Home / Environment / News Tools: Save | Print | E-mail | Most Read | Comment
Decision time near to drain quake-formed lake
Adjust font size:

The plan to drain the Tangjiashan "quake lake" in southwest China's Sichuan Province is due to be implemented by Thursday or thereafter, with the trapped water volume having risen to 205.5 million cubic meters as of 5 PM Tuesday.

An excavator digs division channels near the Tangjiashan lake in earthquake-hit Beichuan County, Southwest China's Sichuan Province June 2, 2008. [Xinhua]

The volume was 200.8 million cubic m at 8 AM Tuesday, according to the quake control and relief headquarters with the Ministry of Water Resources (MWR).

The water level has been moving higher. It stood at 737.33 meters at 5 PM Tuesday, up 0.7 meters from 8 a.m. on the same day, and 1.8 meters higher than at 8 a.m. Monday. The water level was just 2.37 meters from the lowest point of the blockage.

To prevent the quake-formed lake from breaching its barrier and endangering survivors downstream, more than 600 armed police and soldiers raced to complete a water diversion facility on Saturday night, digging a 475 meter channel in the barrier.

The timing of actually draining the lake, however, will be decided by water inflows from its upper reaches, said Liu Ning, MWR Chief Engineer.

According to Liu, the catchment area of the upper reaches covers 3,350 sq km. It is estimated that a 2 mm rainfall in that area will mean a rise of 1 meter in the water level before the quake lake barrier.

Weather experts consulted by the Sichuan Provincial Bureau of Meteorology on Tuesday predicted scattered thundershowers and two more rainy days on Thursday and Friday around Tangjiashan lake, with rainfall to peak on Thursday night and hit 20 mm.

According to weather records, rainfall for June, July and August over the Tangjiashan area stands at 140 mm, 360 mm and 330 mm, respectively. Rainfalls of such levels would pose a grave danger to the quake lake.

Here are some key statistics regarding the May 12 quake, Tangjiashan lake and efforts to avoid further emergencies:

Human toll -- The number of those killed was 69,122 as of Wednesday noon, the Information Office of the State Council said. Another 373,606 people were injured and 17,991 others remain missing, while 45.69 million people were affected by the disaster.

Tangjiashan lake -- One of 35 lakes formed after landslides triggered by the quake blocked rivers in the mountains. Tangjiashan lake, which sits on the Jianjiang River, a local waterway, is 3.2 km from the seat of the hard-hit Beichuan County. It is inaccessible by road and can only be reached by foot or air.

Evacuation plans -- There are three plans to move survivors if necessary. The target is zero deaths, according to Tan Li, Mianyang City Communist Party chief and also chief of its Quake Control and Relief Headquarters. In the first instance, 158,000 people will have to relocate if one-third of the lake breaches its banks. Actually, more than 250,000 people in Mianyang City have already been relocated.

Two other plans require the relocation of 1.2 million people if half the lake volume is released or 1.3 million if the barrier fully opens.

Water diversion channel -- A 475 meter channel was cut into the Tangjiashan lake barrier by 620 armed police and engineers over six days and nights. The cubical channel is 12 meters deep and 7 meters wide upstream and in the middle but becomes larger downstream. Most of the workers have already left the site. A dozen police stayed behind to monitor the situation.

(Xinhua News Agency June 5, 2008)

Tools: Save | Print | E-mail | Most Read
Comment
Pet Name
Anonymous

China Archives
Related >>
- Water level of quake lake edges toward sluice
- Tangjiashan quake lake water rising
- 200,000 people evacuated to higher ground
- Emergency race to drain quake lake
- Armed police brigade arrive at major quake lake
Most Viewed >>
- Downpours threaten South China
- 10 rare flowers and plants in the world
- China still faces severe inshore pollution
- Water level of quake lake edges toward sluice
- Quake damage to the Wolong Nature Reserve
Air Quality 
Cities Major Pollutant Air Quality Level
Beijing particulate matter II
Shanghai particulate matter II
Guangzhou sulfur dioxide II
Chongqing particulate matter II
Xi'an particulate matter II
NGO Events Calendar Tips
- Hand in hand to protect endangered animals and plants
- Changchun, Mini-marathon Aimed at Protecting Siberian Tiger
- Water Walk by Nature University
- Green Earth Documentary Salon
- Prof. Maria E. Fernandez to Give a Lecture on Climate Change
More
Archives
UN meets on climate change
The UN Climate Change Conference brought together representatives of over 180 countries and observers from various organizations.
Panda Facts
A record 28 panda cubs born via artificial insemination have survived in 2006.
South China Karst
Rich and unique karst landforms located in south China display exceptional natural beauty.
Saving the Tibetan Antelopes
The rare animals survive in the harsh natural environment of the Qinghai-Tibet Plateau.
More
Laws & Regulations
- Forestry Law of the People's Republic of China
- Meteorology Law of the People's Republic of China
- Fire Control Law of the People's Republic of China
- Law on Protecting Against and Mitigating Earthquake Disasters
- Law of the People's Republic of China on Conserving Energy
More
Links:
State Environmental Protection Administration
Ministry of Water Resources
Ministry of Land and Resources
China Environmental Industry Network
Chengdu Giant Panda Research Base