SFPUC, Crystal Springs Bypass Tunnel

San Mateo, CA

This $54M project involved replacing the existing pipeline from the 1960s with a deep underground tunnel and pipeline to ensure continued delivery of drinking water after a major seismic event. The Crystal Springs Bypass Tunnel project consisted of construction of a new 4,200-foot tunnel which lies at depths of up to 160 feet underground. This pipeline is a critical link in transmitting all of the water from the Sierra and East Bay to the Peninsula. CTS provided special inspections and material testing involving nuclear field density testing, soils compaction and earth work activities, observation of field welding and nondestructive testing (ultrasonic and magnetic particle). CTS also performed steel shop inspections at K&M Welding in Atwater, CA.