About the Mississippi River

Why It Is Important

The Mississippi River system supports more than 400 species of wildlife, including several endangered species, such as the pallid sturgeon, the alligator gar, the ancient paddlefish, and the Higgins Eye pearlymussel to name just a few. Wildlife refuges protect some of the most vital habitats. These refuges include the Upper Mississippi River National Wildlife and Fish Refuge, which is the longest river refuge in the continental United States. It alone hosts 119 species of fish.¹

The Mississippi River valley is one of Earth’s great migration corridors. Songbirds that winter in Central and South America and the Caribbean and over 40% of North America’s ducks, geese, swans and wading birds rely on the Mississippi River as a flyway, providing them direction, resting places, and food for epic seasonal migrations.²   In fact, the longest migration route in the Western Hemisphere lies in this flyway, beginning on the Arctic coast of Alaska in the north and ending in Patagonia in the south.³

Human Intervention

Over time, development, pollution and structural changes to the river for navigation and flood control have changed the river, destroying much of its ecological vitality — the very qualities that make it such an important part of our communities. Poor water quality and loss of habitat are limiting the River’s ability to support life. Plant and animal species are declining dramatically.

Sediments that were once naturally deposited in the Gulf of Mexico are now trapped behind locks and dams in the upper river, creating an excess sediment burden in the upper system while starving the delta of sediments that renew vital coastal wetlands – some of the most productive wildlife habitat in the world, and some of the most endangered.

What You Can Do

We can help protect the River’s habitat and many species by supporting habitat restoration programs on both public and private lands and getting involved in local projects to clean up the river and restore natural areas. At home, we can create habitat in our own yards by planting native plants and trees and avoiding the use of lawn and garden chemicals that can pollute the river and threaten wildlife health. For more information on what you can do, go to the River Action Items section.

¹ Mississippi River Water Quality and the Clean Water Act: Progress, Challenges, and Opportunities (2008) Water Science and Technology Board (WSTB), National Academies Press http://books.nap.edu/openbook.php?record_id=12051&page=21
² http://www.fmr.org/mississippi
³ http://earthday.wilderness.org/backyard/flyways/mississippiroutemap.htm

Why It Is Important

The great Mississippi River system runs through America’s heartland, culture and economy. From forest and mountain headwaters, across prairies, farm fields and savannas, through hundreds of small towns, and some of America’s greatest cities, the River connects lives and livelihoods. About 12 million people live in the 125 counties and parishes that border the Mississippi River. Over 70 million people live in its basin.¹

Its extensive habitat and open space, including  thousands of acres protected in refuge systems, are important for wildlife, but also for the region’s economy. As American Rivers states: "The Mississippi is a cultural and recreational treasure for the nation. Tourism, fishing and recreation generate about $21.4 billion each year, and contribute 351,000 jobs along the river."²

More than half of America’s farms are part of the Mississippi River basin.³  The Mississippi River basin produces almost all (92%) of the nation's agricultural exports, over three quarters (78%) of the world's exports in feed grains and soybeans, and most of the livestock and hogs produced nationally. In addition, the Gulf's fish and shellfish industry is worth $26 billion annually (including Texas' oyster harvest).⁴ Almost all of these fish and shellfish rely on estuarine habitat provided by the Mississippi River during some stage of their life.⁵ 

The Mississippi River serves as an important commercial transportation corridor to ship hundreds of millions of tons of commodities each year, supporting a $12.6 billion shipping industry with 35,300 related jobs.⁶   Well over half (60%) of all grain exported from the United States is shipped via the Mississippi River through the Port of New Orleans and the Port of South Louisiana.⁷

What You Can Do

The River’s vivid character is woven into the history of its communities, the resilience of its peoples, and in our nation’s stories and songs. Riverboats, jazz, corn-dogs at state fairs, catfish, Mark Twain, bayous, and dozens of other images evoke the essence of the Mississippi. This River is deeply imprinted in the American imagination.  The one and only Mississippi is America's River; it is ours to respect, to care for and protect.  Do your part to defend our mighty River by becoming a River Citizen today.

