People living in valleys or on flood plains next to earthen dams or levees are susceptible to sudden flooding. Earthen dams are usually built across rivers to dam them up. Levees, on the other hand, are made alongside rivers to keep them from spilling over. However, both can fail in the event of an earthquake, internal erosion, poor engineering and construction, or avalanches. The most common cause of failure, however, is too much rainfall.

When a region experiences heavy rainfall, the water behind a dam or levee builds up and flows over the top. This will wash away the upper portion of the barrier and carves out deep grooves. The dam or levee will eventually weaken so that the water behind it destroys the structure, suddenly releasing tons of water.

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Forces of Nature: ThinkQuest 2000 (Team #C003603)

http://library.thinkquest.org/C003603/english/flooding/earthendamsandlevees.shtml [ f l o o d i n g   :   e a r t h e n   d a m s   a n d   l e v e e s ]

People living in valleys or on flood plains next to earthen dams or levees are susceptible to sudden flooding. Earthen dams are usually built across rivers to dam them up. Levees, on the other hand, are made alongside rivers to keep them from spilling over. However, both can fail in the event of an earthquake, internal erosion, poor engineering and construction, or avalanches. The most common cause of failure, however, is too much rainfall.

When a region experiences heavy rainfall, the water behind a dam or levee builds up and flows over the top. This will wash away the upper portion of the barrier and carves out deep grooves. The dam or levee will eventually weaken so that the water behind it destroys the structure, suddenly releasing tons of water.

[ back to graphics version ]

Forces of Nature: ThinkQuest 2000 (Team #C003603)

http://library.thinkquest.org/C003603/english/flooding/earthendamsandlevees.shtml