Seismic Service PresentationBrown and CaldwellORWARN 2011

September 28

Common Damage to Treatment Plants and

Systems; Analysis Examples

Don Ballantyne PEPrincipal, Degenkolb Engineers

Overview• Earthquake terminology and hazards

– Shaking– Liquefaction

• Common earthquake damage – Treatment plants and pump stations– Tanks– Pipelines

• Pipeline Design• System Risk Analysis Examples

– Portland– Seattle– Santa Clara Valley WD– Joint Water Commission WTP

• Magnitude – Richter or Moment Magnitude– Measure of energy release– 32 times more energy for increase of 1

• Peak ground acceleration (PGA) % of gravity

• Permanent ground deformation (PGD)

Earthquake Terminology

Pacific Northwest Earthquake Source Zones

1) Crustal Earthquakes (<15 miles deep) occur within the North American Plate on faults such as Seattle, Tacoma, and South Whidbey Island.

2) Deep Earthquakes (>40 miles deep) occur within the subducting Juan de Fuca Plate. Five M6 events in the last century. Nisqually Earthquake.

3) Cascadia Subduction Earthquakes occur about every 500 years at the boundary between the Juan de Fuca and North American plates. An M9 event occurred on January 26, 1700.

Liquefaction

San Fernando Earthquake,

1971

Philippines, 1990

Costa Rica, 1991

LiquefactionHigh liquefaction susceptibility  in many valleys because of high water tables in river valleys with young geologic deposits.

Liquefaction/ Duration Effects

M8.1 Peru, August 2007170 second duration

Japan – 4/11/11. Liquefaction‐induced differential settlement around tanks – WTP in Kashima City. Water supply suspended to 2.23 million households requiring 2 months for restoration. Liquefaction caused damage at 4 WTPs and 1 WWTP. 18 WWTPs damaged mainly from tsunamis

Treatment Plants and Pump Stations

Kobe City Hall

Annex

10

Rinconada Treatment Plant

Kobe Japan 1995 –Higashinada WWTP Liquefaction

2 meters lateral and 1 meter vertical movement

Higashinada WWTP Liquefaction

Higashinada WWTP Liquefaction

Pile failure under end of aeration basin

ESSBIO WWTP Conception Chile, 2010 Soil Failure

Tank Damage –Elephant’ Foot Buckling

Tank Moves and Breaks Pipe

Landers 1992

Roof Damage from Sloshing

1 MG Tank, Calexico, 2010

Elevated Tanks Collapse

Wire Wrapped Concrete Tanks

Pipe Failure  Jensen WTP 81”

Raw Line

21

Joint Pull Out ‐Kobe, Japan, 1995

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 Rates/km - Number of FailuresDIP CIP PVC Steel AC

PipeLlength (km) 1874 405 232 30 24Barrel 0 9 0.63 257 0.38 88 0.33 10 1.24 30Fitting 0 1 0.31 124 0.17 40 0.03 1 0.04 1Pulled Joint 0.47 880 0.49 199 0.33 76 0 0 0.37 9Joint Failure 0 2 0.06 25 0.5 115 0.07 2 0.08 2Joint Intrusion 0 5 0 1 0.01 3 0 0 0 0

Failure Mode

Floating Sewers

Kobe, Japan 1995

Floating Sewers

Japan 2011

Courtesy SEAW

Courtesy SEAW

Source: Tokyo University Report on Damage to the h b h

6 feet 4 inches (1.9m) of uplift

Pipe Characteristics Affecting Seismic Performance

• Ruggedness – material strength or ductility to resist shear and compression failures.

• Bending – beam strength or material ductility to resist barrel bending failures.

• Joint flexibility – joint and gasket design to allow elongation, compression, and rotation.

• Joint restraint – a system that keeps to joints from separating.

