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<br />FLOOD FIGHTING METHODS 2003
<br />
<br />6.3A
<br />Page 36
<br />
<br />CONTROL OF LEVEE OVERTOPPING
<br />
<br />If any levee reach is lower than the anticipated high water
<br />elevation, an emergency topping should be constructed to
<br />raise the levee grade to the forecast flood height. Levee
<br />topping may be required at road or stock crossings, low
<br />levee sections, or railroad crossings. The following
<br />paragraphs discuss various methods for increasing levee
<br />elevation.
<br />
<br />Sack Topping
<br />
<br />The most common form of flood control work is the use of
<br />sandbags for construction of temporary walls
<br />(see Figure 7). The use of sandbag walls to increase the
<br />height of a levee section is called "sack topping." The
<br />sacks are laid "stretcherwise," or along the levee for the
<br />first layer, crosswise for the the second layers, and so on.
<br />The sacks should be lapped at least one-third either way
<br />and stomped firmly into place. When properly sacked and
<br />tamped, one sack will provide about 3 to 4 inches of
<br />topping.
<br />
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<br />Figure 7
<br />
<br />7
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