Hawaii's sugar industry enjoyed great success for most of the 20th century, and its influence was felt across a broad spectrum: economics, politics, the environment, and society. This success was made possible, in part, through the liberal use of Hawaii's natural resources. Chief among these was water, which was needed in enormous quantities to grow and process sugarcane. Between 1856 and 1920, sugar planters built miles of ditches, diverting water from almost every watershed in Hawaii.

Ditch is a humble term for these great waterways. By 1920, ditches, tunnels, and flumes were...