Preparing For A Total Silt Out

[LiteHedded]

I've always seen the siltouts coming (like someone else here posted)
so by the time they occurred I had the line in my hand.
when siltouts are especially likely I'm real close to the line anyway.
and closing your eyes does seem to help. the backscatter from a 21w light against the silt is just gonna blind you anyway

 

[brockbr]

I personally got silted out by my buddy in a 3' - 3 1/2' high bedding plane with a clay bottom 4,100' back. We were on scooters (both diving rebreathers) and he hooked a cylinder off the ceiling and dug into the clay floor bouncing free

People like that, and people who use them in areas where scooters have no business being are why scooters are getting banned in so many systems. The silt out eventually clears, even with clay. The big gouge in the floor is basically permanent.

I couldn't agree with you more. One only needs to look at the floor at ~3400' at JB to see the type of damage caused by careless scooter divers.

 

[jeandiver]

You must have been in there before...

The starting part of it , yes

Bean

 

[ShagMan]

Wow, excellent thread!

I have had the fortune (I guess?) of being in the kind of silt-out that is expected. I have silted the same long left passage of gator hole as Dark Eternal has, and I have also silted a long bedding plane that was tight (low) for singles. In each case, I knew it was coming, and I was either reeling or on the line when it happened.

 

[battles2a5]

I found that during basic cave training, the lights-out stuff was some of the more relaxing drills. It's just you, the slow hiss from your regulator as you plod through the skills and get through it. I didn't see what the big deal was.

Fast forward about a month to my first non-training trip. We had done a few dives and I feeling confident (I should have known this was a bad sign). We ran a line into the catacombs behind another team (having not been there, I did not know it is a 1-team passage). About 100ft into it we were slowly surrounded by a wall of silt. Vis went to zero in no time flat. I was running the reel at the time but I couldn't turn around so I had to move forward, feeling the width of the tunnel w/ my fins as I loaded my kicks until I could turn. As soon as I did, I waited for my team get into place we got turned around. Then we exited just like we did in class; touch contact, slow, smooth, and steady.

At first, I just thought "oh ***!", this is the real deal! Then I thought, "Great, the deco stop is going to have a field day with a group of intro divers dying in the catacombs, 100ft from the entrance in 50ft of water". But then things started to come together. I had full doubles, in shallow water, and I had tons of time. My team was intact, everyone was calm (I could hear everyone's regs breathing slowly). So we just lined up single file and followed our training. The only thing that really worried me was that there were two lines in there so there was a risk of entanglement. If there was an entanglement and we had to cut lines, we could have left another team in there w/o a continuous guideline if we couldn't repair it in no vis. Thankfully, we all stayed off the floor and made our exit w/o issue. Once we got out we talked about it on the surface, chalked it up to a learning experience, and went back down the eye.

So I definitely came away with a different appreciation for my training. I also paid much closer attention to the details of my surroundings during my apprentice/full class having been in a real situation and learning what information is useful when the time comes. I also take a lot more mental notes during the dive, keeping track of gas usage during ingress/egress, marking time to jumps, etc. so I have more information to mark my progress in a no viz situation. But most importantly, I take more care in keeping myself out of those situations in the first place.

 

[DA Aquamaster]

Not too beat you up over it, but the catacombs is off the main line and is not an Intro level dive - mostly so other Intro Level divers are clear on that.

You do indirectly bring up one of the issues of Intro level diving, if done conservatively it protects you but also often prevents you from getting real world experience that later gets your attention and focuses you more at the apprentice and full cave levels. Not diving conservatively at the Intro level on the other hand can be a "great experience if it does not kill you" sort of thing and needs to be avoided. In the middle are some Intro level dives that can give you that experience without getting off the main line.

For example, places like downtream Cow Spring with low flow and semi-tight spaces are also subject to silting and can get interesting even on the main line as going in what ever your team kicks up will follow you and with more than 2 or 3 people, a lot can get kicked up.

All in all it is a potentially strong argument for advancing fairly quickly through full cave to gain training and then diving conservatively as you progressively gain experience to match that level of training. You need both without exceeding the limits of either.

