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The Mississippi River is one of the world’s greatest river systems. From its headwaters in Lake Itasca to the Gulf of Mexico, it drains all or part of 31 states and spans 2,350 sq miles.This unique body of water has played an integral role in shaping the nation’s historical, cultural and economic heritage.
Near the headwaters of the Mississippi, the river flows through Little Falls, a community of about 8,000 people. It provides picturesque scenery, a popular recreation spot and much of the town’s history and development.
Because the Mississippi River plays such a large part in the lives of the people of Little Falls, preserving its quality is of great importance to the city’s residents.
When a city street that runs along the riverbank in Little Falls needed improvements, treatment of the storm water runoff was a top priority. The site also presented dewatering issues, and aesthetics were important. Storm water runoff pollutants of concern included oil, grease, nutrients and sediment.
An underground treatment system was the obvious choice.The civil engineer on the project, Don Anderson of Widseth Smith Nolting, chose to install a Vortechs system.
Due to the difficult site conditions, the Vortechs system offered the best solution when compared to competitors. Its unique shallow profile allowed for greater ease of installation and less dewatering over the proposed deep sump competitor.
The contractor on the project, Kuechle Underground of Kimball, Minn., appreciated the easy installation. The system arrived on site with all components preassembled by the precaster, allowing the contractor to install the unit—including the bypass structures—in less than three hours.
The Vortechs Model 5000 treats storm water runoff flows of up to 8.5 cu ft per second, removing suspended solids and other pollutants that otherwise would have been discharged directly into the Mississippi River.
The city of Little Falls was impressed with how straightforward the system is to inspect and maintain. Access to the grit chamber is unobstructed, and removal of captured pollutants with a vactor truck hose poses no difficulty. Regular maintenance is scheduled in order to ensure that the system will function at its maximum capacity.