This basin was known for soil erosion, deforestation and destructive floods. From the beginning, the TVA achieved outstanding success. 50 dams were constructed which controlled the intermittent flooding, provided electricity and created lakes for recreational purposes. Today, the TVA employs about 19,000 persons and distributes power over about 80,000 square miles to a population of more than 7 million. More than 60 million people visit the recreational facilities each year.
Levees are embankments along the course of a river.
Dikes are similar in all respects except they usually refer to holding back large standing bodies of water, such as an ocean. For example, a system of dikes hold the North Atlantic Ocean from flooding the Netherlands. Many rivers produce levees naturally during floods when the overflowing river deposits silt and debris along the bank. Gradually this builds up and contains the stream into the channel. Artificial levees are constructed in much the same manner.