Wall dive in unexpected current: What you would do?

[Cave Diver]

I suppose one could drift with a weighted flag (I guess that's common in Florida). We don't do it up here. The boats do an extremely good job of keeping track of bubbles, and our surface conditions (when it is fit to dive at all) are generally smooth enough to make that possible.

I was thinking more along the lines of a large ball (buoy). We've done live drops on wrecks using this system when there is too much current to really anchor in. The shot line is dropped on the wreck, team is live dropped, secures the line, does their dive, then heads back to the line. Last team clears the hook and the teams drift with the line doing deco. If anyone gets blown off the shot line, they shoot their own bags.

Instead of an anchor, you could use a large buoy with a 5lb weight on it and set the line at planned depth. Just kind of let it drift with you along the wall in the current, just guiding it enough to keep it away from things. At the end of the dive, you have a reference to surface, the boat should be close by and has a good idea of the direction and speed of the drift for the whole dive.

 

[MXGratefulDiver]

There is one local dive site where a dive flag is pretty much mandatory ... Agate Passage. It's shallow (less than 30 feet deep except on very high tides), very swift current, and has a lot of boat traffic. But in every other case I know of, you just drift along and come up when you're done. As Lynne said, conditions here are generally calm enough to track divers by their bubbles (except the CCR folks, of course) ...

... Bob (Grateful Diver)

 

[Cave Diver]

As Lynne said, conditions here are generally calm enough to track divers by their bubbles (except the CCR folks, of course) ...

... Bob (Grateful Diver)

Damn CCR folks, always screwing things up!

 

[MXGratefulDiver]

I was thinking more along the lines of a large ball (buoy). We've done live drops on wrecks using this system when there is too much current to really anchor in. The shot line is dropped on the wreck, team is live dropped, secures the line, does their dive, then heads back to the line. Last team clears the hook and the teams drift with the line doing deco. If anyone gets blown off the shot line, they shoot their own bags.

Instead of an anchor, you could use a large buoy with a 5lb weight on it and set the line at planned depth. Just kind of let it drift with you along the wall in the current, just guiding it enough to keep it away from things. At the end of the dive, you have a reference to surface, the boat should be close by and has a good idea of the direction and speed of the drift for the whole dive.

Shot lines are common on wrecks here, John ... but not for drift diving. Among other things, there's bull kelp to consider ...

... Bob (Grateful Diver)

 

[Cave Diver]

Shot lines are common on wrecks here, John ... but not for drift diving. Among other things, there's bull kelp to consider ...

... Bob (Grateful Diver)

Yeah, I thought about the kelp, but wasn't sure how much if an issue that was at the dive sites. Figured on a wall dive it may not be problematic. Until you drift off course...

 

[sambolino44]

Even though we have been practicing shooting the bag and using the line to guide us on a free ascent, I chose not to do that this time because:
- every moment spent deploying the bag would have delayed our ascent
- my buddy clearly wanted to get to the surface as soon as possible
- there was kelp which may have possibly fouled the line
- even though we have practiced shooting the bag from an open water hover, we've never done it in a fast current
- in addition to practicing shooting the bag, we also practice open water ascents with safety stop, and no visual reference

In hindsight, the main purpose of trying to stay in the lee for a while was to just calm down, collect our thoughts, and plan our next move from a less agitated state; it didn't turn out like that. Instead of "arguing", I responded to the thumb by complying. If I could have communicated that it would be better to try to stay close to the wall we may have surfaced closer to the boat. At that time, though, I had a very anxious buddy who wanted to get to the surface NOW! We ended up re-entering the current and flowing away from the dive site before we could even begin our ascent. It turned out OK, but we hope we're learning from it.

One thing I hope we're learning is, when you get excited and anxious, STOP! Slow down, think, look around, assess the situation, make a plan, and communicate. Then, and only then, take action. We had time, we had air, we didn't have to rush into action without thinking.

With my buddy's whistle inside her drysuit and mine still on the boat, it's a good thing we didn't drift that far after all. But I bet they can see that SMB from farther away than they can hear that whistle. At least as it was, with good surface viz and the wind in our face.

 

[MXGratefulDiver]

LOL ... Sam, you and Betty remind me sometimes of when Cheng and I would have an underwater "stress event" ... reading our respective dive logs afterward, you'd swear we were on completely separate dives ...

... Bob (Grateful Diver)

 

[TSandM]

I know just what you mean, Bob. I swear, the two people who are least likely to understand one another underwater are the two who live together on land!

 

[gypsyjim]

Friends say it is quite amusing to "listen" to Colleen and myself argue U/W! If a man and woman have trouble understanding each other, and communication on dry land, being U/W sure won't make communicating any less difficult!