The Tennessee Valley Authority (TVA) official Web site contains an abundance of information. Born out of the Great Depression in 1933, the TVA strives to "support sustainable economic development, supply affordable, reliable power, and manage a thriving river system." The site contains information about the history of the governmental agency, as well as current and future objectives. Of special interest is the River Systems link, which tells of the extensive work and research that has taken place on the streams that the TVA manages.