You can get a long long way away from the line vertically. If there is current its not like in most caves where it flows parallel to the line either, so you can be blown sideways in the process of being vertically off the line.
tethered or not?
- Thread starter cerich
- Start date
Please register or login
Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
- Ability to post and comment on topics and discussions.
- A Free photo gallery to share your dive photos with the world.
- You can make this box go away
You can get a long long way away from the line vertically. If there is current its not like in most caves where it flows parallel to the line either, so you can be blown sideways in the process of being vertically off the line.
jjones, iinteresting, I'll have to look at that thread.
Richard, I understand the issue with current. I was think more in the way of ice diving in a quarry type setting with no current.
I've never done ice diving and likely never will. Not only is it too cold, but I've heard first hand from someone about a collapse in an ice cave that occurred 30 minutes after divers were out of the water!
Richard, I understand the issue with current. I was think more in the way of ice diving in a quarry type setting with no current.
I've never done ice diving and likely never will. Not only is it too cold, but I've heard first hand from someone about a collapse in an ice cave that occurred 30 minutes after divers were out of the water!
If anyone finds the accident thread here, please include a link. I did a quick search of A & I but didn't find the incident.
Doug. Kevin Ripley was his buddy on the Jodrey from shore in the Saint Lawrence. Accident thread:
The Deco Stop
I believe Kevin is on this board but I can't recall his screen name. I know he doesn't want to re-live that day so maybe just read and ponder.
Otherwise, I don't know if it was ever discussed here or not. But anyone ice diving as if its were a cave needs to read it and decide if its "worth it"
That's why I said untethered ice diving is not universally applicable IMHO (with 2 ice dives ever)
jjones9527
Contributor
It was actually the Kinghorn that they were diving. We'd love to find easy shore access to the Jodrey though. His screen name here is Kevin R and he may not want to discuss this at length, however he would still be a valuable addition to this forum.
Heres my post from a line tender thread here from last year http://www.scubaboard.com/forums/5074791-post41.html
gitterdun
Contributor
The place we ice dive in (the quarry that RJack was referring to), is a little bit different than many other ice diving spots.
For one, the water temperature rarely falls below 37F (it has been holding at 39F, this year), it is near impossible to silt out in the winter, and the visibility can reach up to 200'.
Once winter nears, and the St. Lawrence River temperatures reach 35F, the quarry is where we dive. For us, the risk outweighs the reward, to dive in the river, beyond those temperatures.
This is not to say we are complacent at the quarry. We are just minimizing our risks.
We do our dives with cave diving protocols, but yes.. it is different than cave diving.
I am not sure how to legislate this kind of diving, as it is very different, in different environments.
I have heard of serious incidents, even with tethered ice diving. I am just not sure that single tank diving belongs under the ice. It just doesn't make sense to me. We have also witnessed single tank divers, untethered, under the ice. That really makes no sense to me...
For one, the water temperature rarely falls below 37F (it has been holding at 39F, this year), it is near impossible to silt out in the winter, and the visibility can reach up to 200'.
Once winter nears, and the St. Lawrence River temperatures reach 35F, the quarry is where we dive. For us, the risk outweighs the reward, to dive in the river, beyond those temperatures.
This is not to say we are complacent at the quarry. We are just minimizing our risks.
We do our dives with cave diving protocols, but yes.. it is different than cave diving.
I am not sure how to legislate this kind of diving, as it is very different, in different environments.
I have heard of serious incidents, even with tethered ice diving. I am just not sure that single tank diving belongs under the ice. It just doesn't make sense to me. We have also witnessed single tank divers, untethered, under the ice. That really makes no sense to me...
This strikes me as being a somewhat obvious difference, but a (tethered) ice diving cert is pretty quick and dirty with not a lot of academics, in water training or skills with only a couple of dives that tend to be comparatively short, no consideration for or coverage of "lights out" exits, lost line drills, gas sharing, etc.
Even a cavern class is two full days and 4 dives minimum, Intro Cave divers will have 4 days and 8 dives and Full Cave adds another 4 days and a minimum of 8 more dives, and those dives all tend to be at least an hour long and are drill intensive.
