When the City of L.A. Department of Water and Power needed to construct a new water reservoir in the Hollywood Hills it was confronted with a dilemma. Although mandated by federal law to provide the covered reservoir, local opposition prevented the covering of the existing scenic Hollywood Reservoir. Additionally it was early determined that above grade tanks would be equally unsightly.
Cefali & Associates engineered a mostly tied back soldier pile system to support the 50 ft. depth required for the 200 ft. diameter tanks. A portion of the site required the construction of a tied back concrete slurry wall to seal off the adjacent Hollywood Reservoir. This project proved to be especially difficult due to its combination of soldier piles and slurry walls and the need to provide tunnel drifts at the excavation face for the construction of two water line tunnels exiting the tanks.
Contractor: Condon Johnson & Associate
Geotechnical Engineer: URS