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Dynamic Decision Making for Dam and Levee Risk Management Limin Zhang Hong Kong University of Science and Technology Wuhan University, 19 January 2015

Dynamic Decision Making for Dam and Levee Risk Management

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Page 1: Dynamic Decision Making for Dam and Levee Risk Management

Dynamic Decision Making for Dam

and Levee Risk Management

Limin Zhang

Hong Kong University of Science and Technology

Wuhan University, 19 January 2015

Page 2: Dynamic Decision Making for Dam and Levee Risk Management

2

Outline

Background

Dam-break emergency management process

A framework for dynamic decision making

Dynamic human risk analysis

Dynamic decision making for mitigating the risks of

Tangjiashan Landslide Dam

Summary

Page 3: Dynamic Decision Making for Dam and Levee Risk Management

3

Five major perils (Swiss Re 2013)

Page 4: Dynamic Decision Making for Dam and Levee Risk Management

4

The Pearl River Delta,

including Hong Kong,

Shenzhen, Macau and

Guangzhou, is home to

more than 42 million

people. Situated in one of

the world’s most disaster-

prone regions, floods and

typhoons put more people

at risk than in any other

metropolitan area in the

world.

It is the number one

metropolitan area for storm

surge, with 5.3 million

people affected, the third-

highest for cyclonic wind

damage (17.2 million), and

the fifth riskiest city for river

floods.

Page 5: Dynamic Decision Making for Dam and Levee Risk Management

> 5 m

< 1 m

1–3 m

1–3 m

3–5 m

3–5 m

3–5 m

Flood arrival time and inundation depths –

Pearl River Delta (Breaching at 15.5 m level)

5

Instant

6 – 60 hours

> 60 hours

Page 6: Dynamic Decision Making for Dam and Levee Risk Management

6Banqiao and Shimantan Dam in Henan Province, China,

failed in 1975 and killed more than 26,000 people

Levee failures in New Orleans during the

August 2005 Hurricane Katrina. Death toll:

1,464

Typhoon Haiyan made its landfall in the Philippines on 8 Nov.

2013. Fatalities: 6,340; Damage US$2.86 billion.

Page 7: Dynamic Decision Making for Dam and Levee Risk Management

21 stations

Safety of cascading hydropower systems in China under extreme loading conditions

7

Xiluodu Concrete Gravity Arch Dam, 13860 MW, H = 285.5 m, V = 128x108 m3

Xiangjiaba Concrete Gravity Dam, 7750 MW, H = 162 m, V = 51.6x108 m3

Page 8: Dynamic Decision Making for Dam and Levee Risk Management

8

Tangjiashan

Landslide Dam

Tangjiashan Landslide Dam. Height = 82 m, lake

volume = 316 million m3

(Xinhua News, 2008)

2014年8月3日鲁甸红石岩堰塞湖.

国家防总前方工作组调度堰塞湖上游的德泽水库关闸拦蓄减少入湖水量,缓解堰塞湖水位上涨压力,已拦蓄近5000万立方米。同时,调度堰塞湖下游天花板和黄角树电站预泄腾空库容近1亿立方米,为后期蓄滞堰塞湖下泄洪水做好准备。鲁甸、会泽、巧家、昭阳等4县(区)共疏散转移堰塞湖上下游受威胁群众13044人,其中堰塞湖上游3491人、下游9553人。

2014年08月12, 新华网

Page 9: Dynamic Decision Making for Dam and Levee Risk Management

What is the dam-failure probability?

When will the dam fail?

How large will the flood be?

Who will be affected?

Scientific based flood risk management

How severe are the consequences?

When to evacuate the PAR?

How does monitoring information help the

decision making?

Page 10: Dynamic Decision Making for Dam and Levee Risk Management

10

Outline

Background

Dam-break emergency management process

A framework for dynamic decision making

Dynamic human risk analysis

Dynamic decision making for mitigating the risks of

Tangjiashan Landslide Dam

Summary

Page 11: Dynamic Decision Making for Dam and Levee Risk Management

Emergency management of dam breaks in space

11

Dam-breaching emergency management

Page 12: Dynamic Decision Making for Dam and Levee Risk Management

12

Formation and

development

of dam

breaching (Hanson 2005)

Initia

tion p

hase

Develo

pm

ent p

hase

Failure by

overtopping

Page 13: Dynamic Decision Making for Dam and Levee Risk Management

13Xu and Zhang, 2009

Failure by piping

(b2)(b2)

