Dam

A dam “is a structure built across a river or stream to hold back water." Dams have a vast history ranging from the current day back to some of the earliest known societies. Throughout history, the materials used to construct and support these structures have evolved greatly. To compare between the two different times, “ancient dam builders used natural materials such as rocks or clay. Modern-day dam builders often use concrete." Man made dams, when constructed, naturally create a reservoir adjacent to the structure. These reservoirs serve as water storage for many industries in its area. They also serve secondary purposes such as providing a waterbody for “fishing, boating, and other leisure activities” [1].

Within dams, structures may be built to create mechanical power and electricity, or hydroelectric power. Many of these hydroelectric dams were created in the early 1900’s, in an era of “big dam” building in America as demands for electricity increased. During the Great Depression, President Franklin D. Roosevelt put Americans back to work through "massive dam building projects." Dams since then have evolved and are able to provide water, and electricity to a vast area [1].

Dams have been viewed as one of the biggest engineering accomplishments. There are so many benefits, but as of recently, “ecologists who study rivers and lakes have uncovered some environmental downsides to dam construction. Dams change the way rivers function, and in some cases, this can harm local fish populations." Dams also can affect biodiversity when widespread flooding has to take place to fill the reservoir [1].

References

[1] National Geographic Society.(2019, July 29). Dams. Retrieved (2021 July 17), from www.nationalgeographic.org/encyclopedia/dams/.