The mighty Mississippi River, stretching across the United States from Minnesota to Louisiana, has captivated adventurers and writers since the earliest days of exploration. Despite its iconic status, the Mississippi River has always been mystifying in its own right, and the bright brown, muddy muck it carries in its current has been one of the signature features of the river, to the point where most people’s image of the Mississippi is the swirling brown waters bordered by green banks. But what exactly causes the river’s muddy color?
According to the United States Geological Survey, the muddy color of the Mississippi River is caused by a combination of suspended sediment and naturally occurring soil from the river’s drainage basin. When the rain or snow melts, the soil is washed into smaller streams and rivers, and eventually into the Mississippi. In addition, runoff from roads, farms and cities can contribute to the muddy color. The combination of all these different suspended soils, or sediment, creates the muddy hue of the Mississippi River.
The amount of suspended sediment depends on the river’s flow rate. When the Mississippi is low, the sediment is more tightly suspended and the river is much muddier. When the flow rate is higher, the sediment is able to spread out and the muddy hue is less apparent. In addition, the amount of sediment also depends on the geography of the river’s basin. The more fertile an area is, the more sediment is produced, and thus the muddier the river. As the muddy sediment enters and flows down the Mississippi, it is spread further downstream and deposited in areas along the river’s edge, creating the iconic muddy banks.
The turbidity of the Mississippi is measured in Nephelometric Turbidity Units (NTU). The average range for the river is from 20-50 NTU, depending on the flow rate and season. If the NTU is higher, meaning there is more sediment, the color of the water also becomes darker. However, there are certain geographical areas of the Mississippi, such as the delta region, where the turbidity is much higher due to the addition of more sediment.
The amount of sediment in the Mississippi River has both positive and negative impacts. On the positive side, sediment is a natural form of fertilizer that can help improve the soil quality in areas along the river’s edge. In addition, the sediment content of the river also serves as a natural form of water filtration, filtering out pollutants and toxins before they enter the water system. The downside, however, is that sediment can cause the river to become more shallow, leading to the risk of flooding and other river hazards.
Muddy sediment in the Mississippi River is a naturally occurring phenomenon, but the amount of sediment and its impacts can also be affected by human activities such as farming, logging and construction. For example, logging can cause more runoff from the land and enter into the river, thus increasing the sediment content of the river. It is important to consider these human activities when assessing the impacts of muddy sediment in the Mississippi River.
Erosion
Erosion further contributes to the Mississippi River’s muddiness. Rivers, as they move through their watersheds, eat away at the land they pass through. As they do, they take away land, soil, rocks, and other material. Depending on the erosion rate, this can cause a significant increase in the Mississippi’s turbidity. This is especially the case for areas through which the river quickly traverses, such as the middle Mississippi.
Sediment Management
Sediment management is an important tool for maintaining the health of the Mississippi River. Sediment management can help reduce the amount of sediment entering the river, and reduce the turbidity of the water. This can be done through various methods, such as buffer strips and sediment traps, structures to trap sediment before it enters the river. Sediment management can also help reduce the risk of flooding and other problems with increased sedimentation.
Floods
Floods can have a major impact on the turbidity of the Mississippi River. During floods, a much higher amount of sediment is washed into the river, increasing its turbidity. This can lead to additional flooding, as the higher sediment can cause the river to become shallower and less able to flow, leading to back up and flooding.
Oil Pollution
Oil pollution is another factor that can contribute to the Mississippi River’s muddiness. Due to its industrial use, oil can often find its way into the river, causing sediment and other materials to be mixed in the water. This can cause the water to become more turbid, further adding to the iconic muddy color of the Mississippi.