33

33--44

(a2)(a2)

44

坍塌坍塌

(b3)(b3)

55

55--66

(a3)(a3)

66

Initia

tion p

hase

Develo

pm

ent p

hase

Collapse

McCook, 2007

Page 14: Dynamic Decision Making for Dam and Levee Risk Management

Dam-breaching emergency management

14

Time for issuing evacuation warning (tw)

Water level reaching dam crest

The breach develops to the upstream slope

The flood first arrives the area downstream (tf)

The peak of the flood or the moment that the flood may pose obvious threats to people

Breaching end

Breaching

development time

Flood rise time

(Rt)Breaching

formation time

Warning lead time or lead time Flood routing time

Warning time (Wt)

Emergency management of dam breaks in time

Breaching

formation timeBreaching

development time

Flood rise

time (Rt)

Page 15: Dynamic Decision Making for Dam and Levee Risk Management

15

Evacuation process

Dissemination

of warning

Receipt of

warning

Flood

arrivalRemovalDam-break

signs

Time

Population

Phase 1 Phase 2 Phase 3 Phase 4 After occurence

Death

Warning

Flight

Hydrological

forecasting,

risk

assessment

and decision

making

ResponseEvacuation

Sheltering

PAR

Demand time Flood rise time

Warning

transmitting

time

Response

timeEvacuation

time

Page 17: Dynamic Decision Making for Dam and Levee Risk Management

17

I-45 northbound north of Houston, 21 Sept. 2005. Photo: Shimoda

Thousands of hurricane Katrina survivors from New Orleans are bussed to refuge at a Red Cross shelter in the Houston Astrodome .FEMA photo/Andrea Booher Houston,TX.,9/1/2005

Page 18: Dynamic Decision Making for Dam and Levee Risk Management

Formulating the evacuation process

Probability of successful evacuation

18

PDF

TL, T

FT TF

Probability of successful evacuation

Pf = P(T

F < T

L)Warning time

+ flood rise

time, TL

Demand time, TF

L

Page 19: Dynamic Decision Making for Dam and Levee Risk Management

Human vulnerability in flood

1919

Abt (1989)

Page 20: Dynamic Decision Making for Dam and Levee Risk Management

20

Outline

Background

Dam-break emergency management process

A framework for dynamic decision making

Dynamic human risk analysis

Dynamic decision making for mitigating the risks of

Tangjiashan Landslide Dam

Summary

Page 21: Dynamic Decision Making for Dam and Levee Risk Management

21

Decision making – decision tree

Flood (P1)

No flood (1-P1)

Evacuation

costs

Flood

damages

0 D1

0

C1 d1

(d1<D1)

0

Oi2: Evacuation

Oi1: No evacuation

Oτ2: Evacuation

Oτ1: No evacuation

C2

(C2>C1)

d2

(d2<d1)

0

ti tτ tp

Delayed moment of

decision-making Moment of initiation

decision-making

t

0

C2

(C2>C1)

C1

Loss

of life

L1

0

l1

(l1<L1)

0

l2

(l2<l1)

0

Predicted moment of

flood

Flood (P2)

No flood (1-P2)

Flood (P1)

No flood (1-P1)

(Frieser, 2004)

The time effect is not sufficiently involved in flood time, failure

probability and flood consequences.

Page 22: Dynamic Decision Making for Dam and Levee Risk Management

22

Dynamic decision framework

Proposed decision criteria

• If top ≤ t0, evacuate the population at risk (PAR) immediately;

• If t0 < top < tend, evacuate the PAR at top;

• If top ≥ tend, no evacuation is needed;

• If top is much larger than t0, the decision may be delayed for more information.

Flo

od

co

nse

qu

en

ce

s

Time of evacuation warning

Total loss

Loss of life

Flood damage

Evacuation costs

Optimal point

topt0 tend

Page 23: Dynamic Decision Making for Dam and Levee Risk Management

23

Dynamic decision framework

f(t)

tt0 tend

Da

m fa

ilure

pro

ba

bili

ty

tw

Issue

warning

dt

tf

Possible

flood

Warning time

( )fP f t dt

0

( ) ( ) ( ) [ ( ) ( ) ( )] ( )t t t t

t

E L L t f t dt C W D W L W f t dt

The expected total losses

[ ( )] [ ( ) ( ) ( )] ( )t t tE L t C W D W L W f t dt

Page 24: Dynamic Decision Making for Dam and Levee Risk Management

24

Dynamic decision framework

Discrete probability time series

P(t)

t

Issue

evacuation

warning

tw Warning timePre-warning After floodtf

Possible

flood

tendt0

0 0

( ) ( ) ( ) [ ( ) ( ) ( )] ( )t j j t t t j

j j

E L L t P t C W D W L W P t

Page 25: Dynamic Decision Making for Dam and Levee Risk Management

25

Flood consequences

Evacuation cost• Initiation cost:

