21 July 2010
The Government has reportedly decided to use blasting to lower the lake at Attabad by 80 metres
Posted by Dave Petley
The Associated Press Pakistan has a report of a somewhat important development in the Attabad landslide dam story this evening. The report is of a high level meeting, chaired by the President of Pakistan, which has decided to lower the level of the lake to 30 metres (it is currently 111 metres, implying a drop of about 80 metres from the current level. This will be achieved through controlled blasting. Meanwhile a proper ferry service will be set up on the lake (at last). Finally, “it was also decided to undertake feasibility study for building by-pass as a permanent solution to the problem of landslides in the future.”
Interestingly, this decision follows a visit to China by the President. The Karakoram Highway is of great strategic importance to China. It is good to see that China has offered technical assistance, given that they have the greatest experience in operations of this type.
No timetable has been provided for the works.
Meanwhile, the latest NDMA reports suggest that the lake level has fallen by about 40 cm in the last 48 hours, possibly reflecting lower inflow rates. This means that the lake level and spillway discharge graphs are now as follows:
Dave Petley is the Vice-Chancellor of the University of Hull in the United Kingdom. His blog provides commentary and analysis of landslide events occurring worldwide, including the landslides themselves, latest research, and conferences and meetings.
NDMA Chairman General Nadeem was recently reported as saying that three big stones were hampering the flow of the lake. It would be interesting to know exactly which stones he has in mind. I of course have been pointing my finger at streambed slabs for some time, but there's something like at least six — plus possible others underneath.Getting heavy equipment to the right bank will be problematic because of recent landslides. The left bank is also a difficult place to disembarque heavy equipment as it is quite steep from the landing as the Pamir Times photos have shown. It will be interesting to see how the Chinese get this done. Getting heavy equipment from upstream would have been far, far easier some months ago.George
Government on advice of Chinese experts have decided to lower the height of lake to 30 meters. FWO has been tasked to carry out this under expert advice of Chinese. Approval at highest level has been granted to this option.It seems it has been determined by Chinese experts,NDMA,FOCUS that the barrier would not breach and collapse. The boulder/rock/fine particle matrix seems very resilient.http://www.dawn.com/wps/wcm/connect/dawn-content-library/dawn/the-newspaper/national/chinese-proposal-for-attabad-lake-accepted-by-govt-270http://www.nation.com.pk/pakistan-news-newspaper-daily-english-online/Regional/Islamabad/22-Jul-2010/Water-level-to-be-lowered-by-controlled-blasting