First independent dive

[Shipwreckscanada]

One of my friends will be getting OW and AOW certified this summer with PADI. One of the first independent trips he wants to make is in his own backyard, literally. Because he does a lot of fishing in this lake and uses a depth finder, he tells me that the maximum depth is about 90 feet. In ALL of my diving I have always been were hundreds of other divers have gone before me. So I am a little anxious about this new situation. In addition to a rescue plan, does anyone have advice for me? Is there something that I would need to know so that I can make this outing safe?

 

[NvScubaSteve]

Not knowing much about the site or location a few things come to mind. Plan the dive, and dive the plan (like dive objective, depths, time, air pressure bench marks for descent, turn, ascent, and rock bottom, navigation etc). Also have adequate surface support and if possible a stand-by dive team if possible while diving and a means of alerting surface support (DSMBs) of your dive status and/or problems if they occur. Don't ignore small issues or problems if they occur and discuss with your dive buddy plans for the "what ifs" that can occur. Also have all equipment for low viz / low light diving and plans for a silt out and buddy separation. Stuff like that are a few thing that I would start planning based on your question.

Have fun and dive safe.

 

[TSandM]

Well, if it's a medium to small lake, you probably won't have to deal with any waves or serious current. Lakes, though, can have very peculiar bottoms. I know a friend went to dive a submerged power station in a lake, and they had to abort because the mud was so deep they couldn't walk in it! That, of course, is only an issue if you are diving from shore. But if you are diving off a boat, you have to deal with securing the boat or having a boat tender, and also with how to FIND the boat when you come back up.

If there is a lot of fishing in the lake, you may have a significant risk of running into monofilament, so both of you should have a couple of cutting devices that you can reach with either hand.

Visibility in lakes can be rather bad, so I'd highly recommend having lights to help keep you together and help you communicate.

I sure wouldn't recommend a dive to the bottom of an unknown 90 foot lake as someone's first dive out of OW.

 

[Islandheart]

As others have said, have surface support and back up team ready. The unknown is exactly that, and it can cost you your life.

Poor planning at even known dive sites, have had serious outcomes.

I agree that diving a site like this, for an out-of-the-box OW diver is Not recommended.

 

[boat sju]

Shipwreck,

Do you have a topographic map of the lake? A nice drop off to a hard bottom at about 30 ft or so would probably be a nice dive for you guys. Your buddie's fishing spots are probably also the best dive spots. If this lake is similar to the ones here in Michigan there's probably not much to see between 40 ft and 90 ft and you don't want to be there yet anyway.

Oh yeah : dive flag and a knife. Waverunners and fishing line are probably going to be your two biggest concerns.

 

[DaleC]

I have made it something of a habit to dive undocumented lakes in our region, usually solo, and am currently diving one lake extensively to record it's overall topography (amongst other things). Not knowing your situation, what I do may or may not apply.

I usually dive from shore to a predetermined depth and follow that contour in one direction until I hit my predetermined turn pressure (note the term predetermined), and then backtrack on a (shallower) contour to my starting point. If I am diving the same location I may do this several times at different depths and directions until I get a "feel" for the topography. Like old school wreck divers, I see this as a form of progressive penetration and it works for me. From this starting reference I can then branch out to deeper, longer dives if I want.

Many lakes I dive have very low vis and perhaps the two greatest dangers I see are disorientation and entanglement:

Lake beds may not always slope towards shore the way we think and it is very easy to get completely turned around underwater. One personal example of this was at Pavillion lake where I followed a depth contour that I thought would take me around a small islet. Instead it branched off on a submerged peninsula and I finally surfaced somewhere in the middle of the lake. Long surface swim from somewhere I did not expect to be! Generally though, I dive with a compass and take a bearing before descending so I know which way "in" is. Low vis silt conditions can also sometimes induce vertigo if one fixates on the particles floating by. Don't panic if it happens even though it may be disconcerting - close your eyes and it will pass.

Entanglements are not always rope or fishing line either. In my neck of the woods a major hazard are tree branches that one can swim into in low vis conditions. These can work into hoses or BCD's if you don't catch them quick enough or panic and thrash about. I generally move slowly and at times even sweep my arm in front of me to detect objects before I swim into them though I suggest, if the vis is that bad, you might want to rethink the whole proposition for the time being.

