Earthquake Preparedness and Countermeasures in Osaka Municipal Waterworks Bureau

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Earthquake Preparedness and Countermeasures in
Osaka Municipal Waterworks Bureau

• Osaka Municipal Waterworks Bureau
• Kazuya YAMANO

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Osaka Municipal Waterworks
Purification plants 3
plants Distribution pipes
5,000 km Water supply capacity 2,430,000 m3/day
Area 211km2 Population2.6 million
OSAKA City
Kobe City
Japan
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Outline of Earthquake Preparedness Efforts
Kobe Earthquake (1995)
Earthquake Preparedness Improvement Plan 21(1996)
Review of scenario earthquakes (2004)
Investigation of seismic motion
Tsunami
Estimation
Estimation
Improving earthquake preparedness
Damage of distribution pipes
Influence on purification plants
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Outline of Earthquake Preparedness Efforts
Kobe Earthquake (1995)
Earthquake Preparedness Improvement Plan 21(1996)
Review of scenario earthquakes (2004)
Investigation of seismic motion
Tsunami
Estimation
Estimation
Improving earthquake preparedness
Damage of distribution pipes
Influence on purification plants
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Osaka Municipal Waterworks Earthquake
Preparedness Improvement Plan 21
8 Basic Elements

• Improving Earthquake Resistance of Key Facilities
• Establishing a Water Supply and Distribution
  Center Network
• Improving Compatibility among Different
  Distribution Systems
• Countermeasures against Power Failure
• Expanding Emergency Material Stock System
• Establishing Stable Water Supply Routes to
  Man-made Islands
• Improving Reliability of Information and
  Communication System
• Improving Earthquake Resistance of Headquarters
  Necessary for Disaster Relief and Recovery
  Activities

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Earthquake Preparedness (1)
Improving earthquake resistance of distribution
pipe network
Length of cast iron pipes
1,278 km (1997) 870 km (2005)
Ductile Iron Pipe
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Earthquake Preparedness (2)
Increasing capacity of drinking water reservoirs
Capacity of distribution reservoir
Nagai 42,000 ?
KUNIJIMA
Sakishima 30,000 ?
Total 72,000 ? UP
JOTO
OYODO
OTEMAE
TATSUMI
MINATO
Osaka City
SUMIYOSHI
SUMINOE
Distribution Plant (existing)
Distribution Plant (newly-built)
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Earthquake Preparedness (3)
Sufficiency of emergency materials
Polyethylene Bag (3L, 10L)
Water Supply Truck
Pipe Stock
Temporary Water Tank(4m3)
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Earthquake Preparedness (4)
Realization of effective emergency activity
Disaster InformationManagement System
Headquarters
Instructions
Report
Disaster Site
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Outline of Earthquake Preparedness Efforts
Kobe Earthquake (1995)
Earthquake Preparedness Improvement Plan 21(1996)
Review of scenario earthquakes (2004)
Investigation of seismic motion
Tsunami
Estimation
Estimation
Improving earthquake preparedness
Damage of distribution pipes
Influence on purification plants
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Scenario Earthquakes
(c)
(b)
(a)
(d)
(a) Uemachi fault (b) Ikoma fault (c)
Arima-Takatsuki-kozosen fault (d) Chuo-kozosen
fault (e) Nankai trough (Tonankai-Nankai
Earthquake)
Tsunami
(e)
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Outline of Earthquake Preparedness Efforts
Kobe Earthquake (1995)
Earthquake Preparedness Improvement Plan 21(1996)
Review of scenario earthquakes (2004)
Investigation of seismic motion
Tsunami
Estimation
Estimation
Improving earthquake preparedness
Damage of distribution pipes
Influence on purification plants
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Tonankai Nankai Earthquake (1)
Earthquake Occurrence Probability (within next 30
years)
- Tonankai Earthquake about 60 - Nankai
Earthquake about 50
Scenario Earthquake
Committee on Tonankai Nankai Tsunami
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Tonankai Nankai Earthquake (2)
Earthquake Occurrence Probability
Scenario Earthquake
- Simultaneous Occurrence of Tonankai Nankai
Earthquakes - JMA Magnitude 8.4
Committee on Tonankai Nankai Tsunami
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Tonankai Nankai Earthquake (3)
Earthquake Occurrence Probability
Scenario Earthquake
Committee on Tonankai Nankai Tsunami
Chairperson Prof. Kawata ( Kyoto Univ. )
Members Osaka City, Osaka Pref., Wakayama Pref.
Osaka City
Making map of inundation by Tsunami
Possibility of tsunami going over Yodo River
Large Weir revealed
Inundation map
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Preparedness against tsunami caused by Tonankai
Nankai Earthquake
Committee on the Influence on Water Treatment by
Tsunami in Yodo River
Examination of Intake of Kunijima purification
plant along Yodo River
(2) Turbidity
(1) Chloride ion
Upper Flow
Yodo River
Intake of Kunijima P.P
Yodo River Large Weir
Overflow
Kunijima P.P 1,180,000m3/day
Lower Flow (Osaka Bay)
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Tsunami simulation
Tsunami simulation
Yodo River
Model of seismic source
Kobe
Osaka
Yodo River Large Weir
Japan
Osaka Bay
Tonankai
Nankai
(River flow 196m3/s)
JMA Magnitude 8.4
Tsunami arrives at the Yodo River estuary within
2 hours and the Yodo River Large Weir within 2.5
hours after the earthquake.
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Chloride Ion Concentration
Tsunami simulation
Chloride ion concentration
Yodo River
Kobe
Osaka
Intake point
Adjustment gate
Upper Flow
Lower Flow (Osaka Bay)
Maximum height of tsunami ( m )
Yodo River Large Weir
Main gate
Yodo River Large Weir
Kema Lock Gate
Adjustment gate
(River flow 196m3/s)
Kema Water Gate
Okawa River
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Conclusion
Time of concentration being over standards (h)
At Intake point, maximum concentration of
Chloride ion is about 1,000 mg/L and maximum
duration of concentration level exceeding water
quality standards is about 1 hour.
Necessity of preparedness against tsunami
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Outline of Earthquake Preparedness Efforts
Kobe Earthquake (1995)
Earthquake Preparedness Improvement Plan 21(1996)
Review of scenario earthquakes (2004)
Investigation of seismic motion
Tsunami
Estimation
Estimation
Improving earthquake preparedness
Damage of distribution pipes
Influence on purification plants
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Investigation Flow Chart
Collection and organization of data relevant to
seismic damage of distribution pipes
STEP2
Making damage ratio equations
STEP3
Damage estimation of distribution pipes based on
scenario earthquakes
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Points of the Review