• GDP interruption:

( 3)i eva tC cP PAR W

( )( 4)365

PGDP t

GDPC PAR W

Flood damage (moveable properties)• Moveable properties:

• Immoveable properties (e.g. building damage) cannot

be reduced by evacuation

(1 )(1 )( )eva safe pD P P PAR M

Monetized loss of life

( )L pV GDP L

( )L LM V LOL

Predicted by

HURAM as

functions of

warning time

613,745 75 1.03 10 RMB

(Mianyang Bureau of Statistics, 2008)

(Frieser, 2004)

(Jonkman, 2007)

Page 26: Dynamic Decision Making for Dam and Levee Risk Management

26

Outline

Background

Dam-break emergency management process

A framework for dynamic decision making

Dynamic human risk analysis

Dynamic decision making for mitigating the risks of

Tangjiashan Landslide Dam

Summary

Page 27: Dynamic Decision Making for Dam and Levee Risk Management

27

Human risk analysis models

Empirical models: Lack of physical meaning

Physical models: Without studying the human vulnerability

Compromised models: Need considering inter-relationships among parameters

(Jonkman, 2007)

Page 28: Dynamic Decision Making for Dam and Levee Risk Management

28

Factors influencing loss of life:

Bayesian network

Evacuation distance

Time of a day

Distance to dam site

Building story number

Dam breaching duration

Water depth

Flow velocity

Building type

Warning time

Flood rise time

Building damage

Evacuation Sheltering

inside buildings

Flood severity

Loss of life

4 components (sub-networks)

15 nodes (parameters)

23 arcs/links (inter-relationships)

Page 29: Dynamic Decision Making for Dam and Levee Risk Management

29

Quantification of evacuation component

Wt + Rt > Tt + St + Et

Uniform distributions Weibull distributions

Monte Carlo simulation

Available time Demand time

Page 30: Dynamic Decision Making for Dam and Levee Risk Management

30

Sheltering and flood severity

(RESCDAM 2000)

Building damage• Slight damage: inundated

• Partial damage: damage on windows, doors and furniture

• Major damage: damage on structure

Flood severity

Page 31: Dynamic Decision Making for Dam and Levee Risk Management

31

Quantifying the loss of life

2

ln( ) 1.649( ) ( )

0.562

0.643

D

hF h

R

2

ln( ) 3.376( ) ( )

1.188

0.637

D

hF h

R

Low flood severity

Medium flood severity

0

0.01

0.02

0.03

0.04

0.05

0 1 2 3 4 5

Water depth (m)

Fa

tality

ra

tio

Recorded data

Simulated curve

0

0.1

0.2

0.3

0.4

0.5

0 1 2 3 4 5 6

Water depth (m)

Fa

tality

ra

te

Recorded data

Simulated curve

Page 32: Dynamic Decision Making for Dam and Levee Risk Management

32

The prior probabilities

(Using Hugin Lite 7.2, 2009)

Page 33: Dynamic Decision Making for Dam and Levee Risk Management

Calculated fatality rates-general conditions

33

Flood

severity

Warning

time

(Minute)

Flood

severity

understanding

Fatality rate

Graham’s model (1999) This model

Suggested

value

Suggested

range

High No warning N/A 0.75 0.30 – 1.0 0.7707

15-60 Vague Use the values shown above

and apply to the number of

people who remain in the

dam failure floodplain after

warnings are issued.

