Construction of Interstate I-405 in Costa Mesa, California. This project, developed in Orange County for the Orange County Transportation Authority (OCTA), is one of the largest and most relevant infrastructure projects ever undertaken in the western United States.

The infrastructure, which extends from Costa Mesa to the Los Angeles County line, has been upgraded 25 km with an additional lane in each direction, as well as adding express toll lanes from State Route 73 to Interstate 605. In this project, 18 bridges were demolished and reconstructed, many with new sidewalks and bike lanes. Ramps and hundreds of retaining walls and soundproofing walls were also added.

Community benefits

The project has recycled 710,000 tonnes of concrete, which were reused for the base course of the new lanes. In addition to reduced emissions, it is estimated that travel times will be halved for nearly 400,000 daily drivers.