Shimla, June 27
The flood threat due to the Parechu lake in Tibet, which kept the people living along the banks of the Sutlej on tenterhooks for the past over a year, seems to have subsided. The latest satellite imageries reveal that the blockade on the Parechu river has breached and a major portion of the water has drained out, causing flash floods in a 200-km stretch of the Sutlej from Sumdoh to Sunni.

While the exact dimensions of the residual water body were not available, the picture clearly showed that the elongated tail of 4.6 km has completely dried up and the bed of the upper portion of the main lake was also visible. The National Remote Sensing Agency (NRSA) has worked out that the area of the lake had been reduced to less than 100 hectares from 210 hectares in April 2004.

A good part of the 280-metre long and 116-metre wide (at the base) blockade has eroded on the lake side and the blockade point has shifted towards the outflow point. It indicates that the height of the blockade, which was 75-metres from the base in April as per the data provided by the Chinese authorities, has been reduced significantly.

Though the NRSA will take some time and pictures of higher resolution to exactly work out the dimensions of the lake, it is apparent that a shallow water body has been left after the breach. The people and the administration will heave a sigh of relief, at least for the time being, even though the blockade has not been cleared completely and fresh landslides in the fragile mountain ranges could again raise the height of the blockade.

While there was no loss of life on the Indian side, the Army authorities spotted bodies of six Chinese during the floods yesterday which were apparently washed down from three low-lying villages on the other side of the border that bore the brunt of the Parechu’s fury. The local police received a report that a body had been sited today near Khab in the river. A party had was to recover it

The fact that the blockade did not give way completely proved a blessing in disguise as a sudden burst could have led to an August 2000 flood-like devastation. Even then the amount of water, which gushed through the river, was too huge. Engineers of the Satluj Jal Vidyut Nigam have worked out the maximum discharge at Nathpa Dam at 4,500 cumecs, which is the second highest to date after August 2000 when it touched 6,500 cumecs. The silt content during the floods crossed 1,50,000 ppm (parts per million) as against the normal level of 1,000 to 2,000 ppm. The 1500 MW Nathpa Jhakri project has been designed for a maximum silt level of 5,000 ppm.