Environmental Engineering Reference
In-Depth Information
What Is
Water Power?
A river rushes over rocks and its
waters fall hundreds of feet. At the
seashore, the ocean's waters come up
high on the shore. Hours later, the
tide
falls
back again. Farther out in the ocean, wind whips
the water's surface. Great waves rise and fall.
Moving water in rivers or the seas can create a beautiful
picture. Many people enjoy watching these natural sights.
Moving water can be more than beautiful, however. It can also
be a great source of power. Thousands of years ago, humans
i rst learned that moving water could turn wheels that were
made of wood. The turning wheels could then be connected
to large round stones. As the wheels moved, so did the stones.
The stones were used to grind corn or wheat into l our. Over
time, people found other ways to use water power. The energy
created by water has made life easier for many people around
the world.
Forms of Water Power
Water power comes in different forms. The most common type,
called
hydropower
, uses the energy created by moving water.
(
Hydro
comes from a Greek word meaning “water.”) Often,
dams are built across large rivers. Water l ows from a high point
on one side of the dam to a lower point on the other side. The
water has what is called
kinetic
, or moving, energy. The falling
