River Facts

Rivers of the United States:

  • The United States has more than 250,000 rivers. That’s 3.5 million miles of rivers.
  • The largest river is the Mississippi, which has a flow volume of 593,000 cubic feet per second at its mouth.
  • The longest river is the Missouri, which flows for approximately 2,500 miles.

Rivers are threatened:

  • More than 235,000 river miles in the United States have been channelized.
  • More than 600,000 river miles are impounded behind dams.
  • More than 25,000 river miles have been dredged for navigation.
  • More than 50% of wetlands have been lost or destroyed nationwide in the past century.
  • Nearly 40% of the rivers and streams in the U.S. are too polluted for fishing and swimming.
  • Thirty percent of the native freshwater fish species in North America are threatened, endangered, or of special concern.
    Why protect rivers? Click here for some reasons.

Longest rivers in the United States:

  • Missouri: 2,540 miles 
  • Mississippi: 2,340 miles
  • Yukon: 1,980 miles
  • Rio Grande: 1,900 miles
  • St. Lawrence: 1,900 miles
  • Arkansas: 1,460 miles
  • Colorado: 1,450 miles
  • Atchafalaya: 1,420 miles
  • Ohio: 1,310 miles
  • Red: 1,290 miles
  • Brazos: 1,280 miles
  • Columbia: 1,240 miles
  • Snake: 1,040 miles

(Source: Statistical Abstract of the U.S., 1986)

Dam facts

  • On average, we have built one dam a day every day since the signing of the Declaration of Independence. (Interior Secretary Bruce Babbitt)
  • Currently, 600,000 miles of our rivers lie behind an estimated 60,000 to 80,000 dams. (source: National Park Service)
  • The 600,000 miles of rivers lying behind dams amounts to fully 17% of our nation’s river mileage. (source: National Park Service)

River fish & wildlife facts:

  • Fully 80% of all vertebrate wildlife in the Southwest depend on riparian areas for at least half of their life.
  • Of the 1200 species listed as threatened or endangered, 50% depend on rivers and streams.
  • At least 123 freshwater species became extinct during the 20th century. These include 79 invertebrates, 40 fishes, and 4 amphibians. (There may well have been other species that were never identified.)
  • Freshwater animals are disappearing five times faster than land animals.
  • In the Pacific Northwest, over 100 stocks and subspecies of salmon and trout have gone extinct and another 200 are at risk due to a host of factors, dams and the loss of riparian habitat being prime factors.

(source: National Park Service)

Habitat facts:

  • Only 7% of the country’s landscape is in a riparian zone—only 2% of which still supports riparian vegetation.
  • The U.S. Fish and Wildlife Service estimates that 70% of the riparian habitat nationwide has been lost or altered.
  • Over 90% of the nearly 900,000 acres of riparian areas on Bureau of Land Management land are in degraded condition due to livestock grazing.
  • Riparian areas in the West provide habitat for more species of birds than all other western vegetation combined—80% of neotropical migrant species (mostly songbirds) depend on riparian areas for nesting or migration.

(source: National Park Service)

A river fact for your state:

Alabama Beneath its waters, the Cahaba River is home to 131 different species of fish—more species per mile than any river of its size in the country. It also provides habitat for fresh-water mussels and aquatic insects found nowhere else in the world.

Arkansas The Arkansas River forms in the Rocky Mountains in Colorado and meanders 1,450 miles through Kansas, Oklahoma, and Arkansas. It is the main water source for the state of Arkansas.

California Feisty fish and fierce rapids are the calling cards for the Upper Klamath, California’s second-longest river.

Colorado Dropping from the heart of the San Juan Mountains—Colorado’s largest subrange of the Rockies—the Animas River, at an elevation of 9,230 feet, is one of the highest boatable rivers in America.

Connecticut The Connecticut River, and its watershed ecosystem, is an immense and diverse region in New England encompassing over 11,260 square miles and 148 tributaries. The River is 410 miles long, traverses four states and is the source of 70% of Long Island Sound’s fresh water.

Florida The southern Withlacoochee, one of Florida’s finest touring rivers, is over 100 miles long with 84 miles of good canoeing trail.

Georgia As the East’s largest state, Georgia has 71,000 miles of rivers and streams.

Idaho The third largest river in the Rockies is the Clearwater of Idaho, flowing with 15,500 cfs (cubic feet per second) into the lower Snake River.

Illinois The state’s largest inland water system is Carlyle Lake, which covers 26,000 acres in Southern Illinois.

Iowa With the Missouri River to the west and the Mississippi to the east, Iowa is the only state bordered by two navigable rivers.

Indiana Flowing through the forests of the Southern Indiana Hill Country, the Blue River is the most spring fed of all Indiana’s streams. The many springs account for the aqua-blue color of the river, leading to the name "The Blue".

