After getting his leg trapped underneath a rock in a waterfall and becoming stuck in 60-degree water for more than an hour, Johnny Napierkowski said he’s learned to be more cautious while swimming. “I thought it was safe, and it wasn’t,” he said. “It was a hard lesson learned, but it’s learned.”Escaping the heat with four friends and his little brother, Napierkowski went swimming at Dougan Falls along the Washougal River on Monday evening. They reached the popular swimming spot about 7 p.m., when temperatures hovered in the mid 80s. The 19-year-old from Washougal saw one of his friends slide down the rocks of the area’s lower waterfall. It looked fun, so Napierkowski went after him. “Right when I went down it, I turned, and my right leg got stuck between a rock and the pressure of the water,” he said. Napierkowski was dealing with hundreds, possibly thousands of pounds of water pressure trying to basically fold him in half, said Firefighter Bill Dunlap. He coordinates Fire District 6 firefighters who are part of the county’s technical rescue team, and helped with Monday’s rescue.