¹ Mississippi River Water Quality and the Clean Water Act: Progress, Challenges, and Opportunities (2008) Water Science and Technology Board (WSTB), National Academies Press http://books.nap.edu/openbook.php?.
² http://act.americanrivers.org/site/DocServer/mississippi.pdf?docID=692
³ Compiled from data from the USDA Economic Research Service, "Major Land Uses in the United States, 2002"
⁴ Mississippi River Basin & Gulf of Mexico Hypoxia: Fact Sheet. EPA Web Site and Mississippi River Basin and Gulf of Mexico Factoids (April 10, 2003) - Fact sheet provided by Ron Nassar, Lower Mississippi River Conservation Committee http://www.epa.gov/msbasin/taskforce/factsheet.htm (Viewed November 8, 2007)
⁵  Mississippi River Conservation Committee and Restore Our Coast, Protect Our Cities. Environmental Defense. http://www.environmentaldefense.org/page.cfm?tagID=500  
⁶ http://act.americanrivers.org/site/DocServer/mississippi.pdf?docID=692
⁷ National Parks Service. Mississippi River Facts. Accessed on 22 June, 2009. http://www.nps.gov/miss/riverfacts.htm

Why It Is Important

More than 18 million people depend on the Mississippi River for drinking water.  Like many of the world’s largest rivers, the Mississippi starts as a clear-water stream in its headwaters, but picks up loads of sediment and becomes a murky, brown river as it flows downstream, earning the river one of its many nicknames: the Big Muddy. While some sedimentation is natural in a big watershed, the high levels in the Mississippi are largely the result of the vast amount of agriculture in the region. Rains and melting snows carry loose topsoil along with pesticides, fertilizers and manure, into the Mississippi River watershed.

Industrial wastes were routinely dumped into the river and its tributaries before modern pollution laws were enacted in the 1970s. But even after the passing of the Clean Water Act, enforcement has been problematic and stretches of the Mississippi River are heavily polluted by the wastewater from oil refineries, chemical production and other industries. 

Sewage is another large-scale threat to the Mississippi River’s water quality. According to the Clean Water Act, America’s waters are supposed to be "fishable and swimmable," but aging sewage systems, rapid growth of suburban development, and increased stormwater from a changing climate all contribute to the failed capture of pollutants before they reach the River. Many cities along the river have combined sewer systems, which treat both sanitary sewage and stormwater. Following heavy rains, these systems can be flooded, flushing untreated overflow into the River. This means raw sewage, bacteria and other pathogens flow directly into the River, along with debris, oil and grease from city streets, road salt and other pollutants.

Based on a recent national EPA study of streams and small rivers, Dr. Eugene Turner of Louisiana State University concluded that about half of the streams and rivers in the Mississippi River watershed are in poor condition, unsafe for swimming, drinking or recreational contact.¹

While communities that depend on the Mississippi River for drinking water treat and purify the water for human uses, nothing is done for the fish and wildlife that also depend on the River. The costs of cleaning up excessively polluted water are usually incurred by local communities and taxpayers.

 What You Can Do

To safeguard the River, and the people and wildlife that depend upon its waters, you can work for stronger enforcement of clean water laws, support projects to modernize sewage treatment systems, and encourage agricultural practices that reduce soil erosion and chemical use. At home, you can take simple steps like conserving water, which helps reduce the amount of water handled by overtaxed sewage systems, and avoiding lawn and garden chemicals, which can reduce chemical and nutrient loads in the river. For more information on what you can do, go to the River Action Items section.

¹ USEPA Wadeable Streams Assessment, A Collaborative Survey of the Nations Streams. December 2006. www.epa.gov/owow/streamsurvey

Why It Is Important

The Mississippi River basin is the third largest watershed in the world, after the Amazon and Congo basins, respectively. Through its vast tributary system, the basin reaches from the northern Rocky Mountains in the west to the Appalachian Mountains in the east. The system drains parts, or all, of 31 states and two Canadian provinces across a landscape of 1.2 million square miles, comprising 41% of the contiguous United States and 15% of the North American continent. The Mississippi River flows into its delta and the Gulf of Mexico at the average rate of 811,530 cubic feet per second— the third largest river basin in the world.¹

The Mississippi River watershed is comprised of six distinct basins: the Upper Mississippi, Ohio River, Missouri River, Tennessee River, Arkansas Red and White Rivers and the Lower Mississippi.

