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mudshark
04-21-2008, 23:14
The latest Alert Diver issue from DAN had an "article" on dealing with upwellings and rapid ascents. The problem is the piece was an anecdote on the experience of a couple of divers caught in an upcurrent and the post dive aid one of them received. The lesson is "be prepared".

What the article doesn't talk about at all is how to avoid this in the first place or what to do if you're caught in an upwelling or downcurrent. Years ago a friend was caught in such a situation in the Galapagos and it scared her so much that she hasn't dove since. How can I avoid this situation?

Thanks to all.

Marcus
04-21-2008, 23:42
Even after reading about these scenarios, I'm not sure what me and my wife would do if we encountered them. Not always an easy situation.

fisheater
04-21-2008, 23:58
I've read that these usually occur on a wall, when the current hits the wall and "rebounds" up.

The advice I've seen is to swim away from the wall, until the current subsides. Then, do an open water controlled ascent. Basically, act like it's a vertical rip current.

Anyone have any personal experience with this?

frogman159
04-22-2008, 07:57
Although I've never experienced, I've read that these current are fairly narrow and near the wall. Swimming away from the wall is usually the 1st advice.

Sounder
04-22-2008, 11:08
Currents like this are common in the San Juan Islands at the north end of Puget Sound. Currents can go several different directions throughout the course of 1 dive depending on the structure around you. Having rock solid buoyancy control will enable you to make the necessary adjustments as they hit. In the event that they're REALLY strong, you do whatever you can to manage them... which can include blowing out/exhaling as much as you can when truly being "ripped" toward the surface... ideally, we avoid diving in currents like this.

frogman159
04-22-2008, 21:56
which can include blowing out/exhaling as much as you can when truly being "ripped" toward the surface... ideally, we avoid diving in currents like this.


This is the only thing in diving that scares the hell out of me, either being ripped toward the surface or being sucked into the abyss. Like this thread:

Deadly Down Current - ScubaBoard (http://www.scubaboard.com/forums/near-misses-lessons-learned/211115-deadly-down-current.html)

msprzeor
04-24-2008, 02:32
Currents like this are common in the San Juan Islands at the north end of Puget Sound. Currents can go several different directions throughout the course of 1 dive depending on the structure around you. Having rock solid buoyancy control will enable you to make the necessary adjustments as they hit. In the event that they're REALLY strong, you do whatever you can to manage them... which can include blowing out/exhaling as much as you can when truly being "ripped" toward the surface... ideally, we avoid diving in currents like this.

I can attest to this! It was quite a rollercoaster on a few of our dives up there. Sure was fun though- if not a little scary at times!

CODMAN
04-24-2008, 06:56
Knowing the local currents it the first thing that comes to mind! Thus the importance of a good guide or at least getting good info from the locals about the currents! If you know you might encounter these types of currents in the area you are diving, that's half the battle right there!!!!

Personally, I'd avoid diving an area, or a time frame when important upwellings or down currents are present (if they are tide dependant).

Just my 0.02$

Largo
04-24-2008, 09:17
A good local divemaster is worth his weight in gold.