YD Scuba Diving Forums banner

1 - 20 of 21 Posts

·
Registered
Joined
·
5,966 Posts
Discussion Starter · #1 ·
Imported post

<font color='#0000FF'>Next Saturday will be my first Freshwater dive. It's a submerged village in a reservoir which is at around 300m above sea level. The water temp will be 8ºc-10'ºc. Have a couple questions:

» Roughly how much weight I should remove from my belt? I usually carry 8kg on saltwater.
» Should I be concerned of freeflows or the water is warm enough for this not to happen. I have Oceanic Alpha Octo + OmegaII.
» At 300m, does this make it an attitude dive? I'll read the Cobra manual later but anyway I will doubt very much be diving to the limits.
» Am I damn stupid to do this dive with an 5+5mm wet suit
? I've done dives at 11ºc with no problems with cold so this time I may take an 'shark' undersuit below the wet and a warm thermos flask. The club offered a dry suit but as I've never used one before I refuse to use it for this dive.
 

·
Small, yet perfectly formed...
Joined
·
3,299 Posts
Imported post

[b said:
Quote[/b] (Chris Guimaraens @ Feb. 02 2004,16:03)]The water temp will be 8ºc-10'ºc.
» Am I damn stupid to do this dive with an 5+5mm wet suit
?
No you are insane...
 

·
"hardly ever here"
Joined
·
799 Posts
Imported post

<font color='#000080'>
[b said:
Quote[/b] ]» Roughly how much weight I should remove from my belt? I usually carry 8kg on saltwater.
as a rule of thumb, with normal kit, i'd remove about 4lb (~2kg)

[b said:
Quote[/b] ]» At 300m, does this make it an attitude dive? I'll read the Cobra manual later but anyway I will doubt very much be diving to the limits.
your computer should automatially detect altitude and compensate accordingly... i think - i know my aladin does anyway

[b said:
Quote[/b] ]» Am I damn stupid to do this dive with an 5+5mm wet suit
yes! 8 degrees is pretty cold. reckon you'll manage 20 mins max  
 

·
Registered
Joined
·
330 Posts
Imported post

Hi Chris wicked that sounds like excellent fun . you will need to remove about 2kg of led for fresh water . as for the cold bit it will be cold in a 5mm wet as the deeper you go down the colder it becomes so 10 d at the serface will drop quickly as you decend if you are able to get hold of a 7mill it would be a bit better . where are you doing this village  dive ?? as I am very intersted in doing it as well at a later date as I love that kind of diving
Fiona.
 

·
Registered
Joined
·
3,914 Posts
Imported post

I think you'll perhaps need to set the altitude manually, my old Orca 'puta had to be done that way, I think/thought the Vyper is the same so the Cobra probably would be too,  but I couldn't swear to it
 

·
Snap Happy
Joined
·
2,802 Posts
Imported post

[b said:
Quote[/b] (Chris Guimaraens @ Feb. 02 2004,16:03)]Next Saturday will be my first Freshwater dive. It's a submerged village in a reservoir which is at around 300m above sea level. The water temp will be 8ºc-10'ºc. Have a couple questions:

» Roughly how much weight I should remove from my belt? I usually carry 8kg on saltwater.
» Should I be concerned of freeflows or the water is warm enough for this not to happen. I have Oceanic Alpha Octo + OmegaII.
» At 300m, does this make it an attitude dive? I'll read the Cobra manual later but anyway I will doubt very much be diving to the limits.
» Am I damn stupid to do this dive with an 5+5mm wet suit
? I've done dives at 11ºc with no problems with cold so this time I may take an 'shark' undersuit below the wet and a warm thermos flask. The club offered a dry suit but as I've never used one before I refuse to use it for this dive.
Hi Chris,

1.  Weight: Depends, are you going to be wearing more neoprene to combat the cold?  If yes, then difficult to say how much lead to take off.  If no then the guidance as above should be about right - not wanting to teach my grandmother how to suck eggs but I'd advise a bouyancy check.

2.  What's the ambient temp, generally if the ambient temp is <5 degrees C then I'd advise against breathing off the reg until you do the dive.  This makes a good buddy check doubly important as you shouldn't even breathe your reg to test it. (Increased moisture content in yer reg can cause it to freeze and thus free flow).  At the temps you quote you shouldn't have a problem.

