News about the RRWMB and its associated stakeholders and projects
The North Ottawa Impoundment Project, developed by the Bois de Sioux Watershed District, is officially complete. The impoundment controls 75 square miles of the 320 square mile Rabbit River Watershed in Grant and Otter Tail Counties by storing the excess runoff on 1,920 acres of land.
Dikes constructed around the perimeter of the impoundment form a holding area, and partitions within the interior provide a complex of sub-impoundments. Waters carried by existing drainage ditches are intercepted by diversion channels, and brought into the impoundment through a diked inlet channel.
The impoundment has 100% of its storage capacity available for the spring runoff. After spring runoff, the water is released as quickly as possible to restore about 80% the impoundment’s capacity. The remaining 20% is drawn out slowly over the balance of the year while providing the secondary benefits.
In addition to flood control, the impoundment is being used for multiple purposes including natural resource enhancement and water quality improvement.
“We’re very pleased by the flood protection and other benefits provided by North Ottawa,” said Jerome Deal of the Bois de Sioux River Watershed District Board of Managers. “We think this work will provide valuable information on how impoundments in other parts of Minnesota can be built and operated to maximize their use for multiple purposes.”