The Big Eddy is a stretch of rapids in Chouteau County, Montana, in the Northwestern Glaciated Plains region. It lies about 9.5 miles northeast of Malmstrom Air Force Base and roughly 14 miles northeast of Great Falls as the crow flies.
The Northwestern Glaciated Plains are rolling grassland and cropland shaped by ice-age glaciers, with prairie potholes and few waterfalls.
There are 5 recorded rapids in Chouteau County.
The Big Eddy is located at 47.6078° N, 111.0468° W. The listing is based on the USGS Geographic Names Information System, one of the sources compiled by the U.S. Geological Survey in its inventory of waterfalls and rapids of the conterminous United States. The position was verified on aerial imagery. Details on trails, parking and access have not been documented for this rapid yet.