Faribault County Ditch No. 62
Faribault County, MN | agriculture
ISG designed bioreactors for a watershed area that enable environmentally friendly drainage that meets the area’s capacity needs.
This 700-acre watershed that drains into the Blue Earth River had a tile outlet that was in poor condition, damaged, and failing in many areas.
To find a solution for a damaged tile outlet, a partnership was developed among the Drainage Authority, Faribault County Soil and Water Conservation District (SWCD), and a landowner who offered a grassed swale site that was ideal for bioreactors. ISG designed three bioreactors into the drainage repair to maximize the efficiency of nitrate reduction while also meeting the time limitations for water storage. Each bioreactor is 135x25x5 feet deep and is aligned with tile so each can be filled consecutively once capacity is met. This increases effectiveness as more peakflow from the system is treated. A stormwater quality unit was also installed to remove sediment and debris prior to entering the bioreactors. This water quality project did not take land out of production and utilized grant funding.