------

One thing to consider that has not really been mentioned is the type of silt. Something with larger or heavier particles such as sand will settle fairly quickly as opposed to finer particles such as clay that could hang there for days or even weeks. Same thing with flow. If you have a lot of flow it will clear quickly and the direction matters depending on whether you are entering or exiting with or against the flow.

 

[kidsdream]

This was actually discussed in some detail during my Intro Class (with Johnny Richards).

As long as you are running a continuous line from open water or you are tied in the main line and don't tie in or jump to another line, you are in strict accordance to standards at the Intro Level. I don't profess to be any sort of expert but Johnny suggested that properly tieing to the main line was actually a way to practice a lost buddy scenario in a safe manner. Similarly running a continuous line thru the Ear (or Eye for that matter) and then in to the Catacombs was also a good way to practice running line. Of course a team's comfort and skill must be taken into account.

For the record I have not done either of these in the area of the Catacombs (other than in our class), but an Intro Cert does not specifically preclude these activities.

Not too beat you up over it, but the catacombs is off the main line and is not an Intro level dive - mostly so other Intro Level divers are clear on that.

You do indirectly bring up one of the issues of Intro level diving, if done conservatively it protects you but also often prevents you from getting real world experience that later gets your attention and focuses you more at the apprentice and full cave levels. Not diving conservatively at the Intro level on the other hand can be a "great experience if it does not kill you" sort of thing and needs to be avoided. In the middle are some Intro level dives that can give you that experience without getting off the main line.

 

[battles2a5]

Not too beat you up over it, but the catacombs is off the main line and is not an Intro level dive - mostly so other Intro Level divers are clear on that.

You do indirectly bring up one of the issues of Intro level diving, if done conservatively it protects you but also often prevents you from getting real world experience that later gets your attention and focuses you more at the apprentice and full cave levels. Not diving conservatively at the Intro level on the other hand can be a "great experience if it does not kill you" sort of thing and needs to be avoided. In the middle are some Intro level dives that can give you that experience without getting off the main line.

For example, places like downtream Cow Spring with low flow and semi-tight spaces are also subject to silting and can get interesting even on the main line as going in what ever your team kicks up will follow you and with more than 2 or 3 people, a lot can get kicked up.

All in all it is a potentially strong argument for advancing fairly quickly through full cave to gain training and then diving conservatively as you progressively gain experience to match that level of training. You need both without exceeding the limits of either.

------

One thing to consider that has not really been mentioned is the type of silt. Something with larger or heavier particles such as sand will settle fairly quickly as opposed to finer particles such as clay that could hang there for days or even weeks. Same thing with flow. If you have a lot of flow it will clear quickly and the direction matters depending on whether you are entering or exiting with or against the flow.

I see your point, but we never tied off on the mainline. I was running a reel from the surface at the eye through the catacombs. That is within intro standards as far as I understand them. That being said, and having been back to the catacombs several time after full cave, I don't think the catacombs is the best place for intro divers to master their craft. I wish I had been clued into that before this happened.

 

[Dark Eternal]

Glen - I love the air I have in them, and they trim out pretty well for me however they are heavy. After spending all weekend lugging both 85s and 108s around I have come to dread moving the 108s. It does not change the fact that I think it is worth it though. I also need a bigger wing. My Rec wings 51 lbs of lift is not really enough when diving wet. At 95' in JB I have an awful lot of air in it to stay neutral - it would not have enough lift for a stage tank for sure. In the end I am still glad that I got the 108s though.

Mat - dont blame ya! Ive had to make that hike several times in the last few days.

Classes have been going great - defiantly learning a lot. Wish we did not have to leave tomorrow evening to go back home.

At the depths I was practicing at with my sac (not even all that great - but decent) I probably would have had a good 4+ hours.

 

[Dive-aholic]

Not too beat you up over it, but the catacombs is off the main line and is not an Intro level dive - mostly so other Intro Level divers are clear on that.

The Catacombs is completely within standards as long as you are running a line directly from OW. There are several locations like the Catacombs that remain within standards. The key is not jumping from one line to another. Checking out areas that are not lined is fine as long as being in those areas doesn't violate any other standards. Although it would be tight, you can get 2 divers side by side through the Catacombs.