The Boyer River is a tributary

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of the Missouri River

Missouri River

The Missouri River flows through the central United States, and is a tributary of the Mississippi River. It is the longest river in North America and drains the third largest area, though only the thirteenth largest by discharge. The Missouri's watershed encompasses most of the American Great...

, 118 miles (189.9 km) long, in western Iowa

Iowa

Iowa is a state located in the Midwestern United States, an area often referred to as the "American Heartland". It derives its name from the Ioway people, one of the many American Indian tribes that occupied the state at the time of European exploration. Iowa was a part of the French colony of New...

 in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. Most reaches of the river's course have been straightened and channelized.

The Boyer River is named for a settler who hunted and trapped in the watershed

Drainage basin

A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...

 before the time of Lewis and Clark

Lewis and Clark Expedition

The Lewis and Clark Expedition, or ″Corps of Discovery Expedition" was the first transcontinental expedition to the Pacific Coast by the United States. Commissioned by President Thomas Jefferson and led by two Virginia-born veterans of Indian wars in the Ohio Valley, Meriwether Lewis and William...

. Explorers, including Lewis and Clark, John James Audubon

John James Audubon

John James Audubon was a French-American ornithologist, naturalist, and painter. He was notable for his expansive studies to document all types of American birds and for his detailed illustrations that depicted the birds in their natural habitats...

, and Prince Maximilian zu Wied-Neuwied, navigated through the region near the mouth of the Boyer as they traveled up the Missouri River

Missouri River

The Missouri River flows through the central United States, and is a tributary of the Mississippi River. It is the longest river in North America and drains the third largest area, though only the thirteenth largest by discharge. The Missouri's watershed encompasses most of the American Great...

. This area is now part of the Boyer Chute

Boyer Chute National Wildlife Refuge

Boyer Chute National Wildlife Refuge, created in 1996, is located along the banks of the Missouri River in the U.S. state of Nebraska. The 3,350-acre refuge preserves an area that had been cultivated and neglected before the early 1990s...

 National Wildlife Refuge

National Wildlife Refuge

National Wildlife Refuge is a designation for certain protected areas of the United States managed by the United States Fish and Wildlife Service. The National Wildlife Refuge System is the world's premiere system of public lands and waters set aside to conserve America's fish, wildlife and plants...

 (NWR). This was originally an island

Island

An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, cays or keys. An island in a river or lake may be called an eyot , or holm...

 of sand and sediment

Sediment

Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....

 deposited in the Missouri River by the Boyer River. Gradually, the Missouri River eroded a major channel (chute) through the sediment; this came to be known as Boyer Chute, and was the preferred channel used by explorers and traders until the Missouri eventually changed its course.

Course

The Boyer River rises near Storm Lake

Storm Lake, Iowa

Storm Lake is a city in Buena Vista County, Iowa, United States. The population was 10,600 in the 2010 census, an increase from 10,076 in the 2000 census. It is the county seat of Buena Vista County. Storm Lake is home to Buena Vista University, originally Buena Vista College...

 in southwestern Buena Vista County

Buena Vista County, Iowa

-2010 census:The 2010 census recorded a population of 20,260 in the county, with a population density of . There were 8,237 housing units, of which 7,522 were occupied.-2000 census:...

 and initially flows southwardly into Sac County

Sac County, Iowa

-2010 census:The 2010 census recorded a population of 10,350 in the county, with a population density of . There were 5,429 housing units, of which 4,482 were occupied.-2000 census:...

. In southern Sac County it turns southwestward and flows through Crawford

Crawford County, Iowa

-2010 census:The 2010 census recorded a population of 17,096 in the county, with a population density of . There were 6,943 housing units, of which 6,413 were occupied.-2000 census:...

, Harrison

Harrison County, Iowa

-2010 census:The 2010 census recorded a population of 14,928 in the county, with a population density of . There were 6,731 housing units, of which 5,987 were occupied.-2000 census:...

 and Pottawattamie

Pottawattamie County, Iowa

Pottawattamie County is a county located in the U.S. state of Iowa. The population was 93,158 in the 2010 census, an increase from 87,704 in the 2000 census and is the second largest county by area in Iowa. The Pottawattamie county seat is located at Council Bluffs. It is one of three Iowa...

 Counties, past the towns of Deloit

Deloit, Iowa

Deloit is a city in Crawford County, Iowa, United States, along the Boyer River. The population was 288 at the 2000 census.-Geography:Deloit is located at ....

, Denison

Denison, Iowa

Denison is a city in Crawford County, Iowa, United States, along the Boyer River. The population was 7,339 at the 2000 census. It is the county seat of Crawford County.-Geography:Denison is located at ....

, Arion

Arion, Iowa

Arion is a city in Crawford County, Iowa, United States, along the Boyer River. The population was 136 at the 2000 census.-Geography:Arion is located at ....

, Dow City

Dow City, Iowa

Dow City is a city in Crawford County, Iowa, United States, along the Boyer River. The population was 503 at the 2000 census. The name is that of one of its founders.- History :The community was founded in 1869 by Simon E...

, Dunlap

Dunlap, Iowa

Dunlap is a city in Harrison County, Iowa, United States, along the Boyer River. The population was 1,139 at the 2000 census.-Geography:Dunlap is located at ....

, Woodbine

Woodbine, Iowa

Woodbine is a city in Harrison County, Iowa, United States, along the Boyer River. The population was 1,564 at the 2000 census.-Geography:Woodbine is located at ....

, Logan

Logan, Iowa

Logan is a city in Harrison County, Iowa, United States, along the Boyer River. The population was 1,545 at the 2000 census. It is the county seat of Harrison County. Henry Reel founded Logan in 1867, naming it in honor of General John A. Logan, a favorite army officer.-Geography:Logan's longitude...

 and Missouri Valley

Missouri Valley

Missouri Valley may refer to some places in the United States:* Missouri Valley, Iowa, a small city* The Missouri River Valley* The Missouri Valley Conference, a college athletic conference...

. It enters the Missouri River in northwestern Pottawattamie County, 13 miles (20.9 km) north of Council Bluffs

Council Bluffs, Iowa

Council Bluffs, known until 1852 as Kanesville, Iowathe historic starting point of the Mormon Trail and eventual northernmost anchor town of the other emigrant trailsis a city in and the county seat of Pottawattamie County, Iowa, United States and is on the east bank of the Missouri River across...

.

At Denison, the Boyer collects the East Boyer River, which rises in northwestern Carroll County

Carroll County, Iowa

-2010 census:The 2010 census recorded a population of 20,816 in the county, with a population density of . There were 9,376 housing units, of which 8,683 were occupied.-2000 census:...

 and flows southwestwardly past Vail

Vail, Iowa

Vail is a city in Crawford County, Iowa, United States. The population was 452 at the 2000 census.-Geography:Vail is located at .According to the United States Census Bureau, the city has a total area of , all of it land....

. In southwestern Harrison County, it collects the Willow River.