Metro L Line

formerly Edward R. Roybal Metro Gold Line
Eastside Extension

The Project.

The Metro Gold Line Eastside Extension (MGLEE) is located in eastern Los Angeles and the East Los Angeles district of unincorporated Los Angeles County. From Union Station, the alignment runs through eastern downtown Los Angeles, Boyle Heights, and East Los Angeles, terminating at the intersection of Pomona and Atlantic boulevards. The 6-mile long alignment consists of approximately 4 miles of double-track at-grade trackwork and nearly 2 miles of underground guideway. Elements along the alignment includes six at-grade stations, two underground stations, an upgrade and seismic retrofit of the overpass over I-710, retaining structures, street improvements and trackwork.

Owner:

Los Angeles County Metropolitan Transportation Authority

Location:

Los Angeles, CA

Services:

  • Geotechnical
  • Geotechnical Testing
  • Design-Build Delivery

Project Fact:

Named after Boyle Heights resident and long-time Los Angeles political activist, City Councilman and US Congressman, the Edward R. Roybal.

The Leighton Solution.

As the design-build geotechnical engineer for the project, Leighton provided cost-effective, yet technically and environmentally acceptable geotechnical design approaches and geotechnical engineering support to the design team. Since the project was on a very aggressive schedule, fast turn-around and prompt response was essential. As part of the design-build team, Leighton also worked very closely with different design groups and agencies such as the structural and civil engineers, the City and County of Los Angeles, and Caltrans.

Leighton’s involvement in the project consisted of performing field exploration and laboratory testing, and providing geotechnical design and support for the project team. During the field exploration, members of our technical staff logged and obtained soil samples from the borings. Over 50 feet of excavation was performed during construction of the underground stations. Issues such as dewatering, potential impact to nearby structures due to excavation, heaving and settlement of the soil during excavation, and temporary support and shoring were addressed. Deep foundation recommendations for the freeway overpass upgrade were developed according to Caltrans design standards. All designs meet the Metro Design Criteria and the requirements of Caltrans, Los Angeles City Bureau of Engineering and Los Angeles County Public Works Department.