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The Bonnet Carré Spillway delivered a plume of thick sediment to Louisiana’s Lake Pontchartrain in mid-May 2011. Taken on May 17, 2011, this astronaut photo shows a muddy plume in the lake, as well as the sediment-clogged Mississippi River meandering through the city of New Orleans. Water flowing through the spillway into Lake Pontchartrain is also muddy brown.

The Bonnet Carré Spillway, Morganza Floodway, and breached levee near Cairo, Illinois, all diverted some of the flood waters from the Mississippi River in the spring of 2011. The diversion measures aimed to lessen the damage caused by an unusually severe spring flood season.

The Advanced Hydrological Prediction Service (AHPS) of the U.S. National Weather Service reported that the Mississippi River at New Orleans reached 17.05 feet (5.20 meters) at 9:00 a.m. CDT on May 20, 2011. This was just above the flood stage for this location, of 17.0 feet (5.18 meters), and well below the record flood level of 21.3 feet (6.5 meters), set in 1922. The Mississippi River at Baton Rouge, meanwhile reached 44.71 feet (13.63 meters) at 9:00 a.m. CDT on May 20, the AHPS reported. This qualified as major flooding for the Mississippi at that location, but it was below the record flood level of 47.3 feet (14.4 meters) set in 1927. Mississippi River water levels were projected to remain fairly steady at both locations through May 25, 2011.

Astronaut photograph ISS027-E-32535 was acquired on May 17, 2011, with a Nikon D2Xs digital camera using a 180 mm lens, and is provided by the ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Center. The image was taken by the Expedition 27 crew. The image in this article has been cropped and enhanced to improve contrast. Lens artifacts have been removed. The International Space Station Program supports the laboratory as part of the ISS National Lab to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. Caption by Michon Scott.