Sustainable Infrastructure Jeanne Huang Ph.D, P. Eng

School of Civil Engineering Tianjin University

Recent Climate Change Research inTianjin and its Implication for

Tianjin University

1 、 Introduction and Urban Flooding

2 、 Research on Urban Precipitation

3 、 Sustainable Infrastructure

4 、 Conclusions

Introduction andUrban Flooding

1

Tianjin University

IntroductionFlooding death toll in China （ 1950-2010 ）

5000

10000

15000

20000

45000

40000

35000

30000

25000

8571

4091 5181

The 1931 big floods in the Yangtze & Huai River basins, 51 million people affected and 400,000 died4349 3909

42,447 people died during the big flood of 1954F

lood

dea

th t

oll

1950

1952

1954

1956

1958

1960

1962

1964

1966

1968

1970

1972

1974

1976

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

2010

0

50

100

150

200

250

300

350

400

450

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

Year

Dir

ect

eco

no

mic

loss

es

(bill

ion

RM

B

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

Re

lativ

e lo

sse

s (%

)

Flood economic losses in China(1990-2010 )

2.39 0.64

5Data Source: Bulletin of Flood and Drought Disasters in China (2010)

• In 2010, only 35.3% of the flood losses came from the damages of agriculture, forestry, animal husbandry and

• Especially, more than 250 cities at or above the countylevel were inundated in 2010, and most of them werecaused by the local rainstorms.

fishery. The other nearly 2/3 of the total losses was composed of the damages of industry, traffic and transportation, and the damages of infrastructures.

0

1000

2000

3000

4000

5000

6000

7000

8000

Year

Death toll caused by flood related hazards in China (1980-2010)

43493909

1454

42254150

The dead and missing in Zhouqu debris flow event: 1765=1510+255

Dead: 3222Missing: 1003Total: 4225

6Data Source: Bulletin of Flood and Drought Disasters in China (2010)

deat

h to

ll

1980

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

Death toll caused by flash flood, landslideand debris flow in China (1991-2010)

5000

4500

4000

3500

3000

2500

2000

1500

1000

500

0

Year

1.00

0.90

0.80

0.70

0.60

0.50

0.40

0.30

0.20

0.10

0.00

dead

r a t e

Dead: 2824 (not including missing)

7Data Source: Bulletin of Flood and Drought Disasters in China (2010)

Zhouqu: 1765

199

11

992

199

31

994

199

51

996

199

71

998

199

92

000

200

12

002

200

32

004

200

52

006

200

7

200

82

009

201

0

deat

h to

ll

Causing Analysis (1)• Climate fluctuation

Annual average precipitation in China from 2000 to 2010Data Source: China Water Resources Bulletin (2000 - 2010), MWR.

8

Causing Analysis (2)• Rapid economic development• Rapid growth of Population• Rapid changes of Land use due to urbanization and

infrastructures construction

0

5000

10000

45000

40000

35000

30000

25000

20000

15000

1960

1963

1966

1969

1972

1975

1978

1981

1984

1987

1990

1993

1996

1999

2002

2005

2008

Year

GD

P

an

d F

ina

nci

al

Re

ven

ue

(B

illio

n R

MB

)

GDP

Financial Revenue

Common features of urbanization

• Urbanization rate rising from 20% to 40%, the UK spent 120 years, France 100 years, Germany 80 years, the USA 40 years, while China took only 22 years.

• During such rapid process, underground infrastructures as drainage system were always being ignored. The governors of cities have to pay more attention to some critical issues such as housing, traffic jam, power supply, water supply, and so on, taking the so called policy “on the ground priority”.

10

Year 1952 1970 1980 1990 2000 2003 2008

Urban population（ million ）

39 93 191 302 461 520 607

percentage（ % ）

8.30 11.2 19.39 26.41 36.09 40.5 45.7

A series of large cities suffered by severe flood in recent years: Nanjing, Beijing, Shanghai, Wuhan, Gangzhou, Fuzhou,Shenzhen, Xian, Hangzhou, Jinan,Zhenzhou, Chongqing, Chengdu…

Urban Floods Damages Increasedin China

Flash flood occurred in Jinan in July 18, 2007

Intra-urban flooding occurred in Beijing in July 10, 2004Fluvial flooding,

Wuzhou, Guangxi, June 22, 2005

Guangzhou, May 7,2010

Wuhan June 182011

On July 21, 2012, Beijing was struck byheavy rainstorm again.

The day is as dark as the night. Severe traffic jams occurred, and large number of people plugging on the way.

Max. rainfall: 460mm ; and 128.9mm/hr Ave. rainfall: 63 mm;

句學

How the challenges can be addressed

Developing stage

• Rapid process of urbanization• Weak flood control and drainage system• The gap between rich and poor• Increasing uncertainties in global warming• ……

How to keep or rehabilitatethe existed balance?

