Glacial lake outburst
T he glacial lake outburst of the Lemthang Lake last Sunday has taught us many lessons.There was a general panic as the sirens were heard through the valley. The people in the lower level were moved to the higher level. It has been reported that some bridges has been washed away making Laya cut from the rest of the Dzongkhags and the country. The restoration is said to take about two months,
The Home minister tweeted that His Majesty the King has most graciously commanded the Royal Bhutan Army for reconstruction of the Tongsho bridge over the Mochu which was washed away by the flood along with several other smaller bridges in Laya. It comes at a time when all the able-bodied people of Laya are out in the mountains collecting Cordyceps and are stranded without the bridges connecting to their villages. Laya stands totally cut off from Gasa or Lingzhi after the Shinchey La lake outburst.
The restoration of the bridges over Tongtsho has already started with the 23 army personnel from Wangdue and as per the Dzongkhags officials all the required materials has reached the site. And is expected that Laya will be connected within a month or so.
As Bhutan has more than 2,674 glacial lakes and 25 of them are rated as potentially dangerous glacial lakes. Lemthang Lake which burst last week is also categorized as dangerous one and government has promised that it will carry out the assessment of all dangerous glacial lakes within the country and install sirens systems in all the potential dangerous glacial lakes.
On the other hand a research carried out by the international organizations stated that one of the reasons for the outburst of glacial lake is the rise in temperature and earthquake. It states that with the rise temperature the sun will eventually hit the newly exposed ice. After the sun melts the ice and end up creating a possible flood which in preventing is difficult.
In order prevent that we may have to refrain from doing all things that leads to global warming, artificial deepening of the spill way and lowering of the water level by artificial means. The other means would be to install effective early flood warning systems that will save the life of many people, animal and property.
However on the other hand it is equally important to prepare the inventories of the glacial lakes and identify for further investigations. A lake monitoring system is designed and implemented. A set of indicators may be designed to classify the lakes according to the risk. After that upon the method chosen, the site investigations are carried out and the lake drainage designed and implemented to save life and property.