Kentucky The Green River is one of Kentucky’s largest, longest, and most navigable rivers. It flows west creating Green River Lake and draining twelve counties before emptying into the Ohio River across from Evansville, Indiana.

Louisiana All the rivers of Louisiana flow into the Gulf of Mexico or into other rivers that do so. The principal rivers that lie in or partly in Louisiana are the Mississippi, Red, Ouachita, Sabine, Pearl, Atchafalaya, and Calcasieu rivers.

Maine Maine: 32,000 miles of rivers and streams, 6000 lakes and ponds, and 3,500 miles of coastline.

Maryland There are 17,000 miles of rivers and streams (including 42 actual rivers) flowing into the 1,726 square miles of the Chesapeake Bay in Maryland.

Massachusetts The Charles River is 80 miles long, flows through 23 towns and cities, and 35 towns and cities comprise its watershed. The Charles River is swimmable much of the year, along much of its length.

Michigan Michigan is blessed with more than 1500 miles of quality canoeing streams, offering more paddling opportunities than any other state.

Minnesota The name of the Mississippi River comes from the The Ojibway Indians of northern Minnesota, who called it "Messipi" or "Big River," and it was also known as the "Mee-zee-see-bee" or the "Father of Waters."

Mississippi There are some 250 tributaries of the Mississippi, which drain a total area of more than 1,247,000 square miles--one third of the nation’s landmass!

Missouri Big Spring, that feeds into the Current River, is the largest single outlet spring in the US. Both the Current and the Jack’s Fork Rivers are part of the Ozark National Scenic Riverways, which was the first National Scenic Riverways in the country.

Montana Montana is known as a headwaters state because much of the water that flows to the rest of the nation comes from the mountains of Montana. Two of the nation’s major river systems-the Missouri and the Columbia-are born high in the Rocky Mountains of Montana.

New Hampshire New Hampshire has 1300 lakes or ponds and about 40 rivers with a total mileage of about 41,800 miles.

New Jersey The Delaware River region’s namesake is the river on which General George Washington made his famous Revolutionary Crossing on Christmas Day in 1776. You can see the crossing re-enacted each Christmas at Washington Crossing State Park in Titusville.

New Mexico Over 60% of the surface waters in New Mexico flow through San Juan County in the Animas and San Juan Rivers.

New York In and around the Adirondack Park you'll find some of the best canoeing and kayaking in the world. Coursing through pristine forests and dramatic mountains are more than 30,000 miles of brooks and streams, 6,000 miles of rivers and almost 3,000 lakes and ponds.

North Carolina The New River, located in the Appalachian mountains of Ashe County, is the oldest river in the nation and the second oldest in the world.

Ohio The Muskingum River is the largest river lying wholly within Ohio, and has the distinction of being the only river in the state to have been formally and expressly declared navigable, by an act of Congress in 1796.

Oregon Oregon leads the nation with the most designated Wild & Scenic Rivers at 48.

Pennsylvania In 1992, 85 miles of the middle Allegheny was designated a National Wild and Scenic River, based on its recreational value. All of the middle Allegheny is class I water, suitable for beginners.

Tennessee The Ocoee River in southeastern Tennessee is rated among the top white water recreational rivers in the nation and is the site for the Olympic white water canoe/kayak competition in the 1996 Olympics.

Texas The Rio Grande, the longest river in the State of Texas and forms the longest waterway segment of the State’s boundary.

Utah With average descents of 13 feet per mile the Green River tumbles past soaring red rock walls, desert Big Horn Sheep, pristine springs and waterfalls.

Vermont The White River used to be a main Native American route between lower New England and Montreal, but as a walking trail, not a canoe route.

Virginia The James River flows entirely in Virginia and is one of the longest rivers that remains entirley in one state. It is also the site of Jamestown, the first permanent English settlement in the Americas, founded in 1607.

Washington Early settlers gave the White Salmon River its name suggested by the pale bodies of spawning fish which at times nearly choked the mouth of the stream.

West Virginia Dropping 26 feet per mile through a gorge that averages 500 feet in depth, the Gauley River is famous for its outstanding whitewater and is one of the most technical rivers in the nation.

Wisconsin Southwestern Wisconsin’s Kickapoo River is particularly popular with canoeists. Often called "the most crooked river in the world" the smooth-flowing Kickapoo twists and turns for nearly 120 miles.

Wyoming As queen of northern Rockies rivers, the 700-mile Yellowstone begins in the Bridger-Teton Wilderness of Wyoming, flows through the raw wilds of grizzly bear country to Yellowstone Lake, then plunges over a 380-foot-high waterfall-the highest on any large-volume river in America.