Open the Gates

Open the Gates. . , The gates of the Coon Rapids Dam have changed throughout the years to keep up with flow of the Mississippi River. The Coon Rapids Dam was built in 1913 to generate electric power for a proposed trolley line. The metal structure you see before you is called a Tainter gate. From 1913 to 1995, the Coon Rapids Dam utilized twenty-eight such gates to control the flow of the Mississippi River. Each curved gate pivoted on a large pin. It took 100 turns of the crank by hand the raise the gate only one inch., When the Tainter gates could no longer operate effectively, inflatable rubber dam sections were installed. The new inflatable rubber gates were completed in 1997, making the Coon Rapids Dam one of the largest rubber dams in North America. Due to the harsh Minnesota winters, there were challenges with the rubber dams functioning properly., Finally, hydraulic steel crest gates replaced the rubber gates in 2015. These gates range between 67 and 97 feet long, 8 feet high, and weigh between 32 to 45 tons. In addition to being a more effective gate for water level control, these steel crest gates help with preventing the migration of Asian carp (an invasive fish species) threatening the Mississippi's headwaters ecosystem., To learn more about the history of the Coon Rapids Dam, stop by the visitors center, , Mississippi Watershed , A watershed is the area drained by a river and its tributaries. , Largest drainage basin in North America , 1,245,000 square miles, The Mississippi watershed covers 40% of the landmass of the continental United States, Reaches 32 U.S. states and 2 Canadian provinces, , Facts of the Mississippi. , The Mississippi River is 2,350 miles long, It would take 90 days for a drop of water to travel the entire length of the Mississippi River, The Mississippi discharges 593,003 cubic feet of water per second into the Gulf of Mexico That is enough water to fill 55,512 bathtubs, In comparison, the Amazon discharges 7,380,765 cubic feet per second, , Wildlife of the Mississippi. , 260 fish species or 25% of all fish species in North America live in the Mississippi, 60% of all North American birds (326 species) use the Mississippi as a migratory flyway, 50 mammal species live in the Upper Mississippi (from the headwaters to Illinois), 145 species of amphibians and reptiles inhabit the Upper Mississippi River environs