Montana's Missouri River: Pollution's Impact

The Missouri River, the longest river in the United States, has been affected by pollution and human activity in several ways. With its origin in Montana, the river flows through several states and has faced various environmental challenges, including water pollution and the impact of dams and levees on its natural flow and surrounding ecosystems. The construction of dams, such as the Fort Peck Dam, has altered the river's flow and affected the habitats of various animal species, including birds and fish. Additionally, agricultural pollution, particularly from fertilizers, has led to increased algae growth and contributed to the Gulf Hypoxia in the Gulf of Mexico. The river's water quality has improved over the years, but residues of banned pesticides can still be found in fish, and wastewater discharges pose health risks for swimmers.

The impact of climate change and poor flood management

The Missouri River, flowing from southern Montana to St. Louis, Missouri, has been described as the "center of life" for the Great Plains. However, the river has faced significant threats due to climate change and poor flood management practices.

Climate Change Impacts

Montana's Missouri River is highly susceptible to the impacts of climate change. A 2012 Bureau of Reclamation report predicted a 10% increase in runoff in the Lower Missouri River due to changing climatic conditions. As a result, the river and its surrounding communities are at increased risk of devastating floods, which pose threats to public safety, wildlife, and industries across the Great Plains states.

Poor Flood Management

In addition to climate change, poor flood management practices have exacerbated the challenges faced by the Missouri River. The river is highly controlled by artificial channels, levees, and dams that attempt to mitigate flood damages. However, these structures have inadvertently contributed to the problem. The river, once up to 10,000 feet wide, has been narrowed to pinch points of just 1,200 feet, leaving rising water with nowhere to go. Consequently, major floods regularly breach the levee system, causing significant damage and repair costs exceeding $1 billion.

Impact on Wildlife

The Missouri River's native fish and wildlife have suffered due to development activities such as dam construction and levee building. The loss of good habitat and changes in water clarity have led to a decline in fish species, with an estimated loss of more than 80% of the fish in the river. Additionally, bird species such as the endangered least tern and the threatened piping plover require flood activity to scour clean their habitats of vegetation. When water levels are raised to support recreational and industrial uses, these bird species lose their habitat and become more vulnerable to predators.

Impact on Agriculture and Water Quality

The Missouri River basin has also witnessed significant land-use changes. Between 1892 and 1982, cultivated land in the floodplain areas between Sioux City, Iowa, and St. Louis increased by 4300%, while tree cover, wetlands, sandbars, and grasslands declined significantly. These changes have impacted water quality, with higher bacterial counts and increased levels of pesticides and fertilizers entering the river. As a result, the Missouri Department of Natural Resources does not recommend swimming in the river due to health risks, and there are advisories in place regarding the consumption of certain fish species.

Need for Nature-Based Solutions

To address the issues of climate change and poor flood management, nature-based solutions have been proposed. This includes implementing levee setbacks, restoring floodplains, and giving the river more room to flood safely. By embracing these solutions, it is hoped that the impacts of flooding can be mitigated while also restoring the river's ecosystem and protecting vulnerable communities.

Pollution from pesticides and herbicides

The Missouri River, which flows from southern Montana to St. Louis, Missouri, is America's longest waterway. The river has been affected by pollution from human activities, including the use of pesticides and herbicides.

Pesticides and herbicides are synthetic compounds used to control unwanted organisms, such as weeds, insects, and other pests. They are often applied to croplands and pasture lands to increase crop yields and can find their way into water bodies like the Missouri River through various means, including storm runoff, discharge from reservoirs, and atmospheric deposition.

The Missouri River, being part of the Mississippi River basin, is affected by the extensive use of pesticides and herbicides in the region. The Mississippi River basin contains the largest and most intensively farmed region in the United States, with about two-thirds of all pesticides used for agriculture in the country applied in this area. The intense use of these chemicals raises concerns about potential adverse effects on water quality and the health of aquatic life, as well as the millions of people who rely on the river for drinking water.

Herbicides, a type of pesticide, are the most heavily used category, with atrazine, alachlor, and metolachlor being the most commonly applied compounds in the production of corn and soybeans. These herbicides have been detected in high concentrations in the Mississippi River and its tributaries, including the Missouri River. Their presence in the water can have detrimental effects on the health of aquatic organisms and the overall ecosystem.

To address the issue of pesticide pollution, the University of Montana's Flathead Lake Biological Station has received a $6.6 million grant from the Environmental Protection Agency's Columbia River Basin Restoration Program. The program, led by Dr. Rachel Malison, aims to reduce pollution, improve water quality, and educate the public about the impacts of pesticides on Montana's waters. The program will focus on the Upper Columbia River Basin, which includes Montana's Clark Fork, Kootenai, and Flathead rivers.

Water quality and sewage issues

In the 1960s, the river's pollution reached a crisis point, with a large section of the river below Kansas City suffering a massive fish kill due to a loss of dissolved oxygen caused by the amount of sewage and other organic solids in the water. This event highlighted the urgent need to address the river's sewage problems.

