how long can you be in cold water

rosehips

Mr. Boo is watching you.
Super Member
Registered
Joined
Feb 14, 2011
Messages
808
Reaction score
58
Location
Burgundy, France
Website
www.upwork.com
My characters are going to have to swim through water that has accumulated in a cave. I don't have an exact temperature in mind, but I imagine it's quite cold. How long can they handle the cold water before it becomes a serious problem?

ETA: what is the likely temperature of water in a cave in fall in the northeast of the US?
It's been raining.
 
Last edited:

neandermagnon

Nolite timere, consilium callidum habeo!
Super Member
Registered
Joined
Oct 25, 2014
Messages
7,272
Reaction score
9,338
Location
Dorset, UK
AFAIK it's more a question of what temperatures can you actually swim in. Years ago I went on a boating holiday (small boat with a cabin) along the Caledonian Canal (where Loch Ness is, and the canals/waterways that run across that part of Scotland) and we were informed that life jackets should be worn on deck at all times no matter how good you are at swimming as the water temperature was so cold that all your muscles seize up and you can't swim. This was in August, though Scotland isn't known for warm summers LOL - it rained nearly the entire time we were there and warm clothes + waterproof jackets were essential gear - and life jackets help to keep you warm.

That said, there are people who do cold water swimming - not sure how long they stay in the water. They train for that sort of thing. Being in cold water can be a shock to the system, so people who haven't trained for things like that would be worse affected. Maybe someone with cold water swimming experience will give a more accurate answer.
 
Last edited:

rosehips

Mr. Boo is watching you.
Super Member
Registered
Joined
Feb 14, 2011
Messages
808
Reaction score
58
Location
Burgundy, France
Website
www.upwork.com
AFAIK it's more a question of what temperatures can you actually swim in. Years ago I went on a boating holiday (small boat with a cabin) along the Caledonian Canal (where Loch Ness is, and the canals/waterways that run across that part of Scotland) and we were informed that life jackets should be worn on deck at all times no matter how good you are at swimming as the water temperature was so cold that all your muscles seize up and you can't swim.

Thanks, this is a great point. I may have to come up with something magical to mitigate this problem (it's fantasy story). I appreciate your pointing it out.
 

talktidy

Super Member
Registered
Joined
Aug 14, 2014
Messages
896
Reaction score
86
Location
Fabulous Sweyn's Eye
I am no expert on this subject, but I remember watching a programme on the telly about what happens to people when dunked into very cold water.

Apparently, the body reacts with an automatic gasp, a drawing in of breath, beyond the capability of the submerged person to control. So one can imagine what happens when that individual's face is beneath the surface of the water.

I seem to also remember that in very cold water there was even mention of an individual's heart stopping with sudden emersion.

I suppose it all depends on what conditions you need to serve your plot. Perhaps there is a handy hydro-thermal source warming the water to bearable levels?
 

Tocotin

deceives
Super Member
Registered
Joined
Aug 3, 2008
Messages
2,250
Reaction score
1,895
Location
Tokyo, waiting for typhoons
Hey, right now I'm watching a super interesting documentary about wrecks in Lake Superior, and they (the people in the video, not the wrecks!) have just said that it'll be about 15 minutes before hypothermia sets in.

:troll
 

frimble3

Heckuva good sport
Super Member
Registered
Joined
Oct 7, 2006
Messages
11,574
Reaction score
6,396
Location
west coast, canada
Fat people might last a little longer, because the core would have a little more insulation. And, training until you're accustomed to cold water, etc. This is why people train for things like 'polar bear swims' (for most people, a brisk run into the water and a scamper out) and cold-water swimming.
As others have said, it's the initial shock, then the sucking away of body heat.
 
Last edited:

jclarkdawe

Feeling lucky, Query?
Super Member
Registered
Joined
Jan 18, 2007
Messages
10,297
Reaction score
3,859
Location
New Hampshire
When you say the "northeast of the US," you can mean two very different areas as far as water temperature, assuming we're talking about the ocean. South of Cape Cod, Massachusetts, the water is a lot warmer than north of Cape Cod. This is a direct function of the Gulf Stream. Water in Maine, and further north into Canada, is extremely cold, and even in the summer won't make 15 degrees Celsius in a lot of places. Swimming time is measured in minutes. In winter, survival time can be less than a minute.