3.  It's not just the altitude which decides if it is an altitude dive or not - what you are concerned with is Atmospheric pressure.  Check the barometer on the day of the dive and check the pressure against your computer manual as what constitutes an altitude dive for that model of computer.  Eg. at Dorothea in Wales, it can an be altitude dive depending on the conditions on the day - if there is a region of low pressure then it can easily be an altitude dive, on a good day (ie high pressure) then not.

Of course all that can be a bit anal.  If in doubt just make sure your computer is set for altitude.

4. I was at Capernwray just after New Year, the water temp was 6 degrees and our equipment froze to the ground between dives.  There was a diving school with shed loads of trainees that day (I'd say easily 8 students to each instructor) - the students were wearing 5mm full-length wetsuits.  I would not want to be a student sitting on the 6m platforms waiting for my turn to do the drills in water of that temp and then have to get out of the water (freezing my nadgers off) to air temp of close to 0 and a bit of a breeze.  

I'd say you'll be ok.

Let us know how the dive goes.
 

·
Just not enough dive time.
Joined
·
9,135 Posts
Imported post

Not knowing which reservoir it may be an idea to take precautions against Weils disease (Rat's urine).

Matt
 

·
A short fat well off crap cave diver. Likes wrecks
Joined
·
15,343 Posts
Imported post

2 KG sounds a bit much to remove seeing as your diving a 5mm suit. The diferance between salt and fresh whith so little added boyancy is negligable. A big puffed up undersuit I would understand but a wet suit?

A weight check is the order of the day

I dive the same weight in Stony as I do in the chanel (4KG) wth a 5mm dry suit and base layour. In the winter I would add 2kg lead for the sea dives to make up for the thinsulate undersuit but I would keep it for fresh water so I could add more air to my suit for warmth in the colder fresh water.  

Any way what are you fussing over perfict weighting for? Your obviously totaly mad to be dooing this in a wet suit. As for altitude setting on the computer?
The cold is far more likley to cause a bend than the altitude so dive WELL within the no deco limits.

ATB

Mark Chase

PS: take twezers with you in case you need a piss after the dive. Your hands will feel like bunches of bananars after the dive so they wont be any good at finding it.

PPS: I am not being critical, this is the voice of experiance talking    
 

·
Small, yet perfectly formed...
Joined
·
3,299 Posts
Imported post

[b said:
Quote[/b] (Mark Chase @ Feb. 02 2004,18:29)]PS: take twezers with you in case you need a piss after the dive. Your hands will feel like bunches of bananars after the dive so they wont be any good at finding it.
and you will also need a magnifying glass to find it because it will be turned inside out due to the cold!
 

·
To dive or not to dive - that's not even an option
Joined
·
2,998 Posts
Imported post

Hi Chris

Timings advice is excellent, best I've read. Anything under 1020mb of pressure on the day is an altitude dive at 300m. You computer may detect the change automaticaly, many do, but check the manual if you like, but it's so close to a normal dive I wouldn't bother, with a 5+5mm wet suit and a shallow dive you won't last that long in the water anyway. You should have taken the dry suit!!

Please let us know how you get on, you'r far harder than me.

James
 

·
Finally not a new member
Joined
·
270 Posts
Imported post

He aint mad hes totally insane and should be certified NOW. Mind there were people diving at Stoney at new year in wet suits.  They survived one dive and I overheard their phone call in which they express great surrpise that they were cold durrrrrrrrrrrrrrrrr theres ice ion the ground durrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr.

Good luck is all i'll say mental pure barking mental
 

·
Registered
Joined
·
1,370 Posts
Imported post

<font color='#FF0000'>Chris forget it go again another day, saw a realy fit bloke last week put on oxygen and carted off suffering hypothermia. after a short dive in a wet suit. the water temp is highly unlikley to be 8-10 its altitude and the fact that it's a large boddy of fresh water will mean that it's more likley to be 3-6 if you must go borrow a dry suit. and use your bc for boyancy. better still stay at home and reed a good dive book. the reserviour will still be there when you are ready. Please no casualties this year.
 

·
"hardly ever here"
Joined
·
799 Posts
Imported post

[b said:
Quote[/b] (louigi @ Feb. 03 2004,09:15)]the water temp is highly unlikley to be 8-10 its altitude and the fact that it's a large boddy of fresh water will mean that it's more likley to be 3-6 if you must go borrow a dry suit.
<font color='#000080'>louigi - remember chris is in portugal, not this country. might be a bit warmer there!
 

