Here's the caption of the photo Edan posted earlier; I'm still trying to find the exact location in Google Earth. This one connects the lake to the Mississippi through a series of locks and, as the name suggests, is used for shipping.
Originally posted by Edan

Water spills over a levee along the Inner Harbor Navigational Canal in the aftermath of Hurricane Katrina in New Orleans, Louisiana. Fresh floods, fires and looting rode in the destructive wake of Hurricane Katrina, deepening a humanitarian crisis that left hundreds feared dead and sections of New Orleans submerged to the rooftops(AFP/Pool/Vincent Laforet)
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