My aunt wrote to me about seeing a 'drawdown' of the Mississippi in Minneapolis today. The Army Corps of Engineers opened the floodgates of the dam just below St. Anthony Falls to drain the pool by 13 feet to inspect the underwater outlet tunnels of Bassett's Creek.
Park service rangers explained the goings on from the Stone Arch Bridge as the water level fell to its lowest in 13 years, exposing the remnants of 19th century bridges and dams and perhaps the ghost of Spirit Island. My cousin Brita was even interviewed on KSTP. MPR has a story too which spotlights some of the industrial archaeology of the oldest part of downtown Minneapolis.
From photos on flickr, its amazing to see the river returning to a somewhat natural free flowing level running across the rocks. Which is very low in winter. Without the big bathtub pool created by the dams, the Mighty Mississippi looks here like a feeble prairie river, hardly the mature river it becomes farther downstream.