So it's maybe 40-60 minutes in the water mostly looking around to get an ice diving cert while it is 4 to 16+ hours of in water training depending on your cave cert, and that does not even touch the in water experience that may be gained between cave certs.
From that perspective, unless you seriously plan to ramp up ice diving training in terms of both duration and intensity, we are not even remotely considering teaching cave styl ice diving. The basic skills are just not there for the average ice diver candidate.
------
Personally, I prefer non-tethered ice diving, but it is true that their are situations where that is a bad idea. Back in the day we used to do drift dives in the winter below a hydr electric damn. The current and turbulence used to keep the ice off that first 1/2 to 3/4 of amile or so before the river was completely iced over. When you did that, you needed to be very aware of where you were. With some experience you could "read" where you were by changes in the bottom as you got farther donwstream, but you also needed to be prudent enough to make sure you were close to the exit side of the river and exiting well before the river froze back over. It was something a lot of us did, but none of us recommended it to new divers or divers with limited skills or limited SA. Not everyone was that thoughtful or that prudent in their diving and we had a deputy drift under the ice to be recovered later that spring several miles downstream.
Similarly, I have been on recovery dives under the ice where a tether was still the way to go due to zero viz - often rooting around in 3-4 feet of very soupy silt on the bottom of a reservoir.
Places where non tethered ice diving include lakes or quarries with decent depth nad good viz. One of my favorite ice diving activities is on larger lakes where only the bays and cove may be frozen over. You enter on a point, tie the lie off in open water then penetrate back under the ice. You also have compass heading for back up, but a line is a sure thing.
I do agree with the sentiment to avoid entering a lake through a gap in the ice along the shore line - any shift in the wind and that gap can dissapear.
Even a cavern class is two full days and 4 dives minimum, Intro Cave divers will have 4 days and 8 dives and Full Cave adds another 4 days and a minimum of 8 more dives, and those dives all tend to be at least an hour long and are drill intensive.
So it's maybe 40-60 minutes in the water mostly looking around to get an ice diving cert while it is 4 to 16+ hours of in water training depending on your cave cert, and that does not even touch the in water experience that may be gained between cave certs.
From that perspective, unless you seriously plan to ramp up ice diving training in terms of both duration and intensity, we are not even remotely considering teaching cave styl ice diving. The basic skills are just not there for the average ice diver candidate.
------
Personally, I prefer non-tethered ice diving, but it is true that their are situations where that is a bad idea. Back in the day we used to do drift dives in the winter below a hydr electric damn. The current and turbulence used to keep the ice off that first 1/2 to 3/4 of amile or so before the river was completely iced over. When you did that, you needed to be very aware of where you were. With some experience you could "read" where you were by changes in the bottom as you got farther donwstream, but you also needed to be prudent enough to make sure you were close to the exit side of the river and exiting well before the river froze back over. It was something a lot of us did, but none of us recommended it to new divers or divers with limited skills or limited SA. Not everyone was that thoughtful or that prudent in their diving and we had a deputy drift under the ice to be recovered later that spring several miles downstream.
Similarly, I have been on recovery dives under the ice where a tether was still the way to go due to zero viz - often rooting around in 3-4 feet of very soupy silt on the bottom of a reservoir.
Places where non tethered ice diving include lakes or quarries with decent depth nad good viz. One of my favorite ice diving activities is on larger lakes where only the bays and cove may be frozen over. You enter on a point, tie the lie off in open water then penetrate back under the ice. You also have compass heading for back up, but a line is a sure thing.
I do agree with the sentiment to avoid entering a lake through a gap in the ice along the shore line - any shift in the wind and that gap can dissapear.
Kevin R
Guest
Interestingly enough, tomorrow is the 4th anniversary of our accident on 18-02-07. The report was pretty detailed although it was not discussed in length on SB, but on Ontariodiving.com and TDS it was. If someone can find it, feel free to post it in here, I dont mind discussing it with open minded divers looking to learn from it. Im not interested in being lectured by south florida ice diving experts however, no offence.
Similar threads
