40 10 .3% .7% 25 SOURCE: Crane Transportation Group and the city's Cypress Hills DEIR, May 1994. . 1992 and 1993 volumes, Cypress Hills DEIR, May 1994. WPS11548\FSEIR\JV-C-REV.S48 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 135 Year 2000 - Phase I. Phase I AM or PM peak hour traffic would not significantly affect any of the four US 101 freeway ramps in the year 2000. Year 2010 - Phase I. Phase I AM or PM peak hour traffic would not significantly affect any of the four US 101 freeway ramps in 2010. Year 2010 - Phases I, 1/ and 1/1. During the 2010 AM peak hour, total project traffic would r result in significant adverse impacts (more than a two percent increase in volume to over r capacity Base Case operation) at two ramp locations: the southbound off-ramp to Bayshore r Boulevard and the northbound off-ramp to Dubuque Avenue. (Supplemental Impact T-16 r andSuppremenmllmpact~1n During the 2010 PM peak hour, traffic from Phases I, II and III would not increase traffic volumes at any ramp above capacity. The addition of project vehicles would, however, r increase volumes by more than two percent at the already over capacity northbound on-ramp r from Oyster Point Boulevard. (Supplemental Impact T-18) h. ProJect Impacts on Colma Intersections The city of Colma has expressed concern regarding project traffic impacts at three intersections along Serramonte Boulevard: at Hillside Boulevard, EI Camino Real and Junipero Serra Boulevard--1-280 northbound on-ramp. Projections were made as to the likely amount of PM peak hour Phase I and Phases I, II and III traffic that would likely travel through each of these intersections. Table 19 presents the total amount of traffic' passing through each of these intersections, the amount of project traffic expected to pass through each intersection and the percent traffic added by the project. The percentages shown in Table 19 attributable to project traffic would be 10 to 20 percent lower if an approximately one percent per year growth in traffic volumes were added to the existing traffic volume base to the years 2000 and 2010. No significant impacts were identified for year 2000 or 2010 Base Case plus Phase I traffic conditions. However, in 2010 with Phases I, II and III, the Serramonte Boulevard/Hillside Boulevard intersection would be expected to experience an approximately four percent increase in traffic volumes, which would be considered a significant adverse impact. r (Supplemental Impact T-19) 4. SUPPLEMENTAL MITIGATION NEEDS Transportation impact mitigation needs have changed from those identified in the 1982 EIR r (see Table 12). Several of the mitigations identified in the 1982 EIR were subsequently '1992 and 1993 traffic volumes from the Cypress Hills DEIR, May, 1994. WP51 \S48IFSEIRIIV-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 136 incorporated into the specific plan and development agreement and have been completed as part of Phase I roadway improvements. These completed mitigations include: . construction of Sister Cities Boulevard (referred to as the Hillside Extension in the 1982 EIA) between its intersections with Hillside Boulevard and Bayshore Boulevard; r . widening of Hillside Boulevard (renamed Hillside Boulevard Extension) and creation of r local traffic lanes and a landscaped buffer separating local access movements (along r Hillside Boulevard) from higher speed traffic along Hillside Boulevard Extension between Sister Cities Boulevard and Lincoln Street (the segment fronting the project site); . signalization of intersections at the new Oyster Point interchange and the Hillside r Boulevard Extension/Jefferson Street, Hillside Boulevard/Sister Cities Boulevard, Sister Cities Boulevard/South San Francisco Drive and Sister Cities Boulevard/Airport r Boulevard/Bayshore Boulevard intersections; and r . removal of the existing stop signs for Hillside Boulevard Extension traffic at the Hillside r Boulevard Extension/Kearny Street and Hillside Boulevard Extension/Irving Street intersections. (A newall-way stop sign was installed at the Hillside Boulevard/Lincoln Street intersection to permit vehicles to exit Lincoln Street under conditions of heavy r truck traffic, high speeds, and limited line-of-sight to the west along Hillside Boulevard at this location.) Mitigations recommended in the 1982 EIA that are still proposed in this SEIA include: . reconstruction of the US 101 southbound "scissors" off-ramp to Bayshore Boulevard as a hook off-ramp (however, the recommended lane geometries at this location have changed due to changes in projected traffic volumes) and construction of a new hook on- ramp for southbound traffic, both in conjunction with project Phase III; . signalization of the Hillside Boulevard/Chestnut Avenue and US 101 southbound off- ramp/northbound Bayshore Boulevard intersections; and r . implementation of transportation system management (TSM) measures. Additional mitigations have also been recommended in this SEIA for identified significant impacts at the Serramonte Boulevard/Hillside Boulevard intersection in Colma and at the northbound off-ramp from US 101 to Dubuque Avenue. These remaining 1982 EIA and new SEIA mitigation needs are described below. a. Base Case Mltlaatlon Needs Without Prolect Figure 20 presents Year 2000 Base Case mitigation needs without the project. Figure 21 r presents Year 2010 Base Case mitigation needs without the project and without a southbound r to eastbound flyover offramp. WP511548IFSEIRI/V-C-REV.S48 ... - & ~.:: .. - ...0 ~ ;; '" c: C l>O .