1

Research Activities

on Earthquake-Proofing

of Drinking Water Facilities

by the Japan Water Research Center

W.Adachi （Japan Water Research Center） S.Uchikoshi （Japan Water Research Center ）

Y.Takahashi （Japan Water Research Center）

M.Fujiwara （Japan Water Research Center）

M.Miyajima （Kanazawa University ）

2

Presentation Outline

• Improvement of the earthquake

resistance of drinking water facilities

－ Earthquakes in recent years

－ History of earthquake resistance regulations

－ Earthquake resistance technology for water pipelines

• Surveys and studies by JWRC

－ Evaluation of the earthquake resistance of drinking

water facilities by performance indicators (PIs)

－ Equation to predict earthquake damage to pipelines

• Outline of JWRC

Outline of JWRC

3

4

Research &

Development

Technical

Supports

International

Activities

Japan Water Research Center

JWRC Ministry of

Health Labour

and Welfare

Water utilities

Universities &

research

institutes

Private

companies

Outcomes of Reserch and Development

Applications Public Relations Activities

Improvement of the earthquake resistance of drinking water

facilities

5

Collapsed Distribution Reservoir

Earthquakes in recent years

6.9 25 March,

2007

Noto Hanto

6.8 23 October,

2004

Mid Niigata

Prefecture

7.2 17 January,

1995

South Hyougo

Prefecture

Magnitude Date Name of

Earthquake

6.8 16 July,

2007

Niigata

Chuetsu-oki

7.2 14 June,

2008

Iwate-Miyagi

Nairiku

Off the Pacific

coast of Tohoku

11 March,

2011 9.0

Off the Pacific coast of Tohoku

(Source: Ichinoseki City

Waterworks Bureau )

6

Year Major earthquakes Major developments

1995 South Hyogo Prefecture

Earthquake (M7.2)

1997 ・The Guidelines for Earthquake-Resistant

Construction Methods for Waterworks

Facilities were revised ※1 ・Draft Guidelines for Planning to Upgrade

the Earthquake Resistance of Drinking-

Water Facilities were developed

2004 Mid Niigata Prefecture

Earthquake (M6.8)

2006 ・The Review Commission on the

Improvement of the Earthquake Resistance

of Water Pipelines produced a report

History of earthquake

resistance regulations

Table1 Revisions of seismic guidelines(1/2)

7

Level 2 ground vibration concept

Year Major earthquakes Major developments

2007 Noto Hanto Earthquake

(M6.9)

Niigataken Chuetsu-oki

Earthquake (M6.8)

2008 Iwate-Miyagi Nairiku

Earthquake (M7.2)

・The Guidelines for Planning to Upgrade

the Earthquake Resistance of Drinking-

Water Facilities were revised

2009 ・The Guidelines for Earthquake-Resistant

Construction Methods for Waterworks

Facilities were revised

2011 Off the Pacific coast of

Tohoku Earthquake (M9.0)

・Damage is being assessed and

earthquake resistance enhancements are

being developed

Table1 Revisions of seismic guidelines(2/2)

8

9

Level 1 ground vibration

Level 2 ground vibration

・・・Level 1 is the maximum level of earthquake which

may occur during the service period of the facility.

・・・ Level 2 is the maximum level of earthquake which

may occur at the site of the facility in the future.

Facility importance Rank A

・・・ Rank A are essential and non-replaceable facilities.

Facility importance Rank B

・・・ Rank B are other facilities.

Degree of

importance

Earthquake level

Level 1 Level 2

Rank A Operational capacity is

not affected.

Seismic damage is minor

and does not severely

affect operational capacity.

Restoration requires

minimum effort.

Rank B Seismic damage is minor

and does not severely

affect operational capacity.

Restoration requires

minimum effort.

Seismic damage is minor

and does not severely

affect operational capacity,

but restoration is necessary.

Table2 Level of required earthquake resistance

10

Earthquake resistance

technology for water pipelines

The main types of buried water pipes are

・Ductile cast iron pipes (DIP),

・Grey cast iron pipes (CIP),

・Steel pipes (SP),

・Polyethylene pipes (PE),

・Polyvinyl chloride pipes (PVC),

・Asbestos cement pipes (ACP).

CIPSP

PE

ACP Other

PVC

DIP

11

60%

As of 2008

Joint Characteristics

Type A A rectangular rubber gasket is placed around the socket and the joint

bolts are tightened with a gland.

Type T A rubber gasket is placed around the socket and the spigot is inserted

into the socket.

Type K A modified version of Type A. This has only a rubber gasket which a

rectangular one and a round one are combined.

Type S,

Type S-II

A rubber gasket and a lock ring are placed around the socket and the

spigot is inserted into the socket. The joint has good earthquake

resistance with high elasticity and flexibility and a disengagement

prevention mechanism.

Type NS Same earthquake resistance as Type S but is easier to use than Type S.

