I.

Introduction

Mississippi (river) (Algonquian Misi sipi,”big water”), river in the central United States, the largest and most important river in North America. The Mississippi has played a central role in the exploration and economic development of the continent, and it is a principal artery for bulk freight, carrying more than any other inland waterway in North America.

The Mississippi River system, comprising the Mississippi River and its tributaries, drains 2,979,000 sq km (1,150,000 sq mi). It is the largest drainage system in area in North America and the third largest in the world. Its discharge, which averages 16,800 cu m per second (593,000 cu ft per second), is the sixth largest in the world. The Mississippi River, from Lake Itasca in Minnesota to the Gulf of Mexico, is 3,770 km (2,340 mi) long. However, if the river system is measured from the headwaters of the Missouri River, the Mississippi's longest tributary, to the Gulf of Mexico, its length totals 5,970 km (3,710 mi).