The North City Tunnel Connector houses four pipelines, each approximately 2,000 feet in length, in a common 19-foot diameter carrier tunnel. The project extends from pipelines previously installed and buried at the North City Water Reclamation Plant to a diversion structure west of I-805 where it connects with the Rose Canyon Trunk Sewer, a previously existing facility.
As a finished product, the pipelines carry raw wastewater to the plant and treated effluent from the plant. Likewise, reclaimed water and plant waste are carried from the plant.
The initial contract for this project included the construction of a tunnel underneath I-805 that would house an 84-inch reinforced concrete sanitary sewer line, a 54-inch ductile iron effluent line, a 36-inch ductile iron reclaimed water line, a 36-inch ductile iron waste line, and four 4-inch polyvinyl chloride (PVC) fiber optic conduits. The tunnel was excavated with a road header and initial support used ribs and lagging.
Vanir provided the Chief Resident Engineer for this project. Duties included all pre-construction activity, estimates, constructability reviews, inspection plan development, owner representation during design meetings, and handling of the bid and award process.