2018 Highwater Report – By Peter Nimrod

2018 proved to be a busy year for the Mississippi Levee Board. During the Winter months especially in February and March 2018 heavy rainfalls throughout the Mississippi River Valley pushed the Mississippi River above flood stage throughout the Mississippi Levee District. The River crested 6’ to 7’ above flood stage and was 20’ above average for this time of year.

The Mississippi River at Greenville crested at 54.8’ on March 14, 2018 – the 8th highest crest since the 1927 Flood. From 1927 until 2007, a period of 80 years, the Mississippi River crested above 54.8’ at Greenville four times; 1927, 1937, 1973 and 1983. This averaged once every 20 years.  From 2008 until 2018, a period of 10 years, the River has crested above 54.8’ four times; 2008, 2011, 2016 and 2018. This averages once every 2.5 years.

The U.S. Army Corps of Engineers designed and built permanent solutions to eleven (11) underseepage problem areas found during the Epic 2011 Flood. These eleven problem areas were broken into five different contracts totaling $11.3M and installed 187 relief wells and built 20,405’ of new landside seepage berms. All these permanent solutions were completed and in place by the end of 2015. Since then we have had three highwater events which have eclipsed 54’ on the Greenville Gage (6’ above flood stage) and we have had no underseepage issues at any of these locations during any of these major highwater events. These permanent solutions are working and the Levee Board is very appreciative of Congress for providing the money and the Vicksburg District Corps for designing and building these seepage berms and relief wells.

At the same time we were experiencing a major highwater event on the Mississippi River it was raining significantly within the Mississippi Delta. The Steele Bayou Drainage Structure Gates were closed on February 28th at 88.8’.  The riverside crested at 99.0’ on March 16th. The Gates were re-opened March 25th at 95.2’.  At 95.2’ 450,000 acres were flooded on the protected side of the levee. This included 170,000 acres of farmland and 280,000 acres of trees.  This was the 3rd highest Backwater event since the Yazoo Backwater Levee was completed in 1978 only trailing 1979 (96.5’) and 1983 (95.8’).  Low-Water Bridge Road and Goose Lake Road went underwater at elevation 94’.  The Backwater got on the white line of the Hwy 465 pavement at Eagle Lake near Paw Paw Road.

If the Yazoo Backwater Project had been built in 2008, when the Environmental Protection Agency (EPA) vetoed the pump project, they would have prevented $53M in damages this year alone. Since 2008 the pumps would have prevented $373M in damages.  In 2008 the Yazoo Backwater Project would have cost $220M to build the 14,000 cfs Pumping Plant and pay for the 55,600 acres of reforestation.  At this point the project would have paid for itself and would have saved over $150M in damages.  DBJ

Peter Nimrod is the Chief Engineer for the Mississippi Levee Board based in Greenville