~ Vi ;; .~ :i ~ .. z Q @.... ~../+ ~ \\ ( J lllll'l t T \ \, . : J r \'i -' i J ~~'~ ~...v ono:qna \:~ zo ... - & 2 : .. ~ ...0 ~ 5 ~ G . c: '; zo '0 .. p.-,s ..o"....s -0 .. -0 .. .. z (----- --- I ~ I iD I : I I u Q ~ ~ ... : ... '" :; c '" .--------- ~ ~ o ~ l,oaJ1V t= l.Jy, ( -- ;! \~ iii(/ ~ ~ ~ v; Q ~ = .. .. ... .. iD .. ~ :: :Jlll + ( --4jilr I ~. 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"""" ~j C/)~ <~ uO ~~ C/)~ ~~ 00 S::t N~ ~~ <~ ~ ~ Q. ::l o (; c: o 1ii i '" ~ ~ '" u ~ ~ <g ~ T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 139 (1) Intersection Sianalization r The following Base Case physical mitigations should be implemented by the city to reduce significant impacts identified for anticipated Base Case future traffic conditions (without the project) to less than significant levels, with fair share contributions from all Base Case developments: (a) Year 2000: r . Hillside Boulevard/Chestnut Avenue. Signalize. Coordinate (sequence) this signalization with the nearby Hillside BoulevardlStonegate Drive signal. Resultant PM r peak hour operation: LOS A r Note: Alternatively, associated engineering evaluation may also indicate that the Stonegate Drive signal (and associated sequencing) is no longer needed and that instead of signal sequencing, the Stonegate signal can be replaced with a stop sign on the Stonegate approach only (i.e., if the new Chestnut Avenue signal will provide sufficient gaps in eastbound Hillside Boulevard traffic flow to allow safe stop sign- r controlled turn movements from Stonegate Drive). Monitoring/evaluation mayor may not also indicate that a change in the nearby all-way-stop-sign-controlled Hillside Boulevard! Lincoln Street intersection--i.e., removal of stop signs on the Hillside Boulevard r approaches, along with restrictions allowing inbound right turns to Lincoln Street only-- r may be possible. . US 101 southbound off-ramp/northbound Bayshore Boulevard. Signalize when warranted and add second off-ramp intersection approach and departure lanes. r Resultant peak hour operation: LOS B in the AM peak hour; LOS A in the PM peak hour. (b) Year 2010: r . Hillside Boulevard/Chestnut Avenue. Signalize. Resultant PM peak hour operation: LOS A . US 101 southbound off-ramp/northbound Bayshore Boulevard. Signalize when r warranted and add second off-ramp intersection approach and departure lanes, as well r as second northbound Bayshore Boulevard approach and departure lanes. Resultant r peak hour operation: LOS D in the AM peak hour; LOS A in the PM peak hour. (2) Intersection Geometric Improvements (Base Case without Proiect) (a) Year 2000: . US 101 southbound off-ramp/northbound Bayshore Boulevard. Add a second lane to the southbound off-ramp and signalize the intersection. Resultant peak hour r operation: LOS B in the AM peak hour; LOS A in the PM peak hour. WP51 \548\FSEIRI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 140 (b) Year 2010: . Sister Cities Boulevard/Bayshore Boulevard/Airport Boulevard/Oyster Point r Boulevard. Implement both of the following improvements: r (1) Complete Maximum Practical Intersection Lane Addition Improvements. Complete r the following: r Airport Boulevard northbound - restripe and provide 1 left-turn/2 through/1 right-turn lane r Oyster Point Boulevard westbound - add a second through lane (this would require r widening the freeway overpass) r Sister Cities Boulevard eastbound - add a second left-turn lane r Resultant peak hour operation: LOS F in the AM peak hour; LOS C in the PM peak r hour; Le., these maximum practical intersection lane improvements would improve peak r hour operation, but would not provide acceptable AM peak hour operation (see Figure r 21). r (2) Construct Southbound to Eastbound Flyover Off-ramp. Construct a southbound to r eastbound flyover ramp as described above in order to provide acceptable AM peak hour r operation. r A US 101 southbound flyover off-ramp would connect with eastbound Oyster Point Boulevard to the east of the Dubuque Avenue intersection.' (Figures 22 and 23 present 2010 AM and PM peak hour Base Case traffic volumes, respectively, without the project and with the flyover. Figure 24 presents 2010 Base Case intersection approach lane needs with the flyover.) r No additional approach widening (such as the measure listed above) would be required r with the flyover. r Resultant peak hour operation: LOS B in the AM peak hour; LOS C in the PM peak hour. Note: As can be seen by comparing Figures 21 and 24, provision of the southbound off- ramp flyover significantly reduces the level of improvement (Le., number of new lanes) r needed for the year 2010 Base Case conditions at the Sister Cities Boulevard/Bayshore r Boulevard/Airport Boulevard/Oyster Point Boulevard intersection. , Such a southbound off-ramp flyover was proposed and approved as part of the recently completed Oyster Point interchange reconstruction project, but was not constructed due to cost reduction measures. The flyover has been identified as an "ultimate" mitigation need for the traffic impacts of r cumulative development in the vicinity, with or without the Terrabay project. WP51 \548\FSEIR\lV-C-REV.548 T errabay Project City of South San Francisco August 29. 