Minnesota River Virtual Tour - Downstream


Stop 12 - Downstream: the Mississippi River


		Downstream Impacts Although our canoe journey down the Minnesota River ends when it meets the Mississippi River, the water flows on. If you kept heading downstream on the Mississippi River you would eventually end up in the Gulf of Mexico. The Mississippi River drains 40 percent of the US and flows downstream past cities such as St. Louis, Memphis, and New Orleans. Unfortunately, poor water quality in the Minnesota River contributes to problems downstream, particularly in Lake Pepin and the Gulf of Mexico's Dead Zone.
Lake Pepin Lake Pepin (photo at right) is a large natural compoundment of the Mississippi River 50 miles downstream from the Twin Cities. Lake Pepin is experiencing two major problems: increased sediment and increased phosphorus levels. The dominant source of sediment comes from the Minnesota River and due to this increase in sediment, the lake is filling in. In low-flow years, such as 1988 indicated in the photo, increased phosphorus can lead to excessive algae growth. Phosphorus discharged from the Minnesota into the Mississippi River has been identified as a significant source of Lake Pepin's problem.
Dead Zone When the Mississippi River flows into the Gulf of Mexico, it creates a massive area devoid of marine life called the Dead Zone. The nutrients carried by the Mississippi River promote large algal blooms each summer in the Gulf. Excess nitrogen, in particular, contributes to high rates of algae growth, and subsequent oxygen depletion when the algae die and decompose. The Minnesota River has been identified as one of several relatively high contributors of nitrogen into the Mississippi River. Thus, according to the Minnesota Pollution Control Agency, the Minnesota River may be at least partly responsible for this problem. A recent map shows the Dead Zone covering more than 6,000 square miles—an area roughly the size of New Jersey.This area of low oxygen stretches from the Mississippi River to Texas. The size of the dead zone has more than doubled in size since the early 1990s. What is Being Done? Considerable attention and support has been given to improve water quality and lessen these downstream impacts. Many state and local organizations are working on clean up efforts across the basin. You can learn more about water quality issues or find out more about particular watersheds within the basin or how you can get involved. While the virtual tour gives a flavor of the Minnesota River Basin, the real exploration awaits. Come visit. Plan a trip to some of the intriguing natural and cultural sites along this National Scenic Byway. The tour ends here. Hope you enjoyed the trip (Credits).

\| map \| 1 \| 2 \| 3 \| 4 \| 5 \| 6 \| 7 \| 8 \| 9 \| 10 \| 11 \| 12 \| basin overview \| home \|
I would like to learn more about: \| minnesota river basin \| watersheds \| water quality \| contacts \| home \|