Lakes

Lake Okeechobee, which means “big water” in the Seminole Native American language, is the largest lake in the southeastern United States and the second largest lake within the contiguous United States.
First of all, plants naturally grow in and around lakes. Maybe you're asking about a lake that is being choked off by too much algae. In many cases, humans are responsible. Actually, these lakes are being fed too much food for plants!
The largest U.S. lake west of the Mississippi River, Great Salt Lake is about 75 miles long, and 28 miles wide, covers 1,700 square miles, but has a maximum depth of only about 35 feet. Great Salt Lake does not drain out to any ocean.