Relative Earthquake Vulnerability of Water Pipe

B&S - bell & spigot; RG - rubber gasket; R - restrained; UR - unrestrained

Material Type/Diameter

AWWA Standard Joint Type Ru

gged

-ne

ss

Bend

ing

Join

t Fl

exib

ility

Join

t Re

stra

int

Tota

l

(out

of 2

0)

Ductile Iron C1xx Series B&S, RG, R 5 5 4 4 18Polyethylene C906 Fused 4 5 5 5 19Steel C2xx Series Arc Welded 5 5 4 5 19Steel None Riveted 5 5 4 4 18Steel C2xx Series B&S, RG, R 5 5 4 4 18

Concrete Cylinder C300, C303 B&S, R 3 4 4 3 14Ductile Iron C1XX Series B&S, RG, UR 5 5 4 1 15PVC C900, C905 B&S, R 3 3 4 3 13Steel C2xx B&S, RG, UR 5 5 4 1 15

AC > 8" D C4xx Series Coupled 2 4 5 1 12Cast Iron > 8" D None B&S, RG 2 4 4 1 11PVC C900, C905 B&S, UR 3 3 4 1 11Concrete Cylinder C300, C303 B&S, UR 3 4 4 1 12

AC <=8" D C4xx Series Coupled 2 1 5 1 9Cast Iron <= 8" D None B&S, RG 2 1 4 1 8Steel None Gas Welded 3 3 1 2 9

Cast Iron None B&S, Rigid 2 2 1 1 6High Vulnerability

Low Vulnerability

Low/Moderate Vulnerability

Moderate Vulnerability

Moderate/High Vulnerability

BAD

GOOD

JWWA Standard/Seismic Joint

240 km of Japanese “S” joint had no failures

installed in the worst geotechnical conditions in

the Kobe earthquake.

JWWA standard requires pipe to be able to accommodate 1% strain in liquefiable soil areas.

Stops

Recommended Pipe Selection• Most pipe is selected from a standard, and no seismic 

analysis is performed

• Rule of thumb – PGA < 40%g and No PGD– Commonly used pipe OK – DIP, PVC, CCP.

– Do not push joints home – allow for expansion and compression

• PGA > 40%g. – Welded steel, restrained joint DIP, HDPE

– PVC – brittle. One user in Northridge believed deep bell aided performance

Recommended Pipe Selection ‐ continuedFor pipe subjected to PGD

• Continuous pipe– Steel with welded joints

• Avoid mortar lined as it can spall off when the pipe displaces

• Avoid concrete coating as it forces strain to the joints

– HDPE with fused joints

• Segmented pipe with restrained joints– Ductile iron

– Provide capability to extend/compress to relieve strain • Expansion couplings

• Position spigot in bell to accommodate expected extension or compression.

Design for PGD• Relocate the pipe to different corridor• Install below liquefiable layer 

– Directional drilling or micro tunneling– Useful for river crossings

• Improve the soils to reduce liquefaction/lateral spread– Gravel columns– Soil mixing

• Support the pipe on piles (designed for lateral spread loads)

• Gravity sewers – hold‐downs to keep from floating using augers (such as used in the gas industry)

Design for PGD ‐ continued• Design the pipe to move, e.g., pulling it through the soil• Applicable to continuous & restrained joint pipe• Design layout to put pipe in tension• Minimize anchors to allow the pipe to slide through the 

ground to distribute the strain– Bends and tees, valves, and valve boxes– Service connections – provide special flexible designs– Location next to hard points, such as other infrastructure

• Provide flexibility at connections to structures• Use shallow “V” trench and light backfill to allow 

movement

• Wrap pipe in polyethylene – reduce soil/pipe friction

• Perform non‐linear analysis

Existing System Mitigation 

• Replace existing pipe with low vulnerability pipe– Japanese are aggressively replacing CIP in poor soils.

– In U.S. wholesale replacement seems to be difficult to justify. A recent study was not able to demonstrate a benefit‐cost ratio > 1. Focus on critical lines.

• Slip line pipe with ductile material such as HDPE

• Provide a hardened backbone supplemented by a system of pumps– San Francisco and Vancouver have seismic resistant dedicated fire protection systems

• Provide redundancy from multiple sources and/or feeds to critical locations

• Install/maintain isolation valves aroundvulnerable areas

• Provide emergency response capabilities(pumps and hoses)

• Improve capability for quick restoration– Material and equipment availability

– Mutual aid

Existing System Mitigation ‐ continued

Pipeline Summary• Pipeline damage is the primary cause of water system 

failure in earthquakes

• Earthquake shaking and PGD cause pipelines to fail

• Liquefaction, the most common form of PGD, typically occurs along water bodies and in alluvial deltas

