The Longest Rivers in South Dakota

The James River in South Dakota.
The James River in South Dakota.

South Dakota is located in the Midwestern area of the United States. The state has an area of about 77,116 square miles, which makes it the nation’s seventeenth largest state. South Dakota is a spectacular state due to the availability of plenty of stunning features. These features include national parks and monuments, rivers, and other things. Examples of such rivers include the majestic Missouri River, the Little Missouri River, and Belle Fourche River.

Longest Rivers in South Dakota

The longest river is the Missouri River, which has a length of a massive 2,340 miles. James River is a distant second with a length of around 710 miles while the White River is third with 580 miles. The Little Missouri River is fourth with 560 miles while the Big Sioux River closes the top five with about 419 miles. The Moreau River is tenth with a flat 200 miles.

Missouri River

The Missouri River is the longest river system in all of North America with its course starting at the Rocky Mountains all the way to the Mississippi River. The river’s watershed is responsible for draining a region with an area of at least half a million square miles. This drainage area includes ten US states and two Canadian provinces. In South Dakota, it forms part of the border between South Dakota and Nebraska. After the border stretch, it joins up with the James River and forms part of the border between Iowa and Nebraska. Some of its tributaries include the Jefferson River and the Madison River.

James River

Also called the Dakota River or the Jim River, this river drains a region with an area of about 20,653 square miles in both North and South Dakota. The river begins flowing from an unnamed location in Wells County, North Dakota and drains into the Missouri River in Yankton County, South Dakota. From North Dakota, it flows into South Dakota through Brown County where it is utilized for the formation of two reservoirs. Sometimes, due to a drop in the gradient of the channel, this river experiences reverse flow, especially when its tributaries have a high inflow.

White River

This river, which flows through the states of South Dakota and Nebraska, is actually a tributary of the Missouri River. The water of this river appears to be white, which is where the name came from. The river’s source is at Pine Ridge in Nebraska and drains into the Missouri River at Lyman County in South Dakota. The White River has a drainage basin of about 10,200 square miles, of which 8,500 square miles of the basin is in South Dakota. Because of the harsh climate in the badlands, some parts of this river do not have flowing water all around the year. However, the section close to Chamberlain has water flowing throughout the year.

Tributaries of the Rivers

The Little White River, the eighth longest in the state, should not be confused with the White River above since the former is a tributary of the latter. Previously, the Little White River was called the South Fork of the White River. The flow starts at the Pine Ridge Indian Reservation and drains into the White River some 12 miles from Murdo.

The Longest Rivers in South Dakota

1Missouri River 2340 miles (3770 km)
2James River 710 miles (1140 km)
3White River 580 miles (930 km)
4Little Missouri River560 miles (900 km)
5Big Sioux River419 miles (674 km)
6Cheyenne River 295 miles (475 km)
7Belle Fourche River290 miles (470 km)
8Little White River 234 miles (377 km)
9Moreau River 200 miles (320 km)

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