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<br /> <br />methods that can be used for local levee systems and structures. In <br />addition to describing the preferred capping method, a material list <br />must be developed so that in an emergency, supplies can be rapidly <br />ordered. A sample material list is provided in the appendix for the <br />methods described below. These lists may be tailored to suit local <br />conditions and needs. <br /> <br />Notes <br /> <br />Earthfill Capping <br /> <br />Advantages: <br /> <br />" Simple and relatively easy to construct <br />" Heavy equipment may be used <br />" Faster than other methods of capping <br /> <br />Disadvantages <br /> <br />" Very susceptible to wave and runoff erosion <br />" Limited height <br />" Heavy equipment may be difficult to use on soggy <br />crowns <br /> <br /> <br />Eartbfill is a quick and easy method of capping a levee. This <br />method is generally recommended for levees with a crown width <br />greater than 10 feet. if coheSIve matenal, such as clay, IS not <br />available and the cap will be exposed to waves and current scour, <br />this method is normally restricted to heights of approximately 1.5 <br />feet above the crown. Where cohesive materials are available and <br />wave action and current velocity are minimal, heights of up to <br />three feet may be reached. if the crown of the levee is 20 feet or <br />greater in width. <br /> <br />It is best to use heavy equipment to construct an earthftll cap. <br />Scrapers and trucks can work on the levee when it is dry. But <br />heavy equipment should not be used if the levee is soggy and wet <br />or when water nears the top of the crown. In these cases the <br />vibration of the equipment may cause the levee to fail. <br /> <br />If the levee is in poor condition, it may be necessary to use <br />wheelbarrows and hand labor to build the cap. This is an <br /> <br />Page4-4 <br />