Basic dive planning, and a simple dive flag, might have averted disaster when four divers go out but only three return.
The four men were at 15 feet and making their way back to their campsite. They had spent most of the dive in the lake at between 60 to 80 feet, so they were making a long, slow swim back. They were following the bottom contours of the lake, doing their best to stay off the muddy bottom. But Ed was struggling to control his buoyancy at that shallow depth. With each breath, he floated toward the surface. He kept trying to vent air from his BC without much success, eventually having to fight into a head-down position and kick his way back to the bottom. And that’s when the boat hit.
Ed and his buddies loved to dive at the local lake. They would camp out on the shore and dive all weekend long. They had grown up together not far away, took their open-water certification class together and were slowly acquiring new dive gear. Ed had just bought a new wetsuit that week. While it was the same thickness as the suit he normally rented at his local dive shop, it hadn’t been compressed with use. He noticed that he stayed warmer and was able to go a little deeper in the lake, though, and as a result stay down longer than on previous dives.
A light fog rose from the water, and the lake was flat calm as the two buddy teams entered from the shore. The boaters on the multiuse lake hadn’t roused yet, so everything was still quiet. The foursome quickly descended down the rock wall, keeping the dam on their right. Their plan was simple: They would descend to between 70 and 80 feet, staying close to the rocks. When they reached half their gas supply, they would ascend to 30 feet and move back toward their campsite, the rock-wall dam now on their left. When they reached the underwater road bed that ran along the face of the dam, they would ascend to 15 feet and swim the rest of the way in, performing a swimming safety stop.
This dive plan would take them well outside the no-wake zone for boaters. Inside the no-wake zone, boaters were required to use only idle speeds, but outside that area they could move as fast as they wanted. On previous dives, the foursome had trouble with floating dive flags getting tangled in the rocks as they dived along the dam, so they opted to leave them behind this time. They reasoned that they would be well underwater the entire time they were outside the no-wake zone.
Ed had enjoyed the dive, but not everything was perfect. While he felt warmer and more comfortable, he noticed that he had used more air than normal. He had gone a little deeper than the other divers and stayed down a little longer, so he had less air in his tank as he finished the dive.
Ed didn’t hear the sound of the boat propeller churning through the water. He floated toward the surface and was just about to simply swim the rest of the way on the surface when the boater crossed the no-wake zone.
Wanting to get his boat up on plane quickly, the boat driver immediately began accelerating toward the far end of the lake. The rapid acceleration caused the boat’s bow to rise up in the air, shoving the rapidly turning propeller a little deeper. Ed never saw the boat; he only felt it when the hull struck him. He was instantly knocked unconscious and later pronounced dead at the hospital.
Ed changed his gear configuration without thinking about what it would do to his diving. He wore a new wetsuit on the dive, but never performed a buoyancy check. If he had, he probably would have realized that he needed additional weight to compensate for the more buoyant suit.
A typical 80-cubic-foot aluminum cylinder will become positively buoyant as it is emptied — usually 3 or 4 pounds positive. To offset this, most divers begin their dives slightly negative so they end the dive neutrally buoyant. As Ed breathed down his tank, he began to float. At depth, with the suit compressed, it wasn’t a problem. As he neared the surface, the problem became apparent. Ed also had dived deeper and stayed longer than usual, using up more of his air supply. This meant that his tank was just a little bit lighter than it would have been on a normal dive.
The last mistake was the one that could have been prevented. Dive flags serve as a signal to boaters to stay away from the area. The boater had no way of knowing that divers were in the water, much less near the surface. Their bubbles would be breaking the surface, but without some reason to look down, the boater would be looking ahead, not down.
The use of red flags with white stripes is not universal, although it is commonly recognized. Some countries require a blue-and-white Alpha flag. If the group had used a dive flag to alert boaters that divers were in the water, Ed would have finished the dive frustrated, but alive.
Lessons For Life
1. Perform a simple buoyancy check on your first dive after adding a new piece of gear, making a change to your setup or diving in a new environment.
2. Take a few moments to consider how every piece of equipment you might carry (like a dive flag, for example) can be a critical safety item.
3. Use a dive flag, or Alpha flag, when diving in an area where boaters might be present — it can alert boaters to your presence and help prevent a tragic accident. Check with local regulations on the size and design required.
Eric Douglas co-authored the book Scuba Diving Safety, and has written a series of dive-adventure novels and short stories as well. Check out his website at booksbyeric.com.