Overview
To assist the prime contractor with fender installation on the Bay Bridge’s Eastern Span Tower 1, Ballard provided a commercial diving crew and equipment to remove marine growth from all forty-six locations of the submerged vertical concrete face, top of corbel, and rebar hoops.

Scope of Work
Ballard used specialized underwater cleaning equipment to remove marine growth, leaving the epoxy coating intact on the rebar. Divers then assisted California Department of Transportation (Caltrans) surveyors to shoot on top of the corbel and in each rebar hoop. To reduce the environmental impact of the excess marine growth and blast media, Ballard’s dive crew dredged materials off the containment bottom.

Innovative Solutions
This work took place in an environmentally sensitive area. Ballard was responsible for the containment of debris and reduction of impacts to turbidity levels from cleaning and fender installation. To do this, Ballard procured and installed an impermeable floating containment curtain for the cleaning. The curtain was secured to the sides of the area to be cleaned and the bottom was secured to the fender underneath the area.

Results
These techniques proved integral to the preservation of the surrounding environment of the bridge. The maintenance of the ecosystem under and around the bridge was Ballard’s number one objective. Via these specialized methods, the jobsite was left even cleaner, stronger, and more environmentally friendly upon completion of work.