Mackinaw River

Mackinaw River
Mackinaw River near Tremont, Illinois
Physical characteristics
Source 
  locationFord County east of Sibley, Illinois
  coordinates40°35′20″N 88°21′59″W / 40.5889233°N 88.3664421°W / 40.5889233; -88.3664421 (Mackinaw River origin)
Mouth 
  location
Confluence with the Illinois River near Mapleton, Illinois
  coordinates
40°33′06″N 89°43′56″W / 40.5517055°N 89.7323284°W / 40.5517055; -89.7323284 (Mackinaw River mouth)
  elevation
443 ft (135 m)
Length130 mi (210 km)
Discharge 
  locationGreen Valley, Illinois
  average772 cu/ft. per sec.
Basin features
ProgressionMackinaw River → Illinois → Mississippi → Gulf of Mexico
GNIS ID403283

The Mackinaw River is a 130-mile-long (210 km) tributary of the Illinois River in the U.S. state of Illinois. Its watershed covers approximately 1,136 square miles (3,000 km2), and contains some of the most productive agricultural land in the United States. The river itself maintains some of the highest quality streams in the state and provides habitat for 60-70 native fish species and 25-30 species of mussels. Its name, also spelled Mackinac, is derived from the Ojibwe word mikinaak meaning "turtle".