No injured cavers recorded.
At about 1 p.m. on Saturday, April 4, Dan McDowell, Tim McDowell, and Ricky Cole entered Porters Bluff Cave in Clarksville, Tennessee. The large entrance of the cave leads to a water crawl about 40 feet long and 3 feet high, walking passage for 100 feet, then another 40-50 feet of crawl before yielding to 1500 feet of walking passage. In this distance the cave stream has about 15 feet of drop, mostly in small rapids and waterfalls in a 200 foot section before the crawls leading out. On the 4th the weather forecast gave a 70 percent chance for light to moderate showers. Beyond the 1500 foot walking section was 20 feet of crawl and more walking. Dan McDowell went to check it out. Three hundred fifty to four hundred feet further he came to a 12 foot waterfall, of perhaps 25-30 gallons/minute. He turned back and five minutes later was with his companions. Almost at once a new sound could be heard - like a train going over the cave. They were wondering if it could be the waterfall when suddenly the pool of water they were standing beside developed a noticeable current!
The group, as one, headed for the entrance. Before they had gone 500 feet, previously still water portions were running with a current. They began to run where the passage allowed. At the stream descent before the entrance crawls, it was all white water.
Just before the crawls Dan McDowell told the other two to wait while he checked to see if the crawls were still passable. He had been making mental notes of high places to retreat to, just in case. Everything was OK and in a few minutes they had made it out, with 15 inches of air space in the last crawl section. The water continued to rise as they exited the cave. Outside it was not raining. They had been in the cave less than two hours.
Analysis: While the group was inside there had been a half-hour rain but it had not been overly heavy. The very rapid rise is speculated by McDowell to be due to a storm sewer entering the cave system upstream.