Flood Fights Activated On Lower Mississippi
High water from heavy rains in the mid-Mississippi Valley area in early April reached the Lower Mississippi River in the second week of the month, triggering navigation restrictions along the middle Mississippi River.
Heavy rains in the first week of April led to numerous flash flood warnings in communities in three states in the Ohio and Mississippi Valleys. Little Rock, Ark., had its first-ever emergency flash flood warning from the National Weather Service. Cape Girardeau, Mo., also experienced severe flooding.
The Memphis, Tenn., area received almost a foot of rain in early April, raising the Wolf River and Mississippi River to minor flood stage of 34 feet at Memphis. The river there was expected to stay at or above that level for most of April. At Osceola, Ark., the river was expected to stay just below 38 feet through April 21.
Due to the high water levels, the U.S. Coast Guard put navigation restrictions in place on the mid-Mississippi River between Caruthersville, Mo., and Natchez, Miss. At Hickman, Ky., the Mississippi River was expected to remain in major flood stage through April 19.
On April 14, the Memphis Engineer District posted on Facebook, “With this event expected to stretch a week or more along the Mississippi and Obion systems, our team remains focused on keeping communities safe.”
At Vicksburg, Miss., Mayor George Flaggs Jr. issued a state of emergency earlier in the month. Emergency officials put up barriers and flood wall gates and said they would closely monitor conditions. As of April 16, the river was expected to crest around 48 feet on April 23.
For the second time this spring, the Mississippi River at the Carrollton Gage in New Orleans has risen above 11 feet, prompting the New Orleans Engineer District to reactivate Phase I flood fight procedures. The Corps also activated Phase I measures near Des Arc, Ark., near the White River. The Corps initially entered Phase I flood fight February 24 and then paused operations when the water level at the Carrollton Gage dropped below 11 feet March 13.
Phase I is a proactive measure that is triggered when the Mississippi River reaches 11 feet at the Carrollton Gage and is forecast to continue to rise. In coordination with the local levee districts and municipalities, the New Orleans District will continue patrolling the levees along the Mississippi River twice weekly until the water level drops below 11 feet at the Carrollton Gage. The increased patrols help ensure the ability of responders to react quickly to any problem areas, like seepage or sand boils, that may develop along the levee system because of the elevated water levels.
All work that may affect Mississippi River and Tributaries levees, which includes transport of heavy loads over the levee, disturbance of grass cover or subsurface work within 1,500 feet of the levee is prohibited when the Mississippi River elevation reaches 11 feet and rising at the Carrollton Gage in New Orleans. Waivers are considered on a case-by-case basis and depend on many circumstances, including surrounding subsurface ground conditions.
Forecasts anticipate the flow rate and stage in New Orleans to approach the trigger for operating the Bonnet Carré Spillway in Norco, La. Historically, the Corps has operated the spillway, which diverts water from the Mississippi River to Lake Pontchartrain, when the flow rate on the Mississippi River in New Orleans is forecast to reach 1.25 million cubic feet per second. Typically, that corresponds to 17 feet on the Carrollton Gage. As of April 17, the Carrollton Gage was forecast to crest at 16.5 feet on April 27.