0.4195

Precise

More than

60

Vague 0.0794

Precise

Medium No warning N/A 0.15 0.03 - 0.35 0.1071

15-60 Vague 0.04 0.01 - 0.08 0.0593

Precise 0.02 0.005 - 0.04

More than

60

Vague 0.03 0.005 - 0.06 0.0117

Precise 0.01 0.0 - 0.02

Low No warning N/A 0.01 0.0 - 0.02 0.0079

15-60 Vague 0.007 0.0 - 0.015 0.0045

Precise 0.002 0.0 - 0.004

More than

60

Vague 0.0003 0.0 - 0.0006 0.0009

Precise 0.0002 0.0 - 0.0004

Page 34: Dynamic Decision Making for Dam and Levee Risk Management

34

Predictions of historical cases

(50 historical cases)

1.0E-05

1.0E-04

1.0E-03

1.0E-02

1.0E-01

1.0E+00

1.0E-05 1.0E-04 1.0E-03 1.0E-02 1.0E-01 1.0E+00

Recorded fatality rate

Pre

dic

ted

fa

tality

ra

te

The present model

Graham's model, 1999

D&M model, 1993

Page 35: Dynamic Decision Making for Dam and Levee Risk Management

35

Application – Beichuan, Qp = 6500 m3/s

690

670

650

630

610200 400 600 800 1000

Ele

va

tio

n (

m)

Distance (m)

631.13

Bank

RiverResidential area

R1 R2 R4 R5R3

0

R0

R0

0 - 1.5

1.5 - 2

2 - 3

3 – 4.5

4.5 - 6

Residential

areaWater

depth (m)

0

R1

R2

R3

R4

R5

Buildings625

615.8

R6

6 - 6.13R6

Evacuation

distance (m)

0

0-75

75-100

100-150

150-225

225-300

300-306.5

Time of a

day

Breaching

time

Distance to

dam site

Water flow

velocity

Building type Building

story number

12:00-13:00 14 hours 3.5 km 1.14 m/s Brick 3

(With HEC-RAS)

Page 36: Dynamic Decision Making for Dam and Levee Risk Management

36

Application – Subarea R6

(Using Hugin Lite 7.2, 2009)

Page 37: Dynamic Decision Making for Dam and Levee Risk Management

37

Ranking important factors - Subarea R6

0.00

0.05

0.10

0.15

0.20

Eva Tod Fs Sib Wt D Rt Dbt Bsn V Bt Bd Dtd Ed

Parameters

Co

nd

itio

na

l p

rob

ab

ility o

f lo

ss o

f life

`

Eva = evacuation

Tod = time of a day

Fs = flood severity

Sib = sheltering inside building

Wt = warning time

D = water depth

Rt = flood rise time

Dtd = distance to dam site

Bsn = building story number

V = water flow velocity

Bt = building type

Bd = building damage

Dbt = dam breaching duration

Ed = evacuation distance

Water depth: 6-6.13 m

Evacuation

Time of a day

Warning time

Flood severity Water depth Building damage

Page 38: Dynamic Decision Making for Dam and Levee Risk Management

38

Outline

Background

Dam-break emergency management process

A framework for dynamic decision making

Dynamic human risk analysis

Dynamic decision making for mitigating the risks of

Tangjiashan Landslide Dam

Summary

Page 39: Dynamic Decision Making for Dam and Levee Risk Management

39

Application of Tangjiashan Landslide Dam

Dam site

Beichuan Town

Tongkou Town

Hanzeng

Town

Qinglian Town

Longfeng Town

Mianyang City

Shima Town

Fu R

iver

Fu R

iver

Tongko

u R

iver

Jian River

Jian river

To solve the problems:

• Is it necessary to evacuate the population at risk (PAR)?

• When is the optimal time to evacuate the PAR?

• What is the minimum total consequences?

• How does new monitoring information help the

decision making?

Page 40: Dynamic Decision Making for Dam and Levee Risk Management

40

Breaching model of landslide dams

Bt

Bb

Hb

Hd

Hd = dam height

Hb = breach depth

Bt = breach top width

Bb = breach bottom width

River

Landslide

Landslide dam

River

Dam width

Dam

le

ngth

Control variables

• Dam height (Hd)

• Lake volume (Vl)

• Dam width (Wd)

• Dam volume (Vd)

• Dam Erodibility (E)

Breaching parameters

• Peak outflow rate (Qp)

• Breach depth (Hb)

• Breach top width (Wt)

• Breach bottom width (Wb)

• Breaching time (Tb)

Page 41: Dynamic Decision Making for Dam and Levee Risk Management

41

Dynamic decision framework

Dam failure probability

DamReservoir

t

H

Water level

Hcr

Ht

t

V

Vcr

Vt

Lake volume

( ) 1 ( )t cr t crP V V P V V

Overtopping failure t cr t crH H V V

( )t t t t oV V Q Q t

Page 42: Dynamic Decision Making for Dam and Levee Risk Management

42

Dam failure probability as a time series

0

50

100

150

200

250

300

350

2008/5/15 2008/5/20 2008/5/25 2008/5/30 2008/6/4 2008/6/9 2008/6/14

Time

La

ke

vo

lum

e (

millio

n m

3)

