You are browsing the archive for Landslides Mudslides.
8 June 2008
Updated@ Tangjiashan images deepen the mystery
NB – I have now updated this with an image at the end that shows this more clearly. A quick image search today showed up the following Reuters image, entitled: “Water from the Tangjiashan “quake lake” flows down in quake-hit Mianyang, Sichuan Province June 7, 2008. Chinese troops on Saturday eased pressure on a swelling “quake lake” threatening hundreds of thousands of people, but a smaller lake burst its banks …
An update on Tangjiashan
I thought that this would be a good time to review the situation with Tangjiashan now that water has been flowing for over a day. 1. Water flow is now apparently about 21.5 cumecs – up from 10 cumecs at about the same time yesterday. This is still not enough to balance inflow, so the lake level continues to rise. Of course as the lake level increases the rate of …
7 June 2008
What is going on at Tangjiashan?
First thanks to both Ripen and Hideo Ototake for their emails and images on this issue. I remain somewhat confused about what is going on at Tangjiashan. We know that the sluice now has flow within it – that is not in doubt. But what is happening with that flow is very hard to understand. First, let’s work out the flow rate needed to maintain a constant lake level. The …
Updated: Tangjiashan – flow rate information
Xinhua is now reporting that the discharge in the sluice has now reached 40 cubic metres per second. This means that it is less than half that required to balance inflow at the current rate (c. 100 cubic metres per second). So far at least the channel is apparently stable. The same report indicates that the lake volume is now 229.5 million cubic metres. This is good news. The lake …
Updated: Flow begins through the channel at Tangjiashan
Various media sources are reporting that water began to flow through the channel at Tangjiashan today. For example, Reuters is reporting that:“Chinese troops began easing pressure on a dangerously swollen “quake lake” on Saturday, with water gushing into a man-made sluice in an operation monitored by satellite.” The dam and channel now has to survive two critical phases. The first lies in the next day or two, with increasing volumes …
6 June 2008
Tangjiashan – delayed again
Xinhua is now reporting that the flow through the sluice has now been delayed through the use of a 60 cm high temporary dam (see below). This is an interesting development – I wonder why they have decided to do this at this late stage. Delaying the flow has a risk associated with it as the body of water will be larger, and thus the flood is potentially more damaging. …
Tangjiashan – here we go…
Xinhua has reported in the last 20 minutes that:“Water level of China’s main quake lake Tangjiashan climbed to the critical point of 740 meters on a sluice channel at 0:00 a.m. Saturday, but the long-awaited drainage hasn’t started yet.” Given that we know that it has been raining in the area this afternoon, over-topping must be about to start. Hold onto your hats…! And can I just say good luck …
Tangjiashan – overtopping is imminent
Xinhua is reporting that over-topping of the Tangjiashan dam is now absolutely imminent. They Chinese media have reported that the water level in the dam rose to 739.52 metres above sea level at 4 a.m. GMT today. This is 48 centimetres from the bottom of the channel. It appears that further evacuations are now underway. More as and when information becomes available.
4 June 2008
Updated: Tangjiashan (Beichuan) dam – a summary of what we know
In the next 24-48 hours the water level at Tangjiashan should reach the spillway and flow should start. I thought therefore that it would be useful to summarise what we know about the site: The landslide dam is 124 metres high; At the time that the over topping begins the lake will have a volume of about 205 million cubic metres of water (UPDATED – the volume is now estimates …
3 June 2008
Tangjiashan – CCTV footage of the channel
There is a very good film (in Chinese) of the Tangjiashan landslide. It is available at: http://video.sina.com.cn/news/c/v/2008-06-03/084017059.shtml The first 6 minutes or so are worth a look. Early in the video they fly a helicopter over Beichuan, which shows the damage caused by landslides there. They then land the helicopter on the landslide mass and the reporter goes into the channel. It appears to be about 5 m wide at …
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.
Recent Comments