How to detect underwater current , upstream, downstream

[scubazendiver]

Hi
is it possible to see underwater currents, up or downstreams before diving right into them?
As a new diver I tried to watch as many videos on youtube as possible to get an overview of what awaits me down there.
I saw divers getting flushed away or dragged down, pushed up without being able to foresee it.
What I know is that I should pay attention to waves above if in shallow water or tidals waves which as much as I know are predictable cause I can get information on it.
But how about those invisible traps that suddently flush you down like a toilet? Any suggestions or just have a hook ready at anytime?
Sorry but english is a foreign language to me.


Thank you

 

[tursiops]

You might be able to see particulates moving in the water, or waving/bending-over gorgonians, or fish all lined up facing the current, or visual disturbances (if water of different temps/salinity are mixing). But not always. You need to be aware of such clues, but be ready to respond if you get caught. Best-practice response is to swim sideways to the up/down current; they are usually pretty narrow, so you can swim out of them much easier than swimming against them.

 

[BedHog]

Bring a long string with a small weight on the end. Drop it into the body of water and watch what it does. Will it tell you everything about what's going on 50' below? Probably not. But it's something.

 

[Johnoly]

...But how about those invisible traps that suddently flush you down like a toilet? ...

Usually you let the divemaster lead the group. The will tell you to move up if they see something ahead that is dangerous. As you swim along the reef,,,look out infront of where you are diving and look at the coral fans and plants. Carefully note WHICH DIRECTION they are bending towards. This will tell you which way the current or downwhelling will be going.

 

[ColoDale]

I watch the particles in the water, soft corals and sea fans and the like and fish. The fish in open water will get "blown" around and see if they are finning alot and not making headway.
Before I get into the water I try to know the usual current direction and watch for anything floating on the surface. That is difficult to discern if the boat is also moving/floating.
I can sometimes turn sideways horizontally and see if a current turns me or if I feel a differnt kind of push. Not sure how to explain that one and it takes some practice.

 

[chillyinCanada]

If you see numerous small ripples on the surface but only in certain areas, there's a river like current there.