Calculation of mountain lakes outburst hydrographs

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Lomonosov Moscow State University Faculty of
Geography
Calculation of mountain lakes outburst hydrographs
Kidyaeva Vera
FIRST VINOGRADOV'S READINGS. FUTURE OF HYDROLOGY
Saint-Petersburg, 2013
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The importance of the mountain lakes studies
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Parts of the mountain lakes research
1. Potentially hazardous lakes search 2.
Surveying and monitoring 3. Morphometrical and
hydrological characteristics determination 4.
Regional relations determination 5. Potential
outburst possibility evaluation 6. Scenarios of
the outbursts 7. Lake outburst hydrographs
calculation/evaluation 8. Mathematical
simulation of floods or debris flows 9. Spatial
distribution of the flood or debris flow
parameters 10. Intensity and hazard zoning in
river valley 11. Social and infrastructure
vulnerability assessment 12. Risk evaluation
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Objects
Mountain lakes
Barrier
Glacial

• ice-dammed
• moraine dammed
• proglacial
• rock, and etc.

• Caused by
• lanslides, mudslides
• debris flows, and etc.

Study areas Central Caucasus, Russia (Elbrus
region) Sichuan Province, China (region of the
12.05 Wenchuan earthquake)
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Outburst or overflow hydrographs and maximum
discharge evaluation

• field surveys
• empirical formulas and methods
• water-balance methods
• mathematical and hydraulic outburst models
• hydrodynamic modeling

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Measured hydrographs
Position Distance from Tangjiashan Dam, km Peak discharge, m3/s Occurrence time
Tangjiashan dam 0 6500 1230
Beichuan hydrologic station 4.6 6540 1250
Tongkou hydrologic station 26.0 6210 1350
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Modeling the outburst flood that occurred in
10-12 of June 2008 after the artificial cut at
the dam
the dam
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Empirical formulas
Probable maximum discharge of sudden breaks of
ice dams Qmax W/t (1) or for
moraine-dammed lakes Qmax 2W/t (2)
Subglacial drainage of ice dammed lakes
(3)
Qmax maximum discharge, m3/s, W - volume in
m3, t - drainage duration in seconds, t 1000 s
for maximum estimates

1. Haeberli, W. 1983. Frequency and characteristics
   of glacier floods in the Swiss Alps. Annals of
   Glaciology, 4 8590.
2. Huggel, C. et. al. 2002. Remote sensing based
   assessment of hazards from glacier lake
   outbursts a case study in the Swiss Alps.
   Canadian Geotechnical Journal, 39 316330.
3. Clague, J.J., and Mathews, W.H. 1973. The
   magnitude of Jökulhlaups. Journal of Glaciology,
   12 501504.

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Ice-dammed glacial lake outburst 11 august 2006
Water-balance method based on field surveys
Q, m3/s

• Parameters
• Estimated volume of the flood 420 000 m3
• Maximum discharge of the flood 20 m3/s
• Volumetric concentration of the
• debris flow 0.42

Chernomorets S., Petrakov D., Tutubalina O. 2007
Glacial lake outburst in the north-eastern slope
of Mount Elbrus August 11, 2006 the forecast,
the event and the consequences// Materials of
glaciological studies.? 102. P. 211215.
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Results
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Mathematical and hydraulic models
Computational model by Yu. B. Vinogradov for
outburst through ice tunnel
?0 - water density, 1000 kg/m3 ? - water and ice
density, 850-910 kg/m3 g - gravitational
acceleration, 9.81 m/s2 r - latent heat of fusion
of ice, 334 000 J/kg l - length of the tunnel,
550 m h - excess between entrance and the exit of
the tunnel, 61 m W0 - volume of the lake before
the outburst, 821 000 m3 a, m - morphometrical
parameters of the lake C0 - specific mass heat
capacity of water, 4190 J/kg?? t - lake water
temperature, 2,5 ??
for Bashkara lake
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Mathematical and hydraulic models
lake
Gnezdilov Ju., Ivashchenko E., Krasnikh N. 2007
Evaluation of a hypothetical ouburst of the Lake
Bashkara // Proceedings of "Sevkavgiprovodhoz",
Issue 17, p.127-149.
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Mathematical and hydraulic models
Computational model for a step-shaped schematized
lake hollow by V.Mochalov and I.Zuckerman
 
Tangjiashan barrier lake
 

 
 
W volume of the lake, m3 S- surface area, m2 Z
depth, m Z? depth of the spillway, m k
spillway koef. ß erosion intensity koef., m-2
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Mathematical and hydraulic models
 
Tangjiashan barrier lake outburst, 10-12 of June
2008
vs.
?
t, h
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36
0
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Hydrodynamic simulation
The Tangjiashan Barrier Lake overflow in case
of huge rockfall (volume gt 106 m3). The dam is
stable
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Methodology two-dimensional hydrodynamic
simulation, using River model by V. Belikov,
A. Militeev
Saint-Venant equations
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Digital terrain model of the valley
Irregular rectangular-triangular grid
lake
dam
riverbed
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Simulated overflow discharge at the dam of the
Tangjiashan Lake, the highest peak 5000 m3/s
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Some results
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Thank you for your attention
??????? ?? ????????
I thank Krylenko I.N., Norin S.N., Chernomorets
S.S., Petrakov D.A. and Su P. for help and useful
discussion
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Parts of the research
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