How to cope with the challenges coming in the future?

High level of management, with strong economic and technical capacities

Sustainable development stage

How to enhance or create new balance step by step to meet the demands of rapid and smooth development?

？ ？

C D

Where can we find some other weights?

scale

How to restore the balance?

How to meet the basic needs of survival? Lower demands in security

Flood control system developed in a whacky circleLower technical ability Low level of urbanization

Undeveloped stage

Coping Strategies (1)

2000

2003

2006

2007

• The investment has been increased several fold in enhancingflood control system by comprehensive measures.• Formed a new thinking to promote a harmonious

relationship between man and nature in water governance for the sustainable development since.

• To promote the “two shifts” in flood control and drought relief affairs, i.e. shifting “from flood control to flood Management” and “from simplex drought-fighting to comprehensive drought management”.

• A series of measures have been taken to enhance theemergency response system and capacity building.

• Taking the people's livelihood related water issues as a moreprominent and top-priority tasks.

15

1998

Coping Strategies (2)

• In 2009, 200 million Yuan RMB was invested in the development of non-structural measures for early warning of flash floods in 103 pilot counties, which increased to 500 in 2010. The number is expected to increase up to 1,836 in 3 years.

• In the beginning of 2011, the No 1 Document issued by the Central Government aimed to accelerate the reform and development of water governance.

16

Coping Strategies (3)• The input for water security and sustainable

utilization will be multiplied by the governments at all levels, i.e. to invest 400 billion Yuan RMB on average per year in the 12th and 13th Five-year Plans (2011-2020).

• The National Master Plan for the Integrated Management of Medium and Small Rivers, the Reinforcement for Unsafe Reservoirs, and Prevention and Comprehensive Treatment of Flash Flood and Mountain Disasters have been discussed and approved by the State Council in early April 2011.

City

Tianjin University

Recent ClimateResearch for Tianjin

City

2

Tianjin

Tianjin is a dual-core city, with its main urban area (including the old city) located along the Hai River, which connects to the Yellow and Yangtze Rivers via the Grand Canal.

Trend in Average Temperature (The City of Tianjin)

Month S VAR Z ConfidenceLevel

Trend

Jan 260 18924.67 1.88 0.9699 Significant Increase

Feb 344 18946.33 2.49 0.9636 Significant Increase

Mar 484 18948 3.51 0.9998 Significant Increase

Apr 584 18930 4.24 1.0000 Significant Increase

May 331 18915.67 2.40 0.9918 Significant Increase

Jun 359 18934 2.60 0.9953 Significant Increase

Jul 194 18882.33 1.40 0.9192 Slight Increase

Aug 149 18911 1.08 0.8599 Slight Increase

Sep 119 18842.67 0.86 0.8051 No

Oct 127 18915.33 0.92 0.8212 No

Nov 54 18931.67 0.39 0.6517 No

Dec 189 18920.67 1.37 0.9147 Slight Increase

Trend in Average Precipitation(The City of Tianjin)

Month Z β Trend

January -0.8983 -0.005 No

February -0.8883 -0.012 No

March -0.6508 -0.021 No

April -0.1656 -0.014 No

May 1.4490 0.301 No

June 1.4632 0.589 No

July -2.0779 -1.331 Significant Decrease

August -2.1344 -1.316 Significant Decrease

September 0.0071 0.002 No

October 0.3871 0.047 No

November -0.4667 -0.030 No

December -0.3137 0.000 No

Trend Analysis for Annual and Seasonal Precipitation Change

Z=1.96 ->confidence level = 95%

Annual

and

Season

Years Z β Trend

Annual 56 -1.2368 -1.620 No

Spring 56 1.1097 0.332 No

Summer 56 -2.0425 -1.657 Significant Decrease

Fall 56 0.3887 -1.477 No

Winter 56 -1.4773 -0.009 No

Seasonal Variation

1960 1970 1980

年份1990 2000

-4

-2

0

2

4

统计量

UF 统计量

k

UB 统计量k0.05 显著水平

1960 1970 1980

年份1990 2000

-4

-2

0

2

4

统计量

UF 统计量k

UB 统计量k

0.05 显著水平

1960 1970 1980

年份1990 2000

-4

-2

0

2

4

统计量

UF 统计量

k

UB 统计量

k

0.05 显著水平

1960 1970 1980

年份1990 2000

-4

-2

0

2

4

统计量

UF 统计量k

UB 统计量k

0.05 显著水平

Spring Summer

Fall Winter

1960 1970 20001980

年份1990

-4

-2

0

2

4

统计量

UF 统计量k

UB 统计量k

0.05 显著水平

1960 1970 1980

年份1990 2000

-4

-2

0

2

4

统计量

UF 统计量

kUB 统计量

k

0.05 显著水平

July August

IDF fitting Methods1

2

3

Rainfall Distribution Study

Area Reduction Factor Study

Design Storm Study

Gumbel

Exponentialdist r ibut ion

General Extreme Value

Pearson I I I

IDF Curve Development

0 5 0 1 0 0 1 5 0 2 0 0

2 . 0

1 . 5

1 . 0

0 . 5

0 . 0

2 . 5

3 . 0旧 2 旧 3 新 2 新 3

Comparing 2 y and 3y return period IDF Curves

Comparison of IDF CurvesIn

tens

ity (m

m/m

in)

