The 2.2-mile San Gabriel Trench grade separation project includes the lowering of a 1.4-mile section of Union Pacific railroad track in a trench through the City of San Gabriel, allowing vehicles and pedestrians to pass over the tracks. Group Delta provided environmental services, installation of tiltmeters and crack gauges, soils sampling and testing, engineering support and consulting services.

Location: Los Angeles, California
Client: The Walsh Group / City of San Gabriel (Owner)