Dam Ecosystems

The beaver is admired by some for its ability to create a small pond and new ecosystem, which enhances the water table, while also adding to the plant and animal diversity of the area. Man-made dams and natural waterfalls also affect the local environment, but they do so in a different manner.

Waterfall

• Natural waterfalls often migrate over a long period of time. The classic example is Niagara Falls, which has moved several miles since it first formed during the most recent glaciation. This is due to pressure applied by the falling water to the base of the falls. As a result rocks and debris from the foot of the falls is carried downstream. After a while, the falls move a few feet.

Man-made Dams

• Man-made dams, especially a large series of them, significantly change many aspects of the river ecosystem. Sediment buildup increases behind the dam, fish migration on the river ceases (unless special projects are included), the course of the water flow changes and adjacent forests are dramatically altered.

Beaver Dams

• Beavers naturally build dams that help the water table of the area. By using natural materials such as sticks and mud to build his dam, the beaver constructs a dam where water flows over top without any erosion at the base. The new body of water also offers protection from predators while creating a pond ecosystem.