Mississippi River Basin

The world's fourth-largest drainage basin and encompasses more than 40 percent of the contiguous United States

The Mississippi River flows 3,778 kilometers from Lake Itasca in northern Minnesota to its delta in southern Louisiana. Its river basin starts in southern Ohio and ends on the coasts of Louisiana, draining 4.76 million square kilometers. The river includes tributaries from thirty-two U.S. states and two Canadian provinces. The Mississippi River drainage basin is the fourth largest in the world covering over 3,220,000 square kilometers. The basin lies in the southern U.S. in a humid climate, leading to higher rates of annual precipitation and seasonal variations that affect its major floods and river changes.

The Mississippi River in New Orleans, LA (2017)


ArcGIS Maps


River Regime Chart

2015 Monthly Mean Discharge in cubic feet per second


System Components

Tributaries flowing within Mississippi River Basin (2012)

Inputs: The Mississippi River collects water from snowpack, precipitation, stormwater, and seasonal variations such as hurricanes and tropical storms. During its meandering 2,350 mile journey south to the Gulf of Mexico, it is joined by hundreds of tributaries, including the Ohio and Missouri Rivers. Water from parts or all of 31 states drains into the Mississippi River, and creates a drainage basin over 1,245,000 square miles in size. The average annual precipitation rate that the Mississippi collects from Minnesota to Louisiana is 68 inches.

Outputs: The Mississippi River flows south ending in the Mississippi Delta in the coastal region of Mississippi and the South Louisiana Delta near New Orleans, LA. Both of these deltas feed into the Gulf of Mexico. The Mississippi Delta is located on the edge of the continental shelf of the Gulf of Mexico. Its bird's foot configuration is characteristic of alluvial deposition in deep water. In this configuration large volumes of sediment are required to create land area; consequently, land is being lost in this delta more rapidly than it is being created. The river is continuing to flood more water into the delta than it consume leaving sediment deposits as well to be at an all time high. The river has a discharge of 593,000 ft³/s.

Uses: For over two hundred years communities up and down the river have used the water to obtain freshwater and to discharge their industrial and municipal waste. A January 2010 study published by the Upper Mississippi River Conservation Committee states that close to 18 million people rely on the Mississippi River or its tributaries in just the upper half of the basin (from Cairo, IL to Minneapolis, MN). The Environmental Protection Agency says that more than 55 cities rely on the Mississippi for daily water supply. Agriculture is one of the primary users of the Mississippi River as well. It has altered the hydrologic cycle and energy budget of the entire region. The agricultural products and the huge agribusiness industry that has developed in the basin produces 92% of the nation's agricultural exports, 78% of the world's exports in feed grains and soybeans, and most of the livestock and hogs produced nationally. Almost all of these goods are shipped on the Mississippi River through the Port of New Orleans and the Port of South Louisiana.

Storage: Much of the water from the Mississippi River is stored within its main channel but also flows to surrounding lakes, rivers, and reservoirs. Many of the locks and dams along the river have connected reservoirs where excess water is held in times of flooding and severe storms. Most of the water stays within the main channel rather than flowing out to other tributaries. However, most of the water that is used for agriculture purposes gets held in man-made lakes and low altitude fields.


Flooding

Crevasse in levee on Mississippi River taken in 1913. Courtesy U. S. Corps of Engineers, Mississippi Valley Division

History: Flooding in the Mississippi was first recorded in 1543 when explorer Hernando Desoto encountered a flood on the river near Memphis, TN, that extended over 40 days and likely extended to the lower reaches of the river. The next account was not chronicled until 1734 when the city of New Orleans was inundated for several months. The National Weather Service (NWS) and National Oceanic and Atmospheric Administration (NOAA) holds forty three flood accounts of the Mississippi river from 1735 to 2019.

Recent Events: (Dec 28, 2018 through Aug 10, 2019) The longest known flood on record of the lower Mississippi River began in 2018. It utilized The Bonnet Carre Spillway for the 13th time in its history, and the first time in consecutive years. At peak flow of 213,000 cubic feet per second, a total of 206 gates out of 350 were opened. Baton Rouge went above flood stage of 35.0 feet the morning of Jan 6, 2019. On May 10th, and in the first time ever in its history, the Bonnet Carre Spillway was opened a second time due do excessive rainfall upriver. For the first time in the spillway's existence, it was in operation during the tropical cyclone season, as Hurricane Barry made landfall near Atchafalaya Bay. When Barry approached the Louisiana coast, it produced a surge up the river that saw a rise of 1 foot at New Orleans, briefly rose to 16.93 feet, then settling back to around 16 feet. Finally, on July 27th, the last bays of the Bonnet Carre Spillway was closed, ending a 79 day stretch of deployment. On August 4th, Baton Rouge finally fell below flood stage, a record 211 days in flood at Baton Rouge. Following six days after, the Red River Landing finally fell below flood stage. This created the longest flood on record at 226 days.

