Flood control dikes

Flood control dikes (or embankment), levees, and floodwalls are the most common flood protection structures. They are used in areas subject to inundation from tidal flow or riverine flooding, but not for areas directly within open floodways. Levees create a barrier to confine floodwaters to a flood-way and to protect structures behind the barrier. Floodwalls perform much the same function as levees, but are constructed from concrete. 

DDMFC-Department of Dikes Management and Flood Control of Vietnam. 2007. Flood damage reports. 

By contrast, the inland delta of the San Joaquin and Sacramento Rivers shows particularly low values as a result of floods controlled by dikes near the California State Capital. 

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