This smelly black discharge happened at the base of Niagara Falls over the weekend. It surrounded the dock where passengers board the famous "Maid of the Mist." The Niagara Falls Water Board eventually explained the black sludge had occurred because they had to flush out some filtration basins. They described the black was as "Normal sewer water discharge." Then apologized for causing alarm.
Niagara Falls is really a beautiful place. I'm so glad we can't smell this post.