Big Bend of Missouri River

Big Bend of the Missouri River

Google Earth

This unique feature of the Missouri River in central South Dakota is amazing to see on land, but equally fascinating to view from above. It’s the Big Bend of the Missouri where the men of the Corps felt they gained little progress in late September 1804.

William Clark sent George Drouillard and John Shields across the “neck,” the narrowest strip of the odd-shaped peninsula, to hunt while the rest of the Corps continued to follow the river.

Clark wrote, “We Sent a man to step off the Distance across the gouge [neck]. He made it 2000 yds. The distance around is 30 miles. The hills extend thro the gouge and is about 200 foot above the water.” Based on this Google Earth image, the narrowest part of the neck is today approximately 1,285 yards (3,855 feet) wide – however, the gap will vary based on river level.

Humorist George Fitch wrote in 1907, “the Missouri River is the original loop-the-loop artist.” In most other river locations where a severe loop like this has occurred, the river changes course bypassing the loop, leaving what we know as an “oxbow” lake.

But the Big Bend has remained, primarily due to the geology of the area – there’s shale bedrock in the right places of the bend which impedes erosion. Plus, as Clark noted, the neck of the bend is high enough (180 to 200 feet) that is has never been topped by spring floodwaters. Finally, the Big Bend Dam (lower right corner) which created Lake Sharpe in 1964 has greatly reduced the springtime rampages of the river.

Image: Google Earth

Image Description: A three-dimensional aerial view of the Big Bend, as it makes a giant “S” in the South Dakota landscape. The river enters from the lower left-hand corner and exits view in the mid-center on the right side of the image. The fertile land in between the curves is dotted with large, irrigation crop circles which appears as different shades of green. The river’s color is dark green.