Did I mention predetermined? That should be your guide for the first few dives. Set specific, conservative goals and execute them. As you gain competency, you can set larger, less constraining goals.

Good luck and take it slow...

This video is taken in unusually good vis for this lake, imagine swimming into some of that stuff in low vis conditions... And the question is not what, but who, is in the barrels.

[video=youtube;tmTWlOQjmV4]http://www.youtube.com/watch?v=tmTWlOQjmV4[/video]

Some other stuff I have found:

 

[DivemasterDennis]

Let me add without repeating. IF you opt to do this dive, and I think that if you are reasonable it can be an appropriate dive, I would have you be mindful of the following: First, have at least one shore guy with first aid and a telephone. Next, tell others where you are diving and when you will be back. Then when you finish the diving, call and tell them you are back so they don't worry about you, but also so that, if you don't call, they can alert appropriate authorities. Even in a lake, use a dive flag so your shore guy can track your location and others will know there are divers in the water. Take a good light. It can be helpful in limited viz. In fact, you and your buddy should each wear a tank light as well. If the visibility is under 12 feet, consider a "buddy cord," about a 4 foot cord knotted on the end that you each hold to maintain buddy proximity. Don't tie it on- hold it. Move very slowly, learning the area. Stay VERY close to your buddy at all times. Be sure your equipment is in good condition, and check your air fills before entry. Do a thorough buddy check. Finally, do a short initial dive. Limit both depth and duration to get oriented to a new environment. 30 feet for 30 minutes would be my plan. After a reasonable surface interval, and assuming that conditions were ok, and you and your buddy were ok, a second dive can be a LITTLE more adventurous. Since it is truly a "back yard site, take your time, learn what is beneath the surface, and it may turn into a good local site. Or the vis may suck, there may be nothing to see, and after 10 minutes you may give it up as a bad idea. Be safe, plan well, and have fun.

 

[turnerjd]

I would follow the advice of DivemasterDennis and keep things simple.

If your friend has a boat and a fishfinder do you have a place where you could do a simple shore dive perhaps going no more than 15m down (whats that in feet 45ft?) perhaps even less, but have been over in the boat with the fishfinder on? this will give you a good idea of the bottom contours. Find out what the visibility is like there, and get yourself accustomed to diving there.

Start slowly, shallow and short.
Perhaps take a buddy-Line.
Take lights.
Take a cutter if there is lots of fishing there and a risk of monofilament line.
How about an SMB (permanent not a dSMB).
Have a good plan, and dive that plan.
Have somebody at the surface with an emergency plan. Do you have the number of DAN etc if there is a problem?
Ask other local divers about the site - if they don't dive it, there is probably a reason.
ENJOY your DIVE!

There will probably be poor vis and not much too see, and afterwards you will wonder why the hell you were so determined to do the dive, but that is part of the adventure.

Jon

 

[DaleC]

I am very curious about the last two posts calling for surface support. Really? I suppose it cannot hurt but isn't this a bit like buddy buddy diving. Two trained divers should be able to plan and execute a simple lake dive without it. Not a criticism but also not needed IMO. Shore based surface support without SCUBA can do very little in terms of meaningful rescue. For the first few dives I would rather place my safety "eggs" in the nest of conservative goals and practicing good buddy skills.

I also don't like either buddy lines or towed dive floats. To me they just add task loading and entanglement hazards. A dive float in the general area will achieve the same result though in recreational lakes they may just as easily be used as pylons for jet skiers. If you are in such low vis that a buddy line is required you should really rethink the dive itself and approach it as an independent diver. Otherwise, buddy contact can be better maintained by swimming "side by side" instead of "follow me" single file (which is the worst form of buddy diving I know of). Aim both lights at the substrate ahead and you can keep track of each other by observing each others beam - if it is there, so is your buddy - if it's not, they're not. Move closer or farther apart as required but don't push the envelope; this will allow a good buffer for individual observation while still maintaining mutual contact.

If I were an instructor I would teach only this form of buddy diving and completely abolish/punish/chastise etc... anyone who lapsed into the "follow the leader" style. I have experienced so many buddy seperations this way it's retarded.

 

[boat sju]

Check your local laws. I'm guessing you have to tow a flag in an inland lake that's open to power boats. If you have to tow one keep the line fairly snug. Yes they are a PITA.