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Comment by saagarjha | Hacker News Reader

I'm pleasantly surprised to see that they've been able to survive this long without access to food and possibly clean water. I can't imagine what it would feel like to be stuck in a cave for nine days and then suddenly see two divers show up as part of the rescue effort!

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> rescuers have said they may have to wait several weeks for the water to subside before they can be taken out.

Ouch

> Trying to take non-divers through a cave is one of the most dangerous situations possible, even if the dives are relatively easy. That also begets the question: if the dives are difficult then supply will be difficult, but the risk of trying to dive them out is also exponentially greater

>have to wait several weeks

A BBC article said it could be months, much less weeks. It's the beginning of the rainy season.

https://www.bbc.com/news/world-asia-44692813

It's interesting, I wonder what the pros and cons are for drilling to retrieve them or send supplies. In the mine collapse situations that I'm aware of, there was already infrastructure on hand for heavy equipment and drilling.

I have to imagine that the dangers of cave diving are multiplicative - you don't get enough skill-based improvement from any given trip into/out to make repeated trips a safe option.

I'm sure I don't understand the scale of this. I would however think that you can bring huge industrial pumps and do some plumbing to a suitable place to dump the water and turn them on. Holland once send 7 million ton a day of pumping capacity to England to help them out. Could that not make a serious impact on the water levels in the cave?

Industrial scale pumps certainly exist, but they aren't exactly small and easily portable. I'm not familiar with the one Holland sent England, but I suspect it was pre-assembled on a ship?

The highest capacity pumps in New Orleans can move roughly 10,000 gallons a second, but they require a supply "hose" that's ~8-10 feet in diameter to reach that volume. You'd need to get an enormous hose to a low point of the cave system, which may not be near the entrance.

Then there's the question of what to do with the water you pump out. Maybe there's a river nearby that can absorb it?

It is doable, but it's neither simple, not particularly quick.

Also, the pumps have to be at the lowest point, pushing the water up - a siphon has a maximum height that a vacuum can draw water up of around 10m.[0] You can't just stick the pump at the entrance and then shove a pipe hundreds of meters down the cave system, you need to take the pump down there and run the hose back to the outside.

0. https://en.wikipedia.org/wiki/Siphon

I did not think of that.

My suspicion is that it isn't so much pumping capacity that's the issue but complexity.

One more benefit they had with the mine was that they knew where it was and had it mapped. As far as I know no-one knows where to drill above ground to get to the chamber.

Ah, that's a subtle but in retrospect obvious consideration. Fascinating stuff to think about.

Stupid question. If you manage to drill down to the cave, don't you pierce the air bubble that prevents the water from rising and flooding the cave?

Caves are quite permeable. It's not air pressure holding back the water, it's just a matter of how much water there is (the cave goes into the side of a mountain, it doesn't just go down into the ground).

The first dive is the hardest. You can install a line during it, which you will use for subsequent dives that will secure you next attempts.

you can survive over a month without food, but they must have found some water.

update: they are surrounded by water which gets contaminated by their excrements. not good.

They were stuck in a cave that was flooding. Plenty of water to go around. Probably not the cleanest but will do in an emergency.

Diarrhea will make you die a lot faster, your attitude is a bit blasè for water that is potentially contaminated with feces.

It's not like someone from the US who has only drank clean processed water

Why would there be feces? They aren't in sewers.

And even if there was a chance of diarrhoea, what would be your alternative?

In flood waters? Because there is a little bit of everything in flood waters.

Apparently there is water seeping into the space they are in. I'd drink that before I'd drink the inundation water.

But that's exactly what the GP said.. they are being flooded.

>Why would there be feces?

Because they have to go too.

They are being flooded, fresh water goes in.. most likely along the walls too.

Yes, I'd like to know where they found water clean enough to drink, or a way to make it clean. Floodwater runoff is probably not the best thing to ingest…

Can't find the link, but saw a video of someone of the rescue team explaining there is drinkable mineral water streaming off the walls in the cave.

Note everyone is used to having chlorinated and flouride(d) water so their bodies might have been used to relatively dirty water. Of course, I could wrong in their case...don't know their background

How prejudiced of you :) Most places in Thailand have access to purified water for drinking.

Here is an article from Cambodia, where they are some years behind: https://medium.com/make-a-difference/bringing-clean-water-to...

ha! They down-voted me apparently. To those that down-voted me: Not everyone can turn the tap on and get clean water. Even if Thailand has it today, they probably didn't have it yesterday. When you drink from dubious sources, unless you die as a child, you gain some sort of immunity. A techie from SF can get sick and even die, but a local can drink from the same source and nothing happens to him /her.

Thais mostly drink bottled water, which is clean. They aren't drinking river water or something. Most of Thailand lacks drinkable tap water. Food hygiene standards are more lax than in the West though.

>> Thais mostly drink bottled water, which is clean. They aren't drinking river water or something.Most of Thailand lacks drinkable tap water.

Thanks for the inside info. But do they brush their teeth with bottled water? Do they wash their dishes, tomatoes with bottled water or with "dirty" tap water?

I'm a techie from EU and have survived to tell the story of multiple tooth brushings with tap water in Thailand.

Sarcasm aside, I'm sure it varies from place to place, but in places I've been to in Thailand (and I live half there, half EU), tap water is fine for washing/brushing and if anything, too chlorinated (and thus not too drinkable). I still drink bottled water (or filtered water; many local friends have filters installed to their tap).

I think most people in Thailand do all of those things with tap water, but there may be exceptions in especially poor, isolated or rural areas. In Bangkok the debate has advanced to whether the water is actually drinkable now (in much of the city the answer is probably yes).

I’m from North Africa, and this is very true. If you haven’t grown up drinking the tap water there, it will make you very sick. But locals drink it without problem.

They are now expected to have to survive in the cave for several months more, before rescue :(

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