Marine Construction on Loch Lomond Inlet/Outlet Replacement Project at Newell Creek Dam, Ben Lomond, CA-PPT Presentation

PPT Presentation

Pdf Summary

The City of Santa Cruz’s Newell Creek Dam Inlet/Outlet Replacement Project was carried out by prime contractor Obayashi Corporation and drilling subcontractor Drill Tech Drilling & Shoring, Inc. Marine work ran from July 2020 to March 2022.<br /><br />The complex reservoir project required extensive site mobilization, including access-road and trestle construction, shoreline grading, barge assembly, and installation of approximately 1,550 feet of turbidity curtain. The curtain extended about 145 feet underwater and was inspected and maintained with a remotely operated vehicle. A marine launchway and casting sled enabled the team to cast and launch heavy precast inlet foundations, or “donuts,” on site.<br /><br />Approximately 25,000 cubic yards of rock were dredged to depths of around 115 feet. Three precast foundations were installed at the upper, middle, and lower inlets, anchored to bedrock and secured with tie-backs. Crews then drilled three six-foot-diameter shafts from the reservoir bottom, installed permanent casings and standpipes, and fitted inlet structures and debris walls. A roughly 600-foot, 20-inch-diameter air vent line was also installed along the dam slope, supported by casing piles.<br /><br />The project team reported completing the work on schedule and within budget, with no lost-time injuries. Despite the COVID-19 pandemic, work proceeded without stoppage, supported by a collaborative, solutions-focused partnership among the project participants.

Keywords

Newell Creek Dam

Santa Cruz

inlet outlet replacement

reservoir project

Obayashi Corporation

Drill Tech Drilling & Shoring

marine construction

turbidity curtain

precast foundations

drilling and dredging