Anti-Seismic Measures on
Water Suppｌy
Introduction and Overview
Akira NITTA
Water Supply Division
Ministry of Health, Labour and Welfare
Government of Japan
Significant
earthquakes
in the
vicinity of
Japan
magnitude
（From Jan. 1996
to Jul. 2006）
Depth
(km)
Source:http://www.seisvol.kishou.go.jp/eq/higai/higai1996-new.html
Recent Major Earthquakes in Japan
■ Kobe Earthquake
- January 17,1995
◆ Epicenter: beneath Kobe City
◆ Richter magnitude scale: 7.3
◆ Fatalities : more than 6,000
◆ Disruption of water supply : about 1.3
million households just after the disaster,
the amount of damage reached about 56
billion JPY (460 million US$)
◆ Emergency restoration of water supply
facilities : took about 3 months
Kobe Earthquake
- Jan 17,1995 -
←Damage to Buildings in
Kobe City
Damage to Water Pipes →
（φ８００ｍｍ）
Kobe Earthquake
- Jan 17,1995 -
Fires happened frequently, and a lot of houses were burnt down.
Kobe Earthquake
- Jan 17,1995 -
The sixth floor of the city office was crushed.
Recent Major Earthquakes in Japan
■ The Mid Niigata Prefecture Earthquake
- October 23, 2004
◆ Epicenter: mountainous region
◆ Richter magnitude scale: 6.9
◆ Fatalities : 40
◆ Injuries : about 4,500
◆ Disruption of water supply : about 130
thousand households
◆ Emergency restoration of water supply
facilities : took from 1 to 2 months
The Mid Niigata Prefecture Earthquake
- Oct 23, 2004 –
Damage to Small-scale Water
Supply Facility due to Landslide
The Mid Niigata Prefecture Earthquake
- Oct 23, 2004 –
Damage to water pipes under the ground
The Mid Niigata Prefecture Earthquake
- Oct 23, 2004 -
Emergency Water Supply by Water Wagon
Damage to water facilities at the Mid
Niigata prefecture earthquake

Damage to water treatment plants and
distribution reservoirs
・Large plants and reservoirs were slightly
damaged
・Small plants and reservoirs in the mountain
area were seriously damaged by breakdown of
surrounding ground. These were moved or
sagged and their functions were crashed.
・Private electric generator for emergency didn’t
start up immediately because of groundwater
influx and damage to the peripheral pumps and
equipments such as coolant water pumps.
・Antiseismic reinforced facilities were taken no
damage.
Damage to water facilities at the Mid
Niigata prefecture earthquake

Damage to pipe lines
・The ratio of damage to pipe lines was less than
the Kobe earthquake.
・The most damage hit the soft grounds,
developed lands banking area and slopes, which
is the same tendency of the Kobe earthquake.
・The pipe lines in the mountain area were flown
out with the slope and road failures.
・It was ascertained that antiearthquake
measures to pipe lines and renewal of decrepit
pipe lines based on the knowledge obtained by
Kobe earthquake were effective.
Measures at the hardware side

Antiseismic reinforcement of water supply facilities
 Create earthquake-resistance standards of facilities
 Development of promotion program to enhance
earthquake safety to facilities
 Promotion of improvement to supply main medical
centers with quake proof water distributing pipes
 Urgent renewal of aging and weak pipelines





Securing of reservoir capacity at distributing reservoir
→ securing capacity for 12 hours
Installation of emergency cutoff valves
Looping of pipe lines
Multiplication of water resources
Development of emergency water supply bases
Effective precaution for water supply
-BuildingsSeismic damage depends
on ground condition and
peripheral land form
・It is important to select location of facilities
and foundation structure cautiously.
・Don’t select high groundwater level area,
steep slope and mounded lands.
Effective precaution for water supply
-Pipe lines・Use earthquake-resistant pipes
Coated steel pipes
Ductile cast-iron pipes with earthquakeresistant joints
Polyethylene pipes with electric fusion joint
・Construct bypass and looped pipelines
Cost-effectiveness analysis is necessary
Earthquake-resistant joint of
Ductile Cast-Iron Pipe
Rate of earthquake-resistant
waterworks facilities and pipelines
耐震化率（％）
Rate of earthquake-resistant(%)
100
90
80
70
60
50
40
30
20
３０％
１４％
２０％
10
0
Water浄水場
treatment
plants
配水池
Distribution
reservoirs
基幹管路
Main
pipelines
Emergency cut-off valves
Emergency water supply bases
Emergency water supply bases in Tokyo
source：http://www.waterworks.metro.tokyo.jp/pp/suido/kyusui_point.htm
Measures at the software side

Development of emergency water supply planning
- Securing of other water supply method and water
resource and emergency water delivery route for
residents
 Cooperation agreement between waterworks
- Emergency supply and rehabilitation assistance to
the waterworks affected by earthquake from other
unaffected waterworks
 Cooperation with relevant institutions such as
sewerage
- Communicate information about influx to water
resources from raw sewage and industrial
wastewater
- Coordination of restoration of water supply and
sewage line
Rescue operation
・Information
gathering
Enhancement of
emergency
water supply
・Emergency
repair
・water supply
by transport
・Secure
manpower and
accept support
from other
・water supply
at base points
Fast restoration
Waterworks Vision
Measures to Improve the Quality of the Future Water Supply Service (November 1990)
Long-Term Objectives for Development of the Water Supply Service for the 21st
Century (Clean Water Supply Service) (June 1991)
Ideal Water Supply Service and Water Administration in the 21st Century
(Panel on Basic Issues Concerning Waterworks, July 1999)
Partial Amendment to the Waterworks Law in 2001
Changing environment surrounding
the water supply in Japan
Growing concerns over issues
related to waterworks
Analysis and evaluation of the current and
future prospects of the service
Ideal water supply service in the future
Setting common goals among parties involved in the service
Defining future policy issues
Clarifying specific measures and actions to be taken
Waterworks Vision (2004)
Ideal water supply
service
Water supply
system that strives
to be a leading
player in the world
Setting higher goals and
making steady progress
Service that customers
are always satisfied with
and are willing to
support
Providing a worldclass service in
various contexts
<Safety > < Stability >
< Sustainability >
< Environment >
< Globalization >
Policy objectives
Promotion of
measures
1) Safety
Supply people with safe and
good-tasting tap water
2) Stability
A stable supply of water for
domestic use anytime,
anywhere
3) Sustainability
• Strengthening the basis of
the water supply system
taking local characteristics
into account
• Preserving and developing
practices and skills
accumulated in the water
supply service
• Improving the water supply
service based on customer
needs
4) Environment
Contribute to environmental
conservation
5) Globalization
Contribute to the world by
transferring our experiences
to other countries
(1) Strengthening the
basis of the water
supply system
(2) Ensuring a safe and
convenient water
supply
(3) Improving disaster
prevention
(4) Improving
environmental and
energy measures
(5) International
contributions in the
water supply service
through international
cooperation
Thank you very much
for
your kind attention!