Daily Archives: May 20, 2011

The Project Flood

When one of my younger sisters was a toddler, she would chant from her car seat as our mother drove across the Fort Pitt Bridge and in view of the Point, “Allegheny, Monongahela, Ohio, Mississippi!” Her multisyllabic nursery rhyme was pretty adorable, and it nailed a fundamental fact of life on Earth: our waterways connect us to seemingly distant places. Growing up so close to three powerful rivers familiarized me with water’s majesty and entertainment as well as its dangers and inconveniences, so the recent events surrounding the flooding Mississippi have been both fascinating and heartbreaking to witness.

Mississippi River Drainage Basin

Mississippi River Drainage Basin, from the Mississippi River Commission

The Mississippi River is the watershed for 41% of the contiguous United States. This year, abundant spring storms in the Midwest have increased the amount of water filtering through tributaries into the Mississippi. All of this water puts enormous pressure on the system of structures that shape and direct the river’s flow. According to The New York Times, “The flood-control system that arose in the wake of [the Great Flood of 1927] has never been put to such a test.

The most devastating river flood on record in the Lower Mississippi  Valley was the Great Flood of 1927. The Mississippi River and Tributaries Project (MR&TP), which includes members of the U.S. Army Corps of Engineers, developed structures to withstand 11% more water than that flood, and refer to that measuring stick as the project flood. While flow levels in the current flood have been breaking records in some areas, they still probably won’t approach levels that exceed the project flood’s.Rising tide : the great Mississippi flood of 1927 and how it changed America / John M. Barry.

Without this infrastructure, an area of 35,000 square miles over Missouri, Illinois, Tennessee, Kentucky, Arkansas, Mississippi and Louisiana would be in danger of  flooding. Widespread damage from major floods from the mid-1800s to 1927 inspired the centralized initiative to manage the river, making it safer for industry, navigation and settlements along its shores. Many of the locations currently in the news are part of this network, including numerous levees, and the Birds Point-New Madrid floodway, Morganza floodway, Bonnet Carre floodway, Lake Pontchartrain, Atchafalaya River and Red River. When water flow upstream exceeds normal levels, this system allows the release of water by opening levees and spillways (also called floodways) to relieve pressure on structures downstream. Unfortunately, farms, communities, and businesses that have built in these spillways can be damaged or devastated by the water. To understand the astonishing amount of water this system is managing and its potential for damage, one only needs to look at some of the before and after photos of areas affected by the water releases over the past week.

An event as multifaceted and with as much historical background as this one is far too complex to cover in one article, but plenty of sources will continue to offer up-to-date information. For updates about Operation Watershed, visit the U.S. Army Core of Engineers New Orleans District’s Facebook page. Also, Louisiana Governor’s Office of Homeland Security & Emergency has been posting images like the one below of communities and wildlife affected by the controlled flooding on its Flickr page. The New York Times features a Q&A series with experts who address questions such as “How much of this disaster is the result of man-made structures?” and  “Why would people build in a spillway?” Also, stay tuned  to Eleventh Stack for future posts about the Mississippi flooding and its many implications for the people who live near the great river.

–Renée

Deer in Water

Enforcement agents from the Louisiana Department of Wildlife and Fisheries responding to flooding in Louisiana captured images of wildlife fleeing water that has displaced them from their habitats. The agents were patrolling Tuesday, May 17 between Highway 190 and the Morganza Spillway, inside the guide levees. Agents report all wildlife that was photographed survived. Photos courtesy of Louisiana Department of Wildlife and Fisheries.

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