• Upgraded seismic damage data obtained from recent
  research on earthquake engineering
• New estimation of the seismic damages of
  distribution pipes in liquefied area

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Data Utilized (1)
? Previous research ?
?2km2km data near seismometers (JWWA1996,1998)?
29 areas
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Data Utilized (2)
?Present research?
Seismic Motion of Kobe Earthquake Reproduced
Damage Ratio of Distribution Pipes during Kobe
Earthquake
about 4,800 meshes
?250m250m data(JWWA1996)?
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Damage Ratio Equation
D0 a x (PGV - b)
D0 Average Ratio of Damage (points/km) PGV
Peak Ground Velocity (cm/s) a, b Coefficient
Constant
D D0 x C1 x C2
D Rate of Damage (points/km) C1 Diameter
Correction Factor C2 Ground Correction Factor
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Classification of Liquefaction (1)
Liquefaction Assessment
PL-value calculated by Osaka Municipal Waterworks
Bureau
Liquefaction Level as Classified by JWWA
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Classification of Liquefaction (2)
?Liquefied Ground?
- cumulo-probability density function
Liquefaction frequency ()
Liquefaction frequency ()
PL value
PL value
Relation between PL value and liquefied area
Relation between PL value and liquefied area
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Damage Ratio Equation (Non-Liquefied Ground)


Damage ratio (points/km)
Damage ratio (points/km)
PGV (cm/s)
PGV (cm/s)
D00.0065 x (PGV-15)
D00.0153 x (PGV-15)
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Damage Ratio (Liquefied Ground)


Damage ratio (points/km)
Damage ratio (points/km)
PGV (cm/s)
PGV (cm/s)
Reference
Reference
Average Damage Ratio2.56
Average Damage Ratio4.00
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Investigation Flow Chart
Collection and organization of the data relevant
to seismic damage of distribution pipes
STEP2
Making damage ratio equations

• Examining upper value of damage ratio
• Examining value of damage ratio in liquefied
  ground

STEP3
Damage estimation of distribution pipes based on
scenario earthquakes
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Advanced Investigation Plan
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Thank you for your attention!
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Vertical Two-Dimensional Box Model
Depth Direction
Flow Direction
Cell Move of water and suspended solid is ignored
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Tsunami Simulation
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Equations and Conditions (Tsunami Simulation)
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Equations and Conditions (Calculation of the
chloride ion concentration)
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Seismic Motion Damage of pipes
Seismic Motion of Kobe Earthquake Reproduced
Strongest Shaking Area
Damage Ratio of Distribution Pipes during Kobe
Earthquake
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PL Value
w(z) 10 0.5 x z
z Depth from surface
F 1 FL (FLFL1.0)
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Disaster Information Management System
Integrated Management
Seismic damage simulation function
Pipeline restoration
Disaster Emergency Activities Information
Management Functions
Emergency water supply
Facility restoration

• Support for information to citizens and Osaka
  City Disaster Countermeasures Headquarters