1996 Revised Draft SEIR IV.C. Transportation Page 141 r . Oyster Point Boulevard/Dubuque Avenue/US 101 northbound on-ramp. Implement r both of the following improvements: r (1) Complete Maximum Practical Intersection Lane Addition Improvements. Complete the following: r Oyster Point Boulevard westbound - add a second right-turn lane (this would require r widening the Oyster Point Boulevard bridge across the railroad) r Oyster Point Boulevard eastbound - add one additional through lane (this would require r widening the freeway overpass) r Resultant peak hour operation: LOS F in the AM peak hour; LOS F in the PM peak r hour; Le., these maximum practical intersection lane improvements would improve AM r and PM peak hour operation, but not to acceptable LOS levels (see Figure 21). r (2) Construct Southbound to Eastbound Flyover Off-ramp. Construct a southbound to r eastbound flyover offramp. r Resultant peak hour operation: LOS D in the AM peak hour; LOS F in the PM peak r hour; Le., this measure would provide acceptable AM peak hour operation, but would not r provide acceptable PM peak hour operation, even with the lane addition improvements r listed above (see Figure 24). . US 101 Southbound Off-Ramp/Northbound Bayshore Boulevard. Implement one of the following alternative mitigations: (1) Complete Intersection Improvements. Add a second lane to the southbound off- r ramp approach and a second lane to the northbound Bayshore Boulevard approach. r Signalize the intersection (see Figure 21). r Resultant peak hour operation: LOS D in the AM peak hour; LOS A in the PM peak hour. r (2) Construct Southbound Flyover Off-ramp. Provide a southbound to eastbound r flyover off-ramp as described above (see Figure 24). In addition, provide a second off- r ramp approach lane and signalize the intersection. r Resultant peak hour operation: LOS A in the AM peak hour; LOS C in the PM peak hour. . Dubuque A venue/US 101 northbound off-ramp - southbound on-ramp. Add a second left-turn lane to the northbound Dubuque Avenue approach (see Figure 21). WP51 1548\FScIRI/V-C-Rc V. 548 950 \ .." US 101 ". ~, / L '00 ' / +- 185 r- '55 'I' ,~ / 5'5 \ '70 685 +- 120 \ J~L. r-90 \ ( "l:l > cc 210 .J 1000 - 1851 "I' Iii 105 2330 30 "l:l > cc - (; g. .. < US 101 \ ... 2400 -.J 0- Iii '0 0 65 SB 101 Onramp 60 ~ /' ... > NB 101 < Offram p ~ 0" =' .0 '" &:l ~rth SOURCE: Crane Transportation Group Figure 22 YEAR 2010 BASE CASE TRAFFIC VOLUMES WITHOUT PROJECT AM PEAK HOUR-- WITH FL YOVER TERRABA Y PROJECT SEIR ClfY OF SOUTH SAN FRANCISCO, CALIFORNIA Wagstatt and Associates ~ '" ;) (ili ~=-=; ~ ; ) PAll 'P"lIIH ",/"~ h.... .. ",.. B=S --: .J ~ L. ;:-::::: ijr- .. .. =a: ------- PAil ..0'1....1 ~..q..a ... 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C. :> o c'3 l: .2 iij I '" f:. ~ '" Q uJ <~ ~ III III -s .~ . .:( "Cl e ~ ~ ~ T errabay Project City of South San Francisco August 29. 1996 Revised Draft SEIR IV.C. Transportation Page 145 r Resultant PM peak hour operation: LOS E; Le., these maximum practical lane addition r improvements would not provide acceptable PM peak hour operation. r The southbound f1yover off-ramp mitigation would not significantly affect (mitigate) r operation at this intersection. r (3) Freeway Link Improvements (Base Case without Proiect) (a) Year 2000: . Caltrans does not plan to add additional travel lanes to the segment of US 101 through and just north of South San Francisco by the year 2000. Therefore, mitigation of projected unacceptable commute peak period operational impacts would require r voluntary implementation of a combination of transportation demand management (TDM) r and transportation system management (TSM) measures to reduce peak hour demand. Such measures should include incentives to car/vanpool, increased transit availability, provision of flex time working hours for employees, expansion of telecommuting, etc. r The city shall continue to cooperate with MTSMA in its efforts to encourage and foster r voluntary TDM and TSM measures in the Terrabay, East-of-101, and other employment- r intensive development areas in order to reduce commute peak hour automobile travel on r the local freeway network. Bus/shuttle access to CalTrain and BART shall be promoted. (b) Year 2010: · Same mitigation as for year 2000 Base Case without Project, above. (4) Freeway Ramp Improvements (Base Case without Project) (a) Year 2000: No significant impacts identified; no mitigation measures are required. (b) Year 2010: . Southbound Off-ramp to Bayshore Boulevard. Add a second off-ramp lane connection to the southbound freeway mainline and an extended deceleration lane along the freeway mainline. Resultant AM peak hour operation: Under Capacity. . Northbound Off-ramp to Dubuque Avenue. Add a second off-ramp lane connection to the northbound freeway mainline. Resultant AM peak hour operation: Under Capacity. r . Northbound On-ramp from Oyster Point Boulevard. No freeway ramp improvements r would be necessary, assuming implementation of the TSM measures described below r under section a(5). Implementation of the TSM measures alone would be expected to r reduce this impact to a less than significant level. Resultant PM peak hour operation: r Under capacity. WPS1 \548\FSEIRIIV-C-REV.S48 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 146 r (5) Transportation System ManaQement Measures r Maximum allowable levels of service after mitiaation at those intersections for which significant r Base Case impacts have been identified are presented in Table 20. As shown by these r exhibits, the maximum practical physical mitigations shown for the year 2010 Base Case r (without project) would still not provide acceptable operation for Base Case (without project) r volumes at two intersections: