Silicon Valley Berryessa Extension Design-Build Project – Bay Area Rapid Transit (BART)
Fremont, Milpitas, San Jose, California
The VTA Silicon Valley Berryessa Extension consists of the design and construction of a 10-mile extension of the Bay Area Rapid Transit (BART) system into Santa Clara County. The extension will connect to the track south of the BART Warm Springs Station and proceed in the former Union Pacific Railroad corridor through Milpitas to the Berryessa District of San Jose. The alignment is a combination of at-grade, open-cut and aerial guideway configurations, and includes a retained-cut passenger station in Milpitas (Milpitas Station) and an above-ground passenger terminus station in San Jose (Berryessa Station).
LAN is currently serving as design manager and lead designer for the Berryessa Extension providing design services including civil engineering, structural engineering, drainage, hydraulics and hydrology, utilities, traffic planning and maintenance of traffic, geotechnical engineering, environmental engineering, trackwork, systems, and architecture/engineering for two large stations.
LAN has developed more than 70 alternative technical design concepts for the project–more than 20 of which have been implemented after owner approval. For example, the Sierra/Lundy intersection in San Jose crosses two major streets. The initial design showed a shallow guideway trench that disrupted numerous utility lines and required the construction of huge siphons for storm water and wastewater. LAN developed a scheme whereby the track alignment could be lowered at the intersection and placed in cut-and-cover tunnel. This design 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.
At a glance
$772 million design-build project cost
$2.3 billion estimated contract cost
LAN is lead designer responsible for a 10-mile portion of the 16-mile extension
A major stakeholder, Union Pacific Railroad owns tracks parallel to the corridor for approximately 5.5 miles, and has a major rail yard in Milpitas
One of the design units included the construction of a shoofly to maintain rail service to Union Pacific Railroad
The 10-mile project was divided into 31 design units
Two Stations; one below grade and one aerial
LAN has developed more than 70 alternative technical design concepts for the project–more than 20 of which have been implemented after owner approval.
Funding for the project comes from local, state and federal sources
Relocated approximately 700 LF of 60-inch water transmission pipe from the aerial station footprint
Utilizing lightweight cellular concrete (LCC) backfill for mechanical stabilized earth approaches. The use of the LCC alleviated soil subsidence and a potential drawdown of bridge piles and neighboring structures. First of it’s kind for a rail corridor in the U.S.
Construction Mgmt & Inspection
Bay Area Rapid Transit (BART)