Last barriers installed less than two weeks ago
The removal of concrete Jersey barriers from atop the Hannibal flood levee is expected to begin this week.
The process of removing the barriers could begin as soon as Tuesday, May 21, said Andy Dorian, director of central services for the city, during the May 16 meeting of the Hannibal Park Board.
"We will probably leave all the sandbags up there (on the levee) until our seasonals and the street department's seasonals start the week of the 27th. Then they will probably get together and start taking off the sandbags," Dorian said regarding the summer labor that the city is hiring.
A combination of barriers, which Dorian said were shipped to Hannibal from across the state, sandbags, filled by volunteers, and sheets of plastic were used to add an additional 2.5 to 3 feet of protection to the city's downtown flood levee. The levee is intended to protect the city to a flood crest of 34 feet.
When a flood crest in excess of 27 feet is forecast for Hannibal, the city is required to raise the level of its flood levee and floodgates. The process of fortifying the levee began May 2 after a crest of 29 feet was forecast.
The river reached a crest of 28.25 feet the afternoon of May 3 in Hannibal.
Even after reaching that crest, which ranks in the top five of the city's all-time flood crests, city workers continued to raise the levee and floodgates out of concern that forecasted heavy rains to the north of Hannibal might generate a follow-up crest higher than 28.25 feet.
The final concrete barriers were added to the north end of the levee less than two weeks ago by street department personnel.
In addition to the street department, the Hannibal Board of Public Works (HBPW) was involved with efforts to raise the floodgates and portions of the levee.
In a memo to the HBPW Board, Heath Hall, general manager of the HBPW, said the river rose so quickly this time that some of the work had to be done by workers in boats.
Steps are being taken to save the pieces of wood that were used for flood protection on the riverfront.
"We have made arrangements to have at least two 40-foot enclosed trailers to store the lumber inside for future use," Hall said. "The gate extensions in particular are cut to fit and took a lot of time to install. We will carefully remove, mark and store them so we can reinstall them more efficiently in the future."
After dropping to 20.41 feet on Saturday, May 18, the Mississippi River has begun to rise again in Hannibal. According to the National Weather Service it will crest at 22.3 feet on Tuesday morning, May 21. The river is forecast to begin dropping again early Wednesday, May 22.