In 1972, the passage of the Federal Clean Water Act set strict new rules for water quality and provided funding for the construction of wastewater treatment plants. Since then, significant improvements have been made, with garbage dumping eliminated and all wastewater now required to be treated before discharge. However, residues of banned pesticides such as DDT, dieldrin, and chlordane are still found in Missouri River fish, and the Missouri Department of Health has advised against consuming certain fish species due to the presence of these contaminants.

While the water quality of the Missouri River has improved, there are still concerns about the impact of agricultural pollution, especially from fertilizers. High levels of nitrates and phosphorus from fertilizers are entering the river and contributing to the formation of a hypoxic zone in the Gulf of Mexico, which kills fish and harms ecosystems. Additionally, there are issues with septic tanks in Montana, which are a significant source of pollution.

Overall, while efforts have been made to improve water quality and sewage issues on the Missouri River, there are still ongoing challenges related to agricultural pollution, septic systems, and the presence of contaminants in fish populations.

The effect on native fish and wildlife

The Missouri River has been affected by a variety of human activities, including dam construction, levee building, floodplain development, and agricultural pollution. These factors have had a significant impact on the native fish and wildlife that depend on the river for their habitat and food sources.

One of the main issues is the loss of good habitat, which has resulted in an estimated loss of more than 80% of the fish in the river. The construction of dams and levees has altered the natural flow of the river, changing the habitats that many fish species rely on. The river is now channelized for navigation over 650 miles and impounded by dams over 903 miles. Most of the remaining free-flowing portions of the river are near the headwaters in Montana. The loss of habitat has particularly affected species such as the pallid sturgeon and the flathead chub, which are in serious decline.

In addition to habitat loss, pollution from agricultural runoff and sewage has also impacted the river's fish and wildlife. High levels of nitrates and phosphorus from fertilizers are entering the river, contributing to the Gulf Hypoxia in the Gulf of Mexico. While most pesticide residues in the river are not considered harmful, the Missouri Department of Health has advised against consuming sturgeon due to the presence of chlordane and PCBs.

The changing water levels and increased water clarity due to the trapping of sediments in the main stem reservoirs have also had an impact on fish and wildlife. While some species have increased in numbers, such as skipjack herring and gizzard shad, others have declined or become more susceptible to predators. The endangered least tern bird and the threatened piping plover bird, for example, require islands and sandbars that are scoured clean of vegetation through flood activity. When water levels are raised to support recreation and industry, these birds lose their habitat.

The Missouri River's native fish and wildlife have also been affected by the serial discontinuity concept, where the water above a dam becomes inherently different from the water below. As sediment settles and the water warms up in the reservoirs, the fish at the top evolve and can no longer live in the colder, clearer water below the dam. This further disrupts the natural cycles and habitats of the native species.

Overall, the various human activities and pollution affecting the Missouri River have had significant impacts on the native fish and wildlife. Efforts are being made to restore the river ecosystem, but it will never be returned to its wild, untamed form. The future of many species depends on finding a balance between human needs and the needs of the river and its inhabitants.

The role of the US Army Corps of Engineers

The US Army Corps of Engineers has played a significant role in addressing the issues affecting the Missouri River in Montana. The Corps has been at the forefront of efforts to mitigate the impacts of pollution and human development on the river ecosystem.

One of the key initiatives led by the Corps is the Missouri River Recovery Program, a collaborative effort with the U.S. Fish and Wildlife Service. This program aims to restore the natural form and function of the Missouri River ecosystem, which has been impacted by the construction of dams and levees. These developments have disrupted the habitat of native fish and wildlife, and the program seeks to revitalise the ecosystem for the benefit of all basin inhabitants. The Corps has also been involved in flood management along the Missouri River, which is one of the most controlled waterways in the nation. Artificial channels, levees, and dams have been constructed to manage flood damages, but this has resulted in narrow pinch points that constrict the flow of rising water and lead to frequent breaches of the levee system.

In recognition of the complex challenges facing the Missouri River, the US Army Corps of Engineers has developed the Missouri River Recovery Management Plan and Environmental Impact Statement. This plan was created in collaboration with the Kansas City and Omaha Districts of the Corps and the U.S. Fish and Wildlife Service. It provides a comprehensive assessment of the actions necessary to comply with the Endangered Species Act and protect three federally listed threatened and endangered species associated with the river: the pallid sturgeon, the interior least tern, and the Northern Great Plains piping plover. The plan utilises the best available science to develop alternatives and evaluate their effects on environmental resources and human uses of the river. It also includes an adaptive management plan to ensure continuous improvement in decision-making based on regular monitoring and assessment.

The US Army Corps of Engineers has also been called upon by organisations like American Rivers to prioritise projects that reduce flood risk and restore fish and wildlife habitats along the Missouri River. This includes identifying repetitively damaged levees and planning projects that give the river room to flood safely, reducing the risk of severe disasters caused by climate change and poor river management. The Corps' involvement in these projects demonstrates its commitment to finding solutions that balance flood control with ecological resilience and the needs of affected communities.

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