New Cooperative reveals county drainage tile under retention basin; engineers propose reroute options

A New Cooperative representative told Dickinson County supervisors that contractor surveyors found an existing county drainage tile in the footprint of a retention basin for a new fertilizer building in Superior, and presented engineering options to avoid damaging county drainage infrastructure.

“My contractor located the tile… it is a 12 inch or 11 and 3 quarter inch outside diameter tile, clay tile,” Frank Huseman said as he reviewed geo-referenced survey points for the site. He said Beck Engineering located the tile while preparing the site and that the tile sits at the bottom of a planned retention pond.

Huseman outlined three options developed with engineers: 1) reroute the tile laterally across the basin with trenching and rodent-control measures to reconnect the line, 2) raise the basin bottom above the tile (declared nonviable because it would reduce basin capacity by several feet), or 3) relocate the tile along the south side and run it back east to reconnect downstream while preserving basin capacity.

Supervisors and engineers urged site teams to examine historic drainage-district maps, check plat records and use tracer runs to confirm whether additional lateral connections exist to the north before committing to any reroute. County staff said reclassification of drainage-district records and retention of maps documenting any change would be needed so future users could trace the tile’s new route. Huseman said New Cooperative expects to pay project costs associated with relocation and will coordinate with Beck Engineering and the drainage office to return with updated plans.

No formal county action was taken at the meeting; supervisors asked staff to follow up and requested formal documentation of any reroute for the drainage district’s records.