The Missouri is the longest river in the world's largest navigable river system, the Mississippi River Basin (Kane 26). Measuring about 3,000 miles from its source in southwestern Montana, up through North Dakota and then down to meet the Mississippi in St. Louis, it is also the longest river in North America (Lass A History 1-4). In 1856, at the time of the Arabia Steamboat mishap, it had been traveled by Native Americans for centuries, if not millennia. Lewis and Clark followed it on their way to the Pacific Ocean.
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| The Missouri river and its major tributaries (Lass Navigating 16) |
There are two different geological sections of the Missouri. The shortest, less than 200 miles, is a section in Montana from Fort Benton to Cow Island which cuts through solid rock. Much of this area is preserved by the Upper Missouri Breaks National Monument.
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| Upper Missouri River Breaks National Monument map - blm.gov |
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| Upper Missouri River Breaks National Monument - blm.gov |
From there to Saint Louis the river flows through easily erodible sand and mud. Fed by northern High Plains rain and melting snow, the river is shallow and meandering. Before the navigation and flood control projects, the soft banks would crumble heaving whole trees into the river (Lass A History 1-4). Over time the fallen trees became dangerous. These snags ominously lay submerged, waiting for the steamboats (Lass Navigating 21).
Upper and Lower Missouri River
The delineation between the Upper and the Lower Missouri was imprecise, depended upon the source and changed over time. In general, the river between St. Louis and Council Bluffs and/or Sioux City was the lower Missouri, beyond that was the Upper River.
These maps show the sections of the river:
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| Upper Missouri River Ports (Lass Navigating 182) |
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| Lower Missouri River Ports (Lass Navigating 88) |
Navigation
Western river steam-boating began in 1811 with the Robert Fulton designed New Orleans. By 1817 the first steamboat had reached St. Louis, the Mississippi Valley commerce hub (Lass Navigating 38-39).
A federally sponsored expedition, based more on lucrative government contracts than on sound technology, sent the first steamboats to the Upper Missouri River in 1819. The four steamboats in the company were ill-suited for the shallow, muddy, fast-moving Missouri, as were the inexperienced navigators. Attempts to reach the Upper Missouri trading posts were abandoned for a while (Lass Navigating 44-45).
Attention turned to navigating the lower Missouri as fur business expanded and Euro-Americans settled in the Missouri Valley. By 1829 there was regular steamboat service along the Missouri River from St. Louis to Independence, MO. This less expensive water transportation was used for government troops, their dependents, Indian removal, slave shipping and supplies for the emerging settlements (Lass Navigating 70-73, Buchanan 12).
Efforts to navigate the Upper Missouri continued with success coming with the design of low draft boats able to navigate the shallow river. Finally, in 1860, the farthest point, Fort Benton, was reached. Named for our expansionist politician, Thomas Hart Benton, reaching Fort Benton reaching meant the entire three thousand miles of the Missouri River was navigable (Lass A History 13-19).
Although there was a straight shot (relatively speaking) up the Mississippi River from New Orleans to St. Louis and traffic from the Ohio River could reach St. Louis, the Mississippi Valley was separated from the east coast trading centers. That changed with the opening of the Erie Canal in 1825 and the locks built to bypass the Falls of the Ohio in 1830 (Nash IV: 73, Lass Navigating 72-73). Now there was a water route from the east coast, primarily the commercial center New York, to the Rocky Mountains.
More canals came on board, as seen in the following 1840 map, continuing to improve water transportation.
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| Encyclopedia of American History - p. 73 |
One last map shows the overland trails taking off from supply centers along the Missouri River. Travel went as far as possible by boat and then took off on the trails.
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| Lass - Navigating - p. 244 |
