Recreationists on Lake Chelan have been dealing with an unexpected visitor to its waters this summer. Lake Chelan is largest naturally-formed body of water in mainland Washington State, with a surface area of roughly 5,200 square miles, and there's been no shortage of the woody debris at any of its many corners this summer. He adds that everyone on lake needs to be aware that the debris can create a hazard during their chosen activities. "People really need to be aware of it. Lake Chelan is a very exciting place to be but people need to be cautious.