Records

Predictions

Lower bound of 95% confidence interval

Upper bound of 95% confidence interval

Vcr = 316 million m3

0

0.2

0.4

0.6

0.8

1

2008/6/5 2008/6/10 2008/6/15 2008/6/20 2008/6/25

Time

Da

m fa

ilu

re p

rob

ab

ility

Cumulative probability

Discrete probability

( ) 1 ( ) 1 ( )cr Vtt cr t cr

Vt

V MP V V P V V

1 20.463 0.181t t t tQ Q Q a

Autoregressive model, AR(2):

Page 43: Dynamic Decision Making for Dam and Levee Risk Management

43

Empirical models for breach parameters

Full-parameter model

(5 control variables)

Simplified model

(3 control variables )

Breaching

parameter

Breach bottom width

Breach top width

Breach depth

Peak outflow rate

Failure time

1/3-1.417 -0.265 -0.471

1/ 2 5/ 2

1/31.569

( ) ( ) ( )

( )

p d d d

d c d d

al

d

Q H H V

g H H W H

Ve

H

1/30.882 -0.041 -0.099

1/30.139

( ) ( ) ( )

( )

b d d d

c c d d

al

d

H H H V

H H W H

Ve

H

1/30.752 0.315 -0.243

1/30.682

( ) ( ) ( )

( )

t d d d

c c d d

al

d

W H H V

H H W H

Ve

H

1/3

1/3

0.004( ) 0.050( ) 0.044 ( )

0.088( )

b d d d

d c d d

l

d

W H H V

H H W H

Va

H

1/30.262 -0.024 -0.103

1/30.705

( ) ( ) ( )

( )

b d d d

r c d d

al

d

T H H V

T H W H

Ve

H

1/3-1.371 1.536

1/ 2 5/ 2( ) ( )

p ad l

d c d

Q H Ve

g H H H

1/30.923 0.118( ) ( ) ab d l

c c d

H H Ve

H H H

1/30.911 0.271( ) ( ) at d l

c c d

W H Ve

H H H

1/3

0.003( ) 0.070( )b d l

d c d

W H Va

H H H

1/30.293 0.723( ) ( ) ab d l

r c d

T H Ve

T H H

Page 44: Dynamic Decision Making for Dam and Levee Risk Management

44

Physically based modeling of dam breaching

fu f f

L0

Bc0

ff f f

Chang and Zhang 2010

F(failure | overtopping)

= f (e, Cu, PI, P, S, Rh)

Failure by overtopping

Page 45: Dynamic Decision Making for Dam and Levee Risk Management

4545

Time line of the Tangjiashan event

12 May 15 23 1 June 7

The dam formed

The dam geometric parameters were identified

The geological conditions of the dam were obtained

A division channel was constructed

The water level reached the division channel

6:00

Breaching started

Breaching finished

Stage 1 Stage 2 Stage 3 Timeline

20:00

10 June

Stage 1 Stage 3Stage 2

Jian River

Stage 1

600

700

800

900

0 100 200 300 400 500 600 700 800 900

600

700

800

900

1000

1100

Gravelly soil

Strongly weathering cataclasite

Weakly weathering cataclasite Breach

Gravels with soil

Original

slope before

slide

752.2

m

Ele

va

tio

n (

m)

Distance (m)

Ele

va

tio

n (

m)

Stage 2 Stage 3

Page 46: Dynamic Decision Making for Dam and Levee Risk Management

4646

Time line of the Tangjiashan event

Geometric parameters of the dam

Dam height 82 m

Dam width 802 m

Dam length 611 m

Dam volume 20.4 million m3

Lake capacity 316 million m3

12 May 15 23 1 June 7

The dam formed

The dam geometric parameters were identified

The geological conditions of the dam were obtained

A division channel was constructed

The water level reached the division channel

6:00

Breaching started

Breaching finished

Stage 1 Stage 2 Stage 3 Timeline

20:00

10 June

Stage 1 – Empirical models for breaching simulation

Stage 1 Stage 3Stage 2

Page 47: Dynamic Decision Making for Dam and Levee Risk Management

4747

Time line of the Tangjiashan event

12 May 15 23 1 June 7

The dam formed

The dam geometric parameters were identified

The geological conditions of the dam were obtained

A division channel was constructed

The water level reached the division channel

6:00

Breaching started

Breaching finished

Stage 1 Stage 2 Stage 3 Timeline

20:00

10 June

200 400 600 800 1000 1200 14000600

700

650

750

800

740.4m Gravelly soil

Strongly weathered cataclasite

Weakly weathered cataclasite

Bedrock

752.2 m

Ele

vati

on (

m)