• Cast iron pipe with brittle leaded joints is the most vulnerable pipe

• For new pipelines, ductile pipe systems provide the best reliability for PGD

• Existing system vulnerability can be mitigated by providing redundancy and enhancing the capability to provide emergency response

• Functionality (Level of Service)– Capacity/Probability of 

achieving• Planning & Response

– Emergency planning– Emergency response – Near‐

Real‐Time Assessment– Restoration planning

• Financial– Direct losses– Insurance coverage 

assessment– Post‐event financial planning– Reliability assessment for bond 

sales

• Social Impacts/Indirect Losses– Outage time– Capacity during recovery– Business interruption – end 

users– Resilient community goals

• Asset Management/Capital Improvements– Identification of deficiencies– Prioritization of capital 

improvements– Benefit/cost analysis– Input to asset management 

plan (annualized loses)

System Risk Analysis

Hazard Quantification

•Scenario based•Groundmotion

• PGA, PGV, Spectral

• Spectrum

•Liquefaction probability•Lateral spread PGD

Component Fragilities

•Published•Empirical•Test data•Analytical

Component Impacts

•% replacement cost•Functionality/ reduced capacity•Outage time

System Analysis•Direct losses•Capacity/ probability•Outage time•Capacity during restoration

Business Interruption/    Societal Losses

•Daily outage per capita $•% GRP•Business specific losses

System Risk Analysis Methodology

City Center

Mt. Hood

Bull Run WatershedColumbia

River

Powell Butte Reservoir

Groundwater System

Willamette River

Sandy RiverLandslide Area

l Bull Run Watershed - some components built in early 1900’s

l Transmission 3 – 40 km conduitsl Columbia Well Field – built in 1980’sl Treatment - chloramination, pH

adjustmentl Distribution – primarily cast iron

Portland Water Supply System

Portland Distribution System Assessment

Portland GIS/HAZUS- Analysis Input

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

1% 10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Peak Ground Acceleration

Prob

abili

ty o

f Fai

lure

Pipe Material/Facility Information

Damage/Fragility FunctionsLiquefaction Susceptibility

Ground Motion Scenario -Subduction Earthquake

Pipe Material Joint Type K2Cast iron Cement 1Cast iron Rubber gasket 0.8Cast iron Mechanical restrained 0.7Welded steel Arc welded (large

diameter, non corrosive)0.15

Welded steel Rubber gasket 0.7Asbestos cement Rubber gasket 0.8Asbestos cement Cement 1Concrete w/Stl Cyl Welded 0.6Concrete w/Stl Cyl Cement 1Concrete w/Stl Cyl Rubber gasket 0.7PVC Rubber gasket 0.8Ductile iron Rubber gasket 0.5

Repair Rate/1000 feet = K2* (1.06) * PGD0.319

Repairs taken as 80% breaks and 20% leaks for PGD

ALA Repair Rate - PGD

0.000.501.001.502.002.503.003.504.00

0 10 20 30 40 50

PGD (inches)

Rap

air R

ate

(1,0

00 ft

) CIP

DIP

Steel

ALA Damage Relationships ‐ PGD

Importance Factors

Recommended mitigation of pipelines in liquefiable soils across/ along Willamette 

River. 

Supply System Reliability, 500‐Year Return Earthquake

0.00.10.20.30.40.50.60.70.80.91.0

50 100 150 200 250 300 350Flow (mgd)

Prob

abili

ty o

f sup

plyi

ng a

t le

ast "

x" m

gd

No Intertie

Intertie

Portland Earthquake Reliability

Supply System Reliability, 100‐Year Return Earthquake

0.500.550.600.650.700.750.800.850.900.951.00

50 100 150 200 250 300 350Flow (mgd)