the Oyster Point Boulevard/Dubuque Avenue/US 101 r northbound on-ramp and Dubuque Avenue/US 101 northbound off-ramp/southbound on-ramp r intersections. However, the analysis does indicate that the year 2010 Base Case impacts of r these two intersections Q2!l be further reduced to less than significant levels through r implementation of voluntary Transportation Demand Management (TDM) measures for r future new employment intensive uses developed in the East-of-101 vicinity. r A recent state legislative action invalidated Bay Area Air Quality Management District r (BAAQMD) Regulation 13, Rule 1, which had mandated employer-based average vehicle r ridership reductions in the air basin, and which provided the basis for local imposition of TSM r requirements, including the city's TSM ordinance. With the invalidation of BAAQMD r Regulation 13, Rule 1, future TSM-based vehicular trip reductions in the air basin can no r longer be mandated; rather, they must now be achieved on a voluntary, individual employer r basis. r The Multi-City TSM Agency (MTSMA) is a Joint Powers Authority created in 1991 between the r cities of Brisbane, Colma, Daly City, Half Moon Bay, Millbrae, Pacifica, San Bruno, and South r San Francisco. The mission of the MTSMA is to reduce traffic congestion and improve air r quality through use of T8M strategies that reduce automobile commute trips. Based on recent r surveys of employers and commuters in the CMA region following the invalidation of r Regulation 13, Rule 1, including a 1996 telephone survey of commuters by RIDES for Bay r Area Commuters, Inc.,1 the MTSMA believes that voluntary TSM efforts can be expected to r have a continuing substantial effect in reducing future peak period vehicular use on the study r area roadway system.2 r The EIR authors and the EIR transportation engineer have determined that, in addition to the r TSM-based vehicular trip reductions already reflected in the' case study based trip generation r rates used in this traffic analysis (approximately 6 percent), an additional vehicular trip r reduction of at least 12 percent can be anticipated in the projectlEast-of-101 vicinity due to r continued voluntary TSM activity in the future. This assumption is based upon discussions r 1RIDES for Bay Area Commuters, Inc., Commute Profile '96, July 1996, MTSMA Region r Supplement, based on an April 1996 telephone survey of commuters. r 2Telephone conversation with Angela Rae, Executive Administrator, MTSMA; August 16 and 19, r 1996. WP51 1548\FSEIRI/V-C-RE V. 548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 147 Table 20 INTERSECTION LEVELS OF SERVICE AFTER MITIGATION--(AM) AND PM PEAK HOUR Year 2000 Year Base Case 2010 Base Year 2010 Year 2000 & Project Year 2010 Case plus Base Case plus Intersection Base Case ( Phase I) Base Case Phase I Phases I, II, III r Supplemental Impact T-2 r SB US 101 off-ramp/ (B - .56)1 (B - .56)1 (D - .80)2 (D - .80)2 r NB Bayshore Blvd A - .482 A - .492 r (A - .43t (A - .43)F r (C - 65f (C - .67)F r Supplemental Impact T-5/T-6/T-8/T-12 r Sister Cities Blvd/ (B - .57t (C - .59t (D - .81t r Bayshore Blvd/Airport C - .703 o - .723 D - .833 Blvd/Oyster Point Blvd r Supplemental Impact T-9 r Oyster Point Blvd/ (0 - .85)4F (0 - .85)4F (E - .86)4F r Dubuque Ave/US 101 F - 1.084F F - 1.084F E - 1.004F NB on-ramp r Supplemental Impact T-10 r Dubuque Ave/US 101 (E-.94)5/(0- .80)6F r NB off-ramp/US 101 E - .8'? E - .885 o - .785 SB on-ramp r Supplemental Impact T-11/T-13 r Bayshore Blvd/US 101 (D - .80r r SB ramps/Project D - .857 Commercial Access (Phase III) r With Voluntary TDM'" r Supplemental Impact T-9 r Oyster Point Blvd/ (0 - .81 )4F (0 - .82)4F (D - .82t r Dubuque Ave/US 101 F - 1. 034F F - 1 .034F E - .954 NB on-ramp r Supplemental Impact T-10 r Dubuque Ave/US 101 (0 - .78)5 (D - .78)5 (E - .89)5 r NB off-ramp/US 101 E - .865 E - .865 0- .715 SB on-ramp r SOURCE: Crane Transportation Group, Wagstaff and Associates. r "Note. For Supplemental Impacts T-9 and T-tO, the peak hour LOS (V/C) figures in Table 20 indicate r that the recommended maximum practical physical improvements alone will not reduce the peak hour r LOS (V/C) figure to less than significant levels. However, the analysis does indicate that the year 2010 r Base Case plus Project effects on these two intersections can be reduced to less than significant levels r through implementation of voluntary TranSpOrtation Demand ManaQement (TOM) measures for the WP511548\FSEIRIIV-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 148 Table 20 (cont.) r project and other future new employment intensive uses developed in the area. The V/C ratios and r LOS figures in this table for the "with TOM" mitigation scenario include a 12 percent reduction in year r 2010 peak period trips for future new employment intensive uses due to anticipated voluntary TOM r measures to reduce auto use. For more explanation, see Appendix C. Add 2nd southbound lane to off-ramp/signalization and extended deceleration lane on freeway. r 2 Add 2nd southbound lane to off-ramp/second northbound lane to Bayshore Boulevard/signalization. r F With f1yover off-ramp. r 3 Restripe the NB Airport Boulevard approach to provide 1 left, 2 through and 1 right turn lane. r 4 Add 1 through lane on EB Oyster Point approach and a second right turn lane on WB Oyster Point r approach. r 5 Add 2nd left turn lane on northbound Dubuque approach with or without flyover mitigation. r 6 Restripe northbound off-ramp intersection approach to provide two