Levees are broadly classified as either urban or agricultural because of the different requirements for each.
Agricultural levees provide protection from flooding in lands used for agricultural purposes.
Sublevees encircle areas landward of the main levee that are flooded, generally by capturing seepage water, during high-water stages thus counterbalancing the hydrostatic pressures beneath the top stratum. On the main stem of the Mississippi River, there are approximately 1,602 miles of levee in place. The sketch below is a typical cross-section for Mainline Levees within the Memphis District. In many instances this typical section is modified to include features such as berms , relief wells or cutoff trenches .