Duration (Min)

Comparing 2 y and 3y return period IDF Curves for 6 hrs Rain Event

Comparison of IDF Curves

Return Period Total Depth (mm)

2 3 5 10 20 30 50 100

New 79.5 326.5 106.0 127.4 148.7 161.1 176.5 198.8

Old 53.6 59.7 67.4 77.8 88.2 94.3 102.0 112.5

Huff Rainfall Distribution

Storm 2

雨峰雨峰

雨峰

降雨强度

降雨持续时间

雨峰

D1

D2

D3

Storm 1

Minimum Time ： 12hrs

Threshold ：20mm

Rainfall Event Separation

0 20 40 60

时间累积百分比80 100

0.0

0.8

时段雨量占总雨量的比例

概率水平 10%

0 2040 60

时间累积百分比

80 100

0.0

0.4

时段雨量占总雨量的比例

概率水平50%

0 20 40 60

时间累积百分比80 100

0.0

0 .2

Lest Critical

0.4

时段雨量占总雨量的

比例

Most Critical

Secondary

概率水平 90%

0.4

Rainfall Distribution for Different Time Periods

0 10 20 30

降雨历时 (min)

40 50 600

20

40

60

80

100

降雨量累积百分比

10%20%30%40%50%60%70%80%90%

0 30 60 90

降雨历时 (min)

120 150 1800

20

40

60

80

100

降雨量累积百分比

10%20%30%40%50%60%70%80%90%

0 60 120 180

240

降雨历时(min)

300 360

0

20

40

60

80

100

降雨量累积百分比

10%20%30%40%50%60%70%80%90%

0 120 240 360480

降雨历时 (min)

600 720

0

20

40

60

80

100

降雨量累积百分比

10%20%30%40%50%60%70%80%90%

1hr

3hr

6hr

12hr

July 21, 2012 Storm in Tianjin (observed)

Citywide Average

Downtown Core

Comparison of Design Storm Distribution with July 21, 2012 Storm (Downtown)

10%50%

90%

Comparison of Design Storm Distribution with July 21, 2012 Storm (Citywide)

10%50%

54 Year Samples for Design Storm

30 Year Samples for Design Storm

Area Reduction Study

4 years data in minute from 28 digital rain gauges for 250 km2

Thiessen Method

0 50 100

区域面积150 200

0.0

0.2

0.4

0.6

0.8

1.0

点面折减系数

1hr 3hr 6hr 12hr 24hr

Reduction Rate for City ofTianjin

For shorter period rainfall, the reduction rate drop more steeply

SustainableInfrastructure

3

Tianjin University

Urban Development and Its Changes to the Natural

Water Balance

A Guide Book for BC Stormwater Planning

Change in Hydrology

Rural/Undeveloped

Single Family Residential (large lots)

Single Family Residential (small lots) Mixed Land Use-High

Density

Nature Condition Slight Impact Signification Impact Major Impact

Decreasing Base flows

Increasing Peak flows

Increasing channel Erosions

Rural/Undeveloped

Single Family Residential (large lots)

Single Family Residential (small lots) Mixed Land Use-High

Density

Decreasing Base flows

Increasing Peak flows Increasing

channel Erosions

Increasing Temperature

Natural Condition

Slight Impact Signification Impact

constructed cross-section

Major Impact

Guiding Principles: ADAPT

ADAPT

T

A

P

A

Design for the complete spectrum of rainfall event

Agree that storm water is a resource

Act on a priority basis in at-risk drainage catchments

Test solutions and reduces costs by adaptive management

Plan at four scales– regional,watershed, neighborhood and site

D

Low Impact Development低影响开发

1. Mimic Original Eco system in terms of hydrological aspects2. Decentralized Control Strategy3. Use source control in stead of End Control

Summary of LID Principles

Stormwater:

•Slow it down

•Spread it out

•Soak it in

1. 2007 Dry Year2. Total Precipitation: 634 mm

1. No Surface Runoff up to approx 25 mm2. Removing most contaminants found in parking lot

Conclusions3

Tianjin University

Conclusions

1

2

3

In Urban Area, rainfall is localized, it makes the

flooding issue more severe and give more

pressure for infrastructure

Precipitation is one of very important driven

forces for the change of eco system

Integrated Water Resources Management/LID

might be the solution to restore the original

hydrologic cycle and relief part of the pressure

to our infrastructure

The End