Hydropower and Marine Energy Industry Workers

Water power has been used for thousands of years. The ancient Chinese, Greeks, and Romans used water-powered mills to perform everyday tasks such as grinding wheat and sawing wood. Later cultures used water to power manufacturing plants and textile mills.

According to the National Hydropower Association (NHA), the precursor to the modern hydro turbine was developed in the mid-1700s. In 1849, an engineer named James Francis developed the Francis Turbine. This type of turbine is the most widely used today.

In 1882, the first hydropower plant began operating in Appleton, Wisconsin, on the Fox River. By 1886, there were approximately 45 water-powered electric plants in the eastern United States and Canada. In 1887, the first hydroelectric plant opened in the western United States, in San Bernardino, California.

In the early 20th century, the federal government began to take a more active role in the management and use of waterways and the generation of power using water. It established the Bureau of Reclamation in 1902. The bureau was created to help build and manage dams, power plants, and canals to encourage economic development in the western United States. (Today, it is the second largest producer of hydroelectric power in the western United States.) In 1920, the Federal Water Power Act was enacted. It encouraged the development of hydroelectric projects, such as dams and reservoirs. In 1931, construction began on the Hoover Dam (one of the most famous dams in the world). At its peak, more than 20,000 workers were involved in the project. The dam began generating power in 1937, and is still in operation today. In 1933, the Tennessee Valley Authority was established. Its main goal was to construct dams to generate, sell, and distribute electrical power in order to improve the economic climate in the Tennessee River Valley. In 1940, hydropower provided 40 percent of electrical generation in the United States.

Today, despite calls by environmentalists to dismantle dams in order to protect endangered and threatened species, and for other reasons, the hydropower industry continues to be a key player in renewable energy. Hydropower is the largest and least expensive type of renewable energy in the United States. In 2018, hydropower constituted 7 percent of the utility-scale electricity generated in the U.S. and 39 percent of utility-scale electricity generated from all renewable energy, according to the Energy Information Administration. 

In addition to hydropower generated by rivers, streams, and lakes, researchers are studying the use of other water resources—such as tidal energy, ocean thermal energy conversion, and wave energy—to generate power.