However, with training and a plan, you can actually stay in for a while and make it work. Immersion approaches can help, such as wetting yourself down and rubbing yourself, letting your skin become used to the cold water. I find this works reasonably well, but a man's balls are going to try climbing back inside him once you go into the water. Another approach, which I've never tried, is rubbing yourself with grease as an insulator.

I go sailing into November and occasionally capsize. A wet suit, a plan on what I'm going to do, a life jacket, and training work well and I figure I can stay in the water for about 15 minutes without a problem, although I won't be happy. This is a sudden immersion, but I've never had the automatic gasp or anything like that. But even though this is a sudden immersion, I'm mentally prepared for it to happen.

With proper planning, it's very doable to swim across a cave, even with water in the 5 degree Celsius range.

Jim Clark-Dawe
 

WeaselFire

Benefactor Member
Kind Benefactor
Super Member
Registered
Joined
May 17, 2012
Messages
3,539
Reaction score
429
Location
Floral City, FL
Caves in the northeast generally run in the 55 degree (F) range and the water is usually cooler, in the 40-45 degree range. You DO NOT want to swim in it. Yes, practical experience combined with clumsy stupidity. :).

Divers in wet suits can survive for a while, people in normal dress will go 10-20 minutes before they really start to go downhill.

Jeff
 

Averhoes

Super Member
Registered
Joined
Jun 5, 2020
Messages
58
Reaction score
42
The normal advice is that one has 15-30 minutes in 35 degree F. (or 2 degree C) water before exhaustion, or unconiousness (which would lead to drowning) occurs. Obviously, a person will be severely impaired some minutes before they reach the death deadline.

A person in good physical condition would probably have several more "useful" minutes to try to save himself/herself. A person conditioned to cold water would probably have several more useful minutes. But the big ticket is an insulated wet suit or similar garment. It can dramatically increase survival time.
 

angeliz2k

never mind the shorty
Super Member
Registered
Joined
Feb 24, 2008
Messages
3,727
Reaction score
488
Location
Commonwealth of Virginia--it's for lovers
Website
www.elizabethhuhn.com
I'm surprised no one has mentioned the Titanic. Though most people had life jackets, anyone who went into the water was doomed because of the cold North Atlantic. As I recall (and don't quote me on this), those in the lifeboats said that it took something like thirty to forty-five minutes for the clamoring of the people in the water to go silent. The North Atlantic was probably colder than a cave in the North East, but I think it would be in the same ballpark.
 

Duncan J Macdonald

Plotting! Not Plodding!
Super Member
Registered
Joined
Feb 12, 2005
Messages
1,882
Reaction score
455
Age
66
Location
Northern Virginia
From my US Navy experience, water survival times were always published daily in the Plan of the Day. I saw times ranging from days to minutes. Any way, a quick trip with Dr. Google gave me this table:

Expected Survival Time in Cold Water

Water Temperature
Exhaustion or Unconsciousness in
Expected Survival Time
70–80° F (21–27° C)
3–12 hours
3 hours – indefinitely
60–70° F (16–21° C)
2–7 hours
2–40 hours
50–60° F (10–16° C)
1–2 hours
1–6 hours
40–50° F (4–10° C)
30–60 minutes
1–3 hours
32.5–40° F (0–4° C)
15–30 minutes
30–90 minutes
<32° F (<0° C)
Under 15 minutes
Under 15–45 minutes
 

Matchu

Super Member
Registered
Joined
Jan 19, 2014
Messages
106
Reaction score
13
Website
www.drysailorboy.wordpress.com
If I was impatient, writing a piece of fiction, I'd spend an evening researching the dreadful sinking of the Estonia in the Baltic sea.

This is 'not specific,' but you will find the accounts, in the aftermath, of athletic & strong swimmers swimming with great determination -and surviving about half an hour - while fat people floating in an immobile state survived the hour toward helicopters' arrival, some version of that...truth...
 

sphynge

Super Member
Registered
Joined
Dec 27, 2020
Messages
51
Reaction score
8
Location
North of Confused
Echoing the above with just a little more detail - you’re told about 45min in the 45F SF Bay, BUT it highly depends on your fat level and conditioning to it. There are people swimming from pier to Alcatraz. We are also told that Alcatraz featured hot showers and heating precisely so that runaway prisoners would have a lower chance of survival should they decide to go for the dunk.