Table3 Characteristics of joint types for DIP

12

0.000

1.5081.430

1.782

0.4730.488

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

DIP(S,SⅡ)

DIP(A,K,T)

SP CIP PVC ACP

Dam

age R

ates(

num

ber/

km)

No Damage

Fig. Pipe damage in the 1995 South Hyogo Prefecture Earthquake

Rubber Gasket

Lock Ring

Centering Rubber Spacer Rubber Gasket

Lock Ring

Centering Rubber Spacer

Socket Spigot

Fig. Type NS joint

Surveys and studies by JWRC

14

Evaluation of the earthquake resistance

of drinking water facilities by

performance indicators (PIs)

What is PIs?

－ JWWA published “Guidelines for the Management

and Assessment of Drinking Water Supply Service”

in January 2005.

－ The Guideline defines 137 PIs (Performance

Indicators), including indicators for earthquakes.

JWRC has analyzed current situation

of water utilities in Japan using PIs. 15

Ratio of earthquake-resistant water treatment facilities

39

2219 17 19

22

1317 18

10 96 8 8 7 7 5 6

3

39

0

11

0

20

40

60

80

100

0

0-5

5-10

10-15

15-20

20-25

25-30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

80-85

85-90

90-95

95-<100

100

100<

2207 Ratio of earthquake-resistant treatment facility (%)

No

. o

f U

tilit

ies

0%

25%

50%

75%

100%

1182

12.3612.97

15.89 16.32

0

5

10

15

20

FY2005 FY2006 FY2007 FY2008

Rat

io o

f ea

rthq

uake

-re

sist

ant

trea

tment

fac

ilities

(%)

16

Ratio of earthquake-resistant water pipelines

201 202

130

9268

45 41 30 24 11 14 11 14 9 4 8 4 1 3 5 3 4 1 3 0 13

0

100

200

300

400

500

0

0-2

2-4

4-6

6-8

8-10

10-12

12-14

14-16

16-18

18-20

20-22

22-24

24-26

26-28

28-30

30-32

32-34

34-36

36-38

38-40

40-42

42-44

44-46

46-48

48-50

50<

2210 Ratio of earthquake-resistant pipeline (%)

No

. o

f U

tilit

ies

0%

25%

50%

75%

100%

573

17

15.18

12.0911.9310.80

0

5

10

15

20

FY2005 FY2006 FY2007 FY2008

Rat

io o

f ear

thquak

e-re

sist

ant

trunk

pipe

lines

(%)

Equation to predict earthquake

damage to pipelines

－ JWRC proposed an equation to predict

earthquake damage to water pipelines based on data

from the South Hyogo Prefecture Earthquake in

March 2000.

－ Later, with additional data from more recent

earthquakes, it was concluded that the extent of

damage is strongly linked with the kinds of pipe

materials, joint types, and topography.

JWRC has proposed a new equation to predict

earthquake damage .

Rm(v) = C1× C2 ×・・・ Cn × R(v) Rm(v): Predicted damage rate [locations/km]

R(v) : Reference damage rate [locations/km]

Cn : Correction factors

18

Attributes of damaged pipelines

Kobe, Ashiya, and Nishinomiya

ｰ (1995 South Hyogo Prefecture Earthquake; n = 2170)

Nagaoka and Ojiya ｰ (2004 Mid Niigata Prefecture Earthquake; n = 277)

Kashiwazaki and Kariwa

ｰ (2007 Niigataken Chuetsu-oki Earthquake; n = 491 )

developed a database in a geographical

information system (GIS)

●damage locations

●pipe attributes (pipe type, joint type, pipe diameter)

●the maximum velocity of ground vibration

●microtopography types （J-SHIS） 19

Reference damage rate equation

The reference damage rate was calculated from

the approximate curve obtained by the least-

squares regression equation relating to the

damage rate and the maximum ground surface

velocity.

R(v) = 9.92 × 10–3 × (v – 15)1.14

where R(v) = reference damage rate (locations/km)

v = maximum surface velocity of ground vibration (cm/s)

(15 ≤ v < 120). 20

Determining the correction factors in the damage

prediction equation pipelines

The values of the correction factors were

determined using cross-tabulation and

multivariate analysis based on mathematical

quantification theory class I.

Cross-tabulation

Multivariate analysis

Correction factors

Result: The damage rate by pipe type, joint type, pipe diameter

and microtopography type

The relationship of pipe type, joint type, pipe diameter

and microtopography class with the damage rate

Rm(v) = Cp × Cd × Cg × R(v) Rm(v): Predicted damage rate [locations/km]

R(v): Reference damage rate [locations/km]

= 9.92 × 10–3 × (v – 15)1.14

v: Maximum surface velocity of ground vibration (cm/s)

(15 ≤ v < 120)

