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Satellites Reveal Cause of Uttarakhand Flood That Devastated Hydroelectric Dams

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Re: Satellites Reveal Cause of Uttarakhand Flood That Devastated Hydroelectric Dams

#21

Post by blacklion »

latchkey wrote: post #11

I spent 2 years on a motorbike all over Northern Vietnam / Cambodia / Laos. The number of hydro dams being built by these countries (and China) in the region along the Mekong is insane. They already feel the effects from this... in the summer the rivers dry up to the point that you're driving a motorbike across dry lake beds and in the winter (aka: rainy season) there is massive landslides and the dams break and wash…

I've spent 12 months of last 10 years (~1 month/year) at same region, on motorbike, too. I could confirm your observations.

BTW, 95% of these dams are Chinese one and exports electricity to China, not to be used by locals. China build hospitals and some roads for this, which is good, but all these projects doesn't have any ecological expertise in it. And China DOESN'T CARE of course.

It is new colonialism, really.

Re: Satellites Reveal Cause of Uttarakhand Flood That Devastated Hydroelectric Dams

#22

Post by danans »

actuator wrote: post #19
idlewords wrote: post #17

Earlier quoted context omitted.

Further in the article it explains that communities often form around the remote dams, bringing people closer to the rivers, and increasing the body count when something like this happens.

But that has nothing to do with the dam itself. That should be regulated by the state authorities. Living close to rivers in such fragile places is not a good idea. Back in 2013, roughly the same place witnessed ~6000 deaths in floods. https://en.wikipedia.org/wiki/2013_North_India_floods

Based solely on my observations traveling in the area, the topography is so extreme (very steep cliffs not far from the river banks) that there is little option but to live near the river.

I'm sure there are more and less safe places on the river bank, but there aren't many places a safe distance from the river that aren't also thousands of feet up in elevation.

Re: Satellites Reveal Cause of Uttarakhand Flood That Devastated Hydroelectric Dams

#23

Post by danans »

londons_explore wrote: post #15
sradman wrote: post #9

The Feb 07 flood in India [1] was first thought to be a burst glacial lake but: > Other reports have suggested that satellite images imply that a landslide may have triggered the events... In satellite images, a 0.5 mi (0.80 km) scar is visible on the slopes of the Nanda Ghunti, a peak on the southwestern rim of the Nanda Devi sanctuary, a wall of mountains surrounding the Nanda Devi massif. [1] https://en.wikipedia.…

I was under the impression that while the exact time of a landslide is hard to predict, it is relatively easy to predict that an area of land might suffer landslides. (ie. by looking at the angle of every layer of rock and looking for any that are near their critical slippage angle) Surely that is checked for all land surrounding any hydro project, and the land stabilized with piles or grout before the hydro project…

It appears that the side of a 6000m (20000 ft) mountain collapsed.

Clearly this has happened many times through the geological history of the Himalaya - which is arguably the most extreme and dynamic mountain range on the planet - but on human timescales this is an extreme outlier event, so very hard to plan for.

Re: Satellites Reveal Cause of Uttarakhand Flood That Devastated Hydroelectric Dams

#24

Post by haltingproblem »

I used to like reading newspapers from across the spectrum. They had information and facts leavened with reasoned opinions, balanced perspectives. Reading the news media these days is no different than reading some rando on Twitter. Tragic it has come to do this.

The NY Times had a truly abominable series of articles on these all focusing on the "negligence" of the current government on building dams. Take this one for dated 2/8: "Before Himalayan Flood, India Ignored Warnings of Development Risks" [1]

Somewhere at the end:

"Exactly what caused the latest flooding was not clear as of Monday night, with the Indian government saying a team of experts would visit the site to investigate. Ranjeet Rath, the head of India’s geological survey, said initial information suggested a “glacial calving at highest altitude.” Calving is the breaking of ice chunks from a glacier’s edge."

Dams had absolutely nothing to do with this tragedy. Some folks on Twitter are claiming that Dams might have reduced casualties downstream by modulating the flow but every single article seems to have an anti-dam agenda. I too hate the aesthetic of dams because they are monolithic and massive and alter the landscape. There is something primal within us which clamors for unaltered nature. I also don't like the eyesore of the gas-fired power plant a two miles away from where I live. But I don't try to warp every tragedy and lay it at the feet of the power plant to further my aesthetic biases.

[1] https://www.nytimes.com/2021/02/08/world/asia/india-flood-ig...

Re: Satellites Reveal Cause of Uttarakhand Flood That Devastated Hydroelectric Dams

#25

Post by temp-dude-87844 »

idlewords wrote: post #17
actuator wrote: post #14

> The disaster draws attention to the controversial hydropower projects Why is this the subheading of the article? All the speculation regarding the actual flood is a glacier breaking away and falling 2km on valley floor triggering landslides and sudden water release. So, why choose to focus on something which many initially incorrectly identified as the reason for destruction. I am not saying we should not focus on…

Further in the article it explains that communities often form around the remote dams, bringing people closer to the rivers, and increasing the body count when something like this happens.

The article makes the assertion that communities often form around remote dams, and perhaps this is true for dams in the desert or dams on the plains, but maps and photos of this region reveal that the rivers here are deeply incised among steep mountains, there's essentially no arable land, and villages have been clinging to cliffs just above the rivers for as long as humans have settled here. There's simply nowhere else for them to live, and they've lived there long before any dams.

The people who died in this disaster died because a surge of water and mud and debris rushed down the river valley from high up in the mountains. You can't arrest a debris flow [1], you either have to hope it doesn't happen, or engineer at great cost that it doesn't happen, or you pre-emptively relocate to a place where you won't be caught in it. These are hard choices, but the nature of the problem is simple, and traces back to topography..

