Cal and Harry were sitting pretty, ­enjoying a river drift dive in favorable conditions. After pausing for a moment to ­compare pressure gauges and seeing they were good on air, they decided to continue from the small feeder stream into the river and the pool behind the dam. That’s when they got into trouble.

The Divers

Both men were certified, but neither dived regularly. They typically went with friends only to local lakes and quarries. Cal was 38 years old, and Harry was 36. Neither had any known medical issues.

The Dive

Cal and Harry met with three of their friends for what promised to be a unique dive. They planned to make a drift down a local tributary river that fed into a larger one, and end the dive at the confluence of the two waterways. There was a boat ramp where they'd be able to exit the water. One of their buddies left a truck there to take them back to their cars. The group of divers made a shore entry and swam to the middle of the channel in the stream. Once they were all ready, they agreed to descend and began floating with the current, five divers in all. They planned to dive as a large group, but ended up splitting into two groups of two, leaving one diver by himself. The leader of the group brought along a dive flag and let it trail behind them on the surface.
Air temperatures were in the low 90s, water temperatures were in the low 70s, and the divers relaxed in the cool water as they drifted with the current. The tributary river was only 20 feet at its deepest, and the divers hovered around 15 feet.

The Accident

Cal and Harry realized they had entered the main river when the current stopped pushing them along and they had to swim again. The divers checked their air supply and realized they each still had half a tank of air. At that point, they could have swum back upstream toward their exit point. Instead, they decided to explore the main river and the dam pool nearby. There was a hydroelectric dam just downstream from where the stream ­entered the river. They wanted to see the inside of the dam and check out the water intakes. Other divers had told them how large the intakes were and that you could approach them only when they were shut down. They knew it was dangerous if water was flowing through the electric plant, but they were sure they had a few hours before the gates opened. The dam staff ­normally opened the spillway in the ­afternoon, when the demand for electricity was at its highest. They didn’t want to miss this opportunity to share their own ­stories at the dive shop. The two men began making their way toward the dam. They didn’t notice anything was wrong until they got close to the intakes—and by then it was too late. Water was flowing through the hydroelectric plant, and both men were trapped. The other three divers in the group surfaced at the meeting place and exited the water. They waited half an hour for Cal and Harry, and then got nervous something had gone wrong. They searched the surface of the stream and the river, looking for bubbles, but were unable to find any sign of the missing divers. Because Cal and Harry had gone ­beyond the dive plan, no one on the surface knew they were searching in the wrong place. Authorities began on the stream and worked their way toward the river and the dam. They were concerned the divers had gotten hung up on a sunken log along the way. Their bodies were ­recovered the next day. The official cause of death was drowning. Because of high air temperatures and an increased demand for air ­conditioning, the electric authority had changed the schedule for the ­hydroelectric plant. Signs in the area stated no swimming or fishing was allowed at any time because the schedule was subject to change ­without notice. Guards often kept ­people away from the dam on the surface, but there was no way to know divers had ­approached from below. They weren’t diving with a dive flag because it was with the other divers who exited the ­water at the agreed-upon location.

Analysis

Commercial divers routinely dive around water intakes at industrial facilities, but only when the intakes are turned off and secured. They know getting too close to a water intake is dangerous and can be deadly. Since neither diver returned, there is no way to know exactly what ­happened or how they got drawn into the intakes, but both divers were found with no air, entangled in the grates that covered the water access. Typical water intakes around ­electric plants are built in such a way that water can flow all around an obstruction and not trap a diver. They have a cage built around the actual intake that allows water to flow in from the sides as well as the front, minimizing the suction that would prevent a diver from escaping. It is possible these intakes were older or not built to current standards. Regardless of the reason, the two men entered an area they knew was dangerous and paid with their lives. For some people, the appeal of visiting places that are off-limits is exciting, but there are reasons authorities keep people away.

Thanks to Eric Gardner, a commercial ­diver with 36 years of experience around underwater intakes, for his assistance with this case study.

Lessons for life

• Dive your plan. Create an objective for a dive, and stick to it.
• Avoid commercial installations. Without the proper training and equipment, there is no good reason for recreational divers to dive around industrial locations.
• Understand local conditions. When diving around dams, spillways and water intakes in rivers and lakes, it is easy to get trapped and die.
• No dive is worth losing your life. Whether it is a water intake, a cave system or a wreck, don’t enter a place you’re not prepared or properly equipped for.

About Lessons for Life

We're often asked if the Lessons for Life columns are based on real-life events. The answer is yes, they are. The names and locations have been removed or altered to protect identities, but these stories are meant to teach you who to handle a scuba diving emergency by learning from the mistakes other divers have made. Author Eric Douglas takes creative license on occasion for the story, but the events and, often, the communication between divers before the accident are entirely based on incident reports.