Big Tujunga Dam Seismic Rehabilitation and Spillway Modification
- OWNER: Los Angeles County Flood Control District
- CONTRACT VALUE: $94,765,000
- NTP / START: April 2008
- COMPLETION: November 2011
- WORK DESCRIPTION:
The Big Tujunga Dam is located at the base of the San Gabriel Mountains and was constructed in the early 1930’s to control floods and to conserve water. While it was built with a storage capacity of 5,960 acre-feet of water, the California Division of Safety of Dams (DSOD) imposed a seismic restriction on the dam in 2004 that limited the long-term storage to 1,484 acre-feet.
The project improved the safety of the dam by cleaning the foundation, placing mass concrete, modifying the spillway, removing and replacing the dam crest and appurtenant structures, stabilizing the canyon walls with consolidation drilling, grouting, and rock bolts, and establishing a new dam control system. The original storage capacity was restored.
The specifications required the concrete to be placed at 50 degrees and kept below 55 degrees for the duration of curing. To accomplish this, chilled water was used and ice added to the batches when temperatures were high (the dam is near Los Angeles and concrete was placed throughout the summer). Cooling tubes run through the blocks of concrete to circulate 40 degree water through them, and the tubes were grouted after the blocks were cured.
SCCI self-performed the Electrical scope of work.
News & Awards
- Joe Pacheco recognized for Individual Safety Effort of a Superintendent by AGC of CA
- ENR 2011 Best Civil Works / Infrastructure Project In California
- Shimmick Wins AGC 2011 Award for Innovation
- American Public Works Association Honors Big Tujunga Project for 2012
- The United States Society on Dams 2012 Award of Excellence
- National Rehabilitation Project of the Year 2011
- SCCI awarded United Contractors R.E.A.L safety award in 500,000+ Man hour category
- SCCI ranked in top 200 Environmental Firms for first time at #63
- SCCI ranked #1 in Water Supply in California in new ENR rankings