One Is None, Two Is One
I first heard the phrase “one is none, two is one” as a private in the United States Marine Corp going through basic infantry training school. It’s a theme well suited for almost any situation in life, very much including scuba diving and boating. Which brings me to the topic of scuba diving off your own or your buddies boat, not a professional charter. Reality is more time than not you will be unable to find a person to sit on your boat while you’re in the water diving. A two tank dive off of Clearwater, Florida in the Gulf of America is an all-day event. You have to travel at a minimum of 10 miles offshore to be in 40 feet of water. Let’s say you have found someone to tend the boat while you are underwater, is that person a capable captain? I get it, anyone is better than no one. But for the purpose of this writing, we will assume your boat will be empty while you and your partner are in the water diving.
So, let’s look at some ways we can mitigate exposure or risk. Basically, the theme is at every connection point you have redundancy. You will need 200 feet of a high-quality anchor line with a stainless-steel thimble suitable for your boat. It’s a lot of rope but you will need it to achieve the proper anchor line scope. A 25lbs grappling hook anchor made of iron and steel with aggressive flukes that will not bend with 5 feet of heavy-duty chain. Since you will be diving “structure” you will need to anchor in structure. A Danforth anchor, although great for sand, is nearly worthless in this scenario. And lastly you will need several heavy-duty stainless steel “screw” type shackles, along with several heavy-duty locking carabiners.
One is none, two is one. We will connect the grappling hook anchor to the chain with 2 heavy-duty stainless steel “screw” type shackles. Then you connect the anchor line to the chain by using 2 heavy-duty locking carabiners. The carabiners go through the thimble of the anchor line and through a link in the chain. Your anchor line is now ready to deploy.
With your boat positioned over your intended structure (dive site), lower the anchor to the seafloor and tug the anchor line until it “sets” into the structure. Once you feel the anchor “set” feed out enough line for a proper scope for your sea conditions. Now tie off the anchor line to the bow port cleat and then keeping tension on the line, tie it off again to the bow starboard cleat. As you are suiting up make sure the boat is not slipping and that you are being firmly held. Enter the water and descend down the anchor line. When you reach the anchor carefully inspect its placement within the structure and adjust if necessary, making sure of its steadfastness. Now all connection points from the anchor to the boat are redundant. You are now in good shape. However, should visibility be on the low side and you want a little more piece of mind, there is one more connection you can make. You can carry a reel with 200 feet of line in it. The same type of reel and line that the cavers use. Tie off the line to the top of the anchor chain. Even if the anchor slips a little, you will slip with it. You can now swim in a 360-degree, 200-foot radius with the knowledge at the end of the line will be an anchor and a boat.
One must be aware you are in nature and your playground is the ocean, it will never, ever be risk-free. However, barring a catastrophic event, this procedure will work as long as your equipment is in good working order, and you achieve redundancy.
We will discuss the process of retrieving the anchor in our next essay
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