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The 5 Things that Drove Expansion in the 1800s
July 9, 2020

A River Runs Through Us



The United States is blessed with an assortment of beautiful, mighty rivers.

They have served as functional forms of transportation as well as provided us with drinking water, recreational opportunities and hydroelectric power.

Each is important in its own way and each has its set of challenges.

Here’s a look at five of our longest rivers.

The Missouri River

Given the prominence of the Mississippi River, you might think it’s the longest river in the United States. It isn’t.

That honor goes to the Missouri River.

The Missouri travels 2,341 miles from its starting point west of Bozeman, Montana, to where it converges with the Mississippi just north of St. Louis.

The river’s route is a winding one that cuts through Montana, North Dakota and South Dakota before forming the borders of Iowa and Nebraska, Nebraska and Missouri, and Missouri and Kansas before cutting across Missouri to join with the Mighty Mississippi.

It’s described as the “Center of Life” for the Great Plains.

The Missouri began as a home for Native American tribes who fished and hunted along its shores.

It was also a major mode of transportation during the westward expansion of the 1800s. Meriwether Lewis and William Clark explored the entire length of the river starting in 1804, looking for the Northwest Passage to the Pacific Ocean.

In the 1900s, the Missouri was utilized for irrigation and hydroelectric power.

Over the decades, channelization for better navigation has shortened the river by about 200 miles. In addition, industrialization and development have harmed some of the ecosystem along the river.

A scenic view of Lake Pepin on the Mississippi River in early autumn.

The Mississippi River

The Mississippi River isn’t that much shorter than the Missouri.

It meanders for 2,202 miles from its origin at Lake Itasca in Minnesota until it dumps into the Gulf of Mexico just southeast of New Orleans.

Along the way it forms part or all of the borders between seven pairs of states. It touches a total of 10 states altogether.

Among other attributes, the Mighty Mississippi helped power the steamboat era of the early 1800s.

Today, it provides drinking water for millions of people and helps support a $12 billion shipping industry. In fact, half of the nation’s corn and soybean crops are barged along the upper stretches of “Old Man River.”

The river is prone to flooding, as happened in May 2019 in Illinois, Iowa and other Midwest states. In April 2023, significant flooding was reported and predicted along the northern Mississippi between Minneapolis and Davenport, Iowa, as the river reached some of its highest levels in 20 years.

Dams and levees have been built along 2,000 miles of Mississippi watershed to help control the overflows.

In recent decades, the Mississippi has suffered from environmental and pollution problems due to industrial facilities along its banks. In fact, agricultural pesticide runoff has formed a “dead zone” near the river’s delta at the Gulf of Mexico.

In 2012, the Mississippi River Cities and Town Initiative was formed to deal with flooding problems and to preserve the watershed’s natural ecosystem. Now, 85 mayors are on board.

Taos, New Mexico, at Rio Grande Gorge Bridge over the Rio Grande at dusk.

The Rio Grande

The Rio Grande is the third longest river in the continental United States (fourth overall if you include the Yukon River in Alaska).

The Rio Grande is mostly associated with Texas, but the historic river actually starts in the Rocky Mountains of southern Colorado.

It cuts through the heart of New Mexico, including Albuquerque, before joining Texas at El Paso and forming the entire border between the Lone Star State and Mexico.

Its total length is 1,759 miles. Its deepest depth is 60 feet.

The river was a major source of contention between the United States and Mexico in the first half of the 19th century. It was one of the factors that started the Mexican American War in 1846.

The United States signed treaties in 1906 and 1944 with Mexico over water usage.

Texas, New Mexico and Colorado also signed the Rio Grande Compact in 1939 to regulate water use.

The Rio Grande’s water is in high demand.

About 95 percent of the river’s annual water flow is diverted for municipal and agricultural uses. The river irrigates more than 2 million acres of cropland in the United States and Mexico.

At some points, the river is wild and scenic. At other locations, especially down river in Texas, it runs nearly dry.

Climate change is affecting this grand river. Geologists say the watershed could have 30 percent less water flow as snow packs shrink and evaporation rates rise. All this while water demand increases in places such as Albuquerque and El Paso.

Reflection of Grand Canyon in Colorado River.

