lake sarez risk mitigation project
TRANSCRIPT
SEMINARI MAGGIO 2015
Lake Sarez Risk Mitigation Project
Alessandro Palmieri Water Infrastructure Adviser
former Lead Dam Specialist, World Bank
Outline
The Highest Dam in the World The Lake Sarez Risk Mitigation Project Studies and Risk Assessment Monitoring and Early Warning System Long Term Solutions
The highest dam in the world
Sarez
Lake Sarez was formed in 1911 when an earthquake initiated a 2km³ landslide which dammed the Murgab river in the Pamir
The lake that formed behind this landslide dam now has a volume of 17km³ (half the volume of Lake Geneva)
The Lake Sarez Risk Mitigation Project
To help alert and prepare vulnerable people in the case of a disaster associated with an outburst flood from Lake Sarez and other frequent natural hazards such as mud-slides, rockfalls, avalanches, and seasonal floods.
Lake Sarez Risk Mitigation Project (2001- 2006)
Development Partners and Contributions
Contribution (MUS$)
GoT, 0.17
SECO, 2.9
AKDN, 0.5
USAID, 0.25IDA, 0.47
Studies and Risk Assessment
Lake level evolution 1938-2005
3230
3235
3240
3245
3250
3255
3260
3265
3270
3275
3280
1938
1941
1944
1947
1950
1953
1956
1959
1962
1965
1968
1971
1974
1977
1980
1983
1986
1989
1992
1995
1998
2001
2004
Lake
leve
l (m
Internal Erosion
3000
3500
Average hydraulic gradient: 10 %
Canyon(11,4 %)
Critical gradient: 30 % Probable piezometric line
Hazard Identification
Landslide volume geometry velocity wave height
Length l Lake depth d
Height h
Sliding velocity v
Width W
Comparison • Lituya Bay • Tafjord • Flores • Vajont
overtopping failure max = 2.88E-050.3 1.44E-05 sum= 5.93E-05
overtopping wave0.3 no overtopping failure
fast 0.70.2
no overtopping wave0.7
volume 0.2 to 0.6 km3 overtopping failure0.1 0.1 6.40E-06
overtopping wave0.1 no overtopping failure
slow 0.90.8
no overtopping wave0.9
landslide overtopping failure1 0.1 5.76E-06
overtopping wave0.01 no overtopping failure
fast 0.90.8
no overtopping wave0.99
volume < 0.1 km3 overtopping failure0.9 0.01 1.44E-07
overtopping wave0.01 no overtopping failure
slow 0.990.2
no overtopping wave0.99
no landslide0
MCE0.008 piping failure
0.5 2.88E-05piping
0.5 no piping failureinternal change 0.5
0.8no piping
0.5toe instability piping failure
0.9 0.5 1.44E-06piping
0.1 no piping failureno internal change 0.5
0.2no piping
0.9pressure wave piping failure
0.02 0.5 2.00E-06piping
0.5 no piping failureinternal change 0.5
0.5no piping
0.5no toe instability piping failure
0.1 0.5 4.00E-07piping
0.1 no piping failureno internal change 0.5
0.5no piping
0.9no pressure wave
0.98
6 . 10-5
Tree of Consequences
Monitoring and Early Warning System
N
Lake Sarez
canyon
LakeShadau
MU1
GPS points
MU1
GPS points
MU4
2 PLL2 WLL
MU4
2 PLL2 WLL
MU9 a+b
1 Gauging Station(2 devices)2 x 2 FS
1 Flood Panel
MU9 a
Gauging Station2 x 2 FS
MU6
1 SMA1AWS
MU6
SMAAWS
CU
TransmissionManual trigger
CU
TransmissionAAP
Barchidiv
MU5
GPSpoints
MU5
GPSpoints
MU2
SMA
MU2
SMA
MU8
SMA
MU8
SMA
MU7
2 x 2 FS
MU7
2 x 2 FS
Data Acquisition
N
Lake Sarez
canyon
LakeShadau
MU1
GPS points
MU1
GPS points
MU4
2 PLL2 WLL
MU4
2 PLL2 WLL
MU4
2 PLL2 WLL
MU4
2 PLL2 WLL
MU9 a+b
1 Gauging Station(2 devices)2 x 2 FS
1 Flood Panel
MU9 a
Gauging Station2 x 2 FS
MU6
1 SMA1AWS
MU6
SMAAWS
CU
TransmissionManual trigger
CU
TransmissionAAP
Barchidiv
MU5
GPSpoints
MU5
GPSpoints
MU2
SMA
MU2
SMA
MU8
SMA
MU8
SMA
MU8
SMA
MU8
SMA
MU7
2 x 2 FS
MU7
2 x 2 FS
Data Acquisition
Scale : ~1/100’000
MU: Monitoring Unit
CU: Central Unit
Cable connection :
Mini C transmission
AWS: Automatic weather station
Legend
GPS: Global Positionning System
SMA: Strong Motion Accelerograph
PLL: Precise Lake Level Measurement
WLL: Wide Range Lake Level Measur.FS: Flood sensor
Scale : ~1/100’000
MU: Monitoring Unit
CU: Central Unit
Cable connection :
Mini C transmission
AWS: Automatic weather station
Legend
GPS: Global Positionning System
SMA: Strong Motion Accelerograph
PLL: Precise Lake Level Measurement
WLL: Wide Range Lake Level Measur.FS: Flood sensor
Instruments of the MS & EWS
GPS
Strong Motion Accelerograph (SMA)
Water level
WLL (3240.00)
PLL (3250.00)
Cable in trench
Connection in the Dam-house to the EWS
Cable laying on the bottom of the lake
Connecting box (3280.00)
max. static water level 3270.00
Flood sensors
Gauging station
Shelter
Flood sensors and radars
Gauging station
Dam House
Dam House
Data Analysis
Alarm system
Alarm in the villages
Long Term Solutions: Lake Sarez Hydropower
Concept
Risk reduction
Lowering the Lake Level: time to achieve lowering
315031603170318031903200321032203230324032503260
0 1 2 3 4 5 6 7 8 9 10 11 12
time to drawdown (years)
lake
leve
l (m
asl)
70m3/sec total outf low
80m3/sec total outf low
Plant Factor and Electricity Generation
0
50
100
150
200
250
300
0 1 2 3 4 5 6 7 8 9 10 11 12
time (years)
pow
er (M
W)
Qmax< 80m3/s
Qmax< 70m3/s
Power peaks at 220 - 250MW during lake drawdown.
Annual energy peaks at 2000 GWh/year, and settles at a long term value of 1100GWh/year.
In the long term the station could be operated to generate peaking power with a plant factor of about 50%.
Scheme Layout, plan view
Underground HPP
Head works
Tail works
Hydraulic interconnection
Hydropower Plant – Conceptual Profile
3500 masl
H= 460m
2500 maslL= 4,1 km
3260 masl
Lake Shandau
Pressure Tunnel
Pressure ShaftPower House
Lake Piercing
Lake Sarez Hydro: a way to remove the
hazard, and generating economic growth