Brown-water navy

The term brown-water navy or riverine navy refers in its broadest sense to any naval force capable of military operations in littoral zone waters. The term originated in the United States Navy during the American Civil War, when it referred to Union forces patrolling the muddy Mississippi River, and has since been used to describe the small gunboats and patrol boats commonly used in rivers, along with the larger "mother ships" that supported them. These mother ships include converted World War II-era Landing Crafts and Tank Landing Ships, among other vessels.

U.S. Navy's "brown-water navy" river gunboat, firing napalm, during the Vietnam War.

Brown-water navies are contrasted with seaworthy blue-water navies, which can independently conduct operations in open ocean. Green-water navies, which can operate in brackish estuaries and littoral coasts, are the bridge between brown-water navies and blue-water navies.