Distance (m)

Stage 2 – DABA (physical) model (Chang and Zhang 2010)

High erodibility

Stage 1 Stage 3Stage 2

600

700

800

900

0 100 200 300 400 500 600 700 800 900

600

700

800

900

1000

1100

Gravelly soil

Strongly weathering cataclasite

Weakly weathering cataclasite Breach

Gravels with soil

Original

slope before

slide

752.2

m

Ele

vatio

n (

m)

Distance (m)

Ele

vatio

n (

m)

Page 48: Dynamic Decision Making for Dam and Levee Risk Management

48

Time line of the Tangjiashan event

Parameters of the division channel

Channel depth 12 m

Channel width 25 m

Channel length 611 m

Excavation soil volume 20.4 million m3

Lake capacity after the construction of the channel

247 million m3

12 May 15 23 1 June 7

The dam formed

The dam geometric parameters were identified

The geological conditions of the dam were obtained

A division channel was constructed

The water level reached the division channel

6:00

Breaching started

Breaching finished

Stage 1 Stage 2 Stage 3 Timeline

20:00

10 June

Wt

Wb

Hb

Hd

Hd = dam height

Hb = spillway depth

Wt = spillway width

Wb = spillway width

Stage 3 – DABA (physical) model (Chang and Zhang 2010)

Stage 1 Stage 3Stage 2

Page 49: Dynamic Decision Making for Dam and Levee Risk Management

49

0

0.01

0.02

0.03

2008/6/3 0:00 2008/6/8 0:00 2008/6/13 0:00 2008/6/18 0:00 2008/6/23 0:00

Time

Dis

cre

te d

am

-bre

ak p

rob

ab

ility

Prediction of dam failure probability

Dam-failure probabilities as a time series

Stage 3

Stage 2Stage 1

Page 50: Dynamic Decision Making for Dam and Levee Risk Management

50

Uncertainty of breaching parameters

Scenario Low erodibility Medium erodibility High erodibility

Number of cases 15 31 6

Probability 0.116 0.596 0.288

Qp in stage 1 2,160 7,100 35,610

Stage 1 (empirical model)

Stages 2 and 3 (physical model)

m.5 m.5m1.5 m1.5

S1

S2

S3

S4

S5

Scenario S1 S2 S3 S4 S5

Probability 0.067 0.242 0.382 0.242 0.067

Quantile m1.83 m.89 m m.89 m1.83

Qp in stage 2 5,570 9,120 14,700 25,180 39,090

Qp in stage 3 2,450 4,050 6,540 10,420 17,260

m: predicted by DABA

: obtained by statistics

Page 51: Dynamic Decision Making for Dam and Levee Risk Management

51

0

10000

20000

30000

40000

0 10 20 30 40 50 60

Time (hour)

Pe

ak o

utflo

w r

ate

(m

3/s

)

High erodibility (0.228)

Medium erodibility (0.596)

Low erodibility (0.116)

Stage 1

0

10000

20000

30000

40000

0 10 20 30 40 50 60

Time (hour)

Pe

ak o

utflo

w r

ate

(m

3/s

)

High erodibility (0.228)

Medium erodibility (0.596)

Low erodibility (0.116)

Stage 1

Floods in the three stages

Stage 1

0

10000

20000

30000

40000

0 10 20 30Time (hour)

Pe

ak o

utflo

w r

ate

(m

3/s

)

Scenario 5

Scenario 4

Scenario 3

Scenario 2

Scenario 1

Scenario 5 (0.067)

Scenario 4 (0.242)

Scenario 3 (0.382)

Scenario 2 (0.242)

Scenario 1 (0.067)

Stage 2

Stage 1

0

10000

20000

30000

40000

0 10 20 30Time (hour)

Pe

ak o

utflo

w r

ate

(m

3/s

)

Scenario 5

Scenario 4

Scenario 3

Scenario 2

Scenario 1

Scenario 5 (0.067)

Scenario 4 (0.242)