The City of New Orleans and the Mississippi River 1885 (Library of Congress)

Flood Mitigation: Flood control began in the Civil War when individuals from the Lower Mississippi River Valley began building agricultural levees. This led to organized levee districts which helped control the water's flow and manage any excess water. By 1914, fifty-two levee and drainage districts had been established between Rock Island, Illinois and Cape Girardeau, Missouri, laying the foundation for flood control far into the future. After this, Congress passed the country's first flood control act which authorized the Corps of Engineers to work on levees from Illinois to Louisiana.

Eventually, in the 1920s, environmentalists began to warn that river management for navigation and agriculture was threatening river ecology. In 1924, Congress established the Upper Mississippi River Wildlife and Fish Refuge, which grew to include 195,000 acres. Since then, dozens of procedures have take effect to conserve refuges and flood plains around the river basins.

Lock and Dam No. 15 in the Upper Mississippi River

By 1928, the U.S. had passed The Flood Control Act of 1928 (the largest public works appropriation ever authorized). This act set many of the processes in motion that created the current river management system. This system now includes 29 locks and dams that are crucial to the U.S. economy. The issue, however, is the system is now falling apart as agricultural rates, barge loads, and shipping companies have consistently increased their numbers year by year stressing the mitigation control of the river. The largest lock and dam on the river is Lock and Dam 15 spanning from Rock Island, Illinois, to Davenport, Iowa. It is the largest roller dam in the world. Its dam is 1,203 feet long and consists of nine 109 feet non-submersible, non-overflow roller gates and two 109 feet non-submersible overflow roller gates. The reservoir it creates (pool 15) holds over 100,000 cubic acres of water.

Graphical Hydrologic Outlook for the Mississippi River past Lock and Dam No. 15. The model displays the weekly chance of exceeding river stages on the Mississippi river.

Current Risk of Flooding: The Mississippi River is still rising from its annual staring level and will continue to rise through for the next one to two weeks as runoff from snowmelt upstream in combination with rainfall runoff is moving through the Upper Mississippi river system (assumption collected from NWS). With this, much of the river will most likely see minor to moderate flooding until the start of November. The river is expected to crest in the Dubuque, IA, area early next week, and continue down river.


Human Impact:

Ways Human Utilize the River:

A typical farming area in the Lower Mississippi River

  1. Agriculture: The Mississippi River provides ample supply of water for agriculture and is the heart of the world’s agricultural production. Nearly four out of 10 ears of corn grown in the world come from the Mississippi River watershed. Agriculture has been the dominant land use for nearly 200 years in the Mississippi basin, and has altered the hydrologic cycle and energy budget of the region. The agricultural products and the huge agribusiness industry that has developed in the basin produce 92% of the nation's agricultural exports, 78% of the world's exports in feed grains and soybeans, and most of the livestock and hogs produced nationally.Along the Mississippi river, Decatur, Illinois is the “Soybean Capital of the World”; Sumner County, Kansas is the “Wheat Capital of the World”; and Iowa is the “Food capital of the world”.
  2. Transportation: Before the development of railroads, river transportation played an important role in a country’s development. The Mississippi River, as the fourth longest river in the world and the longest in North America, was heavily used by humans as a medium for transportation. Many industries engaged in bulk shipping take advantage of the low-cost transportation of goods available on the river. The largest single bulk items moved on the river are petroleum products—gasoline, kerosene, fuel oil and lubricating oil. They are shipped upstream from the oil fields of Texas and Louisiana. Coal is shipped upstream from Illinois and western Kentucky. Sixty percent of all grain exported from the US is shipped on the Mississippi River through the Port of New Orleans and the Port of South Louisiana. In measure of tonnage, the largest port district in the world is located along the Mississippi River delta in Louisiana. The Port of South Louisiana is one of the largest volume ports in the United States. 
  3. Hydraulic power: The Mississippi river has 903 dams, making it the river in the world owning the most amount of dams. And there will be even more dams coming up in the future under the project “lock and dam”, which proposes to build dams in the upper Mississippi river and aims to generate twice as much as the electricity the river currently generates. The Mississippi River alone generates more than half of the hydroelectric power in the US.
  4. Recreational use: Local people have been fishing, swimming, and Kayaking in the Mississippi River. As the river becomes more and more polluted, those recreational activities are discouraged. The river also serves as a tourist spot as it provides cruises for visitors.