Human Intervention

Before human intervention, the Mississippi River flowed through the landscape in a changing mix of main channels and side channels, splitting and rejoining around hundreds of islands, periodically flooding its surrounding lowlands or floodplains. This pattern produced a wide range of habitats within and around the river, from swampy backwaters to oxygen-rich rapids and from island chains to fertile plains enriched with the sediments deposited from floods.

Humans used the Mississippi River corridor for transportation and trade for thousands of years without changing its natural flow. But as the American frontier expanded westward, the River’s natural hazards to navigation were met with engineering prowess, creating channels which were safer for large vessels to transport both passengers and commodities. To achieve this greater flow of people and products, the Army Corps of Engineers constructed a series of 26 locks and dams between Minneapolis and St. Louis, fundamentally changing the River's natural flow and habitat.

While the River has been modified to allow for increased traffic, a separate engineering effort has existed to control the River's floods. Over the years, levees have been constructed in various communities from Commerce, MO, to New Orleans, limiting floods in these communities in most years, but also changing the River’s natural flow and distribution of sediments, converting important riverside habitats and floodplains into man-made embankments. Nutrients that previously enriched floodplain soils and sediments that built coastal wetlands are now blocked and channeled into the Gulf of Mexico instead.

Today's Mississippi is a highly-engineered system. All the structural changes have contributed to rapid loss of coastal wetlands and other natural habitat. They have also degraded water quality in the River and the Gulf and have shifted, and sometimes intensified, patterns of flooding and erosion.

What You Can Do

You can help restore and protect the River's natural state by volunteering with one of the many Mississippi River Network member organizations throughout the region. Please check out our map to find the one nearest you.

¹ National Research Council. (2008). Mississippi River Water Quality and the Clean Water Act.  The National Academies Press: Washington, DC.

What It Is

It’s a dreadful name for a dreadful phenomenon caused by the pollution the Mississippi River carries into the Gulf of Mexico. The dead zone describes the area of the Gulf at the mouth of the Mississippi River whose waters can no longer support marine life because it is starved of oxygen. While the size of the dead zone changes seasonally, the floods of 2008 produced one of the largest dead zones yet. It covered more than 8,000 square miles—an area roughly comparable to the size of New Jersey or twice the surface area of all the inland lakes in Minnesota.

The River releases tens of thousands of pounds of fertilizer and animal manure, which are loaded with the nutrients nitrogen and phosphorus, into the Gulf. These nutrients "over-fertilize" the water, creating massive algal blooms that use up much of the dissolved oxygen in the water off the Louisiana and Texas coast.

Why It Is Important

No oxygen (or insufficient oxygen) means no life. The oxygen-depleted waters force fish and wildlife to migrate out of dead zones, while bottom–dwellers like Gulf shrimp often cannot escape the dead zones and die. Scientists call this oxygen-depleted condition hypoxia, and it is getting worse in the Gulf.

Reducing the amount of pollution, especially nitrates, that is carried into the Gulf via the Mississippi River is essential to restore healthy conditions in the Gulf and the river system. Agricultural pollution from the extensive Corn Belt is damaging the entire watershed. We can clean up and protect the River and shrink the dead zone by reducing chemical inputs on farms, shifting to more sustainable farming practices and improving "green infrastructure" to capture and filter runoff in wetlands, forested flood plains and other natural systems. Restoring natural floodplains, meanders and other features that slow the volume and intensity of floods will also help capture sediments and nutrients, reducing the tons that reach the Gulf.

What You Can Do

At home, River Citizens can help by conserving water, eliminating "cosmetic" uses of lawn and garden fertilizers, properly disposing of pet waste and supporting farmers who maximize their use of soil and nutrient conservation practices. For more information on what you can do, go to the  River Action Items section. To learn more about hypoxia and the Gulf of Mexico:

• Visit the Gulf of Mexico Dead Zone site, developed by the Science Museum of Minnesota, or
• Watch the HowStuffWorks video on hypoxia in the Gulf of Mexico.