In fall 2017, Silicon Valley transportation and community leaders, businesses, and residents will celebrate their long-awaited dream of bringing regional transit service to the South Bay area when the first phase of the BART Silicon Valley Extension — also known as the Berryessa Extension — opens to the public. The 10-mile, two-station Berryessa Extension will begin south of the future Warm Springs station in Fremont, Calif., proceed through Milpitas, and end in the Berryessa area of north San Jose.
The $2.3 billion project includes two stations: Milpitas Station, located at the intersection of Montague Expressway and Capitol Avenue; and Berryessa Station, located between Berryessa and Mabury roads adjacent to the San Jose Flea Market. The second phase of the extension, anticipated to begin in 2019 once funding is secured, will further extend the BART system from the future phase one terminus for approximately six miles, ending in Santa Clara near the Caltrain station. Four stations are proposed for the second phase.
A decade of planning
The BART Silicon Valley Extension project represents the culmination of a decade-long effort by South Bay community and transportation leaders. In November 2000, Santa Clara County voters approved a 30-year, half-cent sales tax that would provide funding for 14 transit projects, including the concept to extend BART to the cities of Milpitas, San Jose, and Santa Clara.
The next year, a major Investment Study/Alternatives Analysis was completed, which confirmed that the proposed BART Extension to Milpitas, San Jose, and Santa Clara was the best transit alternative for the congested I-880/I-680 corridors. Following the study, Santa Clara Valley Transportation Authority (VTA) and BART, in November 2001, entered into a comprehensive agreement for the 16-mile BART Silicon Valley Extension. Under the terms of the agreement, VTA is overseeing construction and BART will operate the extension upon completion.
As VTA ramped up the engineering activities needed for the extension, in 2005 the agency decided to build the project in two phases to secure federal funding. In November 2008, Santa Clara voters approved an additional one-eighth-cent sales tax for operation and maintenance of the planned extension. In March 2012, VTA entered into a $900 million Full Funding Grant Agreement with the Federal Transit Administration. In April 2012, after a decade of planning, engineering, and securing funding, construction started on the Berryessa Extension.
To successfully implement the project, VTA awarded a $772 million design-build contract to the Skanska, Shimmick, and Herzog (SSH) joint venture. This contract included design and construction of the line, track, systems, and stations for the Berryessa Extension. Lockwood, Andrews & Newnam, Inc. (LAN), a planning, engineering, and program management firm headquartered in Houston, and T.Y. Lin International Group were selected as designers under the SSH joint venture contract. VBN Architects and FMG Architects performed preliminary design for the Milpitas and Beryessa Stations, respectively, and Anil Verma Associates, Inc. provided final design services for the two stations.
While the Berryessa Extension incorporates many features that will enable commuters to have an enjoyable travel experience, the highlight of the project is its two stations. The future Milpitas Station, located near the Great Mall in Milpitas, is the center of the city’s Transit Area Specific plan and will serve as BART’s gateway to Silicon Valley. Situated on a 27-acre campus, the station consists of a grade-level concourse with below-grade split level boarding platforms. A 260-foot pedestrian over-crossing bridge will provide a seamless connection to the existing VTA Montague Light Rail Station. The station’s design reflects Milpitas’s rich industrial history.
The Berryessa Station consists of a ground-level concourse with aerial boarding center platform. The station’s curved canopy structure, minimal use of solid walls, open mesh panels, and clear sight lines evoke San Jose’s agricultural past and natural habitat.
Both station campuses include stepped level, four-bay parking garages that will accommodate more than 1,100 parking spaces. The station campuses also feature bus transit centers to connect with VTA services, private shuttle and passenger drop-off/pick-up areas, and convenient bicycle and pedestrian connections and storage spaces.
The strategic location of the stations also will have a huge economic impact. At the Milpitas station, tens of thousands of commuters will be able to quickly access nearby destinations such as the Great Mall of the Bay Area or connect to VTA’s light rail/bus system to reach major employers such as Google, eBay, and Cisco Systems in the high-tech, job-rich northwestern areas of Santa Clara County, as well as attend events at the state-of the-art Levi’s stadium, home of the San Francisco 49’ers. Directly adjacent to the Berryessa Station on its west side is the San Jose Flea Market, which attracts more than 4 million visitors a year. Already, transit-oriented development opportunities have exploded around the stations with increased demand for thousands of housing units and nearly 2 million square feet of retail and office space currently under planning and development.
Building a commuter rail line in a high-density corridor required tackling several challenges. Chief among them was coordinating with as many as 13 major utility owners in the Berryessa Extension corridor. Some utilities such as MCI and Chevron paralleled the corridor for all 10 miles and were located within a 10-foot easement in the VTA/BART right-of-way, further complicating the challenge. As such, a major component of the project involved working closely with various utilities to ensure that the various parties’ design plans weren’t in conflict. The team also implemented a utility production program that included daily signoffs before excavation.
The project team also came up with alternative technical design concepts to avoid utility relocations in other areas. For example, the Sierra/Lundy intersection in the City of San Jose is a crossing of two major streets. Initial design plans called for a shallow guideway trench that disrupted numerous utility lines and required construction of huge siphons for stormwater and wastewater. The design team developed a scheme whereby the track alignment could be lowered at the intersection and placed in a cut-and-cover tunnel. This solution dramatically reduced disruption of the intersection during construction and eliminated the need for numerous utility relocations and also eliminated the need for the siphons.
Another challenge involved a section of Union Pacific Railroad (UPRR) track that paralleled the Berryessa Extension corridor. To maintain rail service to UPRR while a new overpass and industrial lead spur was being built over the BART tracks, the project team constructed a shoofly. The team also implemented a railroad intrusion detection laser system that would alert operations personnel in the event of a right-of-way breach.
Approximately two years into the project, a remapping of the flood plain near the Milpitas Transit Center created additional challenges for the project team. To deal with this challenge, the team built an 800-foot-long trench section and installed 306 water-balancing pipes both underneath and along the sidewalls of the trench. This creative solution enabled the team to continue construction on the project and also comply with the stormwater requirements.
Despite these challenges, the Berryessa Extension is well on track for a fall 2017 opening, several months ahead of schedule. Once the second phase is also completed, the BART Silicon Valley Extension will provide the final link needed to complete the current 20-mile gap in the regional rail system around San Francisco Bay and tie together the region’s three major metropolitan centers — San Jose, San Francisco, and Oakland — further cementing its status as one of the top mass transit systems in the country.
Timothy J. Schmidt is a senior associate and director – Northern California at Lockwood, Andrews & Newnam, Inc. (LAN; lan-inc.com), a planning, engineering, and program management firm. He can be contacted at email@example.com. Bernice Alaniz is the director of communications and public affairs at the Santa Clara Valley Transportation Authority (vta.org). She can be contacted at firstname.lastname@example.org.