Pipe type, joint Cp Diameter Cd

DIP (A) 1.0 ø50–80 2.0

DIP (K) 0.5 ø100–150 1.0

DIP (T) 0.8 ø200–250 0.4

DIP (disengagement prevention) 0 ø300–450 0.2

CIP 2.5 ø500–900 0.1

PVC (TS) 2.5

PVC (RR) 0.8

SP (welding) 0.5/0

SP (non-welding) 2.5

ACP 7.5

PE (electrofusion) N/A※

22

Microtopography with pipelines installed Cg

If there is no information available on liquefaction or

if there is no possibility of liquefaction

Mountain, mountain foot, hill, volcanic area, volcanic mountain foot,

volcanic hill 0.4

Gravel upland, loam upland 0.8

Valley floor, alluvial fan, backswamp, delta, coastal lowland 1.0

Natural levee, former river channel, sandbar, gravel bar, dune 2.5

Reclaimed land, drained land, lakes and marshes 5.0

If there is information available on liquefaction and if there is the possibility

of liquefaction

All topography types 6.0 23

Evaluation of the damage prediction equation

Predicted number of

damage locations per cell

0

0-4.0

4.0-8.0

8.0-12.0

12.0-16.0

16.0-20.0

Actual damage

location

Fig. Evaluation results for Takarazuka. Areas with 0 damage locations

have no pipelines or are not covered in the evaluation 24

Conclusions

・To evaluation at the national level, it is critical that

drinking water utilities calculate PIs and objectively rank

themselves against others in the country.

・Water utilities must supply safe water every day, and

conduct preventive maintenance to minimize hazards and

to prevent accidents and failures. To improve the seismic

resistance of water facilities is essential in Japan. Our

equation to predict earthquake damage to water pipelines

will contribute to this goal.

・We will next update the equation to reflect the damage

from the 2011 off the Pacific coast of Tohoku Earthquake.

25

Damage to Drinking Water System

by Off the Pacific coast of Tohoku

earthquake

27

Date and Time: 11 March 2011 14:46 JST (05:46 UTC)

Magnitude: 9.0 (interim value; the largest earthquake recorded in Japan)

Hypocenter: N38.1, E142.9 (130km ESE off Oshika Peninsula) Depth 24km

(interim value)

Mechanism: Reverse fault type with WNW-ESE compressional axis (by CMT

analysis) Earthquake Early

Warning: Issued 8.6 seconds after the detection of the first P-wave at the

nearest seismic station

JMA Seismic Intensity:

7 (Max) Kurihara City of Miyagi Prefecture

6+ 28 cities and towns (including Wakuya Town, Tome City, Osaki City, Natori City) in Miyagi, Fukushima, Ibaraki, and Tochigi Prefectures

6- or weaker Observed nationwide from Hokkaido to Kyushu

(Source)http://www.jma.go.jp/jma/en/2011_Earthquake.html

Summary of Off the Pacific coast of Tohoku

28 （Source)http://www.jishin.go.jp/main/oshirase/201103111446sanriku-oki.gif

←Hypocenter

JMA Seismic Intensity of Off the Pacific coast of Tohoku

←Hypocenter

Upper

Lower

Upper

Lower

(Note) JMA : Japan Meteorological Agency

JMA Seismic Intensity

29

Major Pattern of Damage to Drinking Water

Systems by Off the Pacific coast of Tohoku

☑Earthquake damage only (Inland area)

☑ Damage due to both earthquake and tsunami

(Northeastern coast area)

☑ Damage due to liquefaction (Reclaimed land)

☑ Adverse effect by the Fukushima No 1 nuclear

power plant accident

30

Water Outage by Off the Pacific coast of Tohoku

and Restoration of Water Supply

（Source)http://www.mhlw.go.jp/english/topics/2011eq/dl/damage_situation_110511.pdf

The number of households with interrupted water supply

Recovery rate

31

Typical Cases of Damage to

Drinking Water Systems

32

Damage due to earthquake to PC distribution reservoir in

Ichinoseki city

33

Damage due to earthquake to

φ2400 pipeline in Miyagi prefecture

34

Damage due to earthquake and liquefaction to

WPP in Ishinomaki District Water Supply Authority

35

The surrounding area of this facility subsided

because of liquefaction.

36

Part of the concrete wall cracked due to the quake.

37

A sedimentation basin was disabled because of crack

on the bottom.

38

The Joint part of the stainless pipe was deformed.

39

The floor of pumping station was damaged.

40

Damage due to Tsunami to Takekoma Treatment Plant of Rikuzentakada City

Note : The water source of Takekoma TP is shallow wells which were possibly

salinized.

41

Damage to No.2 Sukedukuri Intake Facility in Minamisanriku Town

Note : The water source of No.2 Sukedukuri Intake facility is shallow wells

which were possibly salinized.

42

Uplifted sewer manhole in Urayasu City

43

Initiatives by JWRC toward full-recovery of

the affected areas

Support team for water purification facilities

・ Promote the installations of more portable

purification devices by private companies

Water quality investigative team

・ Analyze water quality of shallow wells

⇒ to check availability as water source

Thank you for your attention

Please visit our website http://www.jwrc-net.or.jp/index.html