Kleinfelder - PG&E CWA #66 Alviso Pond

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PG&E CWA #66 Alviso Pond

PG&E
Alviso, CA

Project Description:

Pacific Gas and Electric Company plans to raise several existing electric power transmission line towers that cross very soft ground conditions in Alviso, CA. The original towers were constructed in the 1910s. As part of the tower modification project, the tower foundations may need to be upgraded to support the added mass of the modified towers. The existing tower footings are supported by timber piles of unknown length. According to PG&E, the existing timber piles are probably about 60 feet long.

Scope of Work

Geotechnical Consultant

Client Issues

Very soft ground conditions required specialized drilling equipment. A CME 850 drill rig mounted on a tracked carrier was used to access the site. Track width is 33 inches.
Young Bay Mud (very soft, settling clay) is 20 feet thick at the site. New piles will induce downdrag loads on the existing piles and any new deep foundations that may be added.