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Levee Construction: Proper levee construction is necessary to assure that the project funetions as it was designed and intended during an actual flood event. Construction inspection by a qualified engineer or inspector is required during all major phases of the projeet. Minimum foundation preparation for levees consists of clearing and grubbing the site, but most levees will also require some degree of stripping, Clearing consists of removing all undesirable materials from the land surface such as trees, fallen timber, brush, vegetation, loose stone, abandoned struetures, fencing, and miscellaneous debris, Grubbing consists of removing stumps, roots, buried logs, old piling, paving, drains, and other undesirable subsurface materials, The purpose of stripping is to remove organic topsoil for stockpiling and later use on the slopes of the embankment where seeding takes place, Dewatering of the levee foundation area may be necessary in some cases, The final surface of the foundation area should be scarified to a depth of at least 6 inches prior to placement of the first lift of fill. This will improve the bonding aetion between the foundation and fill. Deficiencies in the embankment construction may have adverse consequences as shown in Table 3, Table 3 Embankment Construction Deficiencies Deficiency Possible Consequence Organic material not stripped Differential settlements; shear failure; internal erosion from foundation eaused by "piping" or through seepage, Highly organic or excessively Excessive settlements; inadequate strength wet or dry fill Placement of pervious layers Allows unimpeded seepage that may lead to internal extending completely through erosion (piping) and levee failure the embankment Inadequate eompaction of Excessive settlements; inadequate strength; through embankment seepage Inadequate compaction of Excessive settlements; inadequate strength; seepage backfill around struetures in the path between structure and material leading to internal embankment erosion (piping) and levee failure Slope Protection: Embankment protection needed on the riverside slope of the levee to withstand erosional forces of stream currents and waves will vary depending on several factors, The design engineer should provide slope protection as needed based on the site specific conditions and streamflow characteristics. See attached figure 2 for typical riprap sections that can be used for slope protection, Special Considerations: Proper consideration must be given to special design features in the event that a pipeline, utility line, culvert, or other type of conduit needs to pass through a levee embankment section, Inadequately designed or constructed pipes and culverts beneath or within levees can cause serious damage to levees, Pressure lines are especially dangerous since 3