The Mississippi River, which carries a rich history of Native Americans, explorers, early settlers, and the infamous blues, has a color that varies between several shades. The hue of the water is determined by several factors, including the type of soil in the watershed and the nutrients from wastewater from industrial and agricultural activities downstream. It is often described as a dark or slate gray, or a rusty orange or red.
Depending on the angle of the sun’s rays and the area of observation, the Mississippi River can appear different in color. The angle of the sun’s rays and the camera lens used can create various hues in photographs. For example, images taken directly in the sun’s rays or from a steeper angle close to the surface can create a sparkling blue-green river. Photos taken from a lower angle can show the muddy depths, displaying a brown color.
In general, the color of the Mississippi River is a result of its sediment load. The magnolia state discharges its soil sediments into the water causing it to become more murky and opaque. As the water moves downstream to the Gulf of Mexico, it collects sediment from the other tributary rivers along the way. The resulting turbid water takes on a grayish color.
In addition to the color of the river, the clarity of the water can range significantly. Before entering the sea the water surface may become discolored due to the effect of waves and wind, but it will still be transparent. During rainstorms and floods though, the turbidity of the river significantly increases, making it nearly opaque. This can also happen when wastewater containing silt, oils and fertilizer runoff is introduced to the water body.
Although the Mississippi River is often dark and murky in color, it can at times appear in brighter hues. From April to June during the spring season, there is often a light greenish tint due to the seasonal runoff of grass and other vegetation.
The murky, dark color of the Mississippi River is typical and is considered normal due to the sediment load that it carries. Although it may look unappealing and muddy from a distance, it is actually full of life. In addition to the aquatic species, the river supports a variety of bottom-dwelling organisms, birds, and mammals.
Experts have noted other factors that influence the color of the Mississippi River. A natural effect of mineral deposits on banks and shorelines, as well as the presence of algae in the water body can also contribute to its color. But mostly, the natural sediment content accounts for the majority of the coloration.
Water Quality
The color of the Mississippi River is not only determined by its sediment load, but also by the presence of pollutants. Industrial and wastewater treatment facilities, oil and gasoline spills, stormwater runoff from cities, and agricultural waste from farms can all seep into the river, changing the hue of its waters. Pollution can also impact the clarity of the water and the health of the wildlife.
The U.S. Geological Survey (USGS) monitors the water quality of the Mississippi River by testing more than 115 parameters including biochemistry, organic chemicals, metals, and sediments on a regular basis. Their data provide insights into the extent of contamination in the river and can be used to track the progress of septic systems, wastewater treatment, and other best management practices.
The Mississippi carries a large load of nitrogen and phosphorus, primarily from fertilizer runoff. These nutrients can significantly impact the aquatic life and local ecosystems. The USGS found that the water quality of the Mississippi River is generally good and has been improving overall, but there are still areas of concern.
Wildlife Impact
The varying hues in the water can also affect the aquatic wildlife. Fish, insects, and other creatures rely on the color of their environment to survive, as certain species require different kinds of light penetration and protection. Red light, for example, is better absorbed by some species of fish, while yellow and green light is more visible to them.
The color of the water is also known to be an indicator of the pH, temperature, and oxygen levels. Studies have found that water turbidity can limit the visibility of predators, leading to reduced predation pressure on the ecosystem, which allows smaller fish and aquatic insects to thrive without fear. It can also provide refuge to fry, eggs, and larval fish that may be overwhelmed in the presence of high turbidity.
The Mississippi River provides a vital source of water for many aquatic species. The turbid color and murky waters are essential to the survival of many animals and help to keep their population levels in balance.
Erosion and Sedimentation Impacts
The color of the Mississippi River is also related to the rate of erosion and sedimentation in the region. The sediment load in the river can be attributed to destabilization of the soil through activities such as deforestation, grazing, and agricultural practices. In the Upper Mississippi, sediment has been found to be around 25-50% higher than natural levels due to man-made activities in the watershed.
In addition, dredging activities, construction activities, and the installation of dams and locks can result in increased levels of sedimentation. This can change the color of the river and make it more turbid, leading to increased erosion of the banks and shorelines, as well as sedimentation of bottom habitats. These changes in the sediment load have consequences for the resident species and can be a source of environmental degradation.
The sedimentation of the river can also affect the flow of the water and the transport of materials and pollutants downstream. As the sediment builds up, it can clog the channels, resulting in reduced water flow and increased flooding. This can then result in habitat degradation, disruption of the fish and wildlife populations, bank erosion, and changes in the salinity.
Environmental Regulations
Various governmental agencies, including the Environmental Protection Agency, have imposed regulations to reduce the amount of pollution and sediment entering the Mississippi River. These efforts are designed to reduce the spread of contaminants, improve the water quality, and help maintain healthy aquatic habitats. In the past, only point sources such as industrial wastewater and municipal sewage were regulated, but recently the EPA has implemented more stringent regulations on non-point sources such as agriculture, urban runoff, and stormwater.
These regulations are paying off, although there are still significant issues to be addressed. The USGS studies have shown that the overall water quality in the Mississippi River is improving, with more areas displaying good water quality than poor water quality. This is a direct result of the improved water management, increased treatment, and improved best management practices.
The EPA also recommends that stakeholders and decision makers develop new policies to reduce the amount of sediments entering the river. This includes promoting conservation practices, improving the efficiency of agricultural practices, and controlling stormwater runoff.
Conclusion
The Mississippi River is an iconic symbol of the United States, with its muddy waters reflecting the history of the people along its banks. Though the color of this river changes depending on the angle of the sun’s rays, the type of soil in the watershed, and the pollutants from industry, it is generally a dark or slate gray. This murky hue is caused by the sediment load and other aquatic-connected factors.
The Mississippi River is an important source of life and water for many species, including fish, insects, and mammals. To ensure that this river stays healthy and balanced, proper environmental regulations and practices must be upheld to reduce the amount of pollution and sediment entering its waters. With proper protection today, the Mississippi will be able to keep its legacy alive for years to come.