exclusive left turn lanes and one r combined left/through/right turn lane. Sign off-ramp to inform drivers which left turn lane to use r depending upon desired turn movement at Oyster Point Boulevard. r 7 Add second through lane on project driveway EB approach. Second NB and SB left turn lanes also r recommended due to heavy left turn movements on both approaches. EB = Eastbound WB = Westbound NB = Northbound SB = Southbound F = with flyover L = left turn lane T = through lane R = right turn fane TR = combined through/right turn lane WP51 \548\FSEIRI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 149 r with MTSMA staff,' consideration of the 1996 telephone survey by RIDES for Bay Area and r San Mateo County commuters, and consideration of local project area and East-of-101 vicinity r conditions with respect to land use mix, employer characteristics (the mix of large and small r employers), transit provision, BART proximity, and CalTrain proximity. (See Appendix C for r the specific rationale for this TSM-based additional 12 percent peak period automobile use r reduction assumption.) r Therefore, the city shall continue to cooperate with MTSMA in its efforts to foster continued, r voluntary TSM measures in the East-of-1 01, and other employment-intensive development r areas of the city as a mitigation measure for all Year 2010 Base Case peak period roadway r system operational impacts identified in this EIR. r Assumed Mitigation Result: a 12 percent reduction in anticipated peak period automobile use r by future new employment intensive development in the East-of-101 area for the Year 2010 r Base Case (see Appendix C herein). b. Base Case Plus Project Mltlaatlon Needs (1) Intersection Sianalization (a) Year 2000 - Phase I: (Supplemental Impact T-1) Hillside Boulevard/Chestnut Avenue. With project Phase I, r signalize this intersection. Resultant PM peak hour operation: LOS A. (b) Year 2010 - Phase I: (Supplemental Impact T-2) Hillside Boulevard/Chestnut Avenue. For each project phase, r provide a fair-share contribution towards signalization of this intersection (i.e., with Phase I, Phase II and Phase III) Resultant PM peak hour operation: LOS A. US 101 Southbound Off-ramp/Northbound Bayshore Boulevard. Provide a fair-share r contribution towards signalization, widening the off-ramp to provide second approach and r departure lanes, and widening Bayshore Boulevard to provide second northbound approach r and departure lanes (with Phase I, or Phases I and II). Resultant peak hour operation: LOS r D in the AM peak hour; LOS A in the PM peak hour. With a flyover off-ramp in operation, r only signalization and widening of the off-ramp to provide second approach and departure r lanes would be required. Note: Bayshore Boulevard is within the Brisbane city limits. Mitigations involving improvements to Bayshore Boulevard must be coordinated with the city of Brisbane. r llbid. WP51 \548\FSEIRI/V-C-REV.S48 T errabay Project City of South San Francisco August 29. 1996 Revised Draft SEIR IV.C. Transportation Page 150 (c) Year 2010 - Phases I, II and III: (Supplementa/.lmpact T-3) Hillside Boulevard/Chestnut Avenue. Same mitigation as r Supplemental Impact T-1. Resultant PM peak hour operation: LOS B. (2) Intersection Geometric Improvements (a) Year 2000 - Phase I: . (Supplemental Impact T-4) Hillside Boulevard/Chestnut A venue. Same mitigation as Supplemental Impact T-t. (b) Year 2010 - Phase I: r . (Supplemental Impacts T-5 and T-6) Sister Cities Boulevard/Bayshore Boulevard/Airport Boulevard/Oyster Point Boulevard. r The southbound to eastbound flyover off-ramp mitigation only, as recommended for 2010 Base Case (without project) conditions, would also provide acceptable operation for 2010 Base Case with proiect Phase I conditions. Project Phase I should provide a fair share r contribution towards the flyover. r Resultant peak hour operation: LOS C in the AM peak hour; LOS 0 in the PM peak hour. r . (Supplemental Impact T-7) Hillside Boulevard/Chestnut Avenue. Implement mitigation recommended for Supplemental Impact T-t. (c) Year 2010 - Phase I, II and III: Year 2010 Base Case plus project Phases I, " and III mitigation needs without and with r the southbound off-ramp flyover are diagrammed in Figure 25. r . (Supplemental Impacts T-B and T-12) Sister Cities Boulevard/Bayshore Boulevard/Airport Boulevard/Oyster Point Boulevard. r Construct Southbound Flyover Off-ramp. With a southbound to eastbound flyover off- ramp, the geometrics recommended at this intersection for the 2010 Base Case r conditions with the flyover and without the project would not provide acceptable operation r with full project development. r To mitigate this deficiency, restripe the northerly Airport Boulevard approach to include r one left, two through, and one right-turn lane, with a fair-share cost contribution from r each project phase (Le., no lane additions or approach restriping). WPS1 \548\FSEIRI/V-C-REV.S48 It')' -' C'l~~ ~~~ ~~> fi:OO ~~ ~ti > -------- -, ~ l-04 ~ llll r Z 0 - - /'03 A / .., : ~ CJ) CJ) \ -111th/ /~~!}/ +.7f- \~~ ~ ~ ~ / I~:, ~ i.,tr-'\~. ~~ ~'o .~o -; ~_/~ PAIlI aJol(UWg ~ ~ ~ E= -]- _- M< t;~ /J II C-** \ ~ C,;) ... u< I'" ~.- I < l-04 : J~ ~~ \**2iti~/ ~~ \~~ I ~ ,," c i'l 6- ~~ u c: .. oJ .... c: u .. '03 " u ... .. Z ~ . .. .. ;: u c: . c: oJ S .. .. .. 20J c: -.c: .. c: ....00 ;;; .;: .. " ~ ...2 '03 ;:.c: u .... ;"" Z < .. Q . . 