1. Landslides and large dams
David Petley
Wilson Professor Hazard and Risk
Dean of Research and Global Engagement
Durham University, United Kingdom
∂
http://blogs.agu.org/landslideblog/
Google: “landslide blog AGU”

2. Vajont
The key lesson in dams and
landslides
∂
Images from Wikipedia

3. Large landslides and dam projects
• But, some landslides have continued to occur on the flanks
of reservoirs
• Some, but perhaps surprisingly few, have been fatal
• E.g. Qianjinangping landslide, July 2003, 24 fatalities:
∂

4. Clyde Dam, New Zealand:
Successful landslide
management
€580 million (2005 value)
∂

5. Existing large dams
UN large dam database (2012)
∂
Each red dot is a large dam on the UN database.
Existing dams are concentrated in mountain areas, but not in very high
mountains

6. Large dam density
UN large dam database (2012)
∂
Few dams here
Contour map of the density of existing large dams
Existing dams are concentrated in medium but not in very high mountain
areas

7. Distribution of fatality-inducing landslides 2004-2011
∂
Each dot is a landslide that killed one or more people.
Note the focus of landslides in high mountain areas, especially the
Himalayas

8. Large dams and fatality-inducing landslide events
(2004-2011)
∂
The distribution of fatal landslides and large existing dams does not
overlap significantly, especially in the Himalayas
Conclusion: we have mostly built large dams where landslides do not kill
many people (NB China)

9. Large dams completed since 1990
∂
Each dot is a large dam constructed since 1990
Note:
• Increased numbers of dams in China
• Dams starting to be constructed in high mountain areas
There is more dam building now in areas with many landslides

10. Analysis of landslides associated with large dams
• Fatality-inducing landslides between 2003 and 2012 that
have been associated with large dams:
500 deaths in 37 landslide events
∂

11. Date
Country
Location
Deaths
13/07/2003
03/08/2004
23/04/2004
26/04/2005
28/06/2005
07/10/2006
15/12/2007
19/07/2007
20/07/2007
10/08/2007
14/08/2007
07/09/2007
15/12/2007
12/05/2008
20/05/2008
07/06/2008
31/07/2008
11/09/2008
07/05/2009
03/06/2009
23/07/2009
31/07/2009
23/01/2010
14/02/2010
15/06/2010
26/07/2010
31/07/2010
02/08/2010
15/06/2011
18/09/2011
18/09/2011
18/09/2011
28/02/2011
28/06/2012
13/07/2012
30/08/2012
15/05/2012
China
India
China
India
India
China
Vietnam
China
China
China
India
Bhutan
Vietnam
China
Chile
Bhutan
China
Nepal
Tajikistan
Vietnam
China
China
Vietnam
India
China
China
Pakistan
Nepal
China
India
India
India
India
China
China
China
Turkey
Qiangjingping
Tehri Dam, Uttranchal
Majuangou, Shaanxi
Mulliyar, Kerala
Shahpur, Ghatgar
Fangxian C’ty, Hubei
Tuong Duong, Nghe An
Sujiahekou , Yunnan
Guide County, Qinghai
Ya'an City, Sichuan
Dharla, Himachal Pradesh
Chukha dzong
Tuong Duong, Nghe An
Jinhe HEP
San Fernando
Wangkha
Ya'an City, Sichuan
Khare VDC, Dolakha
Rogun
Nam Khoa, Lao Cai
Kangding C’ty, Sichuan
Jinyang C’ty, Sichuan
Ve village, Yen Bai
Kinnaur, Himanchal Pradesh
Kangding county, Sichuan
Gongshan Drung-Nu, Yunnan
Patan, Khyber Pakhtunkhwa
Gaurishankar, Dolakha
Shiyan, Hubei
Salim Payel, Mangan
Teesta HEP, Sikkim
Teesta HEP, Sikkim
Asiganga, Uttarakashi.
Ningnan C’ty, Sichuan
Shuicheng C’ty, Guizhou
Liangshan Yi Sichuan
Kızıltaş, Dereli, Giresun
24
29
4
10
15
6
18
29
8
12
62
2
18
22
1
12
5
1
2
4
54
9
1
8
23
11
3
11
3
10
1
7
4
40
3
24
4
∂
Indicative dam project
NB low certainty
Three Gorges Dam
Tehri Dam
Small scale hydro
Small scale hydro
Ghatghar HEP
Not known
Ban Ve HEP
Sujiahekou HEP
Laxiwa HP Station
Long Tou Shi Dam
Ghanvi HEP
Chuka HEP
Ban Ve HEP
Jinhe HEP
Not known
Tala HP project
Long Tou Shi Dam
Upper Tamakoshi HP
Rogun HEP
Nam Khoa HEP
Changheba HEP
Not known
Nam Toc HEP
Karcham-Wangtoo HEP
Kangding Longtou HEP
Unknown
Patan Hydropower project
Sipirang River HEP
Hubei Shyan Longbeiwan
Teesta HEP
Teesta HEP
Teesta HEP
Asiganga Phase I
Baihetan HEP
Maojiahe HEP
Baihetan HEP
The Kanat Regulator
Description
Landslide on banks of reservoir
Buried in a tunnel
Landslide at dam construction site
Landslide at dam construction site
Buried in a tunnel
Rockfall onto workers en route
Rockfall onto quarry workers
Landslide into workers camp
Landslide at dam construction site
Landslide at dam construction site
Landslide into workers village
Landslide into workers camp
Rockfall onto quarry workers
Landslide at dam construction site
Rockfall onto workers en route
Rockfall onto workers en route
Landslide onto workers en route
Rockfall onto road construction workers
Landslide at dam construction site
Landslide into workers camp
Landslide into workers camp
Landslide into workers camp
Spoil tip landslide
Landslide into workers camp
Landslide into workers camp
Landslide into workers camp
Landslide at dam construction site
Landslide at dam construction site
Landslide at dam construction site
Landslide at dam construction site
Landslide into workers camp
Landslide at dam construction site
Landslide at dam construction site
Landslide at dam construction site
Landslide into workers camp
Landslide at dam construction site
Landslide at dam construction site

