North Ottawa Impoundment Project
The impoundment will control 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. The project involves constructing dikes around the perimeter of the impoundment area, building a collection system to bring water into the impoundment, and partitioning the interior to provide a complex of subimpoundments. Waters carried by existing drainage ditches will be intercepted by diversion channels, and brought into the impoundment through a diked inlet channel.
Flood Damage Reduction (Primary objective): Provides 16,000 acre feet of gate-controlled storage which is equivalent to 75% of the estimated 100 year spring runoff. This is expected to reduce peak flows on the Bois de Sioux River at Wahpeton/Breckenridge by about 5%.
Downstream Flow Augmentation:
Release of about 5 cfs flow during the ice free season in most years.
Improvement via sedimentation and nutrient uptake by plants.
Flooding: Local-10 to 15 square miles of ag land flooded frequently; Regional - Wahpeton/Breckenridge urban flooding; Farmstead, machinery and grain storage damage Erosion and Sedimentation: Streambank and sheet erosion, Streambed sedimentation.
- Red River Watershed Management Board
- State of Minnesota
- Bois de Sioux Watershed District