Donald Ballantyne Regional Water Providers
October 2, 2013
Consortium Board
Understanding the Seismic Vulnerability of Water Systems
–
Lessons Learned and What You Can Do
Overview
• Oregon Resilience Plan
• Historic earthquake
performance
• Seismic risk and earthquake
hazards
–
–
–
–
•
•
•
•
•
Liquefaction
Cascadia Subduction Fault
Portland Hills Fault
Canby‐Moalla Fault
Expected performance
Desired performance
How are we going to get there?
Emerging seismic resistant pipe
Questions
Oregon Resilience Plan
• After 2 weeks without services, people leave;
many don’t come back
• Keep the supply and transmission system
operable (fire suppression)
• Restore distribution within
2 weeks
Historic Earthquake Performance
• Tohoku, Japan 2011 ‐ 40+ days
• Christchurch, New Zealand 2011 – 40+ days
• Kobe Japan, 1995 – 60 days
– 1,200 pipeline failures
• Northridge, California 1994 – 13+ days
– 1,000 distribution
failures
– 35 transmission
main failures
Tohoku
Earthquak
e
Kanigawa WTP
Utilidore
floated
Pipes
sheared
off (typ)
Tohoku ‐ Pipe Performance
No failures in Kubota seismic joint pipe
Failure of 2.4M DIP, Sendai
Tohoku, Japan 2011
Floating Sewers
Photo Credit SEAW
JWWA Manual for Emergency Countermeasure
JWWA Emergency Water Supply Operations
Emergency water supply
vehicles – maximum of
430/day
Lining up at a base water
supply facility
Set up of canvas tanks
Water supply at an emergency
medical establishment
Tohoku Fuel Shortage
Damage to Water Supply
・Limited accessibility to gasoline, light oil, and kerosene.
・ Difficult to obtain fuel for electric generators, water
trucks, official vehicles, and specialized task vehicles etc.
Tank
Capacity
（L)
Operational
Hours/ Tank
Capacity
Kerosene
6,500
28.7
March 14
Light Oil
950
13.1
54
March 13
Kerosene
12,000
29.4
68
March 14
Kerosene
10,000
29.9
Water
Purification
Plant
Electric Generator
Operation Hours
Moniwa
98
March 15
Kunimi
58
Nakahara
Fukuoka
Return of
Type of Oil
Electricity
Water Restoration Timeline ‐ Sendai
Main trunkline restoration
Distribution area restoration
★
★
Aftershock
occurred
Distribution area restoration
Began receiving water
from the Sennan Senen
Regional Area to Sendai
Distribution area restoration
Earthquake occurred
The number of the water suspension
×1,000 houses
★
Transmission pump failure
Sennan Senen Regional Area
water distribution secured by
rerouting water system
Distribution station
restoration
Received water from distribution
station
Christchurch NZ
Feb 22, 2011
 City of 360,000 people
 M6.3 Direct Hit
 190 fatalities
 CBD destroyed, 1,800 buildings demolished
 55,000 residences damaged
 $25‐$30B damage; 20% of GDP
 Extensive liquefaction along
the Avon River
Christchurch NZ
 1645 water pipeline repairs
out of 1000 miles pipe
 Most was AC pipe
 Have moved to HDPE
 300 km of sewer damaged
 8 PS require replacement
 Chemical toilets distributed
to 30,000 residents
Kobe, Japan 1995
Pipe joint pull out due
to liquefaction
Over 1/2 of the failures were due to joint
pull out. Pipeline damage rates for the Kobe
earthquake are shown in the table below.
Failure Mode
PipeLlength (km)
Barrel
Fitting
Pulled Joint
Joint Failure
Joint Intrusion
Failure Rates/km - Number of Failures
DIP
CIP
PVC
Steel
AC
1874
405
232
30
24
0
9 0.63 257 0.38 88 0.33 10 1.24 30
0
1 0.31 124 0.17 40 0.03
1 0.04 1
0.47 880 0.49 199 0.33 76
0
0 0.37 9
0
2 0.06 25
0.5 115 0.07
2 0.08 2
15
0
5
0
1 0.01
3
0
0
0 0
Kobe, Japan 1995
Lateral Spread
Resulting in Pulled
Joint
Lateral spreading resulted in DIP
joint separation
16
Liquefaction Damage
to Treatment Plants
Higashinada Wastewater
Treatment Plant, Kobe, Japan
1995
Northridge 1994
Buried Pipe Failure
Jensen WTP 81”
Raw Line
Northridge 1994
Tank Damage –
Elephant’ Foot
Buckling
Northridge 1994
Tank Damage
Inadequately attached roof slid
Rocking tank separated
piping
Loma Prieta 1989
Wire Wrapped
Concrete Tanks
Regional Earthquake Hazards
• Tsunami – only on the coast
• Liquefaction
• Cascadia Subduction Fault, (Magnitude 9.0);
500‐year recurrence (last event 1700)
• Portland Hills; East Bank Fault (Magnitude 6.8)
• Canby‐Moalla Fault
Sendai WWTP Pump Station hit by
tsunamis, Japan 2011
Tsunamis
Liquefaction
Loss of bearing
Liquefaction
Loosely packed
sand grains
 Occurs due to shaking
 Soil particles consolidate
squeezing out water
 Water pore water pressure
increases reducing friction
between soil particles
 Soil becomes a viscous liquid
Costa Rica, 1991
Consolidated
sand grains
Lateral Spread
Pipeline
Initial Section
Design pipeline to move with
the soil blocks – expand to
relieve strain and be dragged
through the ground.