[1] You can arrest a debris flow with a very large embankment of your own, preferably if there's no lake behind it; water is not compressible, so a debris flow into a reservoir will always risk overtopping the dam with a frighteningly large wave. But, putting dry dams in a narrow river valley is much more complex than dams behind which water can collect.

Re: Satellites Reveal Cause of Uttarakhand Flood That Devastated Hydroelectric Dams

#26

Post by zdragnar »

silexia wrote: post #20
actuator wrote: post #14

> The disaster draws attention to the controversial hydropower projects Why is this the subheading of the article? All the speculation regarding the actual flood is a glacier breaking away and falling 2km on valley floor triggering landslides and sudden water release. So, why choose to focus on something which many initially incorrectly identified as the reason for destruction. I am not saying we should not focus on…

Big oil has been funding anti - nuclear and anti - hydro efforts for years. The truth is that far more people die from pollution from fossil fuels than have ever died from nuclear or hydro.

That is rather self fulfilling, though. We produce and use significantly more fossil fuels than we have nuclear or hydro power.

If the whole world was run by hydro and nuclear, and fossil fuels were relegated to somewhere between non-existent or hyper-regulated, it wouldn't be a stretch to imagine the reverse as well.

Re: Satellites Reveal Cause of Uttarakhand Flood That Devastated Hydroelectric Dams

#27

Post by vagrantJin »

blacklion wrote: post #21
latchkey wrote: post #11

I spent 2 years on a motorbike all over Northern Vietnam / Cambodia / Laos. The number of hydro dams being built by these countries (and China) in the region along the Mekong is insane. They already feel the effects from this... in the summer the rivers dry up to the point that you're driving a motorbike across dry lake beds and in the winter (aka: rainy season) there is massive landslides and the dams break and wash…

I've spent 12 months of last 10 years (~1 month/year) at same region, on motorbike, too. I could confirm your observations. BTW, 95% of these dams are Chinese one and exports electricity to China, not to be used by locals. China build hospitals and some roads for this, which is good, but all these projects doesn't have any ecological expertise in it. And China DOESN'T CARE of course. It is new colonialism, really.

> China build hospitals and some roads for this, which is good, but all these projects doesn't have any ecological expertise in it. And China DOESN'T CARE of course.

But isn't the honesty refreshing? They don't come with guns or bibles or any notion of superiority. Just preying on the weak willed. I call that good business.

Re: Satellites Reveal Cause of Uttarakhand Flood That Devastated Hydroelectric Dams

#28

Post by Retric »

temp-dude-87844 wrote: post #25
idlewords wrote: post #17

Earlier quoted context omitted.

Further in the article it explains that communities often form around the remote dams, bringing people closer to the rivers, and increasing the body count when something like this happens.

The article makes the assertion that communities often form around remote dams, and perhaps this is true for dams in the desert or dams on the plains, but maps and photos of this region reveal that the rivers here are deeply incised among steep mountains, there's essentially no arable land, and villages have been clinging to cliffs just above the rivers for as long as humans have settled here. There's simply nowhere…

[1] is correct but the process drastically reduces the energy and peak flow rates. Assuming the dam survives it makes a large difference for people down stream.

Visually it’s hard to notice but even just 1 foot matters in a flood.

Re: Satellites Reveal Cause of Uttarakhand Flood That Devastated Hydroelectric Dams

#29

Post by pashsdk27 »

actuator wrote: post #19
idlewords wrote: post #17

Earlier quoted context omitted.

Further in the article it explains that communities often form around the remote dams, bringing people closer to the rivers, and increasing the body count when something like this happens.

But that has nothing to do with the dam itself. That should be regulated by the state authorities. Living close to rivers in such fragile places is not a good idea. Back in 2013, roughly the same place witnessed ~6000 deaths in floods. https://en.wikipedia.org/wiki/2013_North_India_floods

The biggest reason why most people prefer to live near the rivers in this region is water. A lot of the villages up in the mountains do not have running water and you have to hike a few kilometers down the valley to get water from hand-pumps and small streams. That was the case when I last visited my grandparent's village in Uttarakhand. Even my hometown which is one of the largest towns in the region has water problems. It gets worse the higher you go in the Himalayas.

Landslides are also a major factor as the mountains are extremely fragile. I've witnessed several such small landslides during my trips that often block the small mountain roads. They are very common.

There is pretty much no usable agricultural land and most villages rely on money from people working outside the region or small scale cattle domestication. Upper Himalayas is a rough terrain and so not many people live there. Living closer to the rivers is much better. Even better is living closer to the major roads that often are closer to the rivers.

Things are slowly and steadily improving these days. The regulations are also being more strictly enforced. Though I'm quite concerned that many similar disasters will happen in the future due to climate change. :/

Re: Satellites Reveal Cause of Uttarakhand Flood That Devastated Hydroelectric Dams

#30

Post by erentz »

zdragnar wrote: post #26
silexia wrote: post #20

Earlier quoted context omitted.

Big oil has been funding anti - nuclear and anti - hydro efforts for years. The truth is that far more people die from pollution from fossil fuels than have ever died from nuclear or hydro.

That is rather self fulfilling, though. We produce and use significantly more fossil fuels than we have nuclear or hydro power. If the whole world was run by hydro and nuclear, and fossil fuels were relegated to somewhere between non-existent or hyper-regulated, it wouldn't be a stretch to imagine the reverse as well.

It’s compared on a deaths per unit of energy produced basis. Kind of like how we compare stats per capita between countries of different sizes.
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