1lIl_ (j) + I I .. - c:l - '" ::l " <.l :I 1S co:: o ]-5 ] : ~i o .. <.l 15 ~<ii II . -= u l-04 l-04 l-04 ..'I> 0 <0" z ~~i < l-04 l-04 ... l-04 ~) CJ'J ~ CJ'J < :I: ~ Jlll + . --4 1 ir / -. / ~ ~ ;;; -. c: .. 0 '" ... .c:~ - ... " c: 0" "'~ ... '" .U))V I.H\Jap~.a~ ~.J.~U.ld ~ > ;; '* '* - - r- ... //~~ ~ PAIlI ap!I\I!H Q c: .. :: ~ .. > '" Q. ::l o (; co .2 1;; t: 8- ~ '" ~ Ql co '" U UJ <~ ~ T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 152 r Figures 26 and 27 present AM and PM peak hour Base Case plus Total Project (Phases I, II and III) traffic volumes, respectively, with the proposed flyover mitigation. r r . r r r r r r r r r r r r r r r r r r r r r r r r r r r r Resultant peak hour operation: LOS D in the AM peak hour; LOS D in the PM peak hour. (Supplementsllmpact T-9) Oyster Point Boulevard/Dubuque Avenue/US 101 northbound on-ramp. With provision of the southbound to eastbound flyover off~ramp, an additional right-turn lane on the westbound Oyster Point Boulevard intersection approach, and an additional eastbound through lane, neither AM nor PM peak hour operation at this intersection could be improved to acceptable levels. Resultant peak hour operation: LOS E (unacceptable) in the AM peak hour; LOS F (unacceptable) in the PM peak hour. As explained previously, the project would not contribute to but rather would reduce Base Case unacceptable PM peak hour operation at this intersection due to diversion of traffic to the new southbound hook on-ramp to be installed as part of project Phase III. However, in the AM peak hour, the intersection level of service at this intersection, after these geometric improvements, would be LOS E (a .86 V/C ratio), versus LOS D (.85 V/C ratio) without the project; Le., a 0.1 increase in V/C ratio after mitigation, which would still represent a significant impact (more than a two percent increase in traffic volume). (Supplementallmpsct T-10) Dubuque Avenue/US 101 northbound off-ramp/US 101 southbound on-ramp. A fair-share contribution should be provided from each project phase towards recommended Base Case improvements (addition of a second left turn lane to the northbound Dubuque Avenue approach.) However, this lane addition would not provide acceptable AM peak hour operation with the project. The recommended mitigation would reduce theV/C ratio from .95 to .94 in the AM peak hour without significantly increased TDM measures, and down to .89 (LOS E) with increased TDM measures. Provision of the flyover off-ramp would have no mitigating impact at this location. Resultant peak hour operation: LOS E in the AM peak hour; LOS D in the PM peak hour An additional potential improvement would be the restriping of the northbound off-ramp intersection approach to provide two exclusive left turn lanes and a combined left! through/right turn lane. Signing would need to be provided for off-ramp vehicles identifying which left turn lane to occupy in order to be directed to the appropriate turn lane on Dubuque Avenue at Oyster Point Boulevard. No second left turn lane would be needed at the northbound Dubuque intersection approach. WP51 \548\FSE/RI/V-C-REV.548 /~, 890 20 \ 25 80 - 190 \ j ~ ~ t 360 35 j ~ Project Commercial / Access / ~( US 101 ~, / j. / L 400 L 520 550 90 655 - 145 j~~ t90 / I I -HS ,- 455 y Sister Cities Blvd j. 305 -! 660 - 220 t -a > "" ... +-, j. ,.... 280~ I I I 1065 - 510 2330 130 , 30 'f us .. \ ... I j. ,.... 0 101 \ 2785 -! i i e \ 0- 40 0 < 85 60 ---, " /" / SB 101 Onump .. > NB 101 < Offramp ~ '" " ~ " Q ~rth Figure 26 YEAR 2010 BASE CASE PLUS PROJECT PHASES I, II AND III TRAFFIC VOLUMES, AM PEAK HOUR-- WITH FL YOVER SOURCE: Crane Transportation Group TERRABA Y PROJECT SEIR CITY OF SOUTH SAN FRANClsCO,CALlFOI<NIA Wagstatf and Associates -------- /-------- ...,::: L:, / L.. /" ~ ~::: .- .... 1ft \ 1ft ""... +- = \ (..J ~ L. .-;., ) ,.J ~ L. .- ~ \ \ !J r l - ::..-=: ~ ! r / "'. :;: 5:;: \ ~+ = /'\ ~ -~ ~ "f ~.- l 4~ ~- /!' o o '" ;:J ~uv ~"r"~"a '( / - ! :;:. ~AIII'OCl"V ... ..0 i = ~ L =0 /,...- ...-- .J ~ L. .-:~ \ I :;; ~ ~ t r+ ) _ -.... 1ft fl\ -.. 0 11ft .... ~+ ":: PAil uoqlul .. L.. a ... h. ....,.. ~rl. ;:-::t: ~;:.J ~ t r+ .. - .. - 0' 0 11ft ~+ . =" It.))V 'W"UIOII''''' ~)aloJ:cI . .. U .. . iii _ 1~ ~ : \ ;~ ) ~ " .. 0 "'.. =! " " 0" ., ~ .. f?!\ \ ~:::~ ~ ~ ) '~ L., -.. .J~L.'-~ :~ -q r+ .. ----.. 1ft 0 :: .. :: PAlll Op!lmH Q :; :: = > ... r-..~~ N~~ ~ ~~ .~O> u..ZO <~ ~~ ~~ ~...~ Cf)E-t ~~ Cf)~ E C!l c: o ~ I <II ~ ~ <II U UJ <~ ~ ~ -0 ] 't1 6 ~ III Cl tl ~ T errabay Project City of South San Francisco August 29. 1996 Revised Draft SEIR IV.C. Transportation Page 155 r Resultant AM peak hour operation: LOS D with a .80 V/C ratio (with no increased TOM r measures). r The project's contribution to the AM peak hour Impact could not be reduced to a r level of Insignificance. As explained previously, the project would not contribute to but r rather would reduce Base Case unacceptable PM peak hour operation at this intersection r due to diversion of traffic to the new southbound hook on-ramp to be installed as part of r project Phase III. However, in the AM peak hour, intersection level of service at this r intersection after mitigation would be LOS E (a .94 V/C ratio) with the project--Le., a r significant impact. r (Supplemental Impacts T-11 and T-13) fJayshore Boulevard/US 101 southbound r ramps/project commercial access: r With the southbound to eastbound flyover off-ramp, also add the lanes listed below to the r base geometrics presented in Figure 26. with a fair-share cost contribution from each r project phase: r . Add a second eastbound through