The Mississippi River is reported to have different lengths depending on the source consulted. The EPA says it is 2,320 miles long, the United States Geologic Survey says it is 2,300 miles long and the staff of Itasca State Park at the Mississippi's headwaters say it is 2,552 miles long.
The reported length of any river can change depending on the measurement method or the year. This happens because length may increase when erosion or deposition occurs at its delta or when meanders are cutoff or created. The Mississippi River's width is narrowest at Lake Itasca where it is only 20 to 30 feet wide. It is widest at Lake Winnibigoshish where it is more than 11 miles.