DIR Ascent Protocol for Drift Dives in Heavy Current?

[Reg Braithwaite]

(Sorry, too early in the morning to compose a pun on the subject of threads drifting from the OP topic)

In the Thousand Islands, most of our local DIRties like to scooter the wrecks, and may do technical deco dives like the Jodrey, so they have different considerations. But when doing no-deco boat dives there, sometimes you are free to drift the ascent (an SMB is obviously a good idea) and the boat will pick you up, and sometimes you must try to ascend the mooring line because drifting with the current will take you into the shipping channel.

Unlike the other thread I posted, I am not discussing a situation with heavy swells, just a strong current that will carry you to a place where you will get a really good look at the props of a freighter that hasn't sunk yet. Either that, or a free ride to Montreal.

What is the DIR protocol for a situation where a free drifting ascent is dangerous? Is it acceptable to hold the mooring line with your hand while maintaining proper trim and depth?

 

[MonkSeal]

There are different aspects of ascent in such situation - don't be focused only to hanging on mooring line. E.g. mandatory return to mooring line requires different gas management then if free drifting ascent is allowed.

 

[rjack321]

The boat is anchored/moored in the river? My first question is why? What is that achieving? Second question, is there a chase boat (RIB, etc)?

 

[shoredivr]

ascend the mooring line because drifting with the current will take you into the shipping channel.

[....] just a strong current that will carry you to a place where you will get a really good look at the props of a freighter that hasn't sunk yet. Either that, or a free ride to Montreal.

The current at some wreck locations in the St. Lawrence can be 3.5 knots or more.

The boat is anchored/moored in the river? My first question is why? What is that achieving?

rjack, the answer is the underlined part: shipping channel, you don't want to be doing a drift under a bag with the big freighters.....

 

[rjack321]

What monkseal said.

3.5 knots You realize you have no choice but to drift that right?

 

[JeffG]

What is the DIR protocol for a situation where a free drifting ascent is dangerous? Is it acceptable to hold the mooring line with your hand while maintaining proper trim and depth?

Yes...you better not break trim while holding onto the line.


LOL

Well, at least the DIR forum is getting some action lately.

 

[Rainer]

We did our T1 class in the Thousand Islands area. For our experience dives, in strong current, it was imperative that we get back to the mooring line. Drifting was a last option, as shooting a bag in the shipping channel would close it. We simply found nooks and crannies in which we could rest for the deco. Was actually a lot of fun. The current was nothing like what we usually experienced in the NE. In any case, still curious about doing drifting deco. Just know it wasn't what we planned for in the TI area.

 

[SparticleBrane]

The current at some wreck locations in the St. Lawrence can be 3.5 knots or more.

How is this measured? Can you provide empirical evidence of this, beyond someone "Gosh that seems fast, I bet it's 3.5 knots AT LEAST!"

 

[JeffG]

How is this measured? Can you provide empirical evidence of this, beyond someone "Gosh that seems fast, I bet it's 3.5 knots AT LEAST!"

I'm not sure what the number is...but its fast.

I did a dive on the Daryaw where we were flags on the mooring line. Absolutely no way to swim against the current.

Henry C. Daryaw - DiveSpot

 

[shoredivr]

3.5 knots You realize you have no choice but to drift that right?

You can't drift it, you'll wind up in a shipping channel.

Options I can see in this kind of current given the large freighters and the coast guard's dislike of drift deco in the shipping channel are:

1 hang onto the mooring line

2 use a scooter if you have one

3 don't do the dive, find another location where you can drift without getting into the shipping channel

#1 isn't DIR, right?

Water temps have dropped a bit since September. Wish I was out diving the St. Lawrence right now.
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