Over nearly 20 years, WSP USA, as the lead member of the Eastside LRT Partners joint venture, provided planning, design and construction engineering services to the Los Angeles County Metropolitan Transportation Authority (Metro) for the Eastside Extension, including six at-grade stations, two underground stations and a 1.7-mile midsection tunnel through Boyle Heights.
We brought several innovations to the project, including recommending the use of pressurized-face tunnel boring machines that resulted in virtually no ground settlement during construction, minimal disruption to the community, and no impact to existing infrastructure or buildings. Another WSP-proposed innovation was the use of double-gasket precast concrete segmental liners to contain gas and water seepage, which saved time and expense. The Eastside Extension project was completed ahead of schedule and within budget in November 2009.