Scenario 3 (0.382)

Scenario 2 (0.242)

Scenario 1 (0.067)

Stage 2

0

5000

10000

15000

20000

0 10 20 30Time (hour)

Pe

ak o

utflo

w r

ate

(m

3/s

)

Scenario 5 (0.067)

Scenario 4 (0.242)

Scenario 3 (0.382)

Scenario 2 (0.242)

Scenario 1 (0.067)

Stage 3

0

5000

10000

15000

20000

0 10 20 30Time (hour)

Pe

ak o

utflo

w r

ate

(m

3/s

)

Scenario 5 (0.067)

Scenario 4 (0.242)

Scenario 3 (0.382)

Scenario 2 (0.242)

Scenario 1 (0.067)

Stage 3

Page 52: Dynamic Decision Making for Dam and Levee Risk Management

52

Evaluation of consequences

(With VBA in

Excel)

Monetized loss of life

Evacuation cost

Flood damage

Warning time

Page 53: Dynamic Decision Making for Dam and Levee Risk Management

53

Decision making – Beichuan

0

100

200

300

2008/6/14 0:00 2008/6/15 0:00 2008/6/16 0:00 2008/6/17 0:00 2008/6/18 0:00 2008/6/19 0:00

Time

Flo

od

co

nse

qu

en

ce

s (

RM

B m

illio

n)` Evacuation cost

Flood damage

Monetized loss of life

Total consequence

Optimum time to evacuate

the PAR: 16 June 08:00

with a total consequence

of RMB41.93 million

Stage 1

0

100

200

300

2008/6/14 0:00 2008/6/15 0:00 2008/6/16 0:00 2008/6/17 0:00 2008/6/18 0:00 2008/6/19 0:00

Time

Flo

od

co

nse

qu

en

ce

s (

RM

B M

illio

n)` Evacuation cost

Flood damage

Monetized loss of life

Total consequence

Optimum time to evacuate

the PAR: 15 June 21:00

with a total consequence of

RMB41.60 million

Stage 2

0

100

200

300

2008/6/5 0:00 2008/6/6 0:00 2008/6/7 0:00 2008/6/8 0:00 2008/6/9 0:00 2008/6/10 0:00

TimeF

loo

d c

on

se

qu

en

ce

s (

RM

B m

illio

n)` Evacuation cost

Flood damage

Monetized loss of life

Total consequence

Optimum time to evacuate

the PAR: 7 June 00:00

with a total consequence of

RMB36.20 million

Stage 3

All people (0.03 million)

were evacuated by 1 June

Page 54: Dynamic Decision Making for Dam and Levee Risk Management

54

Decision making – Mianyang

0

200

400

600

800

2008/6/15 0:00 2008/6/17 0:00 2008/6/19 0:00 2008/6/21 0:00 2008/6/23 0:00

Time

Flo

od

co

nse

qu

en

ce

s (

RM

B m

illio

n)`

Optimum time to evacuate

the PAR: 19 June 10:00

with a total consequence of

RMB370.10 million

Stage 1

Total losses

Monetized loss of life

Evacuation costs

Flood damage

0

200

400

600

800

2008/6/15 0:00 2008/6/17 0:00 2008/6/19 0:00 2008/6/21 0:00 2008/6/23 0:00

Time

Flo

od

co

nse

qu

en

ce

s (

Millio

n R

MB

)`

Optimum time to evacuate

the PAR: 18 June 18:00

with a total consequence of

RMB380.88 million

Stage 2

Total losses

Monetized loss of life

Evacuation costs

Flood damage

No flooding is

predicted in Stage 3

in Miangyang City

0.2 million people were evacuated by 1 June

Page 55: Dynamic Decision Making for Dam and Levee Risk Management

55

Summary

Understanding the dam/levee break emergency management –

probabilistic formulation of the process

Framework of dynamic decision making for dam/levee risk

management – basis for scientific decision; – the dam failure

probability as a time series and the flood consequences as functions

of the warning time.

Consequences of dam-break floods - evacuation costs, flood damage

and loss of life.

Rapid evaluation of human risk - HURAM, a model for simulating

human-flood interactions using Bayesian networks.

The decision making - a process depending on information available.

Dynamic decision making for the emergency management of

Tangjiashan Landslide Dam - three stages with different levels of

hydrological, geological and social-economic information.

Page 56: Dynamic Decision Making for Dam and Levee Risk Management

56

Thanks for your attention