C+S September 2020 Vol. 6 Issue 9 (web)

Los Angeles Regional Connector Will Open Up Options for Commuters By Richard Reitz

Commuting through Los Angeles is notoriously frustrating, but it is on the verge of getting a little easier with one of the city’s most ambitious transportation projects entering the home stretch. For the past 12 years, Los Angeles County Metropolitan Transporta- tion Authority (Metro) has been planning and building its Regional Connector, a 1.9-mile twin-tunnel underground rail system that will link three light rail transit lines and the heavy rail subway. Targeted for completion in 2022, having stayed on schedule through- out the COVID-19 pandemic, this new Metro Rail extension will offer a transportation option that for many commuters will provide a viable alternative to congested roadways. It will also provide significant environmental benefits and economic development throughout Los Angeles County. For many commuters, it means a one-seat ride for travel that was previously not possible. Present-day Metro Gold Line passengers, for example, will be able to travel directly from Azusa to Long Beach, or from East Los Angeles to Santa Monica, without transferring lines. “By reducing the need for transfer trains when traveling through and to downtown Los Angeles, the new connector is expected to save commuters up to 20 minutes of travel time on every trip,” said Bill Hansmire, WSP USA underground design manager. “This connection is going to open the door for many people to consider public transpor- tation where this option was previously not practical or possible.” WSP, in a joint venture with AECOM as the Connector Partnership, is providing transportation planning, rail design, and rail planning for the Regional Connector. Since joining the project to provide conceptual engineering and the draft environmental impact statement (DEIS) in 2008, the firm’s responsibilities have included tunnel and geotechnical engineering, tunnel ventilation, rail systems, travel forecasting, opera- tional analysis, and mechanical, plumbing and electrical engineering. WSP is working on behalf of Metro with Regional Connector Con- structors, the joint venture of Skanska and Traylor Brothers, Inc. that is contracted by Metro to design and build the project. Mott MacDonald is serving as the final designer for the project. It is estimated that the $1.81 billion Regional Connector will serve 88,000 riders every day, including 17,000 new riders. The project improves access to both local and regional destinations by providing continuous thru service between these lines and providing connectors

Tunnel under construction. Photo: LA METRO

to other rail lines via the 7th St/Metro Center Station, allowing pas- sengers to bypass Union Station and transfer to the A (Blue), E (Expo), B (Red) and D (Purple) Lines. ‘Angeli’ The success of the Regional Connector project centered around the construction of two parallel 1.1-mile-long tunnels using a state-of-the- art tunnel boring machine (TBM) nicknamed “Angeli” and manufac- tured in Germany by Herrenknecht AG. Angeli weighed about 1,000 tons, was 400 feet long and nearly 22 feet in diameter. It advanced about 50 to 70 feet per day on average and mined 10,900 feet between the two tunnels, excavating over four million cubic feet, or 240,000 tons, of earth. Digging for the first half of the 1.1-mile tunnel concluded in July 2017, when Angeli broke through to a reception pit at 4th and South Flower streets in the city’s downtown. Angeli was then transported to the origi- nal starting point at 1st Street and Alameda in Little Tokyo to continue digging the parallel tunnel, which was completed in January 2018. Angeli overcame several challenges, including a culturally sensitive building complex that was protected by performing permeation and

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