Massive rainfalls towards the end of April, 2011, have increased water levels along the Ohio and Mississippi Rivers, bringing them to record level highs. Flood waters have inundated homes, businesses and agricultural fields throughout the region.
The U.S. Army Corps of Engineers have already broken the levees near the confluence of the Ohio and Mississippi Rivers, to protect Cairo, Illinois, flooding the Birds Point-New Madrid Floodway. Nevertheless, a mandatory evacuation of the city of Cairo was still in effect at the time of this articles publication.
The top image was taken by the Landsat-5 satellite on May 3, and shows the confluence of the two rivers and the subsequent flooding of the New Madrid Floodway. The bottom image is a comparison image, taken at normal spring levels in 2010.
According to the NASA Goddard Space Flight Center, flooding similar to 2011’s occurred all the way back in 1927, which saw the U.S. Army Corps of Engineers build several floodways to protect populated areas. This included the creation of the New Madrid Floodway. “The 1927 floods showed that no levee system could contain the mighty Mississippi River during big floods. 2011 marks the first (and only other) time since 1927 that the New Madrid Floodway has been used.”
“This is the flood that engineers envisioned following the 1927 flood,” said U.S. Army Corps Mississippi Valley Division Commander Maj. Gen. Michael Walsh in a May 2 news conference. “It is testing the system like never before and now is the right time to activate the floodway.”
By opening the floodway, the Corps intended to relieve pressure on the entire river system, hoping to avoid a repeat of the 1927 disaster. “Making this decision is not easy or hard—it’s simply grave—because the decision leads to loss of property and livelihood—either in a floodway—or in an area that was not designed to flood,” Walsh said.
Further south along the Mississippi River, water levels have risen to 46.68 feet (14.23 meters) at Osceola, Arkansas, and 46.14 feet (14.06 meters) at Memphis, Tennessee. At both locations, the Mississippi is in major flood stage and expected to continue rising.
The above image was taken using the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’sAqua satellite on May 5, 2011, and shows in the top image flooding along the Mississippi River. The bottom image was taken a year earlier.
There has also been flooding, amidst many other locations along the Mississippi and Ohio Rivers, along the confluence of the Ohio and Wabash Rivers, Illinois. The images below were taken by the Thematic Mapper on NASA’s Landsat 5 satellite on May 3, 2011, and are compared with an image below taken on April 14, 2010.
By April 30, floods had already blocked many roads, according to the Evansville Courier & Press. Residents had already started moving their belongings to higher ground, if not leaving altogether. On April 30, the Ohio River was forecast to crest on May 2 at the J.T. Myers Lock and Dam at just over 54 feet (16 meters)—the highest flood waters since 1950 in some rural farmlands. The river was predicted to crest on April 30 at 46.4 feet (14.1 meters) in Evansville.
According to the Advanced Hydrological Prediction Service (AHPS), the Ohio River rose to 46.78 feet (14.26 meters) at Evansville, and reached 56.94 feet (17.35 meters) at J.T. Myers Lock and Dam on May 5, 2011. The crest at the Lock and Dam was the highest recorded since 1937. Meanwhile, the Wabash River rose to 23.67 feet (7.21 meters) at New Harmony (north of the area shown here)—the highest water level since 1943.