lane; and r . Adding a second southbound left turn lane and a second northbound left turn lane on the r Bayshore Boulevard approaches is also recommended to reduce vehicle storage queue r lengths due to heavy left turn volumes in both directions. r In addition. provide a channelized median opening at the north driveway to the project r commercial areas along Bayshore Boulevard to allow left-turn inbound movements (in r addition to proposed right-turn in and outbound movements). r Resultant peak hour operation: LOS 0 in the AM peak hour; LOS D in the PM peak r hour. r (Supplemental Impact T-14) Hillside Boulevard/Chestnut Avenue. Implement mitigation recommended for Supplemental Impact T-1. r (3) Freeway Link Improvements (a) Year 2000: No significant impacts identified; no mitigation required. (b) Year 2010: r (Supplemental Impact T-15) Year 2010 - Phases I, /I and III. Caltrans does not plan to add additional travel lanes along the segment of US 101 between the Oyster Point Boulevard interchange and South Airport Boulevard interchange undercrossing by the year 2010. WP511548\FSEIRI/V-C-REV.548 T errabay Project City of South San Francisco August 29. 1996 Revised Draft SEIR IV.C. Transportation Page 156 r Projected unacceptable commute peak period operational impacts would warrant continued r voluntary implementation of a combination of transportation demand management (TDM) (see r mitigation (5) Transportation System Management Measures, below) to reduce peak r automobile use. Such measures include incentives to car/vanpool, increased transit availability, provision of flex time working hours for employees, expansion of employee r telecommuting, etc. The project Phase III commercial area would be responsible for the r majority of the project-related impacts to US 101. r The city shall continue to cooperate with MTSMA in its efforts to encourage and foster r voluntary TDM measures in the East-of-101 and other employment intensive development r areas in order to reduce commute peak hour travel on the local freeway network. r This TDM program would have the potential to reduce traffic volumes by at least 12 percent r (see Appendix C). Nevertheless, even with the 12 percent reduction in peak period auto use, r it is extremely unlikely that this measure would reduce project related freeway link impacts to r a level of insignificance; Le., this impact would be considered a significant unavoidable r impact. (4) Freeway Ramp Improvements (a) Year 2000: No significant impacts identified; no mitigation required. (b) Year 2010: r (Supplemental Impact T-16) Year 2010 ~ Phases I, /I and III: US 101 Southbound off-ramp to Bayshore Boulevard. Each phase of the project should provide a fair share contribution towards recommended Base Case improvements. This would reduce impacts at this location to a less than significant level. r (Supplemental Impact T-17) Year 2010 - Phases I, /I and III: US 101 Northbound off-ramp to Dubuque Avenue. Each phase of the project should provide a fair share contribution towards recommended Base Case improvements. This would reduce impacts at this location to a less than significant level. r (Supplemental Impact T-18) Year 2010 - Phases I, /I and III: US 101 Northbound on-ramp r from Oyster Point Boulevard. The TSM measure described above under mitigation sections r a(1) and b(1), Le., and the resultant 12 percent additional peak period reduction in automobile r use, will reduce this impact to less than significant levels. No additional mitigation would be r necessary. Resultant PM peak hour operation: Under capacity. r (5) Transportation System ManaQement Measures. Year 2010 Base Case mitigation needs r without the project identified above represent the maximum practical mitigations at those WP51 \548\FSEIRI/V-C-RE V. 548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR IV.C. Transportation Page 157 r intersections for which significant project impacts have been identified. Implementation of the r year 2010 Base Case mitigations recommended above would also mitigate the proiect impacts r to less-than-significant levels, with three exceptions: Supplemental Impacts T-9, T-10 and T- r 15. No feasible additional geometric mitigations beyond the year 2010 Base Case r mitigation needs have been Identified for these two Impacts. Therefore, implement the r voluntary TSM program described in section 4.a(5) herein-osee pages 146 and 149, for Base r Case Mitigation Needs Without Project and include project phases II, III, and IV in the r program. r General Mitigation Result: a 12 percent reduction in anticipated peak period trip generation r for Base Case plus Project employment-intensive uses (see Appendix C). r Associated Specific Results: mitigation of Supplemental Impacts T-9 and T-10 to a less than r significant level (see Table 20). Project impact on the US 101 freeway segment north of r Sierra Point and south of Oyster Point would remain unavoidable (projected to operate at LOS r F with or without project, even with successful continuation of TSM). r (6) Co/ma Intersection Improvements (a) Year 2000: No significant impacts identified; no mitigation required. (b) Year 2010: r (Supplemental Impact T-19) Year 2010 - Phases I, II and 11/: Hillside Boulevard/Serramonte Boulevard. Require that project phases II and/or III provide a reasonable fair share contribution towards improvements needed at this intersection by 2010 if it is operating unacceptably during the peak hour. The contribution should be in proportion to the volume of project traffic passing through the intersection in relation to the total traffic volume. In addition, any major new development projects in the town of Colma located along or in close proximity to Hillside Boulevard should be required to provide their fair share contribution towards needed improvements along Hillside Boulevard in South San Francisco. WP51 \548\FSEIRI/V-C-REV.