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Seismic Improvement Program. Presented to: The Northern California Earthquake Hazards Workshop February 12, 2014. Water Treatment and Distribution. 1,300,000 customers 331 square-mile area ~ 4,000 miles of pipe ~ 135 pumping plants ~ 180 reservoirs/tanks ~ 125 pressure zones
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Seismic Improvement Program Presented to: The Northern California Earthquake Hazards Workshop February 12, 2014
Water Treatment and Distribution • 1,300,000 customers • 331 square-mile area • ~ 4,000 miles of pipe • ~ 135 pumping plants • ~ 180 reservoirs/tanks • ~ 125 pressure zones • Elevation: MSL-1450 ft
Predicted Damage: Seismic Evaluation Program • 63% of our customers would be out of water • Increased fire risk with 1/3 of reservoirs and 2/3 of pumping plants out of service • Claremont Tunnel would be out of service • 5,500 pipeline breaks • 4 of 6 treatment plants would be out of service
Capital Improvement Program • Package #1 ($3 million) • Improve service after smaller earthquakes • Package #2 ($84 million) • Limitedservice improvements after Hayward M-7 • Package #3 ($189 million) • Improved service after Hayward M-7 • Package #4 ($288-$360 million) • Low priority, low benefits
Main Administration Building Column Beam Column Flange Weld Beam Flange Backing Bar Fracture During Earthquake Beam-Column Connection • Structural system is a welded steel moment frame • Designed to the 1982 Uniform Building Code • Seismic Improvement Program implemented in 1994 to provide life safety for all occupied structures • Lessons learned from the 1994 Northridge Earthquake • Welded joints do not perform as designed
Piston Damper Detail Viscous Damper in Diagonal Brace State Office Building Project, San Francisco
Implementation -Tank Seismic Upgrade Shotcrete over New Anchors Prestressed Strands Shotcrete Cover
Emergency Bypass System • Manual isolation valves and by-pass manifolds • Isolate ruptured pipe and restore flow with temporary hoses
Southern Loop Pipeline • 11-miles • 30 inch to 42 inch diameter • 1,800 ft. of 9 ft. dia. tunnel • Connects Southern Part of Service Area
carrier pipe i.d: 6ft; length: 85ft 8.5ft 8.5ft Plan Configuration after design earthquake Section
Mokelumne Aqueduct No. 3 Elastomeric seismic isolation bearing install on 351 pipe supports
Dam Remediation Design Alternatives Conventional Earth Replacement Cement Deep Soil Mixing (CDSM)
Questions Timothy McGowan Associate Civil Engineer P.O. Box 24055 Oakland, CA 94623 (510) 287-1981