The Lock and Dam project on the Upper Mississippi River

River Contamination and River Engineering

A severe eutrophication on the Lower Mississippi River

River Contamination: Agricultural Runoff is one of the leading causes of water pollution in the United States. Current agricultural practices lead to excessive nutrient runoff from land and turn into eutrophication. The Mississippi River, producing ninety-two percent of the country's crop export, suffers from eutrophication the most. In addition, animal waste from livestock operation and farmland soil erosion contribute to the worrisome water quality of the Mississippi River. Lastly, deforestation in the Mississippi River, especially in the Alluvial Valley, which has lost eighty percent of its 22 million acres of forests in the last decade, has partially contributed to soil erosion. With all the pollution coming from humans, people also swim, fish, and even drink the water from the Mississippi River. Although the pH level of the river has decreased a little since its peak at 8.5 in the 1990s, the pH level still remains at 8, which had already made the water quality like sea water. The water temperature of the river also increased in the last two decades. In Missouri-Louisiana part of the Lower Mississippi River, for example, the temperature increase from 23.4 degree Celsius to almost 25 degrees Celsius in the last twenty years.

Soil Erosion in the Mississippi River

Ecological Health: The ecological health of the Mississippi River drainage basin has been altered as soon as humans started exploiting the river in the last 150 years. First, human-induced climate change has been creating more abnormal storms and drought in the region. Second, the depletion of wetlands in both the upper and the lower Mississippi River drainage basins severely damage the habitats of hundreds of native species. Wetlands are the most complex and diverse ecosystems. These factors Once they are damaged, it is nearly impossible to restore them. In conclusion, the current ecological health of the Mississippi River is not in good shape and the situation is degrading. However, with the increasing attention to the pollution and ecology in the Mississippi River, people start to attempt different methods to slow down or even reverse the current conditions.

Flooding of the Mississippi River

Soft Engineering: Numerous policies have been proposed to counter the worsening environment of the Mississippi River. Among them, "the Management of the Upper Mississippi River " is one of the more comprehensive management plans for the Mississippi River. In the plan, it thoroughly states the agreement with corporations regarding the issue of water pollution, the responsibility of local farmers, the cooperation within states, as well as the partnership with other non-profit organizations. Another example of this is a reforestation project launched by Disney and the Department of Agriculture. Funded by Disney, the project is aimed to plant 2,000 acres of trees. Although 2,000 acres is not a huge number, many small projects like this can still plant a substantially amount of trees and achieve the goal of restoring the already-lost forests.

A newly-built levee on the Mississippi River. The embankment has a gentle slope, which gives more space once floods take place.

Hard Engineering: The waterway of the Mississippi River has been shaped in many ways, big and small, to suit human needs such as irrigation, navigation, flood mitigation and etc. Since the 18th century, 3,500 miles of levees averaging 25 feet high have been constructed to contain the Mississippi River. The river channel is dredged nine feet deep so that ships can pass through. The channels' shapes are altered in order to decrease channel-bed elevation and disconnect the river channel from the flood plains. Besides these, engineers have also tried to change the flow of the river by installing weirs, which are dams designed to be topped by water so that the direction of the flow can change.


Works Cited & Annotated Bibliography:

The Mississippi River in New Orleans, LA (2017)

2015 Monthly Mean Discharge in cubic feet per second

Tributaries flowing within Mississippi River Basin (2012)

Crevasse in levee on Mississippi River taken in 1913. Courtesy U. S. Corps of Engineers, Mississippi Valley Division

The City of New Orleans and the Mississippi River 1885 (Library of Congress)

Lock and Dam No. 15 in the Upper Mississippi River

Graphical Hydrologic Outlook for the Mississippi River past Lock and Dam No. 15. The model displays the weekly chance of exceeding river stages on the Mississippi river.

A typical farming area in the Lower Mississippi River

The Lock and Dam project on the Upper Mississippi River

A severe eutrophication on the Lower Mississippi River

Soil Erosion in the Mississippi River

Flooding of the Mississippi River

A newly-built levee on the Mississippi River. The embankment has a gentle slope, which gives more space once floods take place.