In the previous two posts I talked about currents in the ocean, and how much fun it can be for divers to ride currents. While drift dives can be wonderful, diving in currents also can create situations ranging from nuisances to something bordering on terror. This is especially so when the currents are unexpected.
One kind of current we don't like to encounter while diving is the downcurrent. Divers need to be in control of their position in the water column, and there are few things more disconcerting than to suddenly feel yourself being pushed down unexpectedly by a mass of water.
We ran into this situation one time while diving off West Caicos, in the Turks and Caicos Islands. Most of the dives in the area are 'wall dives' -- that is, along the face of cliff-like dropoffs. In this case, the top of the dropoff begins at a depth of about 20 meters, and the base of the dropoff is something like 1,000 meters straight down.
The walls there are glorious -- completely encrusted with fans, sea whips, and large sponges of many colors. The wall is the underwater edge of the land, and there's nothing beyond but the open water -- deep and inky blue.
It's quite common to encounter large sharks, rays, and other pelagic fish during wall dives, which is a big part of why wall dives are so appealing. On the other hand, since there is no bottom to land on, or even to use as a reference point, buoyancy control is important. (And, I might add, you definitely don't want to drop anything!)
On this occasion, we were drifting along the wall nearly 30 meters under the surface. We were nearing what had been planned as the deepest point of our dive, so we were carefully minding our instruments for air consumption and depth. We noticed that just ahead there were clumps of bushy sea whips that were fluttering downward. I mean not just hanging downward, but fluttering as if water was being poured over them from above. (See photo.)
I paused to take a photo, and Jerry continued along ahead of me. When I looked away from the camera viewfinder and back at Jerry, I saw that he was not just ahead of me, but more than five meters below me as well -- and his bubbles were going down instead of rising up. He was in a downcurrent. As I watched, Jerry made a sharp turn straight out to sea and kicked hard into the blue. The maneuver worked and he escaped the downdraft, and circled back to the wall. We backtracked in the direction we'd come from rather than risk being pushed deeper again.
Some currents are more a nuisance than anything. We recently unearthed a certain batch of photos I had taken in the Red Sea, and had a good laugh recalling what it took to get the shots. It was during a shallow night dive in a sandy area with a lot of patch reefs -- an area we knew to be particularly rich in little critters of the sort that only emerge from their lairs after dark, so I set up my camera for macro photography. When we entered the water we noticed that there was a current that we hadn't expected, but since we had planned a shallow dive close to the boat, we continued.
We shined our lights around on the sand, and sure enough there were all kinds of interesting photo subjects, especially tiny things. That was the good news. The bad news was that the current sweeping across the sand grew in intensity over the course of the dive.
I spent most of that dive on my belly in the sand, sort of slithering along from one tiny subject to the next. As the current picked up, it wanted to flip me over, so Jerry spent most of the dive lying crosswise across my legs to hold me in place while I operated the camera. I'm sure that if anyone chanced upon us we would have made a really peculiar sight, and who knows what they would have thought we were doing! Really folks, it was just teamwork.
The picture at right is one result of our teamwork that night. You might have to click on the photo to enlarge it in order to see the teeny-tiny nearly transparent crab hiding at the base of the larger creature (called a sea pen - a relative of anemones).
Then there are the terror currents -- the ones that are not only unexpected, but so sudden and strong that they can sweep a diver away. The worst experience we ever had with one of those was at the Brothers Islands in the Red Sea, an area known for strong currents. The current we encountered there one July afternoon challenged us to the maximum.
Our boat had dropped all of the divers in our party along the fringe reef of Little Brother, the smaller of the two islands. The boat then continued to a mooring at the very tip of the island. The plan was for a one-way dive, meandering along the reef to where it ended, at the tip. It was one of those dreamy dives where everything was perfect -- the light was good, the visibility was excellent, the lush reef was spectacular, and there was no current.
Jerry and I were the lead pair of divers. The others were strung out behind us in twos and threes in a parade along the reef. At last we came to the tip of the island. Our boat and another were moored there. The other boat, let's call it #2, was moored close to the reef, having arrived there first, so ours was tied up at the mooring a bit offshore. We surfaced, identified our boat, and began to swim toward the boarding ladder at its stern.
As soon as we left the lee of the island we felt the current. We were swimming with our faces in the water, and just as we felt the current we spotted our boat's mooring line, stretched taught and actually vibrating in the current. We could see the bottom of the boarding ladder just below the surface, and underneath it the boat's propellers. The propellers were whirling as if the boat were underway, even though the engines were completely shut down, another indication of a rather strong current.
We barely had time to consider what we were seeing, because suddenly we felt like we were swimming upstream. The closer we got to the boat -- and the farther away from land -- the stronger the current. In less than a minute, we were making no headway at all.
We had begun our surface swim side by side, but since I had the bulky camera rig to push along I began to lose ground. I felt myself really beginning to huff and puff with exertion -- not a good sign. We were now less than 3 meters from the boarding ladder, but just couldn't make any headway at all, even though we are both strong swimmers. It was the most frustrating feeling.
Jerry made a few inordinately strong kicks and finally pulled ahead of me. A few more kicks like that and I saw his hand reach out and touch the ladder just as I ran out of steam and began to be swept backwards by the current.
It's funny how, in times like that, all of the training you've had clicks in and behavior switches to automatic. Realizing in a flash that I was not going to make it to the boat and that I was being swept away, I quit fighting the current, deflated my dive vest and dived under the surface. I let the current carry me nearer to boat #2, and I managed to dive deep enough to swim under the vessel. I surfaced again between that boat and the shore, again in the lee where there was no current.
I still had to solve the problem of how to get back to our boat, but at least I was no longer being swept out to sea. I called out and some of the crew of boat #2 looked over the side. I waved my arm. They waved back and hollered hello, thinking, I guess, that I was just being friendly. I called out again, and when a face appeared at the rail, this time I yelled "I need help." This time they listened while I told them about the current, and that I needed to get to our boat.
Meanwhile, Jerry had made it aboard our boat. The crew were below having lunch, and were unaware of what was happening until Jerry came aboard, breathless. His plan was to get out of his heavy gear, and re-enter the water to swim to me with a line that was tied to the boat at one end. The only trouble with that plan was that by the time he climbed on board and looked back, I was gone. He hadn't seen me duck under the surface, and he had no idea that I had managed to dive under the other boat and had made it to the lee side.
Then everything began to happen at once. The crew of boat #2 finally understood my plight. They threw me a line, and literally hauled me alongside and around their bow. They hailed our boat and heaved a line to the crew, ultimately attaching me to that line so that the crew could haul me across.
While that was happening, the next sets of divers in our party surfaced and started to swim toward our boat -- right into the current, of course, and they were as surprised by it as we had been. Jerry and the crew of our boat rushed to set a long 'current line' -- a strong line fastened to the boat's stern at one end, with a float at the other. One by one, the returning divers now swam to the current line, and one by one they got hauled to the boarding ladder.
The current line should have been set as soon as the boat tied up at the mooring. Why it was not was never explained to us. Nevertheless we all made it, camera gear and all. In order to use his arms to swim against the current, one of the divers did have to drop his camera. Fortunately it was attached to him with a lanyard, so he didn't lose it.
Speaking of cameras, when Jerry tells his version of this story, he likes to wait until someone asks what he was thinking when he turned around after boarding the boat and realized I was gone. He always answers, "I was just hoping she hadn't dropped that expensive camera!"