Investigation of Underseepage–Mississippi River Levees

Seepage and sand boils landward of Mississippi River levees have been a problem during major high waters. After the 1937 high water, the Mississippi River Commission initiated a general study of underseepage and various methods of its control. Its specific purposes were to develop a better understanding of the phenomena of seepage beneath levees and of factors influencing underseepage, to obtain information pertinent to analyses of underseepage, to develop and evaluate control methods, and to develop formulas and criteria for their design. The studies reported herein include a compilation of past underseepage reports; explroation and geological studies of numerous sites where underseepage was a serious problem in 1937; installation of piezometers at selected sites to measure substratum pressures; field pumping tests to determine the permeability of the sand aquifer; theoretical, model, and prototype studies of relief wells, partial cutoffs, and landslide berms for controlling underseepage; and observation and measurement of natural seepage during the 1950 high water.