IAPRS & SIS, Vol.34, Part 7, “Resource and Environmental Monitoring”, Hyderabad, India, 2002 
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LANDSAT TM 06-Aug-2000 
III) The Manasarovar Lake: The Manasarovar Lake is 
connected to the Sutlej River basin through a stream channel. 
Study of the temporal imagery suggesting that there was no 
evidence of overflow from these lakes onto the Sutlej River via 
the connecting channel during floods hence, the possibility of 
contribution of water from these lakes to the Sutlej River can be 
ruled out. 
IV) Cloud burst/Snowmelt: There was a widespread rainfall 
in the Himachal Pradesh and adjoining Tibetan plateau during 
July last week. Massive cloud cover over the Sutlej river basin 
was noticed on temporal data of IRS-1C/ID-WIFS. Hence, 
there was a high possibility of cloudburst in the Tibet region 
and adjacent Himachal Pradesh, hence the same could have 
contributed the flash flood on August 1 to a large extent. A 
Study of temporal IRS-1C/1D-WIFS & IRS-P4 data suggesting 
that snowmelt in the upper Sutlej river catchment area might 
also partly contributed towards the floods. It is evident from the 
examination of satellite imagery, a gradual decrease in snow 
cover extent from the middle of July to 1* week of August 
2000. The widespread rainfall together melted snow might have 
also contributed to this havoc to a large extent. 
V) Sutlej water discharge during the event: Analysis of the 
Sutlej River discharge data of August 1, 2000 at Rampur gauge 
station clearly indicating that the hydrograph during the flash 
flood period was something unusual. The discharge at this 
gauge station was rose from 54,200 cusecs (0300hrs) to 92,400 
cusecs (0500hrs) just in 2 hours time and by another half an 
hour i.e. by 0530 hrs it rose to a peak flow of 1,80,000 cusecs. 
It receded to 1,18,000 cusecs by 0630 hrs and the same trend 
continues for another 2 hrs. By 0900 hrs, it returned back to 
normal flow of 50,000 cusecs. The six-hour abnormal flow, 
which accounted for 2262 million cubic feet, was almost 3 
folds higher than normal flow of 864 million cubic feet. 
Usually hydrographs of such type will be associated with cloud 
burst and unusual snowmelt of shorter duration (See Fig.3) 
Flood Discharge of Sutlej River on 01-Aug-2000 
at Rampur, Simla district, Himachal Pradesh 
180,000 | = lu a 
160,000 | 
140,000 = 
120,000 = 
100,000 
80000 E—— 
60,000.54 
    
3:00 400 5:00 530 6:00 7:00 8:00 9:00 
Courtesy: NRSA €4———9 Discharge in Cusecs | 
  
  
VI) Earthquake data provided by USGS: indicating that four 
earthquakes on moderate scale have been recorded in and 
around the Sutlej basin by USGS and IMD stations for the 
period June-July, 2000. However, no quakes were recorded at 
least one week prior to the flood event. Landslides of recent 
origin have been identified at few places along the Sutlej River 
and probably these landslides might have triggered by 
earthquakes. 
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