Four kayakers (John Grover, Tony Powell, Bret Franson, and Jerry Fant) were paddling at Longhorn Dam, a popular park & play wave in Austin, Texas. LCRA typically has scheduled daily releases of thousands of cfs during the late Spring and Summer months, in order to support agriculture downstream. During these releases, a ledge downstream of the dam forms a 50-yard-wide surfable wave-hole combination. At high release levels (4000 cfs, for instance), the wave is difficult or impossible to enter from downstream, so paddlers will typically paddle upstream of it, wait behind one of the pillars of the dam for a surge bubble from the dam to form, then ferry off the end of the pillar at a 20-30 degree angle in an attempt to catch the downstream edge of the bubble. This requires precise timing, however, or the paddler will catch the lateral edge of the bubble, which will push them back toward shore instead of into the wave.
In order to increase the chances of catching the downstream edge of the bubble, some paddlers will ferry out between bubbles and try to position themselves downstream of a new bubble before it forms. Grover was apparently using this technique. After waiting for the calm water between bubbles, he took a couple of well-placed strokes to ferry into the current. The bubble reappeared underneath him. Having surfed this wave hundreds of times before, he assumed that the swell would push him into the wave. Instead he was pulled back into the dam release gate. In his words, “Once I fully realized just what happened, I knew that I was in for a major beat-down. There was no paddling out.”
Fant and Powell were waiting upstream of the wave for their turn to surf it, so they saw Grover get sucked in (Franson was exiting the wave at that time.) Fant and Powell immediately informed Franson of what had happened, and the three jumped into action. The paddlers had throw ropes, but based on their swiftwater rescue experience, they did not feel that the ropes would have been effective. The gate in which Grover was being recirculated is 100 yards from shore, far too great of a distance for a shore rescue, and the paddlers were rightly concerned that, due to the lack of anchor points, a river rescue could potentially pull them into the hydraulic as well. Furthermore, they could not see Grover being recirculated, so they had no sense of whether a rope might have made his situation worse. Powell paddled to shore and called 911. Franson and Fant paddled as close as they could, in hopes that Grover would be flushed out. After watching in horror as their friend recirculated for over five minutes, they finally saw him resurface and break free of the hydraulic. He was out of his boat (which had been "folded over like a taco") and without a helmet and some of his clothes (which had been ripped off by the hydraulic.) Grover was barely conscious, and Franson swam him to shore. About this time, three ladder trucks, four ambulances, two Search and Rescue trucks, one inflatable craft, one helicopter, and several Austin Police cars had arrived. First responders went to work on Grover within 15 seconds of him reaching the shore. Chest compressions were performed, and he expelled a great deal of water.
Grover later explained that he was somehow able to catch a couple of breaths during the ordeal. At one point, he rolled into a ball and got pushed to the bottom. He was able to push off the bottom and break free from the hydraulic.
Source: Eyewitness accounts
Analysis: Based on accounts from the paddlers at the scene and from other local boaters who have studied the dynamics of the surge bubbles from the dam, it seems that there is always a small-but-significant risk of catching the upstream edge of a newly-formed bubble if a paddler ferries out between bubbles. The bubbles are unpredictable and may appear farther downstream than the paddler anticipates, or the paddler may simply misjudge their location in relation to them. Grover was apparently using the same technique that he had always used to enter the wave at this level, but due to a miscalculation or bad luck or both, he found himself upstream of the boil line when the new bubble formed. The bubble thus submerged his boat and pulled it into the dam. Within the local paddling community, there are stories of this happening on at least two other occasions, although no details of those incidents are known.
The risk of this can reportedly be mitigated by waiting until the bubble forms and ferrying out downstream of it, but this also requires precise timing and good boat control in order to avoid missing the wave entirely. Still, however, it seems that missing the wave is preferable to risking a potentially deadly encounter with the dam. Grover had extensive whitewater experience. A paddler with less experience likely would not have fared as well.