San Juan - Not Just Another Downwelling

[robint]

Jen, good going on all of you. Sounds pretty terrifying and you all dealt with it just fine.

The only time I came across *mental* currents it was all I could do to cling with both hands to the wall. Not much would convince me that there is a better course of action so I would definitely back your course of action - and add extra gusto for blowing off it to head with the current. That must have been a difficult decision.

Was your dive site in a channel by any chance?

J

I'm not Jen, but I can answer...
cozumel mexico... northwest end of island, wall dive


robin

 

[bsee65]

Is there any predictability on that current at all? For example, is there a point in the tidal cycle at which it is most powerful?

 

[InTheDrink]

I'm not Jen, but I can answer...
cozumel mexico... northwest end of island, wall dive


robin

You can still get walls in a channel. I was just curious.

Thx,
J

 

[DandyDon]

You can still get walls in a channel. I was just curious.

Thx,
J

I don't see any need for apologies; many divers on SB don't know much about Cozumel, and too I had no idea where Erewhon was - and still don't know what you mean by that, but anyway.

As many times as I've been to Cozumel, I'd never been up to the northern sites; got that on the list for my next trip - depending on the weather. The first post gave some location info but I'll add some general info that may help even tho I have not dived the sites.

Cozumel is indeed on a channel separating it from the Yucatan peninsula of Mexico, where Cancun is located...

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With the site mentioned being on the north end of the channel nearly...

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The general current in the Cozumel channel is from south to north as the North Atlantic Gyre passes by it on both sides...

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With many exceptions! Shore eddies often push divers the other direction, or even change during a dive, and conflicting currents on a wall can create up and down currents. I've been pulled off the top of a wall that was planned as a shallow reef dive, wondering what the hell I was doing at 100 ft deep alone and my pony bottle back on the boat. :silly:

Is there any predictability on that current at all? For example, is there a point in the tidal cycle at which it is most powerful?

It's not like the tidal currents of the San Juan islands (similar name, different place) in Puget sound. There are some oceanic phenomena following a full moon (the name escapes me) but I suspect what happens at the north end of this channel probly varies a lot with how the Gyre comes back together.

Hope that helped some...?

 

[Cathy Church]

You mentioned in your story that the others divers were deeper and away from the wall, but that they got in the boat before you did. Does that mean that they escaped the current faster by getting away from the wall, and thus surfaced more readily while you were still trying to clutch the wall at its worst point?

I would still vote for not struggling to return to the point of greatest current where I got sucked down to begin with. Clawing your way up a reef into the current often uses up too much air. I would prefer to relax until I got to the other corner, if one is coming up and ducking into the lee of it. I like to follow the path of least resistance, fighting only to avoid getting too deep until I could finally ascend.

I would also highly recommend to everyone that they not look at their cameras until they have assessed the situation they have just dived in to. I have watched many a diver get carried away, or sinking to deep water while trying to set up their cameras.

Thank you for the great details--it gives us all a good chance to consider what the thought processes are.

 

[all4scuba05]

Kinda what I was wondering. The guy you couldn't help and was further away from the wall made it onto the boat before you? Did I read that right?

 

[JenLoves2Dive]

Thanks Kathy. It was in my thinking process and thanks for mentioning about fiddling with the camera on my descent. I definitely gave it much more thought, however, after the fact!

I would say Matt was about 75 feet away from me. Not sure when he got back to the boat but I am pretty sure it was after the others as I recall him saying he gave an attempt at a safety stop but was still bouncing up and down a bit. I saw the other divers with the DM (Gabi), and I am not sure of their depth but I was already on the wall so I am going to guess that they were about 50-60 max. Yes, they were first in the boat, with the other gal that got to the surface first.

Agree about using air going up the wall but I was very closely monitoring my air consumption and none too eager to go back into the downwell. I was working my way up and north at the same time.
Reading the comments and also the article on what to do when getting caught in a downwell well help me tremendously should and when that happens again.

BTW, guys. I can not stress enough, the importance of diving with a SMB (surface marker buoy) AND a reel when diving in current! It's really simple to learn and you can practice using it on your safety stop. It IS important to learn how much air to put in depending on your depth and know how much line you have. It's a whole lot more trickier deploying one at 60 feet.