The Ohio River, historically expressed in the Iroquoian language as ohiːyoːh meaning “the great river,” is the largest tributary by volume in the Mississippi River Basin. Its over 490,600 square-mile drainage basin extends throughout 14 states, from New York to northern Alabama. The watershed is an immense, diverse, multi-use system comprised of multiple beaches and islands, hundreds of major and minor tributaries, and thousands of acres of backwaters, wetlands, nature preserves, and forested lands. Numerous boat ramps, marinas, condominiums, expansive estates, stilted riverfront homes, barge mooring stations and several quarries line the river. The river provides drinking water to local communities and is threatened by profuse point source discharges from massive industrial facilities and publicly owned treatment works, combined sewer overflows, agricultural pollution and 12 coal fired power plants.