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SErR IV.C. Transportation Page 158 WPS11548IFSEIRIIV-C-REV.S48 T errabay Project City of South San Francisco August 29, 1996 WP511548IFSEIRIAPP-C.548 APPENDIX C TDM-BASED 120/0 VEHICULAR TRIP RATE REDUCTION ASSUMPTIONS Revised Draft SEIR Appendix C T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEtR Appendix C WP51 \548IFSEIRIAPP-C.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR Appendix C The following peak hour commute mode and associated vehicular trip reduction rate assumptions have been applied in estimating the trip generation characteristics of the base case (cumulative) and base case plus project development scenarios. EIR Peak Hour Commute Mode Assumptions % of Mode Ttl. Trips Rationale Carpool 8.5 Data provided by the Multi-City TSM Agency in San Mateo County from an April 1996 telephone survey of commuters by Rides for Bay Area Commuters, Inc., (RIDES) indicate that the MTSMA region has been experiencing an approx. 17.0% carpooling rate (see Table C-1 in this appendix). Assuming that even without BAAQMD Rule 13, a similar rate would continue to be experienced in the project vicinity of So. San Francisco (prelim. Multi-City TSM Agency surveys indicate that this will be true), and assuming 2 persons per carpool, an approx. 8.5% reduction in vehicular trips has been assumed. Transit 7.0 RIDES 1996 telephone surveys indicate that approx. 9.3% of commute trips countywide in 1996 used transit (bus, BART, and Caltrain) (see Table C-1 in this appendix). Based on East-of-101 studies and surveys by the City, Brisbane surveys, and anticipated transit service provisions in the East-of-101 area and project vicinity, a 7.0% trip reduction figure has been assumed for bus, BART, and CalTrain use in the study area. Bicycle 2.0 RIDES 1996 telephone surveys indicate that the county as a whole has been experiencing a 2.3 percent bicycle use rate (see Table C-1 in this appendix). Bicycling conditions in the project and East-of-101 areas will be somewhat constrained. Motorcycle 0.5 Based on RIDES 1996 telephone surveys on countywide commute modes (see Table C-1 in this appendix). Vanpool Based on RIDES 1996 telephone surveys on countywide commute modes (see Table C-1 in this appendix). TOTAL 18.0 WP511548IFSEIRIAPP-C.548 Terrabay Project City of South San Francisco August 29. 1996 Revised Draft SEIR Appendix C Trip Reduction Implications The peak-trip generation rates used in the Terrabav Soecific Plan and Development Aareement Extension SEIR traffic analysis for commercial/employment uses are based on ITE case studies, and therefore inherently include some trip reduction, perhaps 5 to 7 percent, for conventional TDM measures (carpooling, transit, bicycle, and vanpool). Therefore, it is assumed that the trip generation figures used in the analysis already include an approximately 6 percent reduction due to conventional TSM measures. Based on this assumption, and the 18.0% alternative commute mode figure above, an additional 12 percent peak period trip reduction rate has been assumed as possible with the additional TOM measures described. WP51 \548\FSEIRIAPP-C.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEtR Appendix C Table C-1 COMMUTE MODES--APRIL 1996 TELEPHONE SURVEY OF COMMUTERS Mode Bav Area MTSMA Drive alone 63.8% 64.0% Carpool 16.3 17.0 Bus 6.6 5.8 BART 5.4 7.1 Walk 2.8 1.0 Bicycle 1.6 0.7 Other* 0.9 1.0 Work at home 0.7 0.2 CalTrain 0.6 2.2 Motorcycle 0.5 0.2 Vanpool 0.3 0.5 Ferry 0.3 Light rail 0.2 0.2 Total 100% 100% County of San Mateo San Francisco 65.8% 18.3 2.5 3.5 2.3 2.3 1.3 0.5 3.3 0.5 35.8% 9.0 30.3 8.5 8.8 2.8 0.5 0.8 0.3 1.5 100% 2.0 100% SOURCE: RIDES for Bay Area Commuters, Inc., Commuter Profile '96, July, 1996, MTSMA Region Supplement; page 2. * Other in this instance may refer to being dropped off, taking a taxicab to work, or even, in some instances, flying an airplane to work. The commute modes are clustered in Table 1 a. Driving alone includes motorcycling. Carpooling includes vanpooling. Transit includes buses, BART, CalTrain, and light rail. Other includes walking, bicycling, and working at home. Table C-1a COMMUTE MODE CLUSTERS--APRIL 1996 TELEPHONE SURVEY OF COMMUTERS County of Mode Bav Area MTSMA San Mateo San Francisco Drive alone 64.3% 64.2% 66.3% 37.3% Carpool 16.7 17.5 18.3 9.0 Transit 13.0 15.3 9.3 41.0 Other 6.0 2.9 6.3 12.8 SOURCE: RIDES for Bay Area Commuters, Inc., Commuter Profile '96, July, 1996, MTSMA Region Supplement; page 2. The Commute Profile data is residence-based. According to the 1990 census, in the Bay Area, only about three-quarters of the working population live and work in the same county. The live/work ratio is 56.2% in San Mateo County, one of the lowest in the region. MTSMA region commuters are likely to be traveling out of the county. WP51 \548\FSEIR\APP-C.548 T errabay Project City of South San Francisco August 29, 1996 Revised Draft SEIR Appendix C The incidence of carpooling in the MTSMA region is higher than the Bay Area average, but slightly lower than the rate for the county as a whole. WP5115481FSEIRIAPP-C.548