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FACT SHEET: BART Silicon Valley

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FACT SHEET: BART Silicon Valley Twin-Bore Single-Bore Running Tunnel Running Tunnel Utilities Utilities Up to ~60' FACT SHEET: VTA’s BART Silicon Valley Phase II Extension Project FACTTunneling MethodologySHEET: BART Silicon Valley VTA’sVTA’s BART BART Silicon Silicon Valley Phase Valley II Project Phase is a six-mile, ll Extension four-stationUp extensionProject to ~75' that will bring BART train service from Berryessa/North San José through downtown San José to the City of Santa Clara. The Phase II Project will include an approximately five-mile tunnel, two mid-tunnel ventilation facilities, a maintenance facility and storage yard, three VTA’sunderground BART Siliconstations (AlumValley Rock/28th Program Street, Overview Downtown San José, Diridon), and one ground-level station (Santa VTAClara). is extending The subway the tunnelBART regionalwill be in heavy one large rail system diameter to Milpitas,tunnel. San Jose, and Santa Clara. The 16-mile extension, called the BART Silicon Valley Program, will extend the BART system south of BART’s future Warm Springs/SouthSingle-Bore Fremont Tunnel Station in Fremont to Milpitas, San Jose, and Santa Clara. When completed, this fully grade-separatedThe tunnel will be project constructed is planned as a tosingle, include large six diameter stations andtunnel. a new The maintenance and storage facility in Santa Clara.approximately VTA’s BART 45 footSilicon tunnel Valley will Program contain istwo being independent delivered trackways,in two phases. one Thefor Berryessa Extension Project (Phaseeach direction I) is under of constructiontravel. Passenger and scheduled platforms willto open be located in 2018, within with thestations tunnel, in Milpitas and the Berryessa areaconnected of San toJose. station The entrancesPhase II Extension via underground Project (Phasepassageways. ll) will include Depending a 5-mile-long on subway tunnel through downtownthe station, San platforms Jose and will will be extendapproximately the BART 66 systemand 85 fromfeet belowthe future ground. Phase I terminus for approximately six miles to the City of Santa Clara. Four stations are proposed for Phase II: Alum Rock/28th Street, Downtown SanWithin Jose, the Diridon, tunnel, thereand Santa will be Clara. emergency egress points spaced every 300 to 600 • Mined cross-passage for emergencyfeet that will allow passengers to reach non-affected areas during an emergency Phasesituation. II ScheduleThe tunnel will be excavated with a Tunnel Boring Machine (TBM) at an evacuation between tunnels Publicaverage Review depth of of Draft 60 feet. Environmental At stations, Documentsoft ground (SEIS/SEIR)..................... mining techniques will be December used 2016 through March 2017 to excavate the underground connections between the tunnel (which contain the Preparation of Final SEIS/SEIR .................................................................... March 2017 through January 2018 boarding platforms) and the off-street station concourses. Release of Final SEIS/SEIR........................................................................... February 2018 VTAHow Board does Approves a Tunnel Project......................................................................... Boring Machine (TBM) Operate? •April Sliding 2018 re door for emergency evacuation FTAA tunnel Approves boring Project.................................................................................... machine (TBM) is a large drill that excavates and installs the June betweeninitial 2018 tunnel lining tracks that supports when the side-by-side tunnel needed for the train to travel underground. The front section of the TBM (the cutter head, seen in photo Construction Begins...................................................................................... 2018 below on the left) chips, grinds, and removes the dirt. Passenger Service......................................................................................... 2026 • Within the large hole created, precast concrete segments will be installed to form rings to support the tunnel. The precast rings will be sealed to prevent water and mud from seeping into the tunnel. • Soil will be removed via launch portals and either hauled away or reused for the project. • The TBM will be powered by a temporary electric substation and will enter and exit the tunnel through either of Track Con gurationsthe portals.in Running Tunnel VTA’s BART Silicon Valley• Once Phase the TBM has completedII Extension digging the tunnel, theProject track and facilities can be installed. The specific type of machine and path of travel will be determined as the project progresses. March 2018 Continued on reverse side Istanbul Straight Road Project VTA BART Ext Phase ll 021418 Continued on the reverse side HowFACT will the communitySHEET be impacted: BART during construction?Silicon Valley TheVTA’s single-bore BART tunneling Silicon methodology Valley reduces Phase construction ll Extension impacts overProject traditional methods by conducting most excavation without disrupting the street. However, a major construction project like the Phase II Project will have impacts to the community. For example, during construction, including utility relocations, there will be sidewalk and laneVTA’s closures BART as Silicon well as containedValley Program impacts Overview at the station entrances, portals and ventilation structures. VTA will continue to work with the cities of San José and Santa Clara, the construction contractors, the public, and local residents and businessesVTA is extending to minimize the BART impacts regional to the heavy extent rail possible. system Majorto Milpitas, project San construction Jose, and Santa is expected Clara. Theto start 16-mile in 2020. extension, called the BART Silicon Valley Program, will extend the BART system south of BART’s future Warm Springs/South Fremont Station in Fremont to Milpitas, San Jose, and Santa Clara. When completed, this fully grade-separated project is planned to include six stations and a new maintenance and storage facility in Santa Clara. VTA’s101 BART Silicon Valley Program is being delivered in two phases. The Berryessa Extension Project (Phase I) is under construction and scheduled880 to open in 2018, with stations in Milpitas and the Berryessa680 area of San Jose. The Phase II Extension Project (Phase ll) will includeBERRYESSA/ a 5-mile-long subway tunnel through downtown San Jose and will extend the BART system from theNORTH future SAN Phase JOSÉ I terminus for approximately six miles to the City of Santa Clara. Four stations are proposed for PhaseSTATION II: Alum Rock/28th Street, Downtown San Jose, Diridon, and Santa Clara. Mineta N 1st St San Jose International Airport Phase II Schedule 87 East Portal (Typical Portal) 101 Public Review of Draft Environmental Document (SEIS/SEIR)..................... December 2016 through March 2017 PreparationSANTA CLARA of Final SEIS/SEIR .................................................................... March 2017 throughMcKee Rd January 2018 STATION Taylor Rd W Hedding St Release of FinalNewhall SEIS/SEIR........................................................................... February 2018 Maintenance VTA Board ApprovesFacility Project.........................................................................13th St April 2018 ALUM ROCK/ 28TH STREET FTA Approves Project.................................................................................... June19th St 2018 Coleman Ave STATION Construction Begins...................................................................................... 2018 24th St 680 Passenger Service.........................................................................................Typical Underground Station 2026E Santa Clara St 13th Street Ventilation Facility DOWNTOWN West Portal (Typical Portal) W Santa Clara St DIRIDON STATION SAN JOSÉ STATION 10th 11thSt St Stockton Avenue Market St 4th St Ventilation Facility 1st St 87 880 LEGEND Phase I Alignment N Phase II Ground-Level Alignment 280 Phase II Single-Bore Tunnel Alignment NOT TO SCALE VTA’s BART Silicon Valley Phase II Extension Project Draft Recommendations July 2018 Continued on reverse side VTA BART Ext Phase ll 021418.
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