Seismic Improvement Program Presented to: The Northern California Earthquake Hazards Workshop...

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Seismic Improvement Program Presented to: The Northern California Earthquake Hazards Workshop February 12, 2014

Transcript of Seismic Improvement Program Presented to: The Northern California Earthquake Hazards Workshop...

Seismic Improvement Program

Presented to:

The Northern California Earthquake Hazards Workshop

February 12, 2014

Water Treatment and Distribution

1,300,000 customers331 square-mile area~ 4,000 miles of pipe~ 135 pumping plants~ 180 reservoirs/tanks~ 125 pressure zonesElevation: MSL-1450 ft

Seismic Hazards in Service Area

Pressure Zone Damage

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)– Limited service improvements after Hayward

M-7 Package #3 ($189 million)

– Improved service after Hayward M-7

Package #4 ($288-$360 million) – Low priority, low benefits

Water Treatment Plants

Column

Weld

Column Flange

Beam Flange

Backing Bar

Fracture During Earthquake

Beam-Column Connection

Structural system is a welded steel moment frameDesigned to the 1982 Uniform Building CodeSeismic Improvement Program implemented in 1994 to provide life safety for all occupied structuresLessons learned from the 1994 Northridge Earthquake• Welded joints do not perform as designed

Beam

Main Administration Building

Viscous Damper in Diagonal Brace State Office Building Project, San Francisco

Piston Damper Detail

Pumping Plants

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

Pipeline Fault Crossings and Backbone Pipe at Landslides

Supplying the West of Hills

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

Claremont Tunnel Crosses the Hayward Fault

Claremont Tunnel Before Upgrade

STA b 9+ 09 TO STA b 8+ 01

R 9 '-5"5'-0

"4'

-0"

R 8'-3"

CC

CC

C

` TUNNEL

4'-0"

# 5 @ 12"

DESIG N LINE

# 4 @ 7 1/2 "

# 5 @ 7 1/2 "

# 5 @ 12"

# 5 @ 7 1/2 "

# 5 @ 12"

# 10 @ 7 1/2 "

# 9 @ 7 1/2 "

# 5 @ 12"

# 4 @ 12"

# 4 @ 7 1/2 "

# 4 @ 12"SL

TUNNEL

4'-1 9/16 "

1'-0

" SLSIDE DRIFTS

STA b 9+ 09 TO STA b 8+ 01

R 9 '-5"5'-0

"4'

-0"

R 8'-3"

CC

CC

C

` TUNNEL

4'-0"

# 5 @ 12"

DESIG N LINE

# 4 @ 7 1/2 "

# 5 @ 7 1/2 "

# 5 @ 12"

# 5 @ 7 1/2 "

# 5 @ 12"

# 10 @ 7 1/2 "

# 9 @ 7 1/2 "

# 5 @ 12"

# 4 @ 12"

# 4 @ 7 1/2 "

# 4 @ 12"SL

TUNNEL

4'-1 9/16 "

1'-0

" SLSIDE DRIFTS

Plan

Configuration after design earthquake

b 8+00

b 9+00

V A ULT

`

V A ULTTRA N SITIO N

V A ULTTRA N SITIO N

b 8+00

b 9+00

V A ULT

`

V A ULTTRA N SITIO N

V A ULTTRA N SITIO N

Section

8.5ft 8.5ft

carrier pipei.d: 6ft; length: 85ft

Mokelumne Aqueduct No. 3

Elastomeric seismic isolation bearing install on 351 pipe supports

San Pablo Dam Seismic Upgrade

Chabot Dam Seismic Upgrade

Dam Remediation Design Alternatives

Cement Deep Soil Mixing (CDSM)Conventional Earth Replacement

Questions

Timothy McGowan

Associate Civil Engineer

P.O. Box 24055

Oakland, CA 94623

(510) 287-1981