12. Temporal trends in landslide deaths associated with
major dam projects
500
150
Cumulative
number of
deaths
Annual number
of deaths
400
300
125
100
∂
75
200
50
100
25
0
0
2003 2004 2005 2006 2007 2008 2009 2010 2011 2012
Year
Annual number of deaths
Cumulative number of deaths
600

13. Landslide setting – numbers of landslides
Vajont type event
1
1
2
Construction
Landslide into workers
camp or village
5
∂
17
Rockfall or landslide at
road sites
Spoil tip landslide
Landslide on banks of
reservoir
11
Quarry landslide

14. Distribution of landslides associated with large dams
∂
Each dot is a landslide associated with a large dam in the period 2003-2012
Note:
• Almost all are in Asia
• Hotspots are in the Himalayas and in China

15. 18
Number of landslides
16
Number of Number of landslides
deaths
14
12
10
Number of deaths
8
6
4
2
0
∂
Number of
landslides
275
250
225
200
175
150
125
100
75
50
25
0
Number of deaths
Landslides associated with major dam projects

16. Time of year of dam-related landslides
Number of recorded landslides
10
9
70
60
50
40
30
20
10
0
58
36
21 19 17 18 25
51
39 35
25
17
8
7
6
5
4
∂
3
2
1
0
Month
Peak in northern
hemisphere summer
implies a predominant
rainfall trigger

17. In summary
• Until now, large dams have mostly been constructed in
upland areas with low to medium sized mountains
• Fatal landslide incidence in these areas is generally low
• Increasingly we are building dams in very high mountain
areas
• Fatal landslide incidence in these areas is high
∂
• In recent years there have been many landslides associated
with these projects during their construction, especially in
China and India
• 500 people have died in these landslides

18. Proposed dams and dam related landslides in the
Himalayan region
∂
Dam: planned or under construction
Fatal landslide associated with a dam

19. Conclusions
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