Soil Blocks
“Floating” on
Liquefied Material
X
Liquefied Material
X
X
X X
Deformed Section
X
X
Liquefaction
 Liquefaction
 Willamette,
 Columbia,
 Tualatin
Pacific Northwest Earthquake Source Zones
Cascadia
Subduction Zone
 500 year return period for full
length
 Most recent event 1700
 25% probability within next 50
years
 40% probability southern segment
Groundmotion Cascadia Subduction
 Higher ground motions
west of Portland
 Will impact older/poorly
engineered structures will
fail
 Long duration shaking will
cause liquefaction
Block Movement
• Movement in the North
American Plate
• Remnant from the northwest
movement of the Pacific Plate
• Western Oregon rotating
northwest
• Portland to Bellingham getting
squeezed ~ 10 mm/yr
• Differential movement results in
surface faults
Earthquake Faults
 Surface fault ruptures
could shear pipelines
 Ground motions stronger
near field damaging
 Tanks & structures
Portland Hills
Fault
Groundmotion
Fault Crossings
Recommendations from Resilient
Oregon Plan
•
•
•
•
•
•
•
•
•
•
Reset public expectations for recovery times
Require seismic assessments for all systems
Encourage water & fire agencies coordinate plans
Encourage upgrades; sanitary surveys & designs
Encourage business continuity plans
Encourage essential support for employee families
Establish seismic design standards for pipelines
Clarify regulatory expectations during emergency
Encourage participation in ORWARN
Plan for emergency water distribution
Seismic Assessments
Hazard
Quantification
•Groundmotion
•Liquefaction
Component
Fragilities
Component
Impacts
•Functionality
•Outage time
Business Interruption/
Societal Losses
•Daily outage per capita $
•% GRP
•Business specific losses
System Analysis
•Capacity
•Outage time
Pipe Damage Relationships
Repair Rate for Shaking Damage
Rate - PGD
Repair RateALA
forRepair
Ground
Deformation
CCP
CIP
DIP
Steel
Rapair Rate (1,000 ft)
4.00
3.50
CIP
3.00
2.50
DIP
2.00
1.50
Steel
1.00
0.50
0.00
0
10
20
30
PGD (inches)
40
50
Portland GIS Analysis Input
Pipe Material/Facility
Information
Ground Motion Scenario Subduction Earthquake
Pro b ability o f F ailu re
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
Peak Ground Acceleration
Liquefaction Susceptibility
Damage/Fragility Functions
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
1%
0%
Age (yrs)
Asset Inventory
Moved from UBC
Zone 2 to Zone 3
Facility
Component Reliabilities/Fragilities
1
0.9
Pump Bldg.
Control Bldg.
Reservoir
Wells
Well Collection Piping
Main Pumps
Substation
Control Equipment
Total
0.8
Reliability
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0
0.1
0.2
0.3
0.4
0.5
0.6
PGA (g's)
0.7
0.8
0.9
1
Example ‐ System Critical Facilities Status
Example ‐
Outage Maps
LADWP following
Northridge
Develop Recommendations;
Input into Capital Improvement Plan
• Identify vulnerable sections of transmission
system – replace as required
• Identify vulnerable pipelines within distribution
systems – replace with seismic resistant pipe
• Evaluate storage, pump stations – upgrade as
required
• Schedule mitigation to achieve desired
performance over 50‐years
Seismic Resistant Pipe
• Modern pipe works well in competent soils
• In liquefiable soils:
– Restrain joints
– Allow for strain
relief
Ductile Iron Pipe (DIP) AWWA C‐150
with Restrained Joint (Field‐Lok
Gasket)
Retainer
Seat
Gasket
z
z
Wedge
•
•
•
•
DIP Joint
Bell
DIP Joint
Spigot
Design to resist ground movement
Material strength and ductility
Restrained joint
Does not allow release of strain due to ground deformation
Ductile Iron Pipe Expansion Sleeve
EBAA Ex‐Tend
• Expansion sleeve for strain relief
• $900 ‐ 8”; $1,200 – 12” EBAA Ex‐Tend
• Proposed “custom” expansion sleeve – hook into the bell with a split
harness; about half the above cost
Japanese Seismic Joint DIP
• Restrained joint
• Allows expansion/compression
PVC (C‐900) with 2X Deep
Bell and Joint Harness
(Manufactured by Kubota)
• Vulnerable to corrosive soils
• Expansion can be provided for strain relief
Polyvinyl Chloride (PVC) AWWA C‐900
with joint restraint
Joint Harness – Add anode
caps on bolts?
Bulldog Joint – “Wedge”
Ring Embedded in Joint
• Vulnerable to corrosive soils ?
• No expansion allowed for strain relief
Molecularly Oriented PVC
AWWA C‐909
• Stronger/more ductile than C‐900
• Telescope (compress) without loss of
hydraulic integrity
High Density Polyethylene (HDPE)
AWWA C‐906 – Fused Joint
• Excellent performance in
Christchurch and Tohoku
earthquakes
• Relieves strain through
ductility
Summary
• Water systems have been heavily damaged in past
earthquakes
• Oregon is seismically active
• The Oregon Resilience Plan is pushing to mitigate
vulnerable facilities within 50 years
• Seismic vulnerability assessments can identify expected
damage and system performance in an earthquake
• Implementation of developing pipe
materials can help provide resilient
systems
Questions ?
Don Ballantyne PE
Ballantyne Consulting LLC
dbballan@comcast.net