Pacific Coast Highway Grade Separation

Brief Overview

Appointed as the final major contract of the famous $2.4 billion Alameda Corridor project, the Pacific Coast Highway Grade Separation will eliminate traffic conflicts at two railroad crossings and the Alameda Street intersection. Yeager Skanska recently completed construction on this $30 million contract with the Alameda Corridor Transportation Authority (ACTA) ahead of schedule. The project location is in the Wilmington community of Los Angeles, just one mile from the busy ports of Los Angeles and Long Beach. Combined, these facilities handle $200 billion of cargo annually.

The most prominent feature of the work was the construction of a 503-meter long pre-cast concrete girder viaduct. The viaduct is supported on cast-in-drilled-hole piles up to three meters in diameter and 21 meters deep. The bridge has 13 spans in all with a 170 mm thick concrete deck supported on 169 pre-cast concrete girders. Additionally, a shorter connecting ramp bridge was part of the contract. The structure itself was built as a footprint to the existing highway and separates the Pacific Coast Highway traffic from the busy Alameda Corridor railroad lines and Alameda Street. The contract required the complete closure of the Pacific Coast Highway, which allowed work to progress in many areas without having public traffic as a hindrance. The contract time allowed for Yeager Skanska to construct the grade separation was clearly the most challenging aspect of the job given the tight working conditions.

Since the Pacific Coast Highway is part of the state highway system, a unique agreement was forged between the Alameda Corridor Transportation Authority and the California Department of Transportation (Caltrans). While ACTA is managing the design and construction of the project, Caltrans will eventually maintain the facility. Therefore, Caltrans oversaw the project aned provided funding for 70% of the costs. Additional involvement from the cities of Los Angeles and Long Beach and the Los Angeles Department of Water and Power created additional coordination challenges for ACTA and the Yeager Skanska team. These entities played a major role in the design of the project and were very involved with the actual construction.