The Grand River is the longest river in the U.S. state of Michigan. It runs 252 miles (406 km) through the cities of Jackson, Eaton Rapids, Lansing, Grand Ledge, Portland, Ionia, Lowell, Grand Rapids, and Grand Haven. Native Americans who lived along the river before the arrival of the French and British called the river O-wash-ta-nong, meaning Far-away-water, because of its length.
As the glacial ice receded from what is the central Lower Peninsula of Michigan around 11,000 years ago, the Maple River and lower Grand River served as a drainage channel for the meltwater. The channel ran east to west, emptying into proglacial Lake Chicago, the ancestor of Lake Michigan. Today the Grand River rises in Somerset Township in Hillsdale County and Liberty Township in Jackson County, and flows through Jackson, Ingham, Eaton, Clinton, Ionia, Kent, and Ottawa counties before emptying into Lake Michigan. Its watershed drains an area of 5,572 square miles (14,430 km2), including 18 counties and 158 townships. Tributaries of the river include (beginning near river source and travelling downstream): Portage River, Red Cedar River, Looking Glass River, Maple River, Bellamy Creek, Flat River, Thornapple River, Rogue River, Coldbrook Creek, Plaster Creek, Bass River, and Crockery Creek.
…Grand Rapids was built on the site of a mile long rapids on the Grand River, although these have disappeared after the installation of a run-of-river dam in 1866 and five low-rise dams during a river beautification project in 1927.