The Colorado River

The Colorado River has an unusual feature that few other major rivers have.

It doesn’t eventually converge with another river or dump into an ocean or gulf.

After flowing 1,450 miles from its beginnings in the Rocky Mountains of Colorado, the river simply runs dry in Mexico a few miles short of the Gulf of California.

The Colorado is the nation’s fifth-longest river and also one of its most valuable.

It winds through seven states. They include Utah and Nevada, the two driest states in the country. The Colorado also traverses through three desert regions. It’s the river that formed the Grand Canyon and still slices through the middle of that national treasure.

Perhaps not surprising, the demands for Colorado water exceed what the river basin can deliver. The original water usage agreement for the river allowed allotments of 17.5 million acre-feet a year. Since then, the river’s annual average flow has shrunk to 12.5 million acre-feet per year.

The river supplies drinking water to 36 million people, including residents of Los Angeles, Las Vegas, Phoenix, Tucson and San Diego.

It also helps irrigate 4 million acres of farmland and provides 12 billion kilowatt-hours of hydroelectric power per year.

Utah had been seeking more water from the river’s Lake Powell. Arizona and California are constantly in need of more water.

In addition, climate change is expected to reduce the Rocky Mountain snowpack and shrink the amount of water flow into the Colorado, just as it’s predicted to do to the Rio Grande.

To help ease the crunch, seven states reached an agreement in March 2019 to better manage the Colorado River’s water in the face of climate change and droughts. However, in May 2023, the states had to renegotiate water use rights because several dry years had brought the river’s levels to historic lows. Under the new agreement, California, Nevada and Arizona reduced their water allotments by another 13 percent. This pact is in place until 2026.

All this led the organization American Rivers to declare in its annual report in April 2023 that the Colorado was the most endangered river in the country.

Environmental groups say action needs to be taken now. They’ve come up with five water conservation goals they say could salvage 4.4 million acre-feet of Colorado River water every year.

A colorful sunset sky is reflected on the Ohio River as photographed from the shore at Paden City, West Virginia looking across to the Ohio side of the river.

The Ohio River

The Ohio River is only the 10th longest river in the United States, but it is one of the hardest working.

It travels 979 miles from its starting point in Pittsburgh where the Alleghany and Monongahela rivers meet to its endpoint where it flows into the Mississippi River at Cairo, Illinois. The Ohio, in fact, is the Mississippi’s largest tributary by volume.

Native American tribes lived along the Ohio for thousands of years. The Seneca tribe gave the body of water its name by calling it “Ohiyo,” which means “beautiful river.”

In the late 1700s, the river was the southern boundary of the Northwest Territory. It also served as an extension of the Mason-Dixon Line, separating free states from slave states. At narrow passages of the Ohio, such as near the city of Cincinnati, slaves crossed the river to enter free states. Those that were caught were “sold down the river” back to slave states. That’s where that term comes from.

In the 1800s, the Ohio also served as an economic engine. In David McCullough’s book, “The Pioneers,” he discusses how important the river was to settlement in the Ohio Valley as well as commerce throughout the Midwest.

Today, the Ohio is still used by barges to transport oil, coal, steel and other goods. The river carries an estimated 230 million tons of cargo per year. It also has 20 dams and 49 power generating stations.

A price, however, has been paid for this workload.

In 2018, the state of Ohio sued DuPont, saying the company for decades discharged a chemical called PFOA that’s used to make Teflon into the Ohio River. The lawsuit is still pending.

The Ohio River Foundation reports that during rainstorms raw sewage is dumped into the river at 1,350 different locations. Not good for a river that supplies drinking water to 3 million people.

The group also reports that acid mine drainage is affecting water quality in the upper regions of the river.

It notes that many sections of the Ohio do not meet water quality standards for bacteria, pathogens, lead, mercury and other pollutants.

Reports like these led an environmental group in 2009 to declare the Ohio the most polluted river in the United States. In 2015, the federal Environmental Protection Agency made the same assessment. The 2023 American Rivers report named the Ohio as the second most endangered river in the nation.

However, groups such as the Environmental Law and Policy Center report progress on cleaning up the Ohio River, although they note there is a lot more to do. Similar work is being done by the Kentucky Waterways Alliance.