ABSTRACT
Engineered waterways may be divided into two basic categories: canals and slackwater navigation systems. Canals are artificial waterways used for inland navigation, often constructed parallel or in close proximity to rivers, and equipped with locks and, more rarely, inclined planes, to facilitate descents and ascents. Canals reached their heyday in the United States in the first half of the nineteenth century, beginning with New York State’s Erie Canal. A slackwater navigation system is a series of locks and dams constructed in an existing or widened river channel to permit protected navigation. This development, often termed canalization, transforms a free-flowing waterway to a series of slackwater pools. First extensively developed in the later nineteenth century in the United States, construction of slackwater navigation systems continues today. Among prominent slackwater systems are the Upper Mississippi, the Ohio, the Kanawha, the Tennessee, the Monongahela, and the Allegheny.