Prob

abili

ty o

f sup

plyi

ng a

t le

ast "

x" m

gd

No Intertie

Intertie

Meets 100‐year return reliability of 145 mgd

Requires mitigation to meet 500‐year return reliability of 95 mgd

Permanent Ground Deformation for 500‐year 

Earthquake

Seattle Water

Santa Teresa WTP

Santa Teresa WTP

VasonaPump Station

Rinconada WTP

Rinconada WTP

Penitencia WTP

Penitencia WTP

PachecoPump Station

Santa Clara Conduit

Cross Valley Pipeline

Calero Pipeline

Almaden Valley PL

VasonaValve Yard

CoyotePump Station

SFPUC IntertiePump Station

East Pipeline

West Pipeline

Snell Pipeline

Parallel E Pipeline

Milpitas Pipeline

CentralPipeline

PiedmontValve Yard

San LuisRes. Intake

Anderson/Coyote

South Bay Aqueduct

Bay DivisionPipeline 3&4

Calero Dam & Reservoir

Treated Water System

Raw Water System

WaterSources

Santa Clara Valley WD System Hydraulic & Reliability Models

SCVWD Reliability Model

• The Model consists of:– Detailed Hazard Models 

– Facility Vulnerability Models

– Pipeline Vulnerability Models

– Model of system water sources, pressures and flows

– System reliability simulation model

– System restoration model

• Fault Tree/Connectivity Model similar to Portland

• Output is probability of meeting Level of Service Criteria at retailer turnouts

San AndreasEarthquake

M7.9

378 year Event

Controlled by Fault Rupture

Controlled by Liquefaction

Pipeline ModelsSan Andreas Earthquake

System Critical Facilities Status –San Andreas Earthquake ‐ Baseline Analysis

Recommendations Prioritized 

Highest Benefit/Cost RatioNear proposed service level goalsReduces outage period for other eventsBalances cost and reliability

Portfolio 2 Recommended

Table 4.2 from SCVWD Water Infrastructure Reliability Project Report

JWC Water Treatment Plant

72 MGD plant

Built in 4 stages, 1974 through1998

Plant founded on liquefiable soils

Level of Service GoalsLOS Parameter

72-Year Event 475-Year Event 2,475-Year Event

Capacity

Peak Season Average Daily

Demand (ADD) (42 MGD)

Winter Average Daily Demand (WADD) (28

MGD)

Restoration Time

Immediately following event

Within 24 hrs

½ WADD for 3 days;WADD

for 7-14 days;Average

Annual DD for 60-90 days

Damage State Descriptions, Functionality and % Replacement

Description Function-ality

Restoration Cost (% of replacement

cost)

Light Minor cracking; minimal structural strength degradation; equipment secure;

Remains functional

5%

Moderate

gravity load bearing elements functional; some residual strength; no

out-of plane wall failures; many architectural systems damaged;

Not functional

30%

Severe

little residual structural strength; some structural failures but load bearing

members remain functional but near collapse; extensive equipment damage;

Not functional

100%

Evaluate baseline performance and 4 upgrade packages against 3 events –72, 475, and 2,475 events (ASCE 31‐03)

Design Upgrade Packages to Meet Levels of Service• Evaluated baseline performance for 3 earthquake levels (72, 475, 2,475 yr return)

• Identified WTP components required to meet level of service goals ‐ capacity

• Selected upgrades to meet performance criteria – continuous operation, restoration time

• Evaluate performance for smaller and larger earthquakes

Upgrade Packages to Meet Performance Objectives

Capital Cost ($ millions)Package Goal

Increment Total

1 Life Safety $2.86 $2.86

2A 72-yr $0.19 $3.05

2B On-site Power Generation

$3.00 $6.05

3 475-yr $17.75 $23.80

4 2,475-yr $0.10 $23.90

Economic AssessmentBenefits are the Avoided Losses

Direct damage

Equipment rental to emergency operation

Loss of revenue

Cost to provide emergency water until temporary operation is restored

Business interruption suffered by end‐use customers (secondary loss)

Avoided losses - the “Benefit” in the Benefit/Cost Ratio

Benefit‐Cost Summary (w/o BI)

BL           LS          72A       72B        475       2,475

• Functionality (Level of Service)– Capacity/Probability of 

achieving• Planning & Response

– Emergency planning– Emergency response – Near‐

Real‐Time Assessment– Restoration planning

• Financial– Direct losses– Insurance coverage 

assessment– Post‐event financial planning– Reliability assessment for bond 

sales

• Social Impacts/Indirect Losses– Outage time– Capacity during recovery– Business interruption – end 

users– Resilient community goals

• Asset Management/Capital Improvements– Identification of deficiencies– Prioritization of capital 

improvements– Benefit/cost analysis– Input to asset management 

plan (annualized loses)

System Risk Analysis/Questions?