DOWN CURRENTS -Any with true real-life experience?

[arkstorm]

• A down current was reported to have swept three experienced divers to 400 feet in Cozumel, eventually resulting in a DCS fatality. It eventually turned out to be a hoax. They claimed it was a down current to hide the fact that they had intentionally planned a dive to 300 feet (and accidentally gone to 400 due to narcosis.)

I recall that story from about 10-15 years ago.

I wouldn't want to relegate the issue of down-currents to a conspiracy theory but there is evidence that many so-called down-current incidents are actually something else.

Cozumel seems to be ground zero. This would make sense given the prevailing current in that channel and the DM's there tend to have it on the mind. However, incidents like the one brought up by boulderjohn require us to be at least slightly skeptical.

Having said that, the question of what to do if caught in a vertical rip, do you move away from the wall or towards the wall...

The concept of laminar flow would suggest moving toward the wall because the friction of the water along the wall would slow it down compared to the layers of water flowing further from the source of resistance.

I would cling to the wall and try to work my way perpendicular to the flow until, hopefully, I got out of it.

 

[bubblemonkey2]

To the poster(s) here questioning the existence of downward currents (really?) in spite of dozens of verifiable firsthand experiences

It is real
Yes we really experienced it

Watch this, including the end

 

[boulderjohn]

To the poster(s) here questioning the existence of downward currents (really?) in spite of dozens of verifiable firsthand experiences

It is real
Yes we really experienced it

Watch this, including the end

I missed the posts that said that down currents do not exist. Perhaps you should show them.

I did see (and make) posts suggesting that some reports of down currents are inaccurate.

 

[MidOH]

Interesting footage at 14:00:

 

[Snoweman]

Interesting footage at 14:00:

I've seen that video of the vortex before. I agree with her assessment that he didn't use his BCD to get out of it.

 

[bubblemonkey2]

Inflating BC is something to consider. But it also increases the bulkiness, volume, and surface area of the diver, which could result in increased difficulty moving against or out of some currents.

If your plan is to stop fighting and just ride it out, then maybe it makes sense to be a big buoy. But this alone might not solve your problem in very localized, recirculating, or very downward currents.

If the current is trapping your bubbles, consider the BC is a just another big bubble on your back. Watch the video again, pay attention to what the bubbles are doing.

Slightly different context, but in notoriously "sticky" recirculating river hydraulics and whirlpools, buoyancy isn't always an escape. The nearby water flows back into the center, which is probably similar to what is happening in the vortex video. "Buoyancy" becomes increased drag, and just sucks you back in. You might have to find an exit toward the far ends of the feature. In the river context, some people even ditch everything--PFD included--and swim for where water actually exits the self-reinforcing feature (often down and under, in that case)

 

[Snoweman]

Slightly different context, but in notoriously "sticky" recirculating river hydraulics and whirlpools, buoyancy isn't always an escape. The nearby water flows back into the center, which is probably similar to what is happening in the vortex video. "Buoyancy" becomes increased drag, and just sucks you back in. You might have to find an exit toward the far ends of the feature. In the river context, some people even ditch everything--PFD included--and swim for where water actually exits the self-reinforcing feature (often down and under, in that case)

Correct. Take whatever breath you can, go to the bottom and push yourself out underneath the vortex.

This wasn't that situation. Small bubbles followed the vortex in this case. A big bubble probably would have provided the lift to get out.

 

[Dan]

33 years of scuba and several thousand dives all over the world, I've never experienced a down current.

Go dive in Crystal Bay (in Nusa Penida, Bali, Indonesia) or Blue Corner (Lembongan, Bali, Indonesia). There were quite a few accidents related to the down current there, as I posted here:

Gillis and Lembogan

Ssearch A&I for Penida. Got it! Thanks! Here’s an interesting one, Bad weekend in Indonesia 2nd diver was caught in a down current in Crystal Bay out at Nusa Penida while doing a Mola Mola dive. It was a female diver from Thailand and unfortunately she is no longer with us. She was found 4...

scubaboard.com

Or in Raja Ampat (also in Indonesia) Last November, a diver died after experiencing a down current as reported here:

Raja Ampat diver death

Just read this article: Turis Asing Asal Amerika Serikat Tewas, Diduga Gegara Diving di Raja Ampat - tribunsorong.com .

scubaboard.com

 

[mike_bayer]

I had a hairy dive up on the north end of Cozumel at Cantarell a few years back with a group of experienced divers on an Aldora boat.

About a minute into the dive we ran into a swirling down current that brought the group down to 100-116 feet very quickly.

We spent the next 6 minutes swimming as hard as we could to get back up to the wall without much progress. Visibility was pretty bad as all you could see was a wall of bubbles in every direction you looked. One of the divers thought his gear failed and dropped his weights. After looking for him for a minute the DM called the dive and we came up after 8 min.

Thankfully he was already back on the boat when we surfaced. We all sucked back about 800 pounds of air in 8 min. The DWM boat at Cantarell had to call the dive as well that day.

 

[KeelsonGraham]

Another Cozumel incident. Bottomed out at 205 ft.

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