The US Coast Guard and the National Park Service both have a presence on Lake Mead, not to mention thousands of boaters and shoreline recreationists who would report anything suspicious. read more
"The Hoover dam is one of those miracles of the modern world that almost defy explanation. When you stand next to it, the size is unbelievable. It is more than 700 feet high (imagine a 70-story building). The top of the dam is more than 1,200 feet long. read more