·
Registered
Joined
·
545 Posts
Imported post

Chris..
       Well as I suffer the same get wet syndrome you seem to, no matter what the water temp..
Normally after waiting for winter to pass and waiting for the weather patterns to be right, we normally end up doing an altitude dive in Lake Coloridge just to get wet, the last dive we did was in 4 degree water temp ( the Glaciers and mountains directly feed into this lake)..
I have a few tips for you 1st= a 5mm wetsuit ( youll never find your tackle again), so wear polyprops ( thermals) underneath your wetsuit.
2nd= have a spare thermos full of warm water, as hot as you can stand it. it makes an ideal get yourself warm scenario when you open your wetsuit and pour it in, ( Instant gratification ) and helps raise your core temp in a huge hurry
3rd= A lot of hot sugary tea or coffee, Sugary for the instant energy boost ( you'd be surprised how much a very cold dive can sap your energy) and of course instant heat from the coffee and of course " Darn this is bloody good".
4th= I have an Alladin comp, I find If i dont turn it on before I get to the dive site then it adjusts for the alltitude automatically
so all i can say ya Mad bugger
have Fun, and a safe dive and I look forward to reading about it in your dive report
Steve
 

·
Registered
Joined
·
5,966 Posts
Discussion Starter · #16 ·
Imported post

<font color='#0000FF'>Thanks for the comments everyone. Currently the air temp is warm at around 17ºc which is unusual but nice. I've done a few dives in the sea at 11ºc and I was fine for about 45min, so I'm wondering how the difference will be with 2-3ºc less.
The wet suit is Oceaninc Shadow 5mm+5mm two piece, I have an old 7+7mm which I'm tempted to dig out and resuse, the problem it is not nowhere as comfortable as the Oceanic.
The air pressure is a really good point, that had not crossed my mind. On the other hand I will stay well within the limits (if I can).
The idea of a dry suit and using the BCD for boyancy is a very good one, I hadn't thought about that.
In the end I will still try this dive and if I can  feel my 'plums' rubbing against my tonsils and can't take it I'll abort. I'll take some piccies for you lot (of the dive that is)
 

·
The King Of The Divan
Joined
·
1,848 Posts
Imported post

[b said:
Quote[/b] (Gunna Do @ Feb. 03 2004,09:57)]Chris..
       Well as I suffer the same get wet syndrome you seem to, no matter what the water temp..
Normally after waiting for winter to pass and waiting for the weather patterns to be right, we normally end up doing an altitude dive in Lake Coloridge just to get wet, the last dive we did was in 4 degree water temp ( the Glaciers and mountains directly feed into this lake)..
Steve

Without wishing to hijack the thread.... Is there anything to see/ do in Lake C or is it just a case of getting wet for wet's sake?

Simon
 

·
Registered
Joined
·
545 Posts
Imported post

Well surprising youve asked.....
But the actual experience to see in Lake Coleridge is " Weed ", not the smokin kind just acres and acres of weed..
once in the far of distance, I saw an elusive rainbow trout and sadly i did not have any gelagnite with me..
So quite frankly it is the most boring dive i have done (3 times so far) and I sure as heck dont know why I dont stop going
must be some time of sado masochism type thing that i havent worked thru with my therapist..
But at the end of the day it is " cold", but however i do get to see what 5 mtrs of vis is like, and when I am diving at my local spot and the vis is shite i no longer complain I just remeber what it was like to have vis, and recall that it is poss
Steve
 

·
Registered
Joined
·
545 Posts
Imported post

And somewhere i do have some Lake Coleridge underwater pics ive taken..
Just where im not sure, but ill keep lookin.
Ill Pm you when I find them
Steve
 

·
The King Of The Divan
Joined
·
1,848 Posts
Imported post

Steve

Thanks - just checking to see whether it was worth doing. Am over in NZ on the 17th for 2 weeks - North Island only this time. Wedding in Wanganui and then up to Poor Knights and Russell.

But we have a cunning plan for later on in the year (which work need not know about yet...  
). Then hopefully we will be spending quite a bit of time in the South. My fiance is a kiwi (grew up in Napier and uni in Dunedin) hence our plans.

Simon
 
1 - 20 of 21 Posts
Top