Surge in shallow water

[Fuzzmutton]

I have been diving in an area that has been experiencing surge lately, which I am not very experienced with, having only 28 dives in all. The max. depth I go to is about 45' but typically I am at about 25'-35'. Sometimes at 35' or shallower I can get "sucked up" quickly unless I grab onto kelp or a rock; on my last night dive I called it because twice I was pulled up about 8'-10' or more and without having a visual frame of reference it took me longer than it should have to realize it and that freaked me out.

Please be nice and don't roast me alive for my ignorance because I really want to learn what I could be doing better. I know the pros don't say, "Nope there's a little surge, I'm not going out today!" so people dive in these conditions and I'm watching my gauge and surroundings like a hawk but even the FISH are getting pulled around. Keep in mind, I'm diving a novice site in slightly rougher conditions than I saw in the summer months.

Fuzz

 

[Charlie99]

Are you sure that it really is the surge that is "pulling you up"?

Watch the fish. They are probably moving back and forth, but not very much up and down. What up and down movement they do have will usually be a repetitive cycle, just like the back and forth horizontal movement is; so they end up going back to the same spot they started.

It is easy to inadvertantly ascend a bit if you lose visual contact with the bottom, particularly if you suck in air and hold your breath a bit, thereby making yourself more positively buoyant.

I don't have any magic suggestions for you, other than pointing out that if you are good at controlling your depth in still water without making any motions, then you will find it easier to maintain a constant depth in surge, even without a visual reference.

Of course, if things are getting really bad due to surge, then you can always stay in physical contact with the bottom. I often use this method for coming through the surf zone itself, where breaking waves above churn up the bottom. The disadvantage of this, though, is that this pretty much guarantees that you will be in a low viz situation, whereas lots of times there is better viz a few feet off the bottom.

 

[uspap]

I could be wrong but if you are getting pulled up 8 to 10 feet that sounds like more than just a little surge. Could it be you are being pulled back or pushed forward 8 to 10feet? You may have to add some weight for these conditions. You were wise to call the night dive.

 

[Jon C]

I would probably never dive if I waited for a surge-free day here in S. California, so one needs to adapt to some extent.

The main trick is to not fight it. If it is surgey, plan on getting moved around. Don't plan on it being a "Photo Dive" and don't go crevice snooping. Also, there IS a point where you do call the dive, but it is usually a combination of things leading to the decision. Sure, I can stay away from the reef to avoid injury, but if the sand is kicked up and vis is bad...what's the point? Often huge surge means huge waves on the exit. I don't enjoy getting tumbled onto shore and becoming a human sugar cookie.

On moderate surgey days, I just go with the flow, keep an eye out for rocks and do what the fishies are doing...enjoy the ride. My macro shots get put off for another day.

Jon

 

[Melicertes]

It is easy to inadvertantly ascend a bit if you lose visual contact with the bottom, particularly if you suck in air and hold your breath a bit, thereby making yourself more positively buoyant.

Yep I'm with Charlie on this one. I'm not sure what you are experiencing but from what you've described you might inadvertently be holding your breath. New divers often either do not exhale fully or hold their breaths when they face conditions they are not accustomed to. This keeps air in the lungs and it will affect your buoyancy. Surge is generally a side to side motion so the sucking up part sounds a little strange to me... I'd say check your breathing.

 

[boulderjohn]

The depths you are diving are the hardest to maintain buoyancy. A few feet change in depth has a much greater effect on your buoyancy there than at deeper depths. It is very easy to change depth a few feet and then suddenly realize you are ascending rapidly. If you are distracted by the surge, it makes it even easier.

 

[renpirate]

The conditions that you mention are fairly common where I dive. However, if the swell is that bad at 35', you should be very careful, because that means it is even worse as you go up through the water column.

There are several keys to avoiding being pulled up. First is proper bouyancy. You can easily get pulled up quickly and then the expansion of air in your bc will accelerate you upwards. This is a good recipe for a lung overexpansion injury.

Secondly, pay attention to the bottom topography. Watch out for areas where there is an upslope to the bottom, or in channels between rock formations, or when going up a rock formation that ends a few feet from the surface. Eel grass and bubbles are good signs of places you don't want to find yourself. Generally, try and stay deep and closer to the middle of a cove and you should be ok.

Good luck and trust your instincts. If it feels scarry, abort the dive.

 

[Fuzzmutton]

I really haven't had this problem until the last two weekends which is why I was not suspecting just a simple buoyancy problem, and because I hadn't really seen surge here before I thought maybe that was the problem. My buddy, who was certified with me said he is experiencing problems too (but not to the same degree I am I think).

It was so funny! I was a dingleberry and did not do my surf entry/exit with my buddy like my OW instructor showed us and when I tried to exit onto the beach, the surf rolled me over, right over my tank! I had sand in places where the sun doesn't shine. How did it get under my wetsuit?! Well, next time I dutifully did the entry/exit as shown, thank you very much.

 

[Melicertes]

There are several keys to avoiding being pulled up. First is proper bouyancy. You can easily get pulled up quickly and then the expansion of air in your bc will accelerate you upwards. This is a good recipe for a lung overexpansion injury.

With all due respect, swell means that the depth above the diver increases as a wave's crest makes its way towards the beach. The trough of the wave would then basically do the revers and decrease the depth of the water above the diver to the surface. This will be felt by the diver's ears and seen on the diver's SPG. I've dived some hairy conditions with some pretty nasty swells and at about 36ft I have myself seen and felt the sudden increase of pressure on my ears as the swell passes overhead and noticed the decreased depth as the trough follows shortly after. It's annoying because with every swell one has to equalize to compensate for the extra water pressure. If properly weighted and even neutrally buoyant at the bottom I just do not see any way for anyone getting "sucked" upwards even in heavy swell or surge conditions unless the diver changes his/her buoyancy. Surge might shift you side to side for some incredible distances in some conditions, swell might play havoc with your perceived depths but get sucked upwards...:shakehead
Check your breathing and weighting (in this I agree with renpirate)

 

[Charlie99]

ReefMongoose, think about how horizontal currents can generate upcurrents and downcurrents when they go over a ledge, hit broadside onto a steep wall, etc. Surge can generate significant up and down movements in some circumstances as it interacts with the small scale topography like RenPirate mentions.

I don't think that is what's going on in Fuzzmutton's case, but it is possible. I'm betting it is the sort of problem I used to have in complete brownout conditions of heavy surf/surge --- losing all visual reference and then not controling my depth due to lack of reference. That the OP was on a night dive makes this even more likely.

A good exercise to try is ascending with eyes closed. It may sound impossible, but after doing it several times I can do a well controlled ascent for quite a ways with my eyes shut. That skill comes in handy when swimming through the brownout conditions around the shore break zone.